Integrated Taxonomic Information System - Taxon Author Search Results

Source: Asteraceae of North America Update, database (version 2010.5.13)

ITIS records citing this source
 
 Kingdom Plantae
  Acamptopappus (A. Gray) A. Gray -- accepted -- goldenhead
  Acamptopappus shockleyi A. Gray -- accepted -- Shockley's goldenhead
  Acamptopappus sphaerocephalus (Harv. & A. Gray ex A. Gray) A. Gray -- accepted -- rayless goldenhead
  Acamptopappus sphaerocephalus var. hirtellus S.F. Blake -- accepted -- rayless goldenhead
  Acamptopappus sphaerocephalus var. sphaerocephalus (Harv. & A. Gray ex A. Gray) A. Gray -- accepted -- rayless goldenhead
  Acanthospermum Schrank -- accepted -- starbur, starburr
  Acanthospermum australe (Loefl.) Kuntze -- accepted -- Paraguayan starbur, southern starbur, Paraguayan starburr
  Acanthospermum hispidum DC. -- accepted -- hispid starbur, hispid starburr, bristly starbur
  Acanthospermum humile (Sw.) DC. -- accepted -- low starbur, low starburr
  Acanthospermum xanthioides DC. -- not accepted -- southern starburr
  Acanthoxanthium spinosum (L.) Fourr. -- not accepted
  Achaetogeron chihuahuensis Larsen -- not accepted
  Achaetogeron versicolor Greenm. -- not accepted
  Achillea L. -- accepted -- yarrow
  Achillea aegyptiaca L. -- accepted
  Achillea ageratifolia (Sm.) Boiss. -- accepted -- yarrow
  Achillea ageratum L. -- accepted -- sweet-Nancy, sweet yarrow
  Achillea alpicola (Rydb.) Rydb. -- not accepted
  Achillea alpina L. -- accepted -- Chinese yarrow, Siberian yarrow
  Achillea angustissima Rydb. -- not accepted
  Achillea arenicola A. Heller -- not accepted
  Achillea aspleniifolia auct. non Vent. -- not accepted
  Achillea biserrata M. Bieb. -- accepted
  Achillea borealis Bong. -- not accepted
  Achillea borealis ssp. arenicola (A. Heller) D.D. Keck -- not accepted
  Achillea borealis ssp. californica (Pollard) D.D. Keck -- not accepted
  Achillea borealis ssp. typica D.D. Keck -- not accepted
  Achillea borealis var. arenicola (A. Heller) J.T. Howell -- not accepted
  Achillea borealis var. californica (Pollard) J.T. Howell -- not accepted
  Achillea californica Pollard -- not accepted
  Achillea cartilaginea Ledeb. ex Rchb. -- accepted
  Achillea chrysocoma Friv. -- accepted
  Achillea clavennae L. -- accepted
  Achillea clusiana Tausch -- accepted
  Achillea clypeolata Sm. -- accepted
  Achillea collina Becker ex Rchb. -- accepted
  Achillea conferta DC. -- accepted
  Achillea crithmifolia Waldst. & Kit. -- accepted
  Achillea dentifera DC. -- not accepted
  Achillea distans Waldst. & Kit. ex Willd. -- accepted -- Alps yarrow
  Achillea distans ssp. tanacetifolia (All.) Janch. -- accepted
  Achillea eradiata Piper -- not accepted
  Achillea erba-rotta All. -- accepted
  Achillea erba-rotta ssp. rupestris (Porta) I. Richardson -- accepted
  Achillea filipendulina Lam. -- accepted -- fernleaf yarrow
  Achillea fusca Rydb. -- not accepted
  Achillea gigantea Pollard -- not accepted
  Achillea gracilis Raf. -- not accepted
  Achillea grandifolia Friv. -- accepted
  Achillea impatiens L. -- accepted
  Achillea lanulosa Nutt. -- not accepted -- western yarrow
  Achillea lanulosa ssp. alpicola (Rydb.) D.D. Keck -- not accepted
  Achillea lanulosa ssp. megacephala (Raup) Argus -- not accepted
  Achillea lanulosa ssp. typica D.D. Keck -- not accepted
  Achillea lanulosa var. alpicola Rydb. -- not accepted
  Achillea lanulosa var. arachnoidea Lunell -- not accepted
  Achillea lanulosa var. eradiata (Piper) M. Peck -- not accepted
  Achillea laxiflora Pollard & Cockerell -- not accepted
  Achillea ligustica All. -- accepted -- Ligurian yarrow
  Achillea lingulata Waldst. & Kit. -- accepted
  Achillea macrocephala Rupr. -- accepted
  Achillea macrophylla L. -- accepted
  Achillea magna auct. -- not accepted
  Achillea megacephala Raup -- not accepted
  Achillea millefolium L. -- accepted -- common yarrow, milenrama, milfoil, western yarrow, bloodwort, carpenter's weed, hierba de las cortaduras, plumajillo, yarrow
  Achillea millefolium ssp. atrotegula B. Boivin -- not accepted
  Achillea millefolium ssp. borealis (Bong.) Breitung -- not accepted
  Achillea millefolium ssp. lanulosa (Nutt.) Piper -- not accepted
  Achillea millefolium ssp. occidentalis (DC.) Hyl. -- not accepted
  Achillea millefolium ssp. pallidotegula B. Boivin -- not accepted
  Achillea millefolium var. alpicola (Rydb.) Garrett -- not accepted -- common yarrow
  Achillea millefolium var. arenicola (A. Heller) Nobs -- not accepted -- common yarrow
  Achillea millefolium var. aspleniifolia (Vent.) Farw. -- not accepted
  Achillea millefolium var. borealis (Bong.) Farw. -- not accepted -- boreal yarrow
  Achillea millefolium var. californica (Pollard) Jeps. -- not accepted -- California yarrow
  Achillea millefolium var. fulva B. Boivin -- not accepted
  Achillea millefolium var. fusca (Rydb.) G.N. Jones -- not accepted
  Achillea millefolium var. gigantea (Pollard) Nobs -- not accepted -- giant yarrow
  Achillea millefolium var. gracilis (Raf.) Raf. ex DC. -- not accepted
  Achillea millefolium var. lanulosa (Nutt.) Piper -- not accepted
  Achillea millefolium var. litoralis Ehrend. ex Nobs -- not accepted -- coast yarrow
  Achillea millefolium var. maritima Jeps. -- not accepted
  Achillea millefolium var. megacephala (Raup) B. Boivin -- not accepted -- largehead yarrow
  Achillea millefolium var. millefolium L. -- not accepted -- common yarrow
  Achillea millefolium var. nigrescens E. Mey. -- not accepted -- common yarrow
  Achillea millefolium var. occidentalis DC. -- not accepted -- western yarrow, common yarrow
  Achillea millefolium var. pacifica (Rydb.) G.N. Jones -- not accepted -- Pacific yarrow
  Achillea millefolium var. parviligula B. Boivin -- not accepted
  Achillea millefolium var. parvula B. Boivin -- not accepted
  Achillea millefolium var. puberula (Rydb.) Nobs -- not accepted -- common yarrow
  Achillea millefolium var. rosea (Desf.) Torr. & A. Gray -- not accepted
  Achillea millefolium var. russeolata B. Boivin -- not accepted
  Achillea multiflora Hook. -- not accepted
  Achillea nigrescens (E. Mey.) Rydb. -- not accepted
  Achillea nobilis L. -- accepted -- noble yarrow
  Achillea occidentalis (DC.) Raf. ex Rydb. -- not accepted
  Achillea odorata L. -- accepted
  Achillea pacifica Rydb. -- not accepted
  Achillea pannonica Scheele -- accepted
  Achillea ptarmica L. -- accepted -- sneezeweed
  Achillea ptarmica ssp. macrocephala (Rupr.) Heimerl -- not accepted
  Achillea puberula Rydb. -- not accepted
  Achillea pyrenaica Sibth. ex Godr. -- accepted
  Achillea rosea Desf. -- not accepted
  Achillea rupestris Porta -- not accepted
  Achillea setacea Waldst. & Kit. -- accepted
  Achillea sibirica Ledeb. -- not accepted -- Siberian yarrow, achillée de Sibérie
  Achillea subalpina Greene -- not accepted
  Achillea tanacetifolia All. -- not accepted
  Achillea taygetea Boiss. & Heldr. -- not accepted
  Achillea tomentosa Pursh non L. -- not accepted
  Achillea umbellata Sm. -- accepted
  Achyrachaena Schauer -- accepted -- blow wives
  Achyrachaena mollis Schauer -- accepted -- blow wives, soft blow wives
  Achyrophorus roseus Less. -- not accepted
  Acmella Rich. ex Pers. -- accepted -- spotflower
  Acmella decumbens (Sm.) R.K. Jansen -- accepted -- creeping spotflower
  Acmella iodiscaea (A.H. Moore) R.K. Jansen -- accepted -- maluco
  Acmella oppositifolia (Lam.) R.K. Jansen -- accepted -- oppositeleaf spotflower
  Acmella oppositifolia var. repens (Walter) R.K. Jansen -- not accepted -- oppositeleaf spotflower, creeping spotflower
  Acmella pilosa R.K. Jansen -- accepted -- hairy spotflower
  Acmella pusilla (Hook. & Arn.) R.K. Jansen -- accepted -- dwarf spotflower
  Acmella repens (Walter) Rich. -- accepted -- oppositeleaf spotflower
  Acmella uliginosa (Sw.) Cass. -- accepted
  Acosta diffusa (Lam.) Soják -- not accepted
  Acosta maculosa auct. non (Lam.) Holub -- not accepted
  Acourtia D. Don -- accepted -- desertpeony, desert peony
  Acourtia microcephala DC. -- accepted -- sacapellote
  Acourtia nana (A. Gray) Reveal & King -- accepted -- dwarf desertpeony, desert holly
  Acourtia runcinata (Lag. ex D. Don) B.L. Turner -- accepted -- featherleaf desertpeony
  Acourtia thurberi (A. Gray) Reveal & King -- accepted -- Thurber's desertpeony
  Acourtia wrightii (A. Gray) Reveal & King -- accepted -- brownfoot, pink perezzia, Wright's desertpeony
  Acroclinium roseum Hook. -- not accepted
  Acroptilon Cass. -- accepted -- hardheads, acroptilon, Russian knapweed
  Acroptilon repens (L) DC -- not accepted -- hardheads, Russian knapweed, Turestan thistle
  Actinea acaulis (Pursh) Spreng. -- not accepted
  Actinea acaulis var. arizonica (Greene) S.F. Blake -- not accepted
  Actinea canescens (D.C. Eaton) S.F. Blake -- not accepted
  Actinea cooperi (A. Gray) Kuntze -- not accepted
  Actinea grandiflora (Torr. & A. Gray ex A. Gray) Kuntze -- not accepted
  Actinea herbacea (Greene) B.L. Rob. -- not accepted
  Actinea richardsonii (Hook.) Kuntze -- not accepted
  Actinea vaseyi (A. Gray) Kuntze -- not accepted
  Actinella acaulis (Pursh) Nutt. -- not accepted
  Actinella argentea A. Gray -- not accepted
  Actinella richardsonii var. floribunda A. Gray -- not accepted
  Actinomeris alternifolia (L) DC -- not accepted
  Actinomeris helianthoides (Michx.) Nutt. -- not accepted
  Actinomeris helianthoides var. elliottii DC. -- not accepted
  Actinomeris helianthoides var. nuttallii DC. -- not accepted
  Actinomeris heterophylla Chapm. -- not accepted
  Actinomeris longifolia A. Gray -- not accepted
  Actinomeris nudicaulis Nutt. -- not accepted
  Actinomeris oppositifolia DC. -- not accepted
  Actinomeris pauciflora Nutt. -- not accepted
  Actinospermum Elliott -- not accepted
  Actinospermum angustifolium (Pursh) Torr. & A. Gray -- not accepted
  Adenocaulon Hook. -- accepted -- trailplant
  Adenocaulon bicolor Hook. -- accepted -- American trailplant
  Adenophyllum Pers. -- accepted -- dogweed
  Adenophyllum cooperi (A. Gray) Strother -- accepted -- Cooper's dogweed, Cooper's dyssodia
  Adenophyllum porophylloides (A. Gray) Strother -- accepted -- San Felipe dogweed, San Felipe dyssodia
  Adenophyllum porophyllum (Cav.) Hemsl. -- accepted -- poreleaf dogweed
  Adenophyllum wrightii A. Gray -- accepted -- Wright's dogweed
  Adenostemma J.R. Forst. & G. Forst. -- accepted -- medicineplant
  Adenostemma berteroi DC. -- accepted
  Adenostemma lanceolatum Miq. -- accepted
  Adenostemma lavenia (L.) Kuntze -- not accepted -- common medicineplant
  Adenostemma verbesina (L.) Sch. Bip. -- accepted -- tropical medicineplant
  Adenostemma viscosum J.R. Forst. & G. Forst. -- accepted -- common medicineplant
  Agarista calliopsidea DC. -- not accepted
  Agassizia suavis A. Gray & Engelm. -- not accepted
  Ageratina Spach -- accepted -- snakeroot
  Ageratina adenophora (Spreng.) King & H. Rob. -- accepted -- sticky snakeroot, crofton weed, Maui pamakani, Mexican devil
  Ageratina altissima (L.) King & H. Rob. -- accepted -- white snakeroot
  Ageratina altissima var. altissima (L.) King & H. Rob. -- accepted -- white snakeroot
  Ageratina altissima var. angustata (A. Gray) Clewell & Woot. -- not accepted -- white snakeroot
  Ageratina altissima var. roanensis (Small) Clewell & Woot. -- accepted -- white snakeroot
  Ageratina aromatica (L.) Spach -- accepted -- lesser snakeroot
  Ageratina aromatica var. aromatica (L.) Spach -- not accepted -- lesser snakeroot
  Ageratina aromatica var. incisa (A. Gray) C.F. Reed -- not accepted -- lesser snakeroot
  Ageratina havanensis (Kunth) King & H. Rob. -- accepted -- Havana snakeroot, shrubby boneset
  Ageratina herbacea (A. Gray) King & H. Rob. -- accepted -- fragrant snakeroot, herbaceous joepyeweed
  Ageratina jucunda (Greene) Clewell & Woot. -- accepted -- hammock snakeroot, lesser snakeroot
  Ageratina lemmonii (B.L. Rob.) King & H. Rob. -- accepted -- Lemmon's snakeroot
  Ageratina luciae-brauniae (Fernald) King & H. Rob. -- accepted -- Lucy Braun's snakeroot
  Ageratina occidentalis (Hook.) King & H. Rob. -- accepted -- western snakeroot, western eupatorium, western joepyeweed
  Ageratina paupercula (A. Gray) King & H. Rob. -- accepted -- Santa Rita snakeroot
  Ageratina resiniflua (Urb.) King & H. Rob. -- accepted -- resinous snakeroot
  Ageratina riparia (Regel) King & H. Rob. -- accepted -- spreading snakeroot, creeping croftonweed, mist flower
  Ageratina rothrockii (A. Gray) King & H. Rob. -- accepted -- Rothrock's snakeroot
  Ageratina shastensis (D.W. Taylor & Stebbins) King & H. Rob. -- accepted -- Shasta snakeroot
  Ageratina thyrsiflora (Greene) R.M. King & H. Rob. -- accepted -- congested snakeroot
  Ageratina wrightii (A. Gray) King & H. Rob. -- accepted -- Wright's snakeroot
  Ageratum L. -- accepted -- whiteweed, ageratum
  Ageratum altissimum L. non Eupatorium altissimum L. -- not accepted
  Ageratum conyzoides L. -- accepted -- tropical whiteweed
  Ageratum corymbosum Zuccagni ex Pers. -- accepted -- flat-top whiteweed, flattop whiteweed
  Ageratum domingense Spreng. -- accepted
  Ageratum guatemalense M.F. Johnson -- not accepted
  Ageratum houstonianum Mill. -- accepted -- bluemink
  Ageratum littorale A. Gray -- not accepted -- Cape Sable whiteweed
  Ageratum maritimum Kunth -- accepted -- Cape Sable whiteweed
  Agnorhiza (Jeps.) W.A. Weber -- accepted
  Agnorhiza bolanderi (A. Gray) W.A. Weber -- accepted -- Bolander's mule-ears
  Agnorhiza elata (H.M. Hall) W.A. Weber -- accepted -- Hall's mule-ears
  Agnorhiza invenusta (Greene) W.A. Weber -- accepted -- Coville's mule-ears
  Agnorhiza ovata (Torr. & A. Gray ex Torr.) W.A. Weber -- accepted -- southern mule-ears
  Agnorhiza reticulata (Greene) W.A. Weber -- accepted -- El Dorado mule-ears
  Agoseris Raf. -- accepted -- agoseris, mountain dandelion
  Agoseris agrestis Osterh. -- not accepted
  Agoseris alpestris (A. Gray) Greene -- not accepted
  Agoseris apargioides (Less.) Greene -- accepted -- woolly goat chicory
  Agoseris apargioides ssp. maritima (Sheldon) Q. Jones -- not accepted
  Agoseris apargioides var. apargioides (Less.) Greene -- accepted -- woolly goat chicory
  Agoseris apargioides var. eastwoodiae (Fedde) Munz -- accepted -- woolly goat chicory
  Agoseris apargioides var. maritima (Sheldon) Q. Jones ex Cronquist -- accepted -- woolly goat chicory
  Agoseris arizonica Greene -- not accepted
  Agoseris aurantiaca (Hook.) Greene -- accepted -- orange agoseris, orange-flowered false-dandelion
  Agoseris aurantiaca ssp. purpurea (A. Gray) G.W. Douglas -- not accepted
  Agoseris aurantiaca var. aurantiaca (Hook.) Greene -- accepted -- orange agoseris, Mill Creek agoseris
  Agoseris aurantiaca var. purpurea (A. Gray) Cronquist -- accepted -- orange agoseris, pale agoseris
  Agoseris barbellulata (Greene ex A. Gray) Greene -- not accepted
  Agoseris cuspidata (Pursh) Raf. -- not accepted
  Agoseris eastwoodiae Fedde -- not accepted
  Agoseris elata (Nutt.) Greene -- not accepted -- tall agoseris
  Agoseris glauca (Pursh) Raf. -- accepted -- pale agoseris, prairie dandelion, pale dandelion
  Agoseris glauca ssp. scorzonerifolia (Schrad.) Piper -- not accepted
  Agoseris glauca var. agrestis (Osterh.) Q. Jones ex Cronquist -- not accepted -- pale agoseris
  Agoseris glauca var. asper (Rydb.) Cronquist -- not accepted
  Agoseris glauca var. cronquistii S.L. Welsh -- not accepted -- pale agoseris
  Agoseris glauca var. dasycephala (Torr. & A. Gray) Jeps. -- accepted -- pale goat-chicory, pale agoseris
  Agoseris glauca var. glauca (Pursh) Raf. -- accepted -- pale agoseris
  Agoseris glauca var. laciniata (D.C. Eaton) Smiley -- not accepted -- false agoseris, Arizona mountain dandelion
  Agoseris glauca var. monticola (Greene) Q. Jones ex Cronquist -- not accepted -- pale agoseris
  Agoseris glauca var. parviflora (Nutt.) Rydb. -- not accepted
  Agoseris glauca var. pumila (Nutt.) Garrett -- not accepted
  Agoseris graminifolia Greene -- not accepted
  Agoseris grandiflora (Nutt.) Greene -- accepted -- bigflower agoseris, shortbeak agoseris
  Agoseris grandiflora var. grandiflora (Nutt.) Greene -- accepted
  Agoseris grandiflora var. leptophylla G.I. Baird -- accepted
  Agoseris heterophylla (Nutt.) Greene -- accepted -- annual agoseris, annual goatsbeard, mountain dandelion
  Agoseris heterophylla ssp. californica (Nutt.) Piper -- not accepted
  Agoseris heterophylla ssp. normalis Piper -- not accepted
  Agoseris heterophylla var. crenulata Jeps. -- not accepted -- annual agoseris
  Agoseris heterophylla var. cryptopleura Jeps. -- accepted -- California agoseris, annual agoseris
  Agoseris heterophylla var. heterophylla (Nutt.) Greene -- accepted -- annual agoseris
  Agoseris heterophylla var. kymapleura Greene -- not accepted
  Agoseris heterophylla var. quentinii G.I. Baird -- accepted -- Arizona agoseris
  Agoseris heterophylla var. turgida (H.M. Hall) Jeps. -- not accepted -- annual agoseris
  Agoseris hirsuta (Hook.) Greene -- not accepted
  Agoseris laciniata (Nutt.) Greene -- not accepted
  Agoseris lackschewitzii Douglass M. Hend. & R. Moseley -- not accepted -- Mill Creek agoseris
  Agoseris maritima Sheldon -- not accepted
  Agoseris monticola Greene -- accepted -- pale agoseris
  Agoseris parviflora (Nutt.) Greene -- accepted -- Steppe agoseris, false agoseris
  Agoseris plebeja (Greene) Greene -- not accepted
  Agoseris retrorsa (Benth.) Greene -- accepted -- spearleaf agoseris
  Agoseris rostrata Rydb. -- not accepted
  Agoseris scorzonerifolia (Schrad.) Greene -- not accepted
  Agoseris turbinata Rydb. -- not accepted
  Agoseris X agrestis Osterh. (pro sp.) -- accepted -- pale agoseris
  Agoseris X dasycarpa Greene -- accepted
  Agoseris X elata (Nutt.) Greene (pro sp.) -- accepted -- tall agoseris
  Alcina perfoliata Cav. -- not accepted
  Almutaster Á. Löve & D. Löve -- accepted -- alkali marsh aster, almutaster
  Almutaster pauciflorus (Nutt.) A. Löve & D. Löve -- accepted -- alkali marsh aster, alkali-marsh aster
  Amauria dissecta A. Gray -- not accepted
  Amauriopsis Rydb. -- accepted
  Amauriopsis dissecta (A. Gray) Rydb. -- accepted -- ragleaf bahia
  Amberboa (Pers.) Less. -- accepted -- amberboa
  Amberboa moschata (L) DC -- accepted -- sweetsultan
  Amblyolepis DC. -- accepted -- amblyolepis
  Amblyolepis setigera DC. -- accepted -- huisachedaisy, huisache daisy
  Amblyopappus Hook. & Arn. -- accepted -- amblyopappus
  Amblyopappus pusillus Hook. & Arn. -- accepted -- dwarf coastweed
  Ambrosia L. -- accepted -- ragweed, bursage
  Ambrosia acanthicarpa Hook. -- accepted -- flatspine bur ragweed, flatspine burr ragweed, bursage, bursage ragweed, flat-spine burr-ragweed, annual bursage, sand bursage
  Ambrosia ambrosioides (Cav.) Payne -- accepted -- ambrosia leaf bur ragweed, ambrosia leaf burr ragweed, big bursage, ambrosia bursage
  Ambrosia aptera DC. -- not accepted
  Ambrosia artemisiifolia L. -- accepted -- annual ragweed, common ragweed, ragweed, low ragweed, Roman wormwood, short ragweed, small ragweed
  Ambrosia artemisiifolia var. artemisiifolia L. -- not accepted -- annual ragweed, ragweed, common ragweed
  Ambrosia artemisiifolia var. elatior (L.) Descourtils -- not accepted -- annual ragweed, common ragweed, ragweed
  Ambrosia artemisiifolia var. paniculata (Michx.) Blank. -- not accepted -- annual ragweed, common ragweed, ragweed
  Ambrosia bidentata Michx. -- accepted -- lanceleaf ragweed
  Ambrosia californica Rydb. -- not accepted
  Ambrosia canescens A. Gray -- accepted -- hairy ragweed
  Ambrosia chamissonis (Less.) Greene -- accepted -- silver bur ragweed, silver burr ragweed, beach-bur
  Ambrosia chamissonis var. bipinnatisecta (Less.) J.T. Howell -- not accepted
  Ambrosia cheiranthifolia A. Gray -- accepted -- Rio Grande ragweed, South Texas ambrosia
  Ambrosia chenopodiifolia (Benth.) Payne -- accepted -- San Diego bur ragweed, San Diego burr ragweed, San Diego bursage
  Ambrosia confertiflora DC. -- accepted -- weakleaf bur ragweed, weakleaf burr ragweed, ragweed
  Ambrosia cordifolia (A. Gray) Payne -- accepted -- Tucson bur ragweed, Tucson burr ragweed, heartleaf bursage
  Ambrosia coronopifolia Torr. & A. Gray -- not accepted
  Ambrosia cumanensis auct. non Kunth -- not accepted
  Ambrosia deltoidea (Torr.) Payne -- accepted -- triangle bur ragweed, triangle burr ragweed, triangle bursage
  Ambrosia dumosa (A. Gray) Payne -- accepted -- burrobush, white bursage
  Ambrosia elatior L. -- not accepted
  Ambrosia eriocentra (A. Gray) Payne -- accepted -- woolly fruit bur ragweed, woolly fruit burr ragweed, woolly bursage, hollyleaf bursage, wooly bursage
  Ambrosia glandulosa Scheele -- not accepted
  Ambrosia grayi (A. Nelson) Shinners -- accepted -- woollyleaf bur ragweed, woollyleaf burr ragweed, bur ragweed, lagoonweed, woollyleaf bursage, woollyleaf franseria, woollyleaf povertyweed
  Ambrosia hispida Pursh -- accepted -- coastal ragweed
  Ambrosia ilicifolia (A. Gray) Payne -- accepted -- hollyleaf bur ragweed, hollyleaf burr ragweed, hollyleaf bursage
  Ambrosia linearis (Rydb.) Payne -- accepted -- streaked bur ragweed, streaked burr ragweed
  Ambrosia monogyra (Torr. & A. Gray) Strother & B.G. Baldw. -- accepted -- singlewhorl burrobrush
  Ambrosia monophylla (Walter) Rydb. -- not accepted
  Ambrosia paniculata Michx. -- not accepted
  Ambrosia peruviana Willd. -- accepted -- Peruvian ragweed
  Ambrosia psilostachya DC. -- accepted -- Cuman ragweed, western ragweed, perennial ragweed
  Ambrosia psilostachya var. californica (Rydb.) S.F. Blake -- not accepted
  Ambrosia psilostachya var. coronopifolia (Torr. & A. Gray) Farw. -- not accepted
  Ambrosia psilostachya var. lindheimeriana (Scheele) Blank. -- not accepted
  Ambrosia pumila (Nutt.) A. Gray -- accepted -- dwarf bur ragweed, San Diego ambrosia, dwarf burr ragweed, San Diego ragweed
  Ambrosia rugelii Rydb. -- not accepted
  Ambrosia salsola (Torr. & A. Gray) Strother & B.G. Baldw. -- accepted -- burrobrush
  Ambrosia salsola var. fasciculata (A. Nelson) Strother & B.G. Baldw. -- not accepted
  Ambrosia salsola var. pentalepis (Rydb.) Strother & B.G. Baldw. -- not accepted
  Ambrosia salsola var. salsola (Torr. & A. Gray) Strother & B.G. Baldw. -- not accepted
  Ambrosia sandersonii S.L. Welsh -- not accepted
  Ambrosia tenuifolia Spreng. -- accepted -- slimleaf bur ragweed, slimleaf burr ragweed, field ragweed
  Ambrosia tomentosa Nutt. -- accepted -- skeletonleaf bur ragweed, skeletonleaf burr ragweed, skeleton-leaf burr-ragweed, skeletonleaf bursage
  Ambrosia trifida L. -- accepted -- great ragweed, Texan great ragweed, giant ragweed, tall ragweed, blood ragweed, perennial ragweed, horseweed
  Ambrosia trifida var. aptera (DC.) Kuntze -- not accepted
  Ambrosia trifida var. integrifolia (Muhl. ex Willd.) Torr. & A. Gray -- not accepted
  Ambrosia trifida var. texana Scheele -- not accepted -- Texan great ragweed, giant ragweed, great ragweed
  Ambrosia trifida var. trifida L. -- not accepted -- great ragweed, giant ragweed
  Ambrosia X helenae Rouleau -- accepted -- Helen ragweed
  Ambrosia X intergradiens W.H. Wagner -- accepted -- intergrading ragweed
  Ambrosia X platysperma (Seaman) Strother & B.G. Baldw. -- accepted
  Amellus spinulosus Pursh non Machaeranthera spinulosus Greene -- not accepted
  Ammodia oregona Nutt. -- not accepted
  Ammopursus ohlingerae (S.F. Blake) Small -- not accepted
  Ampelaster G.L. Nesom -- accepted -- climbing aster
  Ampelaster carolinianus (Walter) G.L. Nesom -- accepted -- climbing aster
  Amphiachyris (A. DC.) Nutt. -- accepted -- broomweed, amphiachyris
  Amphiachyris amoena (Shinners) Solbrig -- accepted -- Texas broomweed
  Amphiachyris dracunculoides (DC.) Nutt. -- accepted -- prairie broomweed, common broomweed
  Amphiachyris spinosa A. Nelson -- not accepted
  Amphipappus Torr. & A. Gray -- accepted -- chaffbush, amphipappus
  Amphipappus fremontii Torr. & A. Gray ex A. Gray -- accepted -- Fremont's chaffbush, chaffbush
  Amphipappus fremontii ssp. fremontii Torr. & A. Gray ex A. Gray -- not accepted -- Fremont's chaffbush
  Amphipappus fremontii ssp. spinosus (A. Nelson) D.D. Keck -- not accepted -- Fremont's chaffbush, chaffbush
  Amphipappus fremontii var. fremontii Torr. & A. Gray ex A. Gray -- accepted -- chaff-bush, Fremont's chaffbush
  Amphipappus fremontii var. spinosus (A. Nelson) Ced. Porter -- accepted -- Fremont's chaffbush
  Anacyclus L. -- accepted -- anacyclus
  Anacyclus clavatus (Desf.) Pers. -- accepted -- whitebuttons
  Anacyclus tomentosus DC. -- not accepted
  Anaphalis DC. -- accepted -- pearly everlasting, anaphalis, pearlyeverlasting
  Anaphalis margaritacea (L.) Benth. -- accepted -- western pearly everlasting, common pearlyeverlasting, pearly-everlasting, pearly everlasting, western pearlyeverlasting
  Anaphalis margaritacea var. angustior (Miq.) Nakai -- not accepted
  Anaphalis margaritacea var. intercedens H. Hara -- not accepted
  Anaphalis margaritacea var. occidentalis Greene -- not accepted
  Anaphalis margaritacea var. revoluta Suksd. -- not accepted
  Anaphalis margaritacea var. subalpina A. Gray -- not accepted
  Anaphalis occidentalis (Greene) A. Heller -- not accepted
  Ancistrocarphus A. Gray -- accepted -- woolly fishhooks, neststraw
  Ancistrocarphus filagineus A. Gray -- accepted -- hooded neststraw, false neststraw
  Ancistrocarphus keilii Morefield -- accepted
  Anisocarpus Nutt. -- accepted
  Anisocarpus madioides Nutt. -- accepted -- woodland madia
  Anisocarpus scabridus (Eastw.) B.G. Baldw. -- accepted -- leafy raillardiopsis
  Anisocoma Torr. & A. Gray -- accepted -- anisocoma
  Anisocoma acaulis Torr. & A. Gray -- accepted -- scalebud, scale bud
  Antennaria Gaertn. -- accepted -- pussytoes
  Antennaria acuminata Greene -- not accepted
  Antennaria acuta Rydb. -- not accepted
  Antennaria affinis Fernald -- not accepted
  Antennaria aizoides Greene -- not accepted
  Antennaria alaskana Malte -- not accepted
  Antennaria albescens (E.E. Nelson) Rydb. -- not accepted
  Antennaria albicans Fernald -- not accepted
  Antennaria alborosea A.E. Porsild ex Porsild -- not accepted
  Antennaria alpina (L.) Gaertn. -- accepted -- alpine pussytoes
  Antennaria alpina var. canescens (Lange) Trautv. -- not accepted
  Antennaria alpina var. compacta (Malte) S.L. Welsh -- not accepted
  Antennaria alpina var. friesiana Trautv. -- not accepted
  Antennaria alpina var. glabrata J. Vahl -- not accepted
  Antennaria alpina var. intermedia Rosenv. -- not accepted
  Antennaria alpina var. media (Greene) Jeps. -- not accepted
  Antennaria alpina var. megacephala (Fernald) S.L. Welsh -- not accepted
  Antennaria alpina var. scabra (Greene) Jeps. -- not accepted
  Antennaria alpina var. stenophylla A. Gray -- not accepted
  Antennaria alpina var. stolonifera (A.E. Porsild) S.L. Welsh -- not accepted
  Antennaria alpina var. ungavensis Fernald -- not accepted
  Antennaria ambigens (Greene) Fernald -- not accepted
  Antennaria ampla Bush -- not accepted
  Antennaria anaphaloides Rydb. -- accepted -- pearly pussytoes, pussytoes, tall everlasting
  Antennaria angustata Greene -- not accepted
  Antennaria angustiarum Lunell -- not accepted
  Antennaria angustifolia Ekman non Rydb. -- not accepted
  Antennaria angustifolia Rydb. -- not accepted
  Antennaria appendiculata Fernald -- not accepted
  Antennaria aprica Greene -- not accepted
  Antennaria aprica var. minuscula (B. Boivin) B. Boivin -- not accepted
  Antennaria arcuata Cronquist -- accepted -- box pussytoes
  Antennaria arenicola Malte -- not accepted
  Antennaria argentea Benth. -- accepted -- silver pussytoes, silvery pussytoes
  Antennaria argentea ssp. aberrans E.E. Nelson -- not accepted
  Antennaria arida E.E. Nelson -- not accepted
  Antennaria arida ssp. viscidula E.E. Nelson -- not accepted
  Antennaria arida var. humilis (Rydb.) E.E. Nelson -- not accepted
  Antennaria arkansana Greene -- not accepted
  Antennaria arnoglossa Greene -- not accepted
  Antennaria arnoglossa var. ambigens Greene -- not accepted
  Antennaria aromatica Evert -- accepted -- scented pussytoes
  Antennaria athabascensis Greene -- not accepted
  Antennaria atriceps Fernald -- not accepted
  Antennaria aureola Lunell -- not accepted
  Antennaria austromontana E.E. Nelson -- not accepted
  Antennaria bakeri Greene -- not accepted
  Antennaria bayardii Fernald -- not accepted
  Antennaria bifrons Greene -- not accepted
  Antennaria boecheriana A.E. Porsild -- not accepted
  Antennaria borealis Greene -- not accepted
  Antennaria bracteosa Rydb. -- not accepted
  Antennaria brainerdii Greene -- not accepted
  Antennaria breitungii A.E. Porsild -- not accepted
  Antennaria brevistyla Fernald -- not accepted
  Antennaria brunnescens Fernald -- not accepted
  Antennaria burwellensis Malte -- not accepted
  Antennaria callilepis Greene -- not accepted
  Antennaria calophylla Greene -- not accepted
  Antennaria campestris Rydb. -- not accepted
  Antennaria campestris var. athabascensis (Greene) B. Boivin -- not accepted
  Antennaria cana (Fernald & Wiegand) Fernald -- not accepted
  Antennaria canadensis Greene -- not accepted
  Antennaria candida Greene -- not accepted
  Antennaria canescens (Lange) Malte -- not accepted
  Antennaria canescens ssp. porsildii (Ekman) A. Löve & D. Löve -- not accepted
  Antennaria canescens var. pseudoporsildii Böcher -- not accepted
  Antennaria caroliniana Rydb. -- not accepted
  Antennaria carpatica Greene -- accepted
  Antennaria carpatica var. humilis Hook. -- not accepted
  Antennaria carpatica var. lanata Hook. -- not accepted
  Antennaria carpatica var. pulcherrima Hook. -- not accepted
  Antennaria caucasica Boriss. -- accepted
  Antennaria chelonica Lunell -- not accepted
  Antennaria chilensis Remy -- accepted
  Antennaria chlorantha Greene -- not accepted
  Antennaria columnaris Fernald -- not accepted
  Antennaria compacta Malte -- not accepted
  Antennaria concinna E.E. Nelson -- not accepted
  Antennaria concolor Piper -- not accepted
  Antennaria confinis Greene -- not accepted
  Antennaria confusa Fernald -- not accepted
  Antennaria congesta Malte -- not accepted
  Antennaria corymbosa E.E. Nelson -- accepted -- flat-top pussytoes, flattop pussytoes, meadow everlasting
  Antennaria crymophila A.E. Porsild -- not accepted
  Antennaria decipiens Greene -- not accepted
  Antennaria denikeana B. Boivin -- not accepted
  Antennaria densa Greene -- not accepted
  Antennaria densifolia A.E. Porsild -- accepted -- denseleaf pussytoes
  Antennaria dimorpha (Nutt.) Torr. & A. Gray -- accepted -- low pussytoes, low everlasting
  Antennaria dimorpha var. flagellaris A. Gray -- not accepted
  Antennaria dimorpha var. integra L.F. Hend. -- not accepted
  Antennaria dimorpha var. latisquama (Piper) M. Peck -- not accepted
  Antennaria dimorpha var. macrocephala D.C. Eaton -- not accepted
  Antennaria dioica (L.) Gaertn. -- accepted -- stoloniferous pussytoes
  Antennaria dioica var. corymbosa (E.E. Nelson) Jeps. -- not accepted
  Antennaria dioica var. hyperborea (D. Don) Greene -- not accepted
  Antennaria dioica var. kernensis Jeps. -- not accepted
  Antennaria dioica var. marginata (Greene) Jeps. -- not accepted
  Antennaria dioica var. rosea (Greene) D.C. Eaton -- not accepted
  Antennaria ekmaniana A.E. Porsild -- not accepted
  Antennaria elegans A.E. Porsild -- not accepted
  Antennaria ellyae A.E. Porsild -- not accepted
  Antennaria erosa Greene -- not accepted
  Antennaria eucosma Fernald & Wiegand -- not accepted -- Newfoundland pussytoes
  Antennaria exilis Greene -- not accepted
  Antennaria eximia Greene -- not accepted
  Antennaria fallax Greene -- not accepted
  Antennaria fallax var. calophylla (Greene) Fernald -- not accepted
  Antennaria farwellii Greene -- not accepted
  Antennaria fendleri Greene -- not accepted
  Antennaria fernaldiana Polunin -- not accepted
  Antennaria flagellaris (A. Gray) A. Gray -- accepted -- whip pussytoes, stoloniferous pussy-toes
  Antennaria flavescens Rydb. -- not accepted
  Antennaria foggii Fernald -- not accepted
  Antennaria foliacea var. humilis Rydb. -- not accepted
  Antennaria formosa Greene -- not accepted
  Antennaria friesiana (Trautv.) Ekman -- accepted -- Fries' pussytoes
  Antennaria friesiana ssp. alaskana (Malte) Hultén -- accepted -- Fries' pussytoes
  Antennaria friesiana ssp. compacta (Malte) Hultén -- not accepted
  Antennaria friesiana ssp. friesiana (Trautv.) Ekman -- accepted -- Fries' pussytoes
  Antennaria friesiana ssp. neoalaskana (A.E. Porsild) Bayer & Stebbins -- accepted -- Fries' pussytoes
  Antennaria friesiana var. megacephala (Fernald) Hultén -- not accepted
  Antennaria fusca E.E. Nelson -- not accepted
  Antennaria gaspensis (Fernald) Fernald -- not accepted
  Antennaria geyeri A. Gray -- accepted -- pinewoods pussytoes, Geyer's everlasting, mountain pussytoes
  Antennaria glabrata (J. Vahl) Greene -- not accepted
  Antennaria gormanii H. St. John -- not accepted
  Antennaria grandis (Fernald) House -- not accepted
  Antennaria greenei Bush -- not accepted
  Antennaria groenlandica A.E. Porsild -- not accepted
  Antennaria hansii Kern. -- not accepted
  Antennaria hendersonii Piper -- not accepted
  Antennaria holmii Greene -- not accepted
  Antennaria howellii Greene -- accepted -- Howell's pussytoes, small pussytoes
  Antennaria howellii ssp. canadensis (Greene) Bayer -- accepted -- Canadian pussytoes
  Antennaria howellii ssp. gaspensis (Fernald) Chmiel. -- not accepted
  Antennaria howellii ssp. howellii Greene -- accepted -- Howell's pussytoes
  Antennaria howellii ssp. neodioica (Greene) Bayer -- accepted -- Howell's pussytoes, small pussytoes
  Antennaria howellii ssp. petaloidea (Fernald) Bayer -- accepted -- small pussytoes
  Antennaria howellii var. athabascensis (Greene) B. Boivin -- not accepted
  Antennaria howellii var. campestris (Rydb.) B. Boivin -- not accepted
  Antennaria hudsonica Malte -- not accepted
  Antennaria hygrophila Greene -- not accepted
  Antennaria hyperborea D. Don -- not accepted
  Antennaria imbricata E.E. Nelson -- not accepted
  Antennaria incarnata A.E. Porsild -- not accepted
  Antennaria insularis Greene -- not accepted
  Antennaria intermedia (Rosenv.) A.E. Porsild -- not accepted
  Antennaria isolepis Greene -- not accepted
  Antennaria labradorica Nutt. -- not accepted
  Antennaria laingii A.E. Porsild -- not accepted
  Antennaria lanata (Hook.) Greene -- accepted -- woolly pussytoes
  Antennaria lanulosa Greene -- not accepted
  Antennaria latisquama Piper -- not accepted
  Antennaria latisquamea Greene -- not accepted
  Antennaria leontopodioides Cody -- not accepted
  Antennaria leuchippii Porsild -- not accepted
  Antennaria leucophaea Piper -- not accepted
  Antennaria longifolia Greene -- not accepted
  Antennaria longii Fernald -- not accepted
  Antennaria lunellii Greene -- not accepted
  Antennaria luzuloides Torr. & A. Gray -- accepted -- rush pussytoes
  Antennaria luzuloides ssp. aberrans (E.E. Nelson) Bayer & Stebbins -- accepted -- rush pussytoes, small head everlasting
  Antennaria luzuloides ssp. luzuloides Torr. & A. Gray -- accepted -- rush pussytoes
  Antennaria luzuloides var. argentea (Benth.) A. Gray -- not accepted
  Antennaria luzuloides var. microcephala (A. Gray) Cronquist -- not accepted
  Antennaria luzuloides var. oblanceolata (Rydb.) M. Peck -- not accepted
  Antennaria macrocephala (D.C. Eaton) Rydb. -- not accepted
  Antennaria maculata Greene -- not accepted
  Antennaria magellanica Sch. Bip. -- not accepted
  Antennaria manicouagana Landry -- not accepted
  Antennaria marginata Greene -- accepted -- whitemargin pussytoes
  Antennaria media Greene -- accepted -- Rocky Mountain pussytoes
  Antennaria media ssp. ciliata E.E. Nelson -- not accepted
  Antennaria media ssp. compacta (Malte) Chmiel. -- not accepted
  Antennaria media ssp. fusca (E.E. Nelson) Chmiel. -- not accepted
  Antennaria media ssp. pulchella (Greene) Chmiel. -- not accepted
  Antennaria megacephala Fernald -- not accepted
  Antennaria mesochora Greene -- not accepted
  Antennaria microcephala A. Gray -- not accepted
  Antennaria microphylla Rydb. -- accepted -- littleleaf pussytoes, Rocky Mountain pussytoes, smallleaf pussytoes, small leaf everlasting
  Antennaria minuscula B. Boivin -- not accepted
  Antennaria modesta Greene -- not accepted
  Antennaria monocephala DC. -- accepted -- pygmy pussytoes
  Antennaria monocephala (Torr. & A. Gray) Greene non Antennaria monocephala DC. -- not accepted
  Antennaria monocephala ssp. angustata (Greene) Hultén -- accepted -- pygmy pussytoes
  Antennaria monocephala ssp. monocephala DC. -- accepted -- pygmy pussytoes
  Antennaria monocephala ssp. philonipha (A.E. Porsild) Hultén -- not accepted
  Antennaria monocephala var. exilis (Greene) Hultén -- not accepted
  Antennaria mucronata E.E. Nelson -- not accepted
  Antennaria munda Fernald -- not accepted
  Antennaria nardina Greene -- not accepted
  Antennaria nebraskensis Greene -- not accepted
  Antennaria neglecta Greene -- accepted -- field pussytoes
  Antennaria neglecta ssp. howellii (Greene) Hultén -- not accepted
  Antennaria neglecta var. argillicola (Stebbins) Cronquist -- not accepted
  Antennaria neglecta var. athabascensis (Greene) Roy L. Taylor & MacBryde -- not accepted
  Antennaria neglecta var. attenuata (Fernald) Cronquist -- not accepted
  Antennaria neglecta var. campestris (Rydb.) Steyerm. -- not accepted
  Antennaria neglecta var. canadensis (Greene) Cronquist -- not accepted
  Antennaria neglecta var. gaspensis (Fernald) Cronquist -- not accepted
  Antennaria neglecta var. howellii (Greene) Cronquist -- not accepted
  Antennaria neglecta var. neodioica (Greene) Cronquist -- not accepted
  Antennaria neglecta var. petaloidea (Fernald) Cronquist -- not accepted
  Antennaria neglecta var. randii (Fernald) Cronquist -- not accepted
  Antennaria nemoralis Greene -- not accepted
  Antennaria neoalaskana A.E. Porsild -- not accepted
  Antennaria neodioica Greene -- not accepted
  Antennaria neodioica ssp. canadensis (Greene) Bayer & Stebbins -- not accepted
  Antennaria neodioica ssp. howellii (Greene) Bayer -- not accepted
  Antennaria neodioica ssp. petaloidea (Fernald) Bayer & Stebbins -- not accepted
  Antennaria neodioica var. attenuata Fernald -- not accepted
  Antennaria neodioica var. chlorantha (Greene) B. Boivin -- not accepted
  Antennaria neodioica var. chlorophylla Fernald -- not accepted
  Antennaria neodioica var. gaspensis Fernald -- not accepted
  Antennaria neodioica var. grandis Fernald -- not accepted
  Antennaria neodioica var. interjecta Fernald -- not accepted
  Antennaria neodioica var. petaloidea Fernald -- not accepted
  Antennaria neodioica var. randii (Fernald) B. Boivin -- not accepted
  Antennaria neodioica var. rupicola (Fernald) Fernald -- not accepted
  Antennaria nitens Greene -- not accepted
  Antennaria nitida Greene -- not accepted
  Antennaria oblanceolata Rydb. -- not accepted
  Antennaria oblancifolia E.E. Nelson -- not accepted
  Antennaria obovata E.E. Nelson -- not accepted
  Antennaria obtusata Greene -- not accepted
  Antennaria occidentalis Greene -- not accepted
  Antennaria oxyphylla Greene -- not accepted
  Antennaria pallida E.E. Nelson -- not accepted
  Antennaria parlinii Fernald -- accepted -- Parlin's pussytoes
  Antennaria parlinii ssp. fallax (Greene) Bayer & Stebbins -- accepted -- Parlin's pussytoes
  Antennaria parlinii ssp. parlinii Fernald -- accepted -- Parlin's pussytoes
  Antennaria parlinii var. arnoglossa (Greene) Fernald -- not accepted
  Antennaria parlinii var. farwellii (Greene) B. Boivin -- not accepted
  Antennaria parvifolia Nutt. -- accepted -- small-leaf pussytoes, smalleaf pussytoes, little-leaf pussytoes, Rocky Mountain pussytoes, small leaf pussytoes
  Antennaria parvifolia sensu Greene non Nutt. -- not accepted -- smallleaf pussytoes
  Antennaria parvifolia var. bracteosa (Rydb.) A. Nelson -- not accepted
  Antennaria parvula Greene -- not accepted
  Antennaria peasei Fernald -- not accepted
  Antennaria pedicellata Greene -- not accepted
  Antennaria pedunculata A.E. Porsild -- not accepted
  Antennaria peramoena Greene -- not accepted
  Antennaria petaloidea (Fernald) Fernald -- not accepted
  Antennaria petaloidea var. scariosa Fernald -- not accepted
  Antennaria petaloidea var. subcorymbosa (Fernald) Fernald -- not accepted
  Antennaria petasites Greene -- not accepted
  Antennaria petiolata Fernald -- not accepted
  Antennaria philonipha A.E. Porsild -- not accepted
  Antennaria pinetorum Greene -- not accepted
  Antennaria piperi Rydb. -- not accepted
  Antennaria plantaginifolia (L.) Richardson -- accepted -- woman's tobacco, plantainleaf pussytoes
  Antennaria plantaginifolia var. ambigens (Greene) Cronquist -- not accepted
  Antennaria plantaginifolia var. arnoglossa (Greene) Cronquist -- not accepted
  Antennaria plantaginifolia var. monocephala Torr. & A. Gray -- not accepted
  Antennaria plantaginifolia var. parlinii (Fernald) Cronquist -- not accepted
  Antennaria plantaginifolia var. petiolata (Fernald) A. Heller -- not accepted
  Antennaria porsildii Ekman -- not accepted
  Antennaria pulchella Greene -- accepted -- Sierra pussytoes, beautiful pussytoes
  Antennaria pulcherrima (Hook.) Greene -- accepted -- showy pussytoes
  Antennaria pulcherrima ssp. anaphaloides (Rydb.) W.A. Weber -- not accepted
  Antennaria pulcherrima ssp. eucosma (Fernald & Wiegand) R.J. Bayer -- accepted -- elegant pussy-toes
  Antennaria pulcherrima ssp. pulcherrima (Hook.) Greene -- accepted -- handsome pussy-toes, showy pussy-toes
  Antennaria pulcherrima var. anaphaloides (Rydb.) G.W. Douglas -- not accepted
  Antennaria pulcherrima var. angustisquama A.E. Porsild -- not accepted
  Antennaria pulcherrima var. sordida B. Boivin -- not accepted
  Antennaria pulvinata Greene -- not accepted
  Antennaria pulvinata ssp. albescens E.E. Nelson -- not accepted
  Antennaria pumila Greene -- not accepted
  Antennaria pygmaea Fernald -- not accepted
  Antennaria pyramidata Greene -- not accepted
  Antennaria racemosa Hook. -- accepted -- raceme pussytoes
  Antennaria randii Fernald -- not accepted
  Antennaria recurva Greene -- not accepted
  Antennaria reflexa E.E. Nelson -- not accepted
  Antennaria rhodantha Fernald -- not accepted
  Antennaria rhodanthus Suksd. -- not accepted
  Antennaria rosea Greene -- accepted -- rosy pussytoes, rosy pussy-toes
  Antennaria rosea ssp. arida (E.E. Nelson) Bayer -- accepted -- rosy pussytoes
  Antennaria rosea ssp. confinis (Greene) Bayer -- accepted -- rosy pussytoes
  Antennaria rosea ssp. divaricata E.E. Nelson -- not accepted
  Antennaria rosea ssp. pulvinata (Greene) Bayer -- accepted -- pulvinate pussytoes
  Antennaria rosea ssp. rosea Greene -- accepted -- rosy pussytoes
  Antennaria rosea var. angustifolia (Rydb.) E.E. Nelson -- not accepted
  Antennaria rosea var. imbricata (E.E. Nelson) E.E. Nelson -- not accepted
  Antennaria rosea var. nitida (Greene) Breitung -- not accepted
  Antennaria rosulata Rydb. -- accepted -- Kaibab pussytoes
  Antennaria rousseaui Porsild -- not accepted
  Antennaria rupicola Fernald -- not accepted
  Antennaria russellii B. Boivin -- not accepted
  Antennaria sansonii Greene -- not accepted
  Antennaria scabra Greene -- not accepted
  Antennaria scariosa E.E. Nelson -- not accepted
  Antennaria sedoides Greene -- not accepted
  Antennaria shumaginensis A.E. Porsild -- not accepted
  Antennaria sierrae-blancae Rydb. -- not accepted
  Antennaria soliceps S.F. Blake -- accepted -- Charleston Mountain pussytoes, Charleston Mountain everlasting
  Antennaria solitaria Rydb. -- accepted -- singlehead pussytoes
  Antennaria solstitialis Lunell -- not accepted
  Antennaria sordida Greene -- not accepted
  Antennaria sornborgeri Fernald -- not accepted
  Antennaria spathulata (Fernald) Fernald -- not accepted
  Antennaria speciosa Greene -- not accepted
  Antennaria stenolepis Greene -- not accepted
  Antennaria stenophylla (A. Gray) A. Gray -- accepted -- narrowleaf pussytoes, narrowleaf everlasting
  Antennaria stolonifera A.E. Porsild -- not accepted
  Antennaria straminea Fernald -- not accepted
  Antennaria subcanescens Ostenf. ex Malte -- not accepted
  Antennaria subviscosa Fernald -- not accepted
  Antennaria suffrutescens Greene -- accepted -- evergreen everlasting
  Antennaria tansleyi Polunin -- not accepted
  Antennaria tomentella E.E. Nelson -- not accepted
  Antennaria tweedsmurii Polunin -- not accepted
  Antennaria umbellata Greene -- not accepted
  Antennaria umbrinella Rydb. -- accepted -- umber pussytoes, brown everlasting
  Antennaria umbrinella auct. non Rydb. -- not accepted
  Antennaria ungavensis (Fernald) Malte -- not accepted
  Antennaria vexillifera Fernald -- not accepted
  Antennaria virginica Stebbins -- accepted -- shale barren pussytoes, shalebarren pussytoes
  Antennaria virginica var. argillicola Stebbins -- not accepted
  Antennaria wiegandii Fernald -- not accepted
  Antennaria wilsonii Greene -- not accepted
  Antennaria X erigeroides Greene -- accepted -- erigeron pussytoes
  Antennaria X foliacea Greene (pro sp.) -- accepted -- foliaceous pussytoes
  Antennaria X macounii Greene (pro sp.) -- accepted
  Antennaria X oblancifolia E.E. Nelson (pro sp.) -- accepted -- pussytoes
  Anthemis L. -- accepted -- chamomile
  Anthemis altissima L. -- accepted -- tall chamomile
  Anthemis arvensis L. -- accepted -- corn chamomile, scentless chamomile, mayweed
  Anthemis arvensis var. agrestis (Wallr.) DC. -- not accepted -- corn chamomile
  Anthemis arvensis var. arvensis L. -- not accepted -- corn chamomile
  Anthemis austriaca Jacq. -- accepted -- Austrian chamomile
  Anthemis cotula L. -- accepted -- stinking chamomile, dogfennel, mayweed, mayweed dogfennel, dog fennel, mayweed chamomile, stinkweed, chamomile
  Anthemis fuscata Brot. -- not accepted
  Anthemis mixta L. -- not accepted
  Anthemis nobilis L. -- not accepted
  Anthemis secundiramea Biv. -- accepted -- prostrate chamomile
  Anthemis tinctoria L. -- not accepted -- golden chamomile
  Antheropeas Rydb. -- accepted -- easterbonnets, easter-bonnets
  Antheropeas lanosum (A. Gray) Rydb. -- not accepted -- white easterbonnets, white easter-bonnets
  Antheropeas wallacei (A. Gray) Rydb. -- not accepted -- woolly easterbonnets, woolly easter-bonnets, Wallace's woolydaisy
  Apargia autumnalis (L.) Hoffm. -- not accepted
  Apargia hispida (L.) Willd. -- not accepted
  Apargia nudicaulis (L.) Britton -- not accepted
  Apargidium Torr. & A. Gray -- not accepted
  Apargidium boreale (Bong.) Torr. & A. Gray -- not accepted
  Aphanostephus DC. -- accepted -- dozedaisy, doze daisy
  Aphanostephus arizonicus A. Gray -- not accepted
  Aphanostephus humilis (Benth.) A. Gray -- not accepted
  Aphanostephus kidderi S.F. Blake -- not accepted
  Aphanostephus pilosus Buckley -- accepted -- hairy dozedaisy
  Aphanostephus potosinus Shinners -- not accepted
  Aphanostephus ramosissimus DC. -- accepted -- plains dozedaisy
  Aphanostephus ramosissimus var. humilis (Benth.) B.L. Turner & Birdsong -- accepted -- plains dozedaisy, plains doze daisy
  Aphanostephus ramosissimus var. ramosissimus DC. -- accepted -- plains dozedaisy
  Aphanostephus riddellii Torr. & A. Gray -- accepted -- Riddell's dozedaisy
  Aphanostephus skirrhobasis (DC.) Trel. -- accepted -- Arkansas dozedaisy
  Aphanostephus skirrhobasis var. kidderi (S.F. Blake) B.L. Turner -- accepted -- Arkansas dozedaisy
  Aphanostephus skirrhobasis var. skirrhobasis (DC.) Trel. -- accepted -- Arkansas dozedaisy
  Aphanostephus skirrhobasis var. thalassius Shinners -- accepted -- Arkansas dozedaisy
  Aphantochaeta exilis A. Gray -- not accepted
  Aplopappus sphaerocephalus Harv. & A. Gray ex A. Gray -- not accepted
  Aplopappus tortifolius Torr. & A. Gray -- not accepted
  Arctanthemum (Tzvelev) Tzvelev -- accepted
  Arctanthemum arcticum (L.) Tzvelev -- accepted -- arctic daisy
  Arctanthemum arcticum ssp. arcticum (L.) Tzvelev -- accepted -- arctic daisy
  Arctanthemum arcticum ssp. polare (Hultén) Tzvelev -- accepted -- arctic daisy
  Arctanthemum integrifolium (Richardson) Tzvelev -- not accepted
  Arctium L. -- accepted -- burdock, burrdock
  Arctium lappa L. -- accepted -- greater burdock, woodland burdock, bardane, great burdock, greater burrdock
  Arctium minus Bernh. -- accepted -- lesser burdock, lesser burrdock, burdock, small burdock, smaller burdock, bardane, beggar's button, common burdock, wild burdock, wild rhubarb
  Arctium minus ssp. nemorosum (Lej. & Court.) Syme -- not accepted
  Arctium nemorosum Lej. & Court. -- not accepted
  Arctium tomentosum Mill. -- accepted -- woolly burdock, woolly burrdock
  Arctium vulgare (Hill) Evans -- not accepted -- woodland burrdock
  Arctium X mixtum Nyman -- accepted -- burrdock
  Arctium X nothum (Ruhmer) J. Weiss -- accepted -- burrdock
  Arctotheca J.C. Wendl. -- accepted -- Capeweed
  Arctotheca calendula (L.) Levyns -- accepted -- Capeweed, Cape weed
  Arctotis L. -- accepted -- arctotis
  Arctotis fastuosa Jacq. -- accepted -- monarch-of-the-veld
  Arctotis grandis Thunb. -- not accepted
  Arctotis stoechadifolia P.J. Bergius -- accepted -- African daisy
  Arctotis stoechadifolia var. grandis (Thunb.) Less. -- not accepted
  Argyranthemum Webb -- accepted -- dill daisy
  Argyranthemum anethifolium (Willd.) Webb -- not accepted
  Argyranthemum foeniculum (Willd.) Sch. Bip. -- accepted -- dill daisy
  Argyranthemum frutescens (L.) Sch. Bip. -- accepted -- marguerite
  Argyranthemum gracilis Webb ex Sch. Bip. -- accepted -- Tenerife white marguerite
  Argyroxiphium DC. -- accepted -- silversword
  Argyroxiphium caliginis Forbes -- accepted -- eke silversword
  Argyroxiphium caliginis var. kai Forbes -- not accepted
  Argyroxiphium forbesii H. St. John -- not accepted
  Argyroxiphium grayanum (Hillebr.) O. Deg. -- accepted -- Hana Forest silversword
  Argyroxiphium kauense (Rock & Neal) O. Deg. & I. Deg. -- accepted -- Ka'u silversword, Kau silversword, Mauna Loa silversword
  Argyroxiphium macrocephalum A. Gray -- not accepted
  Argyroxiphium sandwicense DC. -- accepted -- Hawai'i silversword
  Argyroxiphium sandwicense ssp. macrocephalum (A. Gray) Mérat -- accepted -- Hawai'i silversword, `ahinahina, Haleakala silversword
  Argyroxiphium sandwicense ssp. sandwicense DC. -- accepted -- Hawai'i silversword, `ahinahina, Mauna Kea silversword
  Argyroxiphium sandwicense var. kauense Rock & Neal -- not accepted
  Argyroxiphium virescens Hillebr. -- accepted -- greensword
  Argyroxiphium X kai (Forbes) D.D. Keck -- accepted -- kai silversword
  Arida (R.L.Hartm.) D.R.Morgan & R.L.Hartm. -- accepted
  Arida arizonica (R.C. Jacks. & R.R. Johnson) D.R. Morgan & R.L. Hartm. -- accepted -- desert tansy-aster, arid tansyaster
  Arida blepharophylla (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted -- gypsum tansy-aster
  Arida carnosa (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted -- shrubby alkali tansy-aster, shrubby alkaliaster
  Arida mattturneri B.L. Turner & G.L. Nesom -- accepted
  Arida parviflora (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted -- small-flower tansy-aster
  Arida riparia (Kunth) D.R. Morgan & R.L. Hartm. -- accepted -- Chiricahua mountain tansy-aster, alkali aster
  Arnica L. -- accepted -- arnica
  Arnica acaulis (Walter) Britton, Sterns & Poggenb. -- accepted -- common leopardbane
  Arnica alpina (L.) Olin -- accepted -- alpine arnica
  Arnica alpina ssp. angustifolia (Vahl) Maguire -- not accepted
  Arnica alpina ssp. attenuata (Greene) Maguire -- not accepted
  Arnica alpina ssp. lonchophylla (Greene) Roy L. Taylor & MacBryde -- not accepted
  Arnica alpina ssp. sornborgeri (Fernald) Maguire -- not accepted
  Arnica alpina ssp. tomentosa (Macoun) Maguire -- not accepted
  Arnica alpina var. angustifolia (Vahl) Fernald -- not accepted
  Arnica alpina var. attenuata (Greene) Ediger & T.M. Barkley -- not accepted
  Arnica alpina var. linearis Hultén -- not accepted
  Arnica alpina var. lonchophylla (Greene) S.L. Welsh -- not accepted
  Arnica alpina var. plantaginea (Pursh) Ediger & T.M. Barkley -- not accepted
  Arnica alpina var. tomentosa (Macoun) Cronquist -- not accepted
  Arnica alpina var. ungavensis B. Boivin -- not accepted
  Arnica alpina var. vestita Hultén -- not accepted
  Arnica amplexicaulis Nutt. -- not accepted -- clasping arnica, streambank arnica
  Arnica amplexicaulis ssp. genuina Maguire -- not accepted
  Arnica amplexicaulis ssp. prima (Maguire) Maguire -- not accepted
  Arnica amplexicaulis var. piperi H. St. John & Warren -- not accepted
  Arnica amplexicaulis var. prima (Maguire) B. Boivin -- not accepted
  Arnica amplexifolia Rydb. -- not accepted
  Arnica angustifolia Vahl -- accepted -- narrowleaf arnica
  Arnica angustifolia ssp. angustifolia Vahl -- accepted -- narrowleaf arnica
  Arnica angustifolia ssp. attenuata (Greene) G.W. Douglas -- not accepted
  Arnica angustifolia ssp. lonchophylla (Greene) G.W. Douglas & G. Ruyle-Douglas -- not accepted
  Arnica angustifolia ssp. tomentosa (Macoun) G.W. Douglas & G. Ruyle-Douglas -- accepted -- narrowleaf arnica
  Arnica angustifolia var. tomentosa (Macoun) Dorn -- not accepted
  Arnica arnoglossa Greene -- not accepted
  Arnica bernardina Greene -- not accepted
  Arnica cascadensis H. St. John -- not accepted
  Arnica cernua Howell -- accepted -- serpentine arnica
  Arnica chamissonis Less. -- accepted -- Chamisso arnica
  Arnica chamissonis ssp. chamissonis Less. -- not accepted -- Chamisso arnica
  Arnica chamissonis ssp. chamissonis var. chamissonis Less. -- not accepted -- Chamisso arnica
  Arnica chamissonis ssp. chamissonis var. interior Maguire -- not accepted -- Chamisso arnica
  Arnica chamissonis ssp. foliosa (Nutt.) Maguire -- not accepted -- Chamisso arnica, arnica de Chamisso sous-espčce multifeuille
  Arnica chamissonis ssp. foliosa var. andina (Nutt.) Ediger & T.M. Barkley -- not accepted -- Chamisso arnica
  Arnica chamissonis ssp. foliosa var. bernardina (Greene) Maguire -- not accepted -- Chamisso arnica
  Arnica chamissonis ssp. foliosa var. incana (A. Gray) Hultén -- not accepted -- Chamisso arnica, hoary arnica
  Arnica chamissonis ssp. foliosa var. maguirei (A. Nelson) Maguire -- not accepted -- Chamisso arnica
  Arnica chamissonis ssp. genuina Maguire -- not accepted
  Arnica chamissonis ssp. incana (A. Gray) Maguire -- not accepted
  Arnica chamissonis var. andina (Nutt.) Ediger & T.M. Barkl. -- not accepted -- Chamisso arnica
  Arnica chamissonis var. bernardina (Greene) Maguire -- not accepted -- Chamisso arnica
  Arnica chamissonis var. chamissonis Less. -- not accepted -- Chamisso arnica
  Arnica chamissonis var. foliosa (Nutt.) Maguire -- not accepted
  Arnica chamissonis var. incana (Gray) Hultén -- not accepted -- Chamisso arnica
  Arnica chamissonis var. interior Maguire -- not accepted -- Chamisso arnica
  Arnica chamissonis var. jepsoniana Maguire -- not accepted
  Arnica chamissonis var. maguirei (A. Nels.) Maguire -- not accepted -- Chamisso arnica
  Arnica chandleri Rydb. -- not accepted
  Arnica chionopappa Fernald -- not accepted
  Arnica cordifolia Hook. -- accepted -- heartleaf arnica, heart-leaf leopardbane
  Arnica cordifolia ssp. genuina Maguire -- not accepted
  Arnica cordifolia var. humilis (Rydb.) Maguire -- not accepted
  Arnica cordifolia var. pumila (Rydb.) Maguire -- not accepted
  Arnica cordifolia var. whitneyi (Fernald) Maguire -- not accepted
  Arnica cusickii Rydb. -- not accepted
  Arnica dealbata (A. Gray) B.G. Baldw. -- accepted -- mock leopardbane
  Arnica discoidea Benth. -- accepted -- rayless arnica
  Arnica discoidea var. alata (Rydb.) Cronquist -- not accepted
  Arnica discoidea var. eradiata (A. Gray) Cronquist -- not accepted
  Arnica foliosa Nutt. -- not accepted
  Arnica foliosa var. incana A. Gray -- not accepted
  Arnica frigida C.A. Mey. ex Iljin -- not accepted -- snow arnica
  Arnica frigida ssp. frigida C.A. Mey. ex Iljin -- not accepted -- snow arnica
  Arnica frigida ssp. griscomii (Fernald) S.R. Downie -- not accepted -- Griscom's arnica
  Arnica frigida var. glandulosa B. Boivin -- not accepted
  Arnica fulgens Pursh -- accepted -- foothill arnica, orange arnica, shining leopardbane
  Arnica fulgens var. sororia (Greene) G.W. Douglas & G. Ruyle-Douglas -- not accepted
  Arnica gaspensis Fernald -- not accepted
  Arnica gracilis Rydb. -- accepted -- smallhead arnica
  Arnica grayi A. Heller -- not accepted
  Arnica griscomii Fernald -- accepted
  Arnica griscomii ssp. frigida (C.A. Mey. ex Iljin) S.J. Wolf -- accepted -- snow arnica
  Arnica griscomii ssp. griscomii Fernald -- accepted
  Arnica hardinae H. St. John -- not accepted
  Arnica humilis Rydb. -- not accepted
  Arnica lanceolata Nutt. -- accepted -- lanceleaf arnica, arnica, arnica ŕ aigrettes brunes
  Arnica lanceolata ssp. lanceolata Nutt. -- accepted -- lanceleaf arnica, arnica ŕ aigrettes brunes
  Arnica lanceolata ssp. prima (Maguire) Strother & S.J. Wolf -- accepted -- clasping arnica
  Arnica latifolia Bong. -- accepted -- broadleaf arnica
  Arnica latifolia var. angustifolia Herder -- not accepted
  Arnica latifolia var. gracilis (Rydb.) Cronquist -- not accepted
  Arnica lessingii Greene -- accepted -- nodding arnica
  Arnica lessingii ssp. norbergii Hultén & Maguire -- not accepted
  Arnica lonchophylla Greene -- accepted -- longleaf arnica, seep arnica
  Arnica lonchophylla ssp. arnoglossa (Greene) Maguire -- not accepted -- seep arnica
  Arnica lonchophylla ssp. chionopappa (Fernald) Maguire -- not accepted
  Arnica lonchophylla ssp. lonchophylla Greene -- not accepted -- longleaf arnica, arnica lonchophylle sous-espčce lonchophylle
  Arnica lonchophylla var. arnoglossa (Greene) B. Boivin -- not accepted
  Arnica longifolia D.C. Eaton -- accepted -- spearleaf arnica, longleaf arnica
  Arnica longifolia ssp. genuina Maguire -- not accepted
  Arnica longifolia ssp. myriadenia (Piper) Maguire -- not accepted
  Arnica louiseana Farr -- accepted -- Lake Louise arnica
  Arnica louiseana ssp. frigida (C.A. Mey. ex Iljin) Maguire -- not accepted
  Arnica louiseana ssp. griscomii (Fernald) Maguire -- not accepted
  Arnica louiseana var. brevifolia (Rydb.) Maguire -- not accepted
  Arnica louiseana var. frigida (C.A. Mey. ex Iljin) S.L. Welsh -- not accepted
  Arnica louiseana var. genuina Maguire -- not accepted
  Arnica louiseana var. griscomii (Fernald) Boivin -- not accepted
  Arnica louiseana var. illiamnae (Rydb.) Maguire -- not accepted
  Arnica louiseana var. mendenhallii (Rydb.) Maguire -- not accepted
  Arnica louiseana var. pilosa Maguire -- not accepted
  Arnica mollis Hook. -- accepted -- hairy arnica, wooly arnica
  Arnica mollis var. aspera (Greene) B. Boivin -- not accepted
  Arnica mollis var. petiolaris Fernald -- not accepted
  Arnica mollis var. silvatica (Greene) Maguire -- not accepted
  Arnica montana L. -- accepted -- mountain arnica
  Arnica nevadensis A. Gray -- accepted -- Nevada arnica
  Arnica ovata Greene -- accepted -- sticky leaf arnica, rayless arnica
  Arnica paniculata A. Nelson -- not accepted
  Arnica parryi A. Gray -- accepted -- Parry's arnica, Sonne's arnica, nodding arnica
  Arnica parryi ssp. genuina Maguire -- not accepted
  Arnica parryi ssp. parryi A. Gray -- not accepted -- Parry's arnica
  Arnica parryi ssp. sonnei (Greene) Maguire -- not accepted -- Sonne's arnica
  Arnica parryi var. sonnei (Greene) Cronquist -- not accepted
  Arnica parviflora A. Gray -- not accepted
  Arnica parviflora ssp. alata (Rydb.) Maguire -- not accepted
  Arnica plantaginea Pursh -- not accepted
  Arnica rydbergii Greene -- accepted -- Rydberg's arnica, subalpine arnica
  Arnica snyderi Raup -- not accepted
  Arnica sonnei Greene -- not accepted
  Arnica sornborgeri Fernald -- not accepted
  Arnica sororia Greene -- accepted -- twin arnica
  Arnica spathulata Greene -- accepted -- Klamath arnica
  Arnica spathulata ssp. eastwoodiae (Rydb.) Maguire -- not accepted
  Arnica spathulata var. eastwoodiae (Rydb.) Ediger & T.M. Barkley -- not accepted
  Arnica terrae-novae Fernald -- not accepted
  Arnica tomentella Greene -- not accepted
  Arnica tomentosa Macoun -- not accepted
  Arnica unalaschcensis Less. -- accepted -- Alaska arnica
  Arnica venosa H.M. Hall -- accepted -- Shasta County arnica
  Arnica viscosa A. Gray -- accepted -- Mt. Shasta arnica
  Arnica whitneyi Fernald -- not accepted
  Arnica X diversifolia Greene (pro sp.) -- not accepted -- rayless arnica, Curtis churchmouse threeawn, sticky arnica
  Arnoglossum Raf. -- accepted -- Indian plantain, Indian plaintain, arnoglossum
  Arnoglossum album L.C. Anderson -- accepted -- Bay County Indian plantain
  Arnoglossum atriplicifolium (L.) H. Rob. -- accepted -- pale Indian plantain, pale Indian plaintain
  Arnoglossum diversifolium (Torr. & A. Gray) H. Rob. -- accepted -- variableleaf Indian plantain, variableleaf Indian plaintain
  Arnoglossum floridanum (A. Gray) H. Rob. -- accepted -- Florida cacalia
  Arnoglossum muehlenbergii (Sch. Bip.) H. Rob. -- not accepted -- great Indian plaintain
  Arnoglossum ovatum (Walter) H. Rob. -- accepted -- ovateleaf cacalia
  Arnoglossum plantagineum Raf. -- accepted -- groovestem Indian plantain, arnoglossum
  Arnoglossum reniforme (Hook.) H. Rob. -- accepted -- great Indian plantain
  Arnoglossum sulcatum (Fernald) H. Rob. -- accepted -- Georgia Indian plantain, Georgia Indian plaintain
  Arnoseris Gaertn. -- accepted -- arnoseris
  Arnoseris minima (L.) Schweigg. & Körte -- accepted -- lamb succory
  Artemisia L. -- accepted -- sagebrush, wormwood, sagewort
  Artemisia abrotanum L. -- accepted -- southernwood
  Artemisia absinthium L. -- accepted -- absinthium, absinth wormwood, absinth sagewort, common sagewort
  Artemisia absinthium var. absinthium L. -- not accepted -- absinth sagewort
  Artemisia absinthium var. insipida Stechmann -- not accepted -- insipid absinth
  Artemisia alaskana Rydb. -- accepted -- Alaska wormwood
  Artemisia albula Woot. -- not accepted
  Artemisia aleutica Hultén -- accepted -- Aleutian wormwood
  Artemisia angusta Rydb. -- not accepted
  Artemisia angustifolia (Gray) Rydb. -- not accepted
  Artemisia annua L. -- accepted -- sweet sagewort, annual wormwood
  Artemisia arbuscula Nutt. -- accepted -- little sagebrush, low sagebrush
  Artemisia arbuscula ssp. arbuscula Nutt. -- accepted -- gray low sagebrush, little sagebrush
  Artemisia arbuscula ssp. longicaulis Winward & McArthur -- accepted -- little sagebrush, Lahontan sagebrush
  Artemisia arbuscula ssp. longiloba (Osterh.) L.M. Shultz -- accepted -- alkali sagebrush, early sagebrush, little sagebrush
  Artemisia arbuscula ssp. nova (A. Nelson) G.H. Ward -- not accepted
  Artemisia arbuscula ssp. thermopola Beetle -- accepted -- little sagebrush
  Artemisia arbuscula var. longiloba (Osterh.) Dorn -- not accepted
  Artemisia arbuscula var. nova (A. Nelson) Cronquist -- not accepted
  Artemisia arctica Less. -- not accepted -- boreal sagebrush
  Artemisia arctica ssp. arctica Less. -- not accepted -- boreal sagebrush
  Artemisia arctica ssp. beringensis (Hultén) Hultén -- not accepted -- boreal sagebrush
  Artemisia arctica ssp. comata (Rydb.) Hultén -- not accepted -- boreal sagebrush
  Artemisia arctica ssp. saxicola (Rydb.) Hultén -- not accepted -- arctic wormwood
  Artemisia arctica var. beringensis Hultén -- not accepted
  Artemisia argentea L'Hér. -- accepted
  Artemisia argilosa Beetle -- not accepted
  Artemisia aucheri Boiss. -- accepted
  Artemisia australis Less. -- accepted -- Oahu wormwood
  Artemisia biennis Willd. -- accepted -- biennial wormwood, biennial sagewort
  Artemisia biennis var. biennis Willd. -- not accepted -- biennial wormwood
  Artemisia biennis var. diffusa Dorn -- not accepted -- biennial wormwood
  Artemisia bigelovii A. Gray -- accepted -- Bigelow sage, Bigelow sagebrush, Bigelow's sagebrush
  Artemisia bolanderi A. Gray -- not accepted
  Artemisia borealis Pall. -- accepted -- field sagewort
  Artemisia borealis ssp. borealis Pall. -- accepted
  Artemisia borealis ssp. purshii (Hook.) Hultén -- not accepted
  Artemisia borealis ssp. richardsoniana (Besser) Korobkov -- accepted
  Artemisia borealis var. latisecta Fernald -- not accepted
  Artemisia borealis var. purshii Hook. -- not accepted
  Artemisia californica Less. -- accepted -- coastal sagebrush
  Artemisia californica var. insularis (Rydb.) Munz -- not accepted
  Artemisia campestris L. -- accepted -- Pacific wormwood, wormwood sagewort, common sagewort, field sagewort
  Artemisia campestris ssp. borealis (Pall.) H.M. Hall & Clem. -- not accepted -- field sagewort, northern sagewort
  Artemisia campestris ssp. borealis var. borealis (Pall.) M. Peck -- not accepted -- field sagewort
  Artemisia campestris ssp. borealis var. petiolata S.L. Welsh -- not accepted
  Artemisia campestris ssp. borealis var. purshii (Hook.) Cronq. -- not accepted -- Pursh's wormwood
  Artemisia campestris ssp. borealis var. wormskioldii (Besser ex Hook.) Cronquist -- not accepted -- field sagewort
  Artemisia campestris ssp. campestris L. -- accepted -- field wormwood, field sagewort
  Artemisia campestris ssp. canadensis (Michx.) Scoggan -- accepted
  Artemisia campestris ssp. caudata (Michx.) H.M. Hall & Clem. -- accepted -- Pacific wormwood, field wormwood, field sagewort
  Artemisia campestris ssp. glutinosa (J. Gay ex Besser) Batt. -- accepted
  Artemisia campestris ssp. pacifica (Nutt.) H.M. Hall & Clem. -- accepted -- Pacific wormwood, western sagewort, field sagewort
  Artemisia campestris var. borealis (Pall.) M. Peck -- not accepted -- field sagewort
  Artemisia campestris var. canadensis (Michx.) S.L. Welsh -- not accepted
  Artemisia campestris var. caudata (Michx.) Palmer & Steyerm. -- not accepted
  Artemisia campestris var. douglasiana (Besser) B. Boivin -- not accepted
  Artemisia campestris var. pacifica (Nutt.) M. Peck -- not accepted
  Artemisia campestris var. petiolata Welsh -- not accepted -- field sagewort
  Artemisia campestris var. purshii (Hook.) Cronquist -- not accepted
  Artemisia campestris var. scouleriana (Hook.) Cronq. -- not accepted -- field sagewort
  Artemisia campestris var. strutziae S.L. Welsh -- not accepted
  Artemisia campestris var. wormskioldii (Besser ex Hook.) Cronquist -- not accepted -- northern wormwood, field sagewort
  Artemisia camporum Rydb. -- not accepted
  Artemisia cana Pursh -- accepted -- silver sagebrush
  Artemisia cana ssp. bolanderi (A. Gray) G.H. Ward -- accepted -- silver sagebrush, Bolander's silver sagebrush
  Artemisia cana ssp. cana Pursh -- accepted -- silver sagebrush, Coaltown sagebrush
  Artemisia cana ssp. viscidula (Osterh.) Beetle -- accepted -- Coaltown sagebrush, mountain silver sagebrush, silver sagebrush
  Artemisia cana var. cana Pursh -- not accepted
  Artemisia cana var. viscidula Osterh. -- not accepted
  Artemisia canadensis Michx. -- not accepted
  Artemisia canariensis (Besser) Less. -- not accepted
  Artemisia candicans Rydb. -- not accepted
  Artemisia carruthii Alph. Wood ex Carruth. -- accepted -- Carruth's sagewort, Carruth's sagebrush
  Artemisia carruthii var. wrightii (A. Gray) S.F. Blake -- not accepted
  Artemisia caucasica Willd. -- not accepted
  Artemisia caudata Michx. -- not accepted
  Artemisia caudata var. calvens Lunell -- not accepted
  Artemisia chamaemelifolia Vill. -- accepted
  Artemisia cina O. Berg & C.F. Schmidt -- accepted -- santonica
  Artemisia comata Rydb. -- not accepted
  Artemisia diversifolia Rydb. -- not accepted
  Artemisia douglasiana Besser -- accepted -- Douglas' sagewort, Douglas' mugwort
  Artemisia dracunculoides Pursh -- not accepted
  Artemisia dracunculoides var. dracunculina (S. Watson) S.F. Blake -- not accepted
  Artemisia dracunculus L. -- accepted -- tarragon, green sagewort, wormwood, false tarragon, silky wormwood
  Artemisia dracunculus ssp. dracunculus L. -- not accepted -- wormwood
  Artemisia dracunculus ssp. glauca (Pall. ex Willd.) H.M. Hall & Clem. -- not accepted -- dragon wormwood
  Artemisia dracunculus var. glauca (Pall. ex Willd.) Besser -- not accepted
  Artemisia elatior (Torr. & A. Gray) Rydb. -- not accepted
  Artemisia filifolia Torr. -- accepted -- sand sagebrush, sandhill sage, silvery wormwood
  Artemisia flava Jurtzev -- not accepted
  Artemisia forwoodii S. Watson -- not accepted
  Artemisia franserioides Greene -- accepted -- ragweed sagebrush
  Artemisia frigida Willd. -- accepted -- prairie sagewort, fringed sagewort, fringed sagebrush
  Artemisia frigida var. williamsiae S.L. Welsh -- not accepted
  Artemisia furcata M. Bieb. -- accepted -- forked wormwood
  Artemisia furcata var. furcata M. Bieb. -- not accepted -- forked wormwood
  Artemisia furcata var. heterophylla (Besser) Hultén -- not accepted -- forked wormwood
  Artemisia glauca Pall. ex Willd. -- not accepted
  Artemisia glauca var. dracunculina (S. Watson) Fernald -- not accepted
  Artemisia globularia Cham. ex Besser -- accepted -- purple wormwood
  Artemisia globularia var. lutea Hultén -- not accepted
  Artemisia glomerata Ledeb. -- accepted -- Pacific alpine wormwood, cudweed sagewort
  Artemisia glomerata var. glomerata Ledeb. -- not accepted -- Pacific alpine wormwood
  Artemisia glomerata var. subglabrata Hultén -- not accepted -- Pacific alpine wormwood
  Artemisia gmelinii Webb ex Stechmann -- accepted -- Gmelin's wormwood
  Artemisia gnaphalodes Nutt. -- not accepted
  Artemisia gorgonum Webb -- accepted
  Artemisia gormanii Rydb. -- not accepted
  Artemisia herba-alba Asso -- accepted -- white wormwood
  Artemisia herriotii Rydb. -- not accepted
  Artemisia heterophylla Besser -- not accepted
  Artemisia hillebrandii Skottsb. -- not accepted
  Artemisia hillebrandii var. kauaiensis Skottsb. -- not accepted
  Artemisia hookeriana Besser -- not accepted -- Hooker's sagebrush
  Artemisia hyperborea Rydb. -- not accepted
  Artemisia incompta Nutt. -- not accepted
  Artemisia kansana Britton -- not accepted
  Artemisia kauaiensis (Skottsb.) Skottsb. -- accepted -- Kauai wormwood
  Artemisia krushiana Bess -- accepted -- Krush's wormwood
  Artemisia laciniata Willd. -- accepted -- Siberian wormwood
  Artemisia laciniata ssp. laciniata Willd. -- accepted -- Yukon wormwood
  Artemisia laciniata ssp. parryi (A. Gray) W.A. Weber -- accepted -- Parry's wormwood
  Artemisia laciniatiformis Kom. -- not accepted
  Artemisia laxa (Lam.) Fritsch -- not accepted
  Artemisia lindleyana Besser -- not accepted -- Columbia River wormwood
  Artemisia longifolia Nutt. -- accepted -- longleaf wormwood, longleaf sagebrush
  Artemisia longiloba (Osterh.) Beetle -- not accepted
  Artemisia ludoviciana Nutt. -- accepted -- white sagebrush, cudweed sagewort, Louisiana sagewort, gray sagewort, Louisiana wormwood, mugwort wormwood, prairie sage
  Artemisia ludoviciana ssp. albula (Woot.) D.D. Keck -- accepted -- white sagebrush, gray sagewort, white sagewort
  Artemisia ludoviciana ssp. candicans (Rydb.) D.D. Keck -- accepted -- gray sagewort, white sagebrush
  Artemisia ludoviciana ssp. estesii K.L. Chambers -- accepted -- white sagebrush
  Artemisia ludoviciana ssp. incompta (Nutt.) D.D. Keck -- accepted -- mountain sagewort, white sagebrush, Columbia River wormwood
  Artemisia ludoviciana ssp. ludoviciana Nutt. -- accepted -- white sagebrush, cudweed sagewort, foothill sagewort, Louisiana sagewort
  Artemisia ludoviciana ssp. mexicana (Willd. ex Spreng.) D.D. Keck -- accepted -- cudweed sagewort, Louisiana sagewort, Mexican white sagebrush, Mexican sagewort, white sagebrush
  Artemisia ludoviciana ssp. redolens (A. Gray) D.D. Keck -- accepted -- white sagebrush, white sagewort
  Artemisia ludoviciana ssp. sulcata (Rydb.) D.D. Keck -- accepted -- white sagebrush, green sagewort
  Artemisia ludoviciana ssp. typica D.D. Keck -- not accepted
  Artemisia ludoviciana var. albula (Woot.) Shinners -- not accepted
  Artemisia ludoviciana var. americana (Besser) Fernald -- not accepted
  Artemisia ludoviciana var. brittonii (Rydb.) Fernald -- not accepted
  Artemisia ludoviciana var. gnaphalodes (Nutt.) Torr. & A. Gray -- not accepted
  Artemisia ludoviciana var. incompta (Nutt.) Cronquist -- not accepted
  Artemisia ludoviciana var. latifolia (Besser) Torr. & A. Gray -- not accepted
  Artemisia ludoviciana var. latiloba Nutt. -- not accepted
  Artemisia ludoviciana var. mexicana (Willd. ex Spreng.) A. Gray -- not accepted
  Artemisia ludoviciana var. pabularis (A. Nelson) Fernald -- not accepted
  Artemisia ludoviciana var. redolens (A. Gray) Shinners -- not accepted
  Artemisia macrobotrys Ledeb. -- not accepted -- Yukon wormwood
  Artemisia maritima L. -- accepted -- sea wormwood
  Artemisia matricarioides auct. non Less. -- not accepted
  Artemisia mauiensis (A. Gray) Skottsb. -- accepted -- Maui wormwood
  Artemisia mauiensis var. diffusa Skottsb. -- not accepted
  Artemisia mexicana Willd. ex Spreng. -- not accepted
  Artemisia michauxiana Besser -- accepted -- Michaux's wormwood, Michaux's sagebrush, Michaux's sagewort
  Artemisia minima L. -- not accepted
  Artemisia neomexicana Greene ex Rydb. -- not accepted
  Artemisia nesiotica P.H. Raven -- accepted -- island sagebrush
  Artemisia norvegica Fr. -- accepted -- Norway sagewort
  Artemisia norvegica ssp. norvegica Fr. -- accepted
  Artemisia norvegica ssp. saxatilis (Besser) H.M. Hall & Clem. -- accepted -- boreal sagebrush
  Artemisia norvegica var. comata (Rydb.) S.L. Welsh -- not accepted
  Artemisia norvegica var. norvegica Fr. -- accepted -- Norway sagewort
  Artemisia norvegica var. piceetorum S.L. Welsh & Goodrich -- not accepted
  Artemisia norvegica var. saxatilis (Besser) Jeps. -- not accepted
  Artemisia nova A. Nelson -- accepted -- black sagebrush
  Artemisia nova var. duchesnicola S.L. Welsh & Goodrich -- not accepted
  Artemisia nova var. nova A. Nels. -- not accepted
  Artemisia pabularis (A. Nelson) Rydb. -- not accepted
  Artemisia pacifica Nutt. -- not accepted
  Artemisia packardiae J.W. Grimes & Ertter -- accepted -- Packard's wormwood, Succor Creek sagebrush
  Artemisia palmeri A. Gray -- accepted -- San Diego sagewort
  Artemisia papposa S.F. Blake & Cronquist -- accepted -- Owyhee sage, Owyhee sagebrush
  Artemisia parryi A. Gray -- not accepted -- Parry's wormwood
  Artemisia pattersonii A. Gray -- accepted -- Patterson's wormwood
  Artemisia pedatifida Nutt. -- accepted -- birdfoot sagebrush
  Artemisia pontica L. -- accepted -- Roman wormwood
  Artemisia porteri Cronquist -- accepted -- Porter's wormwood
  Artemisia prescottiana Besser -- not accepted
  Artemisia procera Willd. -- not accepted
  Artemisia purshiana Besser -- not accepted
  Artemisia pycnocephala (Less.) DC. -- accepted -- beach wormwood
  Artemisia pygmaea A. Gray -- accepted -- pygmy sagebrush
  Artemisia redolens A. Gray -- not accepted
  Artemisia richardsoniana Besser -- not accepted
  Artemisia rigida (Nutt.) A. Gray -- accepted -- scabland sagebrush
  Artemisia ripicola Rydb. -- not accepted
  Artemisia rothrockii A. Gray -- accepted -- timberline sagebrush
  Artemisia rupestris L. -- accepted -- rock wormwood
  Artemisia rupestris ssp. rupestris L. -- not accepted -- rock wormwood
  Artemisia sacrorum Ledeb. -- not accepted
  Artemisia scoparia Waldst. & Kit. -- accepted -- redstem wormwood
  Artemisia scopulorum A. Gray -- accepted -- alpine sagebrush, dwarf sagebrush
  Artemisia selengensis Turcz. ex Besser -- not accepted
  Artemisia senjavinensis Besser -- accepted -- arctic wormwood
  Artemisia serrata Nutt. -- accepted -- sawtooth wormwood
  Artemisia sibirica (L.) Maxim. -- not accepted
  Artemisia spiciformis Osterh. -- accepted -- big sagebrush
  Artemisia spiciformis var. longiloba Osterh. -- not accepted
  Artemisia spinescens D.C. Eaton -- not accepted -- bud sagebrush
  Artemisia spithamea Pursh -- not accepted
  Artemisia stelleriana Besser -- accepted -- oldwoman
  Artemisia suksdorfii Piper -- accepted -- coastal wormwood
  Artemisia sulcata Rydb. -- not accepted
  Artemisia tacomensis Rydb. -- not accepted
  Artemisia thuscula Cav. -- accepted
  Artemisia tilesii Ledeb. -- accepted -- Tilesius' wormwood
  Artemisia tilesii auct. non Ledeb. -- not accepted
  Artemisia tilesii ssp. elatior (Torr. & A. Gray) Hultén -- not accepted -- Tilesius' wormwood
  Artemisia tilesii ssp. gormanii (Rydb.) Hultén -- not accepted -- Tilesius' wormwood
  Artemisia tilesii ssp. tilesii Ledeb. -- not accepted -- Tilesius' wormwood
  Artemisia tilesii ssp. unalaschcensis (Besser) Hultén -- not accepted -- Tilesius' wormwood
  Artemisia tilesii var. aleutica (Hultén) S.L. Welsh -- not accepted
  Artemisia tilesii var. elatior Torr. & A. Gray -- not accepted
  Artemisia tilesii var. unalaschcensis Besser -- not accepted
  Artemisia tridentata Nutt. -- accepted -- big sagebrush, big sagebush
  Artemisia tridentata ssp. arbuscula (Nutt.) H.M. Hall & Clem. -- not accepted
  Artemisia tridentata ssp. bolanderi (A. Gray) H.M. Hall & Clem. -- not accepted
  Artemisia tridentata ssp. nova (A. Nelson) H.M. Hall & Clem. -- not accepted
  Artemisia tridentata ssp. parishii (A. Gray) H.M. Hall & Clem. -- accepted -- big sagebrush
  Artemisia tridentata ssp. rothrockii (A. Gray) H.M. Hall & Clem. -- not accepted
  Artemisia tridentata ssp. spiciformis (Osterh.) Kartesz & Gandhi -- not accepted -- big sagebrush, subalpine big sagebrush
  Artemisia tridentata ssp. tridentata Nutt. -- accepted -- basin big sagebrush, big sagebrush
  Artemisia tridentata ssp. trifida (Nutt.) H.M. Hall & Clem. -- not accepted
  Artemisia tridentata ssp. vaseyana (Rydb.) Beetle -- accepted -- big sagebrush, mountain big sagebrush
  Artemisia tridentata ssp. wyomingensis Beetle & Young -- accepted -- big sagebrush, Wyoming big sagebrush
  Artemisia tridentata ssp. xericensis Winward ex R. Rosentreter & R. Kelsey -- not accepted -- big sagebrush
  Artemisia tridentata var. angustifolia A. Gray -- not accepted
  Artemisia tridentata var. bolanderi (A. Gray) McMinn -- not accepted
  Artemisia tridentata var. parishii (A. Gray) Jeps. -- not accepted
  Artemisia tridentata var. pauciflora Winward & Goodrich -- not accepted
  Artemisia tridentata var. rothrockii (A. Gray) McMinn -- not accepted
  Artemisia tridentata var. spiciformis (Osterh.) Dorn -- not accepted
  Artemisia tridentata var. vaseyana (Rydb.) B. Boivin -- not accepted
  Artemisia tridentata var. wyomingensis (Beetle & Young) S.L. Welsh -- not accepted
  Artemisia trifida Nutt. -- not accepted
  Artemisia trifida var. rigida Nutt. -- not accepted
  Artemisia trifurcata Stephan ex Spreng. -- not accepted
  Artemisia tripartita Rydb. -- accepted -- threetip sagebrush
  Artemisia tripartita ssp. rupicola Beetle -- accepted -- Wyoming threetip sagebrush
  Artemisia tripartita ssp. tripartita Rydb. -- accepted -- Idaho threetip sagebrush, threetip sagebrush
  Artemisia tripartita var. rupicola (Beetle) Dorn -- not accepted
  Artemisia tyrellii Rydb. -- not accepted
  Artemisia umbelliformis Lam. -- accepted -- Alps wormwood
  Artemisia unalaskensis Rydb. -- not accepted
  Artemisia unalaskensis var. aleutica Hultén -- not accepted
  Artemisia vaseyana Rydb. -- not accepted
  Artemisia vulgaris L. -- accepted -- common wormwood, hierba de San Juan, mugwort, artemisia
  Artemisia vulgaris ssp. heterophylla (Nutt.) H.M. Hall & Clem. -- not accepted
  Artemisia vulgaris ssp. ludoviciana (Nutt.) H.M. Hall & Clem. -- not accepted
  Artemisia vulgaris ssp. michauxiana (Besser) H. St. John -- not accepted
  Artemisia vulgaris var. coarctata Forselles ex Besser -- not accepted
  Artemisia vulgaris var. douglasiana (Besser) H. St. John -- not accepted
  Artemisia vulgaris var. glabra Ledeb. -- not accepted -- common wormwood
  Artemisia vulgaris var. kamtschatica Besser -- not accepted -- common wormwood
  Artemisia vulgaris var. latiloba Ledeb. -- not accepted -- common wormwood
  Artemisia vulgaris var. ludoviciana (Nutt.) Kuntze -- not accepted
  Artemisia vulgaris var. mexicana (Willd. ex Spreng.) Torr. & A. Gray -- not accepted
  Artemisia vulgaris var. selengensis (Turcz. ex Besser) Maxim. -- not accepted
  Artemisia vulgaris var. vulgaris L. -- accepted -- common wormwood
  Asanthus King & H. Rob. -- accepted -- brickellbush
  Asanthus squamulosus (A. Gray) King & H. Rob. -- accepted -- Mule Mountain brickellbush
  Askellia elegans (Hook.) W.A. Weber -- not accepted
  Askellia nana (Richardson) W.A. Weber -- not accepted
  Askellia nana ssp. ramosa (Babc.) W.A. Weber -- not accepted
  Aster L. -- accepted -- aster
  Aster abatus S.F. Blake -- not accepted
  Aster acadiensis Shinners -- not accepted
  Aster acuminatus Michx. -- not accepted
  Aster acuminatus var. acuminatus Michx. -- not accepted -- whorled wood aster
  Aster acuminatus var. magdalenensis Fernald -- not accepted
  Aster adenolepis S.F. Blake -- not accepted
  Aster adnatus Nutt. -- not accepted -- scaleleaf aster
  Aster adscendens Lindl. -- not accepted
  Aster adsurgens auct. non Greene -- not accepted
  Aster agrostifolius Burgess -- not accepted
  Aster alpigenus (Torr. & A. Gray) A. Gray -- not accepted
  Aster alpigenus ssp. alpigenus (Torr. & Gray) Gray -- not accepted -- tundra aster
  Aster alpigenus ssp. andersonii (A. Gray) Onno -- not accepted
  Aster alpigenus ssp. haydenii (Porter) Cronquist -- not accepted
  Aster alpigenus var. andersonii (A. Gray) Onno ex M. Peck -- not accepted
  Aster alpigenus var. haydenii (Porter) Cronquist -- not accepted
  Aster alpinus L. -- accepted -- alpine aster
  Aster alpinus ssp. vierhapperi Onno -- accepted -- Vierhapper's aster
  Aster alpinus var. alpinus L. -- accepted -- alpine aster
  Aster alpinus var. serpentimontanus (Tamamsch.) Ling -- accepted
  Aster alpinus var. vierhapperi (Onno) Cronquist -- not accepted -- Vierhapper's aster
  Aster altaicus Willd. -- not accepted
  Aster amelloides Besser -- not accepted
  Aster amellus L. -- accepted -- Italian aster, Italian starwort
  Aster amellus ssp. ibericus (Steven) V.E. Avet. -- accepted
  Aster amethystinus Nutt. -- not accepted
  Aster amplifolius (Woot. & Standl.) Kittell -- not accepted
  Aster andersonii (A. Gray) A. Gray -- not accepted
  Aster anomalus Engelm. ex Torr. & A. Gray -- not accepted -- manyray aster
  Aster anticostensis Fernald -- not accepted -- aster d'Anticosti
  Aster apricus (A. Gray) Rydb. -- not accepted
  Aster aquifolius (Greene ex Woot. & Standl.) S.F. Blake -- not accepted
  Aster arenosus (A. Heller) S.F. Blake -- not accepted
  Aster ascendens Lindl. -- not accepted -- Chile aster
  Aster ascendens var. fremontii Torr. & A. Gray -- not accepted
  Aster ascendens var. parryi D.C. Eaton -- not accepted
  Aster ascendens var. yosemitanus A. Gray -- not accepted
  Aster asperifolius E.S. Burgess -- not accepted
  Aster asteroides (L.) MacMill. -- not accepted
  Aster attenuatus auct. non Lindl. ex Hook. -- not accepted
  Aster attenuatus (Howell) M. Peck non Lindl. ex Hook. -- not accepted
  Aster avitus Alexander -- not accepted -- Alexander's rock aster
  Aster azureus Lindl. -- not accepted
  Aster azureus var. poaceus (E.S. Burgess) Fernald -- not accepted
  Aster batesii Rydb. -- not accepted
  Aster behringensis Gandog. -- not accepted -- Behring aster
  Aster bellidiflorus Willd. -- not accepted
  Aster bernardinus H.M. Hall -- not accepted
  Aster bietii Franch. -- accepted
  Aster bifoliatus (Walter) H.E. Ahles -- not accepted
  Aster bigelovii A. Gray -- not accepted
  Aster blakei (Porter) House -- not accepted
  Aster blepharophyllus A. Gray -- not accepted
  Aster bloomeri A. Gray -- not accepted
  Aster boltoniae Greene -- not accepted
  Aster borealis (Torr. & A. Gray) Prov. -- not accepted -- rush aster
  Aster boykinii E.S. Burgess -- not accepted
  Aster bracei Britton ex Small -- not accepted -- Brace's aster
  Aster brachyactis S.F. Blake -- not accepted
  Aster brachytrichus Franch. -- accepted
  Aster bracteolatus auct. non Nutt. -- not accepted -- bract aster
  Aster breweri (A. Gray) Semple -- not accepted
  Aster brickellioides Greene -- not accepted
  Aster brickellioides var. brickellioides Greene -- not accepted -- brickellbush aster
  Aster brickellioides var. glabratus Greene -- not accepted
  Aster caerulescens DC. -- not accepted
  Aster calderi Boivin -- not accepted
  Aster campestris Nutt. -- not accepted -- meadow aster
  Aster campestris var. bloomeri (A. Gray) A. Gray -- not accepted -- Bloomer's aster
  Aster campestris var. campestris Nutt. -- not accepted -- western meadow aster
  Aster camptosorus Small -- not accepted
  Aster canescens Pursh -- not accepted
  Aster canescens var. aristatus Eastw. -- not accepted
  Aster canescens var. latifolius (A. Gray) A. Gray -- not accepted
  Aster canescens var. viscosus (Nutt.) A. Gray -- not accepted
  Aster carmesinus E.S. Burgess -- not accepted
  Aster carolinianus Walter -- not accepted
  Aster castaneus E.S. Burgess -- not accepted
  Aster caucasicus Willd. -- accepted
  Aster chapmanii Torr. & A. Gray -- not accepted -- savannah aster
  Aster chasei G.N. Jones -- not accepted
  Aster chilensis Nees -- not accepted -- creeping aster
  Aster chilensis ssp. adscendens (Lindl.) Cronquist -- not accepted
  Aster chilensis ssp. hallii (A. Gray) Cronquist -- not accepted
  Aster chilensis var. chilensis Nees -- not accepted -- creeping aster
  Aster chilensis var. invenustus (Greene) Jeps. -- not accepted -- Pacific aster
  Aster chilensis var. lentus (Greene) Jeps. -- not accepted
  Aster chilensis var. medius Jeps. -- not accepted -- Pacific aster
  Aster chilensis var. sonomensis (Greene) Jeps. -- not accepted
  Aster chinensis L. -- not accepted
  Aster chlorolepis Burgess -- not accepted -- mountain aster
  Aster cichoriaceus (Greene) S.F. Blake -- not accepted
  Aster ciliolatus Lindl. -- not accepted -- Lindley's aster
  Aster ciliolatus var. ciliolatus Lindl. -- not accepted -- Lindley's aster
  Aster ciliolatus var. comatus (Fernald) A.G. Jones -- not accepted -- Lindley's aster
  Aster ciliolatus var. maccallae (Rydb.) A.G. Jones -- not accepted -- MacCall's aster
  Aster ciliolatus var. wilsonii (Rydb.) A.G. Jones -- not accepted -- Wilson's aster
  Aster claviger E.S. Burgess -- not accepted
  Aster claytonii E.S. Burgess -- not accepted
  Aster coerulescens DC. -- not accepted
  Aster cognatus H.M. Hall -- not accepted
  Aster coloradoensis A. Gray -- not accepted
  Aster columbianus Piper -- not accepted
  Aster commixtus auct. non (Nees) Kuntze -- not accepted
  Aster commixtus (Nees) Kuntze -- not accepted
  Aster commutatus (Torr. & A. Gray) A. Gray -- not accepted
  Aster commutatus var. crassulus (Rydb.) S.F. Blake -- not accepted
  Aster commutatus var. polycephalus S.F. Blake, non Aster polycephalus Rydb. -- not accepted
  Aster concinnus Willd. -- not accepted
  Aster concolor L. -- not accepted -- eastern silver aster
  Aster concolor var. simulatus (Small) R.W. Long -- not accepted
  Aster conduplicatus Burgess -- not accepted
  Aster conspicuus Lindl. -- not accepted -- showy aster
  Aster continuus Small -- not accepted
  Aster cordalenus L.F. Hend. -- not accepted -- aster
  Aster cordifolius L. -- not accepted -- common blue wood aster
  Aster cordifolius ssp. laevigatus (Porter) A.G. Jones -- not accepted
  Aster cordifolius ssp. sagittifolius (Wedem. ex Willd.) A.G. Jones -- not accepted
  Aster cordifolius var. cordifolius L. -- not accepted -- common blue wood aster
  Aster cordifolius var. furbishiae Fernald -- not accepted -- Furbish's wood aster
  Aster cordifolius var. incisus Britton -- not accepted
  Aster cordifolius var. laevigatus Porter -- not accepted -- common blue wood aster
  Aster cordifolius var. lanceolatus Porter -- not accepted -- common blue wood aster
  Aster cordifolius var. moratus (Shinners) Shinners -- not accepted
  Aster cordifolius var. polycephalus Porter -- not accepted -- manyheaded wood aster
  Aster cordifolius var. racemiflorus Fernald -- not accepted -- raceme wood aster
  Aster cordifolius var. sagittifolius (Wedem. ex Willd.) A.G. Jones -- not accepted -- swordleaf wood aster
  Aster cordineri A. Nelson -- not accepted
  Aster coridifolius Michx. -- not accepted
  Aster corrigiatus E.S. Burgess -- not accepted
  Aster covillei (Greene) S.F. Blake ex M. Peck -- not accepted
  Aster crassulus Rydb. -- not accepted
  Aster crenifolius (Fernald) Cronquist -- not accepted
  Aster crenifolius var. arcuans (Fernald) Cronquist -- not accepted
  Aster curtisii Torr. & A. Gray -- not accepted
  Aster curtus Cronquist -- not accepted
  Aster curvescens Burgess -- not accepted
  Aster cusickii A. Gray -- not accepted -- Cusick's aster
  Aster cusickii var. lyallii A. Gray -- not accepted
  Aster decemflora Kuntze -- not accepted
  Aster defoliatus Parish -- not accepted -- San Bernardino aster
  Aster delectabilis H.M. Hall -- not accepted
  Aster depauperatus Fernald -- not accepted -- serpentine aster
  Aster depauperatus var. parviceps (Burgess) Fernald -- not accepted
  Aster deserticola J.F. Macbr. -- not accepted
  Aster diabolicus Piper -- not accepted
  Aster diffusus var. thyrsoides A. Gray -- not accepted
  Aster diplostephioides (DC.) C.B. Clarke -- accepted
  Aster discoideus Elliott -- not accepted
  Aster divaricatus (Nutt.) Torr. & A. Gray non L. -- not accepted -- white wood aster, serpentine aster, aster ŕ rameaux étalés
  Aster divaricatus L. -- not accepted
  Aster divaricatus var. chlorolepis (Burgess) H.E. Ahles -- not accepted
  Aster divaricatus var. sandwicensis A. Gray -- not accepted
  Aster diversifolius Michx. -- not accepted
  Aster douglasii Lindl. -- not accepted
  Aster dracunculoides Lam. -- not accepted
  Aster drummondii Lindl. -- not accepted -- Drummond's aster
  Aster drummondii ssp. parviceps (Shinners) A.G. Jones -- not accepted
  Aster drummondii ssp. texanus (E.S. Burgess) A.G. Jones -- not accepted
  Aster drummondii var. drummondii Lindl. -- not accepted -- Drummond's aster
  Aster drummondii var. parviceps (Shinners) A.G. Jones -- not accepted -- Drummond's aster
  Aster drummondii var. texanus (E.S. Burgess) A.G. Jones -- not accepted -- Texas aster
  Aster dumosus L. -- not accepted -- rice button aster
  Aster dumosus var. coridifolius (Michx.) Torr. & A. Gray -- not accepted
  Aster dumosus var. dodgei Fernald -- not accepted -- Dodge's aster
  Aster dumosus var. dumosus L. -- not accepted -- rice button aster
  Aster dumosus var. gracilentus Torr. & A. Gray -- not accepted
  Aster dumosus var. gracilipes Wiegand -- not accepted -- rice button aster
  Aster dumosus var. pergracilis Wiegand -- not accepted -- rice button aster
  Aster dumosus var. strictior Torr. & A. Gray -- not accepted -- rice button aster
  Aster dumosus var. subulifolius Torr. & A. Gray -- not accepted -- rice button aster
  Aster eatonii (A. Gray) Howell -- not accepted -- Eaton's aster
  Aster elatus (Greene) Cronquist -- not accepted
  Aster elegans (Nutt.) Torr. & A. Gray non Willd. -- not accepted
  Aster elegans var. engelmannii D.C. Eaton -- not accepted
  Aster elegantulus A.E. Porsild -- not accepted
  Aster eliasii A. Nelson -- not accepted
  Aster elliottii Torr. & A. Gray -- not accepted
  Aster elmeri Greene -- not accepted
  Aster elodes Torr. & A. Gray -- not accepted
  Aster eminens Willd. -- not accepted
  Aster engelmannii (D.C. Eaton) A. Gray -- not accepted
  Aster engelmannii var. glaucescens A. Gray -- not accepted
  Aster engelmannii var. ledophyllus A. Gray -- not accepted
  Aster engelmannii var. paucicapitatus B.L. Rob. -- not accepted
  Aster ericaefolius Rothr. -- not accepted
  Aster ericoides L. -- not accepted -- heath aster, white aster, white heath aster
  Aster ericoides ssp. pansus (S.F. Blake) A.G. Jones -- not accepted
  Aster ericoides var. commutatus (Torr. & A. Gray) B. Boivin -- not accepted
  Aster ericoides var. ericoides L. -- not accepted -- heath aster
  Aster ericoides var. pansus (S.F. Blake) B. Boivin -- not accepted -- manyflowered aster
  Aster ericoides var. parviceps E.S. Burgess -- not accepted
  Aster ericoides var. platyphyllus Torr. & A. Gray -- not accepted
  Aster ericoides var. pringlei A. Gray -- not accepted
  Aster ericoides var. prostratus (Kuntze) S.F. Blake -- not accepted -- prostrate heath aster
  Aster ericoides var. pusillus A. Gray -- not accepted
  Aster ericoides var. stricticaulis (Torr. & A. Gray) F.C. Gates -- not accepted -- white heath aster
  Aster ericoides var. strictus Porter -- not accepted
  Aster ericoides var. villosus (Michx.) Torr. & A. Gray -- not accepted
  Aster eryngiifolius Torr. & A. Gray -- not accepted -- thistleleaf aster
  Aster eulae Shinners -- not accepted -- aster
  Aster excavatus E.S. Burgess -- not accepted
  Aster exiguus Rydb. -- not accepted
  Aster exilis Elliot -- not accepted -- slender aster
  Aster exilis var. australis A. Gray -- not accepted
  Aster exscapus Richardson -- not accepted
  Aster falcatus Lindl. -- not accepted -- cluster aster
  Aster falcatus ssp. commutatus (Torr. & A. Gray) A.G. Jones -- not accepted
  Aster falcatus var. commutatus (Torr. & A. Gray) A.G. Jones -- not accepted -- cluster aster
  Aster falcatus var. crassulus (Rydb.) Cronquist -- not accepted -- rough white prairie aster
  Aster falcatus var. falcatus Lindl. -- not accepted -- cluster aster
  Aster falcidens Burgess -- not accepted
  Aster farreri W.W. Sm. & Jeffrey -- accepted
  Aster faxonii Porter -- not accepted
  Aster fendleri A. Gray -- not accepted -- Fendler's aster
  Aster filaginifolius Hook. & Arn. -- not accepted
  Aster finkii Rydb. -- not accepted
  Aster finkii var. moratus Shinners -- not accepted
  Aster firmus Nees -- not accepted
  Aster flaccidus Bunge -- accepted
  Aster flaccidus var. flaccidus Bunge -- accepted
  Aster flexilis E.S. Burgess -- not accepted
  Aster foliaceus Lindl. ex DC. -- not accepted
  Aster foliaceus var. apricus A. Gray -- not accepted -- leafybract aster
  Aster foliaceus var. arcuans Fernald -- not accepted
  Aster foliaceus var. burkei A. Gray -- not accepted
  Aster foliaceus var. canbyi A. Gray -- not accepted -- Canby's aster
  Aster foliaceus var. cusickii (A. Gray) Cronquist -- not accepted
  Aster foliaceus var. eatonii A. Gray -- not accepted
  Aster foliaceus var. foliaceus Lindl. ex DC. -- not accepted -- alpine leafybract aster
  Aster foliaceus var. frondeus A. Gray -- not accepted
  Aster foliaceus var. lyallii (A. Gray) Cronquist -- not accepted
  Aster foliaceus var. parryi (D.C. Eaton) A. Gray -- not accepted -- Parry's aster
  Aster foliaceus var. subgeminatus Fernald -- not accepted
  Aster foliaceus var. sublinearis D.C. Eaton & Grisc. -- not accepted
  Aster foliaceus var. subpetiolatus Fernald -- not accepted
  Aster fontinalis Alexander -- not accepted -- Florida water aster
  Aster forwoodii S. Watson -- not accepted
  Aster fragilis auct. non Willd. -- not accepted -- fragilestem aster, aster fragile
  Aster fragilis var. brachypholis (Small) A.G. Jones -- not accepted -- fragilestem aster
  Aster fragilis var. fragilis Willd. -- not accepted -- fairy aster
  Aster fragilis var. subdumosus (Wiegand) A.G. Jones -- not accepted -- fragilestem aster
  Aster franklinianus Rydb. -- not accepted
  Aster fremontii (Torr. & A. Gray) A. Gray -- not accepted
  Aster fremontii var. parishii A. Gray -- not accepted
  Aster frondeus (A. Gray) Greene -- not accepted
  Aster frondosus (Nutt.) Torr. & A. Gray -- not accepted
  Aster fruticosus L. -- not accepted
  Aster furcatus Burgess -- not accepted -- forked aster
  Aster garibaldii Brugger -- not accepted
  Aster gaspensis Victorin -- not accepted
  Aster gattingeri Alexander non Kuntze -- not accepted
  Aster georgianus Alexander -- not accepted -- Georgia aster
  Aster geyeri (A. Gray) Howell -- not accepted
  Aster glabriuscula (Nutt.) Torr. & A. Gray -- not accepted
  Aster glabriuscula var. parryi (A. Gray) Onno -- not accepted
  Aster glacialis Nutt. -- not accepted
  Aster glaucescens (A. Gray) S.F. Blake -- not accepted
  Aster glaucodes S.F. Blake -- not accepted -- gray aster
  Aster glaucodes ssp. pulcher S.F. Blake -- not accepted
  Aster glaucodes var. formosus (Greene) Kittell -- not accepted -- gray aster
  Aster glaucodes var. glaucodes Blake -- not accepted -- gray aster
  Aster glaucodes var. pulcher (S.F. Blake) Kearney & Peebles ex S.L. Welsh -- not accepted
  Aster glaucus Torr. & A. Gray non Nees -- not accepted
  Aster glaucus var. wasatchensis M.E. Jones -- not accepted
  Aster glehnii F. Schmidt -- accepted
  Aster glomeratus (Bernh. ex Nees) Burgess -- not accepted
  Aster glossophyllus Piper -- not accepted
  Aster goodingii Onno -- not accepted
  Aster gormanii (Piper) S.F. Blake -- not accepted
  Aster gracilescens E.S. Burgess -- not accepted
  Aster gracilipes (Wiegand) Alexander -- not accepted
  Aster gracilis Nutt. -- not accepted -- slender aster
  Aster grandiflorus L. -- not accepted -- largeflower aster
  Aster gravesii Burgess -- not accepted
  Aster grayi Suksd. -- not accepted
  Aster greatae Parish -- not accepted -- Greata's aster
  Aster gymnocephalus auct. non (DC.) A. Gray -- not accepted
  Aster hallii A. Gray -- not accepted -- Hall's aster
  Aster haydenii Porter -- not accepted
  Aster hemisphericus Alexander -- not accepted
  Aster hendersonii Fernald -- not accepted -- Lyall aster
  Aster herveyi A. Gray -- not accepted
  Aster hesperius A. Gray -- not accepted
  Aster hesperius var. laetevirens (Greene) Cronquist -- not accepted
  Aster hesperius var. wootonii Greene -- not accepted
  Aster himalaicus C.B. Clarke -- accepted
  Aster hirsuticaulis Lindl. ex DC. -- not accepted
  Aster hirtellus Lindl. -- not accepted
  Aster hirtifolius S.F. Blake -- not accepted
  Aster horizontalis Desf. -- not accepted
  Aster horridus (Woot. & Standl.) S.F. Blake -- not accepted
  Aster humilis Willd. -- not accepted
  Aster hybridus var. luteus hort. -- not accepted
  Aster hydrophilus Greene ex Woot. & Standl. -- not accepted
  Aster ianthinus E.S. Burgess -- not accepted
  Aster ibericus Steven -- not accepted
  Aster inconspicuus Less. -- not accepted
  Aster infirmus Michx. -- not accepted
  Aster inornatus Greene -- not accepted
  Aster integrifolius Nutt. -- not accepted -- thickstem aster
  Aster interior Wiegand -- not accepted
  Aster intricatus (A. Gray) S.F. Blake -- not accepted
  Aster invenustus Greene -- not accepted
  Aster jessicae Piper -- not accepted -- Jessica's aster
  Aster johannensis Fernald -- not accepted
  Aster johannensis var. villicaulis (A. Gray) Fernald -- not accepted
  Aster jonesiae Lamboy -- not accepted -- Jones' aster
  Aster junceus Aiton -- not accepted
  Aster junceus auct. non Aiton -- not accepted
  Aster junciformis Rydb. -- not accepted
  Aster juniperinus Burgess -- not accepted
  Aster kentuckiensis Britton -- not accepted
  Aster kingii D.C. Eaton -- not accepted
  Aster kingii var. barnebyana (S.L. Welsh & Goodrich) S.L. Welsh -- not accepted
  Aster kingii var. kingii D.C. Eat. -- not accepted -- King's aster
  Aster kumleinii Fr. ex A. Gray -- not accepted
  Aster laetevirens Greene -- not accepted
  Aster laevis L. -- not accepted -- smooth aster
  Aster laevis var. concinnus (Willd.) House -- not accepted -- smooth aster
  Aster laevis var. falcatus Farw. -- not accepted
  Aster laevis var. geyeri A. Gray -- not accepted -- Geyer's smooth aster
  Aster laevis var. guadalupensis A.G. Jones -- not accepted
  Aster laevis var. laevis L. -- not accepted -- smooth blue aster
  Aster laevis var. purpuratus (Nees) A.G. Jones -- not accepted -- smooth aster
  Aster lamarckianus Nees -- not accepted
  Aster lanceolatus Willd. -- not accepted -- white panicle aster
  Aster lanceolatus ssp. hesperius (A. Gray) Semple & Chmiel. -- not accepted -- Siskiyou aster
  Aster lanceolatus ssp. interior (Wiegand) A.G. Jones -- not accepted
  Aster lanceolatus ssp. lanceolatus Willd. -- not accepted -- white panicle aster
  Aster lanceolatus ssp. lanceolatus var. hirsuticaulis Semple & Chmiel. -- not accepted
  Aster lanceolatus ssp. lanceolatus var. interior (Wieg.) Semple & Chmiel. -- not accepted
  Aster lanceolatus ssp. lanceolatus var. lanceolatus Willd. -- not accepted
  Aster lanceolatus ssp. simplex (Willd.) A.G. Jones -- not accepted
  Aster lanceolatus var. hirsuticaulis Semple & Chmiel. -- not accepted
  Aster lanceolatus var. interior (Wiegand) A.G. Jones -- not accepted
  Aster lanceolatus var. interior (Wiegand) Semple & Chmiel. -- not accepted
  Aster lanceolatus var. latifolius Semple & Chmiel. -- not accepted -- white panicle aster
  Aster lanceolatus var. simplex (Willd.) A.G. Jones -- not accepted
  Aster lateriflorus (L.) Britton -- not accepted -- calico aster
  Aster lateriflorus var. angustifolius Wiegand -- not accepted -- calico aster
  Aster lateriflorus var. flagellaris Shinners -- not accepted -- calico aster
  Aster lateriflorus var. hirsuticaulis (Lindl. ex DC.) Porter -- not accepted -- calico aster
  Aster lateriflorus var. horizontalis (Desf.) Farw. -- not accepted -- calico aster
  Aster lateriflorus var. indutus Shinners -- not accepted -- farewell summer
  Aster lateriflorus var. lateriflorus (L.) Britt. -- not accepted -- farewell summer
  Aster lateriflorus var. pendulus (Aiton) Burgess -- not accepted
  Aster lateriflorus var. spatelliformis (Burgess) A.G. Jones -- not accepted -- farewell summer
  Aster lateriflorus var. tenuipes Wiegand -- not accepted
  Aster lateriflorus var. thyrsoides (A. Gray) Sheldon -- not accepted
  Aster latissimifolius var. serotinus Kuntze -- not accepted
  Aster laurentianus Fernald -- not accepted -- rayless alkali aster, aster du Saint-Laurent
  Aster laurentianus var. contiguus Fernald -- not accepted
  Aster laurentianus var. laurentianus Fernald -- not accepted
  Aster laurentianus var. magdalenensis Fernald -- not accepted
  Aster laxifolius var. borealis Torr. & A. Gray -- not accepted
  Aster laxus Willd. -- not accepted
  Aster ledophyllus (A. Gray) A. Gray -- not accepted -- Cascade aster
  Aster ledophyllus var. covillei (Greene) Cronquist -- not accepted
  Aster ledophyllus var. ledophyllus (Gray) Gray -- not accepted -- Cascade aster
  Aster leiodes S.F. Blake -- not accepted
  Aster lemmonii A. Gray -- not accepted
  Aster lentus Greene -- not accepted -- Suisun Marsh aster
  Aster leucanthemifolius Greene -- not accepted
  Aster leucelene S.F. Blake -- not accepted
  Aster linariifolius L. -- not accepted -- flaxleaf aster, aster ŕ feuilles de linaire
  Aster linariifolius var. linariifolius L. -- not accepted -- flaxleaf aster
  Aster linariifolius var. victorinii Fernald -- not accepted
  Aster lindleyanus Torr. & A. Gray -- not accepted
  Aster linearis (Greene) Cory -- not accepted
  Aster linguiformis E.S. Burgess -- not accepted
  Aster linosyris (L.) Bernh. -- accepted -- goldilocks
  Aster longifolius sensu Semple & Heard non Lam. -- not accepted
  Aster longifolius Lam. -- not accepted -- longleaf aster
  Aster longifolius var. villicaulis A. Gray -- not accepted
  Aster longulus Sheldon -- not accepted
  Aster loriformis E.S. Burgess -- not accepted
  Aster lowrieanus Porter -- not accepted
  Aster lowrieanus var. incisus (Britton) Porter -- not accepted
  Aster lowrieanus var. lanceolatus Porter -- not accepted
  Aster lucidulus (A. Gray) Wiegand -- not accepted
  Aster lutescens (Lindl. ex DC.) Torr. & A. Gray -- not accepted
  Aster maackii Regel -- accepted
  Aster maccallae Rydb. -- not accepted
  Aster macounii Rydb. -- not accepted
  Aster macrophyllus L. -- not accepted -- bigleaf aster
  Aster macrophyllus var. apricensis E.S. Burgess -- not accepted -- bigleaf aster
  Aster macrophyllus var. excelsior E.S. Burgess -- not accepted -- bigleaf aster
  Aster macrophyllus var. ianthinus (E.S. Burgess) Fernald -- not accepted -- bigleaf aster
  Aster macrophyllus var. macrophyllus L. -- not accepted -- bigleaf aster
  Aster macrophyllus var. pinguifolius E.S. Burgess -- not accepted -- bigleaf aster
  Aster macrophyllus var. sejunctus E.S. Burgess -- not accepted -- bigleaf aster
  Aster macrophyllus var. velutinus E.S. Burgess -- not accepted -- bigleaf aster
  Aster major (Hook.) Porter -- not accepted
  Aster mearnsii Rydb. -- not accepted
  Aster meritus A. Nelson -- not accepted
  Aster minor Kuntze -- not accepted
  Aster mirabilis Torr. & A. Gray -- not accepted -- bouquet aster
  Aster missouriensis Britton non Kuntze -- not accepted
  Aster missouriensis var. thyrsoides (A. Gray) Wiegand -- not accepted
  Aster modestus Lindl. -- not accepted -- great northern aster
  Aster mohavensis Coville non Kuntze -- not accepted
  Aster mohrii E.S. Burgess -- not accepted
  Aster mollis Rydb. -- not accepted -- soft aster
  Aster mongolicus Franch. -- not accepted
  Aster multiflorus Aiton -- not accepted
  Aster multiflorus var. commutatus Torr. & A. Gray -- not accepted
  Aster multiflorus var. exiguus Fernald -- not accepted
  Aster multiflorus var. pansus S.F. Blake -- not accepted
  Aster multiflorus var. prostratus Kuntze -- not accepted
  Aster multiflorus var. stricticaulis Torr. & A. Gray -- not accepted
  Aster multiformis E.S. Burgess -- not accepted
  Aster nahanniensis Cody -- not accepted
  Aster nebraskensis Britton -- not accepted
  Aster nemoralis Aiton -- not accepted
  Aster neomexicanus Woot. & Standl. -- not accepted
  Aster nobilis Burgess -- not accepted
  Aster novae-angliae L. -- not accepted -- New England aster
  Aster novi-belgii L. -- not accepted -- New Belgium aster
  Aster novi-belgii ssp. johannensis (Fernald) A.G. Jones -- not accepted
  Aster novi-belgii ssp. tardiflorus (L.) A.G. Jones -- not accepted
  Aster novi-belgii var. crenifolius (Fernald) Labrecque & Brouillet -- not accepted
  Aster novi-belgii var. elodes (Torr. & A. Gray) A. Gray -- not accepted -- New Belgium aster
  Aster novi-belgii var. johannensis (Fernald) A.G. Jones -- not accepted -- Johann's aster
  Aster novi-belgii var. litoreus A. Gray -- not accepted -- New Belgium aster
  Aster novi-belgii var. novi-belgii L. -- not accepted -- New Belgium aster
  Aster novi-belgii var. rosaceus Rouss. -- not accepted
  Aster novi-belgii var. tardiflorus (L.) A.G. Jones -- not accepted -- leafybract aster
  Aster novi-belgii var. villicaulis (A. Gray) Boivin -- not accepted -- New Belgium aster
  Aster oblongifolius Nutt. -- not accepted -- aromatic aster
  Aster oblongifolius var. angustatus Shinners -- not accepted
  Aster oblongifolius var. orientis Shinners -- not accepted
  Aster oblongifolius var. rigidulus A. Gray -- not accepted
  Aster occidentalis (Nutt.) Torr. & A. Gray -- not accepted -- western aster
  Aster occidentalis var. delectabilis (H.M. Hall) Ferris -- not accepted -- delectable aster
  Aster occidentalis var. fremontii (Torr. & A. Gray) A.G. Jones -- not accepted -- Fremont's aster
  Aster occidentalis var. intermedius A. Gray -- not accepted -- intermediate aster
  Aster occidentalis var. occidentalis (Nutt.) Torr. & Gray -- not accepted -- western aster
  Aster occidentalis var. parishii (A. Gray) Ferris -- not accepted -- Parish's aster
  Aster occidentalis var. yosemitanus (A. Gray) Cronquist -- not accepted -- Yosemite aster
  Aster ohioensis (Riddell) Kuntze -- not accepted
  Aster ontarionis Wiegand -- not accepted -- Ontario aster
  Aster ontarionis var. glabratus Semple -- not accepted
  Aster oolentangiensis Riddell -- not accepted -- skyblue aster
  Aster oolentangiensis var. laevicaulis (Fernald) A.G. Jones -- not accepted -- skyblue aster
  Aster oolentangiensis var. oolentangiensis Riddell -- not accepted -- skyblue aster
  Aster oolentangiensis var. poaceus (Burgess) A.G. Jones -- not accepted -- skyblue aster
  Aster orcuttii Vasey & Rose -- not accepted
  Aster oregonensis (Nutt.) Cronquist -- not accepted
  Aster oregonensis ssp. californicus (Durand) D.D. Keck -- not accepted
  Aster oregonensis ssp. oregonensis (Nutt.) Cronq. -- not accepted -- Oregon aster
  Aster oregonum (Nutt.) Torr. & A. Gray -- not accepted
  Aster oregonus auct. non (Nutt.) Torr. & A. Gray -- not accepted
  Aster oreophilus Franch. -- accepted
  Aster osterhoutii Rydb. -- not accepted
  Aster palmeri A. Gray non Ericameria palmeri (A. Gray) H.M. Hall -- not accepted
  Aster paludicola Piper -- not accepted
  Aster paludicola var. paludicola Piper -- not accepted
  Aster paludosus Aiton -- not accepted -- southern swamp aster
  Aster paludosus ssp. hemisphericus (Alexander) Cronquist -- not accepted -- southern swamp aster
  Aster paludosus ssp. paludosus Aiton -- not accepted -- southern swamp aster
  Aster paniculatus Lam., non Mill. -- not accepted
  Aster paniculatus var. simplex (Willd.) Burgess -- not accepted
  Aster pansus (S.F. Blake) Cronquist -- not accepted
  Aster pantotrichus S.F. Blake -- not accepted
  Aster pantotrichus var. thyrsoides (A. Gray) S.F. Blake -- not accepted
  Aster parryi A. Gray -- not accepted
  Aster parviceps (E.S. Burgess) Mack. & Bush -- not accepted -- smallhead aster
  Aster parviflorus A. Gray non Nees -- not accepted
  Aster parvulus S.F. Blake -- not accepted
  Aster patens Aiton -- not accepted -- late purple aster
  Aster patens var. floridanus R.W. Long -- not accepted
  Aster patens var. georgianus (Alexander) Cronquist -- not accepted
  Aster patens var. gracilis Hook. -- not accepted -- late purple aster
  Aster patens var. patens Aiton -- not accepted -- late purple aster
  Aster patens var. patentissimus (Lindl. ex DC.) Torr. & A. Gray -- not accepted -- late purple aster
  Aster patens var. phlogifolius (Muhl. ex Willd.) Nees -- not accepted
  Aster patentissimus Lindl. ex DC. -- not accepted
  Aster paternus Cronquist -- not accepted
  Aster pattersonii A. Gray -- not accepted
  Aster paucicapitatus (B.L. Rob.) B.L. Rob. -- not accepted
  Aster pauciflorus Nutt. -- not accepted
  Aster pedionomus Alexander -- not accepted
  Aster peirsonii Sharsm. -- not accepted
  Aster pendulus Aiton -- not accepted
  Aster perelegans A. Nelson & J.F. Macbr. -- not accepted -- elegant aster
  Aster phlogifolius Muhl. ex Willd. -- not accepted
  Aster phyllodes Rydb. -- not accepted
  Aster phyllolepis Torr. & A. Gray -- not accepted
  Aster pickettianus Suksd. -- not accepted
  Aster pilosus Willd. -- not accepted -- white oldfield aster, white heath aster
  Aster pilosus ssp. parviceps (E.S. Burgess) A.G. Jones -- not accepted
  Aster pilosus var. demotus S.F. Blake -- not accepted -- white oldfield aster
  Aster pilosus var. pilosus Willd. -- not accepted -- white oldfield aster
  Aster pilosus var. platyphyllus (Torr. & A. Gray) S.F. Blake -- not accepted
  Aster pilosus var. priceae (Britton) Cronquist -- not accepted -- white oldfield aster
  Aster pilosus var. pringlei (A. Gray) S.F. Blake -- not accepted -- Pringle's aster
  Aster pilosus var. pusillus (A. Gray) A.G. Jones -- not accepted
  Aster pinifolius Alexander non Nees -- not accepted
  Aster pinnatifidus (Hook.) Kuntze -- not accepted
  Aster plumarius Burgess -- not accepted
  Aster plumosus Small -- not accepted
  Aster poaceus E.S. Burgess -- not accepted
  Aster polycephalus Rydb. -- not accepted
  Aster polyphyllus Willd. non Moench -- not accepted
  Aster porteri A. Gray -- not accepted -- Porter's aster
  Aster potosinus A. Gray -- not accepted -- Santa Rita Mountain aster
  Aster praealtus Poir. -- not accepted -- willowleaf aster
  Aster praealtus var. angustior Wiegand -- not accepted -- willowleaf aster
  Aster praealtus var. coerulescens (DC.) A.G. Jones -- not accepted -- willowleaf aster
  Aster praealtus var. imbricatior Wiegand -- not accepted -- willowleaf aster
  Aster praealtus var. nebraskensis (Britton) Wiegand -- not accepted -- Nebraska aster
  Aster praealtus var. praealtus Poir. -- not accepted -- willowleaf aster
  Aster praealtus var. subasper (Lindl.) Wiegand -- not accepted -- willowleaf aster
  Aster praealtus var. texicola Wiegand -- not accepted
  Aster pratensis Raf. -- not accepted
  Aster prenanthoides Muhl. ex Willd. -- not accepted -- crookedstem aster
  Aster priceae Britton -- not accepted
  Aster pringlei (A. Gray) Britton -- not accepted
  Aster procumbens Houst. ex Mill. -- not accepted
  Aster proteus E.S. Burgess -- not accepted
  Aster ptarmicoides (Nees) Torr. & A. Gray -- not accepted
  Aster ptarmicoides var. georgianus A. Gray -- not accepted
  Aster ptarmicoides var. lutescens (Lindl. ex DC.) A. Gray -- not accepted
  Aster pubentior Cronquist -- not accepted
  Aster punctatus Waldst. & Kit. -- not accepted
  Aster puniceus L. -- not accepted -- purplestem aster
  Aster puniceus ssp. elliottii (Torr. & A. Gray) A.G. Jones -- not accepted
  Aster puniceus ssp. firmus (Nees) A.G. Jones -- not accepted
  Aster puniceus var. calderi (B. Boivin) Lepage -- not accepted -- Calder's aster
  Aster puniceus var. calvus Shinners -- not accepted
  Aster puniceus var. compactus Fernald -- not accepted
  Aster puniceus var. demissus Lindl. -- not accepted
  Aster puniceus var. elliottii (Torr. & A. Gray) A.G. Jones -- not accepted -- Elliott's aster
  Aster puniceus var. firmus (Nees) Torr. & A. Gray -- not accepted -- purplestem aster
  Aster puniceus var. lucidulus A. Gray -- not accepted
  Aster puniceus var. oligocephalus Fernald -- not accepted
  Aster puniceus var. perlongus Fernald -- not accepted -- purplestem aster
  Aster puniceus var. puniceus L. -- not accepted -- purplestem aster
  Aster puniceus var. scabricaulis (Shinners) A.G. Jones -- not accepted -- purplestem aster
  Aster purpuratus Nees -- not accepted
  Aster pygmaea Lindl. -- not accepted
  Aster pyrenaeus Desf. ex DC. -- accepted
  Aster racemosus Elliot -- not accepted
  Aster radula Aiton -- not accepted -- low rough aster
  Aster radula var. radula Aiton -- not accepted -- low rough aster
  Aster radula var. strictus (Pursh) A. Gray -- not accepted -- low rough aster
  Aster radulinus A. Gray -- not accepted -- roughleaf aster
  Aster ramosissimus auct. non Mill. -- not accepted
  Aster ramulosus Lindl. -- not accepted
  Aster reticulatus Pursh -- not accepted
  Aster retroflexus Lindl. ex DC. -- not accepted -- rigid aster
  Aster richardsonii Spreng. -- not accepted
  Aster riciniatus E.S. Burgess -- not accepted
  Aster riparius Kunth -- not accepted
  Aster robynsianus Rouss. -- not accepted
  Aster rolandii Shinners -- not accepted
  Aster roscidus Burgess -- not accepted
  Aster rotundifolius Thunb. -- not accepted
  Aster rubrotinctus S.F. Blake -- not accepted
  Aster sagittifolius Wedem. ex Willd. -- not accepted
  Aster sagittifolius auct. non Wedem. ex Willd. -- not accepted
  Aster sagittifolius var. drummondii (Lindl.) Shinners -- not accepted
  Aster sagittifolius var. urophyllus (Lindl.) Burgess -- not accepted
  Aster salicifolius Aiton non Lam. -- not accepted
  Aster salicifolius sensu Willd. non Lam. nec Aiton -- not accepted
  Aster sandwicensis (A. Gray) Hieron. -- not accepted
  Aster saundersii Burgess -- not accepted
  Aster saxatilis (Fernald) Blanch. -- not accepted
  Aster saxicastellii J.J.N. Campbell & M. Medley -- not accepted -- rockcastle aster
  Aster scaber Thunb. -- not accepted
  Aster scabricaulis Shinners -- not accepted
  Aster schistosus Steele -- not accepted
  Aster schreberi Nees -- not accepted -- Schreber's aster
  Aster scopulorum A. Gray -- not accepted
  Aster sedifolius L. -- accepted
  Aster sedifolius ssp. dracunculoides (Lam.) Merxm. -- accepted
  Aster sericeus Vent. -- not accepted -- western silver aster
  Aster sericeus var. microphyllus DC. -- not accepted -- western silver aster
  Aster sericeus var. sericeus Vent. -- not accepted -- western silver aster
  Aster sericocarpoides (Small) K. Schum. -- not accepted
  Aster serpentimontanus Tamamsch. -- not accepted
  Aster shastensis (A. Gray) A. Gray -- not accepted
  Aster shastensis var. eradiatus A. Gray -- not accepted
  Aster shastensis var. glossophyllus (Piper) Cronquist -- not accepted
  Aster shastensis var. latifolius Cronquist -- not accepted
  Aster shortii Lindl. -- not accepted -- Short's aster
  Aster sibiricus L. -- not accepted -- Siberian aster
  Aster sibiricus ssp. pygmaeus (Lindl.) A. Löve & D. Löve -- not accepted
  Aster sibiricus ssp. richardsonii (Spreng.) A. Löve & D. Löve -- not accepted
  Aster sibiricus var. giganteus (Hook.) A. Gray -- not accepted -- giant arctic aster
  Aster sibiricus var. meritus (A. Nelson) Raup -- not accepted
  Aster sibiricus var. pygmaeus (Lindl.) W.J. Cody -- not accepted -- pygmy arctic aster
  Aster sibiricus var. sibiricus L. -- not accepted
  Aster simmondsii Small -- not accepted -- Simmonds' aster
  Aster simplex Willd. -- not accepted
  Aster simplex var. estuarinus B. Boivin -- not accepted
  Aster simplex var. interior (Wiegand) Cronquist -- not accepted
  Aster simplex var. ramosissimus (Torr. & A. Gray) Cronquist -- not accepted
  Aster simulatus Small -- not accepted
  Aster siskiyouensis A. Nelson & J.F. Macbr. -- not accepted
  Aster smallii Alexander -- not accepted
  Aster solidagineus Michx. -- not accepted
  Aster sonomensis Greene -- not accepted
  Aster sonorae A. Gray -- not accepted
  Aster spatelliformis Burgess -- not accepted
  Aster spathulatus Lindl. -- not accepted
  Aster spectabilis Aiton -- not accepted -- western showy aster
  Aster spectabilis var. cinerascens S.F. Blake -- not accepted -- western showy aster
  Aster spectabilis var. spectabilis Ait. -- not accepted -- western showy aster
  Aster spectabilis var. suffultus Fernald -- not accepted -- western showy aster
  Aster spinosus Benth. -- not accepted
  Aster spinulosus Chapm. -- not accepted -- Apalachicola aster
  Aster squamatus (Spreng.) Hieron. -- not accepted
  Aster squarrosus sensu Walter non All. -- not accepted
  Aster standleyi Davidson -- not accepted
  Aster steeleorum Shinners -- not accepted
  Aster stenomeres A. Gray -- not accepted
  Aster stilettiformis E.S. Burgess -- not accepted
  Aster stricticaulis (Torr. & A. Gray) Rydb. -- not accepted
  Aster strictus Pursh non Poir. -- not accepted
  Aster subasper Lindl. -- not accepted
  Aster subgeminatus (Fernald) Boivin -- not accepted -- aster
  Aster subgriseus Rydb. -- not accepted
  Aster subintegerrimus (Trautv.) Ostenf. & Resvoll -- not accepted
  Aster subsessilis E.S. Burgess -- not accepted
  Aster subspicatus Nees -- not accepted -- Douglas aster
  Aster subspicatus var. apricus (A. Gray) Boivin -- not accepted
  Aster subspicatus var. grayi (Suksd.) Cronquist -- not accepted -- Gray's aster
  Aster subspicatus var. subspicatus Nees -- not accepted -- leafybract aster
  Aster subulatus Michx. -- not accepted -- annual saltmarsh aster
  Aster subulatus var. australis (A. Gray) Shinners -- not accepted
  Aster subulatus var. cubensis (DC.) Shinners -- not accepted -- annual saltmarsh aster
  Aster subulatus var. elongatus Bosser. ex A.G. Jones & Lowry -- not accepted
  Aster subulatus var. euroauster Fernald & Grisc. -- not accepted -- annual saltmarsh aster
  Aster subulatus var. ligulatus Shinners -- not accepted -- annual saltmarsh aster, slender aster, southern annual saltmarsh aster, panicled aster, saltmarsh aster
  Aster subulatus var. obtusifolius Fernald -- not accepted -- annual saltmarsh aster
  Aster subulatus var. sandwicensis (A. Gray) A.G. Jones -- not accepted -- annual saltmarsh aster
  Aster subulatus var. subulatus Michx. -- not accepted -- annual saltmarsh aster
  Aster sulznerae Small -- not accepted
  Aster surculosus Michx. -- not accepted -- creeping aster
  Aster sylvestris E.S. Burgess -- not accepted
  Aster tagetinus (Greene) S.F. Blake -- not accepted
  Aster tanacetifolius Kunth -- not accepted
  Aster tardiflorus var. vestitus Fernald -- not accepted
  Aster tataricus L. f. -- accepted -- Tatarian aster
  Aster tenebrosus E.S. Burgess -- not accepted
  Aster tenerrimus Less. -- not accepted
  Aster tenuicaulis (C. Mohr) E.S. Burgess -- not accepted
  Aster tenuifolius L. -- not accepted -- saline aster
  Aster tenuifolius var. aphyllus R.W. Long -- not accepted
  Aster tenuifolius var. ramosissimus Torr. & A. Gray -- not accepted
  Aster tephrodes (A. Gray) S.F. Blake -- not accepted
  Aster texanus E.S. Burgess -- not accepted
  Aster texanus var. parviceps Shinners -- not accepted
  Aster thomsonii C.B. Clarke -- accepted
  Aster tibeticus Hook. f. -- not accepted
  Aster tomentellus (Greene) Frye & Rigg non Hook. -- not accepted
  Aster tongolensis Franch. -- accepted
  Aster torreyi Kuntze -- not accepted
  Aster tortifolius Michx. -- not accepted
  Aster tortifolius (Torr. & A. Gray) A. Gray non Michx. -- not accepted
  Aster tradescantii L. -- not accepted
  Aster tradescantii var. saxatilis (Fernald) House -- not accepted
  Aster tradescantii var. thyrsoides (A. Gray) B. Boivin -- not accepted
  Aster triangularis E.S. Burgess -- not accepted
  Aster tripolium L. -- not accepted -- sea aster
  Aster tripolium ssp. pannonicus (Jacq.) Soo -- not accepted
  Aster truellius E.S. Burgess -- not accepted
  Aster turbinellus Lindl. -- not accepted -- smooth violet prairie aster
  Aster tweedyi Rydb. -- not accepted
  Aster uliginosus J.M. Wood & M.S. Evans -- not accepted
  Aster umbellatus Mill. -- not accepted
  Aster umbellatus var. brevisquamis Fernald -- not accepted
  Aster umbellatus var. latifolius A. Gray -- not accepted
  Aster umbellatus var. pubens A. Gray -- not accepted
  Aster unalaschkensis var. major Hook. -- not accepted
  Aster undulatus L. -- not accepted -- waxyleaf aster
  Aster undulatus var. asperulus Alph. Wood -- not accepted -- waxyleaf aster
  Aster undulatus var. diversifolius (Michx.) A. Gray -- not accepted
  Aster undulatus var. loriformis E.S. Burgess -- not accepted -- waxyleaf aster
  Aster undulatus var. triangularis E.S. Burgess -- not accepted
  Aster undulatus var. undulatus L. -- not accepted -- waxyleaf aster
  Aster urophyllus Lindl. ex DC. -- not accepted -- white arrow aster
  Aster vahlii (Gaudich.) Hook. & Arn. -- not accepted
  Aster venustus M.E. Jones -- not accepted
  Aster vernalis Engelm. ex E.S. Burgess -- not accepted
  Aster verutifolius Alexander -- not accepted
  Aster vialis (Bradshaw) S.F. Blake -- not accepted
  Aster villosus Michx. -- not accepted
  Aster vimineus auct. non Lam. -- not accepted
  Aster vimineus Lam. -- not accepted
  Aster vimineus var. saxatilis Fernald -- not accepted
  Aster vimineus var. subdumosus Wiegand -- not accepted
  Aster violaris Burgess -- not accepted
  Aster virgatus Elliott non Moench -- not accepted
  Aster walteri Alexander -- not accepted -- Walter's aster
  Aster wasatchensis (M.E. Jones) S.F. Blake -- not accepted -- Wasatch aster
  Aster watsonii A. Gray -- not accepted
  Aster welshii Cronquist -- not accepted
  Aster wilsonii Rydb. -- not accepted
  Aster woldenii Rydb. -- not accepted
  Aster wootonii (Greene) Greene -- not accepted
  Aster wrightii A. Gray -- not accepted
  Aster X amethystinus Nutt. (pro sp.) -- not accepted -- amethyst aster
  Aster X batesii Rydb. (pro sp.) -- not accepted -- Bates' aster
  Aster X columbianus Piper (pro sp.) -- not accepted -- Columbian aster
  Aster X gravesii Burgess (pro sp.) -- not accepted -- Graves' aster
  Aster X herveyi A. Gray (pro sp.) -- not accepted -- Hervey's aster
  Aster X longulus Sheldon (pro sp.) -- not accepted -- aster
  Aster X salignus Willd. -- not accepted
  Aster X schistosus Steele (pro sp.) -- not accepted -- aster
  Aster X tardiflorus L. (pro sp.) -- not accepted
  Aster X versicolor Willd. (pro sp.) -- not accepted
  Aster X woldenii Rydb. (pro sp.) -- not accepted -- Wolden's aster
  Aster xylorhiza (Nutt.) Torr. & A. Gray -- not accepted
  Aster yosemitanus (A. Gray) Greene -- not accepted
  Aster yukonensis Cronquist -- not accepted -- Yukon aster
  Aster yunnanensis Franch. -- accepted
  Asteraceae -- accepted -- sunflowers, tournesols
  Astranthium Nutt. -- accepted -- western daisy
  Astranthium ciliatum (Raf.) G.L. Nesom -- accepted -- Comanche western-daisy, entireleaf western daisy
  Astranthium integrifolium (Michx.) Nutt. -- accepted -- entireleaf western daisy
  Astranthium integrifolium ssp. ciliatum (Raf.) DeJong -- not accepted -- entireleaf western daisy
  Astranthium integrifolium ssp. integrifolium (Michx.) Nutt. -- accepted -- entireleaf western daisy
  Astranthium integrifolium var. ciliatum (Raf.) Larsen -- not accepted
  Astranthium integrifolium var. robustum Shinners -- not accepted
  Astranthium integrifolium var. triflorum (Raf.) Shinners -- not accepted
  Astranthium robustum (Shinners) DeJong -- accepted -- Texas western daisy
  Atrichoseris A. Gray -- accepted -- atrichoseris
  Atrichoseris platyphylla (A. Gray) A. Gray -- accepted -- parachute plant, parachute-plant, gravel ghost
  Ayapana Spach -- accepted
  Ayapana triplinervis (Vahl) King & H. Rob. -- accepted -- yapana
  Baccharis L. -- accepted -- baccharis
  Baccharis angustifolia Michx. -- accepted -- saltwater false willow
  Baccharis bigelovii A. Gray -- accepted -- Bigelow's false willow, Bigelow baccharis, Bigelow's falsewillow
  Baccharis brachyphylla A. Gray -- accepted -- shortleaf baccharis
  Baccharis concava (Ruiz & Pav.) Pers. -- accepted
  Baccharis dioica Vahl -- accepted -- broombush false willow
  Baccharis douglasii DC. -- accepted -- saltmarsh baccharis
  Baccharis emoryi A. Gray -- not accepted -- Emory's baccharis
  Baccharis glomeruliflora Pers. -- accepted -- silverling
  Baccharis glutinosa Pers. -- not accepted
  Baccharis halimifolia L. -- accepted -- eastern baccharis
  Baccharis halimifolia var. angustior DC. -- not accepted
  Baccharis halimifolia var. halimifolia L. -- not accepted
  Baccharis havardii A. Gray -- accepted -- Havard's false willow, Havard's falsewillow
  Baccharis malibuensis R.M. Beauch. & J. Henrickson -- accepted -- Malibu baccharis
  Baccharis myrsinites (Lam.) Pers. -- accepted -- Santo Domingo false willow
  Baccharis neglecta Britton -- accepted -- Rooseveltweed, Roosevelt-weed
  Baccharis pilularis DC. -- accepted -- coyotebrush
  Baccharis pilularis ssp. consanguinea (DC.) C.B. Wolf -- accepted
  Baccharis pilularis ssp. pilularis DC. -- accepted -- coyotebrush
  Baccharis pilularis var. consanguinea (DC.) Kuntze -- not accepted
  Baccharis plummerae A. Gray -- accepted -- Plummer's baccharis
  Baccharis plummerae ssp. glabrata Hoover -- accepted -- smooth baccharis
  Baccharis plummerae ssp. plummerae A. Gray -- accepted -- Plummer's baccharis
  Baccharis pteronioides DC. -- accepted -- yerba de pasmo, yerba-de-pasmo
  Baccharis salicifolia (Ruiz & Pav.) Pers. -- accepted -- mule's fat, seep willow, seepwillow, seepwillow baccharis, mule-fat
  Baccharis salicina Torr. & A. Gray -- accepted -- Great Plains false willow, Emory's baccharis, Great Plains falsewillow, willow baccharis
  Baccharis sarothroides A. Gray -- accepted -- desertbroom, desert broom, broom baccharis
  Baccharis sergiloides A. Gray -- accepted -- desert baccharis, squaw waterweed baccharis
  Baccharis texana (Torr. & A. Gray) A. Gray -- accepted -- prairie false willow, prairie baccharis, prairie falsewillow
  Baccharis thesioides Kunth -- accepted -- Arizona baccharis, Mogollon baccharis
  Baccharis vanessae R.M. Beauch. -- accepted -- coyote bush, Encinitis false willow, Encinitas baccharis
  Baccharis viminea DC. -- not accepted
  Baccharis wrightii A. Gray -- accepted -- Wright's baccharis
  Baeria bakeri J.T. Howell -- not accepted
  Baeria californica (Hook.) K.L. Chambers -- not accepted
  Baeria chrysostoma Fisch. & C.A. Mey. -- not accepted
  Baeria chrysostoma ssp. gracilis (DC.) Ferris -- not accepted
  Baeria chrysostoma ssp. hirsutula (Greene) Ferris -- not accepted
  Baeria chrysostoma var. gracilis (DC.) H.M. Hall -- not accepted
  Baeria debilis Greene ex A. Gray -- not accepted
  Baeria fremontii (Torr. ex A. Gray) A. Gray -- not accepted
  Baeria fremontii var. conjugens (Greene) Ferris -- not accepted
  Baeria fremontii var. heterochaeta Hoover -- not accepted
  Baeria hirsutula (Greene) Greene -- not accepted
  Baeria leptalea (A. Gray) A. Gray -- not accepted
  Baeria macrantha (A. Gray) A. Gray -- not accepted
  Baeria macrantha var. bakeri (J.T. Howell) D.D. Keck -- not accepted
  Baeria macrantha var. pauciaristata A. Gray -- not accepted
  Baeria macrantha var. thalassophila J.T. Howell -- not accepted
  Baeria maritima A. Gray -- not accepted
  Baeria microglossa (DC.) Greene -- not accepted
  Baeria minor (DC.) Ferris -- not accepted
  Baeria minor ssp. maritima (A. Gray) Ferris -- not accepted
  Baeria platycarpha (A. Gray) A. Gray -- not accepted
  Baeria uliginosa (Nutt.) A. Gray -- not accepted
  Bahia Lag. -- accepted -- bahia
  Bahia absinthifolia Benth. -- accepted -- hairyseed bahia
  Bahia absinthifolia var. absinthifolia Benth. -- not accepted -- hairyseed bahia, hairy-seed false goldfields
  Bahia absinthifolia var. dealbata (A. Gray) A. Gray -- not accepted -- Dealbata's bahia
  Bahia bigelovii A. Gray -- accepted -- Bigelow's bahia
  Bahia biternata A. Gray -- accepted -- slimlobe bahia, slim-lobe false goldfields
  Bahia dissecta (A. Gray) Britton -- not accepted -- ragleaf bahia
  Bahia neomexicana (A. Gray) A. Gray -- not accepted
  Bahia nudicaulis A. Gray -- not accepted
  Bahia nudicaulis var. desertorum (M.E. Jones) Cronquist -- not accepted
  Bahia nudicaulis var. oblongifolia (A. Gray) Cronquist -- not accepted
  Bahia nudicaulis var. ourolepis (S.F. Blake) Cronquist -- not accepted
  Bahia oblongifolia (A. Gray) A. Gray -- not accepted
  Bahia oppositifolia (Nutt.) A. Gray -- not accepted
  Bahia ourolepis S.F. Blake -- not accepted
  Bahia pedata A. Gray -- accepted -- bluntscale bahia, blunt-scale false goldfields
  Bahia schaffneri S. Watson -- accepted -- Schaffner's bahia
  Bahia woodhousei (A. Gray) A. Gray -- not accepted
  Bahiopsis Kellogg -- accepted
  Bahiopsis laciniata (A. Gray) E.E. Schill. & Panero -- accepted -- torhleaf goldeneye
  Bahiopsis parishii (Greene) E.E. Schill. & Panero -- accepted -- Parish's goldeneye
  Bahiopsis reticulata (S. Watson) E.E. Schill. & Panero -- accepted -- netvein goldeneye
  Baileya Harv. & A. Gray ex A. Gray -- accepted -- desert marigold, baileya
  Baileya multiradiata Harv. & A. Gray ex A. Gray -- accepted -- desert marigold, desert baileya
  Baileya multiradiata var. pleniradiata (Harv. & A. Gray ex A. Gray) Coville -- not accepted
  Baileya multiradiata var. thurberi (Rydb.) Kittell -- not accepted
  Baileya pauciradiata Harv. & A. Gray ex A. Gray -- accepted -- laxflower
  Baileya perennis (A. Nelson) Rydb. -- not accepted
  Baileya pleniradiata Harv. & A. Gray ex A. Gray -- accepted -- woolly desert marigold, woolly desert-marigold, desertmarigold baileya
  Balduina Nutt. -- accepted -- honeycombhead
  Balduina angustifolia (Pursh) B.L. Rob. -- accepted -- coastal plain honeycombhead, coastalplain honeycombhead
  Balduina atropurpurea Harper -- accepted -- purpledisk honeycombhead
  Balduina uniflora Nutt. -- accepted -- oneflower honeycombhead
  Balsamita Mill. -- accepted -- balsamita
  Balsamita major Desf. -- not accepted -- costmary, costmary chrysanthemum, mint geranium
  Balsamita major var. tanacetoides (Boiss.) Moldenke -- not accepted
  Balsamorhiza Nutt. -- accepted -- balsamroot
  Balsamorhiza bolanderi A. Gray -- not accepted
  Balsamorhiza bonseri H. St. John -- not accepted
  Balsamorhiza careyana A. Gray -- accepted -- Carey's balsamroot, intermediate balsamroot
  Balsamorhiza careyana var. careyana A. Gray -- not accepted -- Carey's balsamroot
  Balsamorhiza careyana var. intermedia Cronquist -- not accepted -- intermediate balsamroot
  Balsamorhiza deltoidea Nutt. -- accepted -- deltoid balsamroot
  Balsamorhiza hirsuta Nutt. -- not accepted
  Balsamorhiza hirsuta var. lagocephala Sharp -- not accepted
  Balsamorhiza hirsuta var. neglecta Sharp -- not accepted
  Balsamorhiza hispidula Sharp -- accepted -- hairy balsamroot
  Balsamorhiza hookeri (Hook.) Nutt. -- accepted -- Hooker's balsamroot, hairy balsamroot, rabbithead balsamroot, neglected balsamroot
  Balsamorhiza hookeri var. hirsuta (Nutt.) A. Nelson -- not accepted -- hairy balsamroot
  Balsamorhiza hookeri var. hispidula (Sharp) Cronquist -- not accepted -- hairy balsamroot
  Balsamorhiza hookeri var. hookeri (Hook.) Nutt. -- not accepted -- Hooker's balsamroot
  Balsamorhiza hookeri var. idahoensis (Sharp) Cronquist -- not accepted -- Idaho balsamroot
  Balsamorhiza hookeri var. lagocephala (Sharp) Cronquist -- not accepted -- rabbithead balsamroot
  Balsamorhiza hookeri var. lanata Sharp -- not accepted
  Balsamorhiza hookeri var. neglecta (Sharp) Cronquist -- not accepted -- neglected balsamroot
  Balsamorhiza hookeri var. platylepis (Sharp) Cronquist -- not accepted
  Balsamorhiza incana Nutt. -- accepted -- hoary balsamroot
  Balsamorhiza lanata (Sharp) W.A. Weber -- accepted -- lanate balsamroot
  Balsamorhiza macrolepis Sharp -- accepted -- California balsamroot, silvery balsamroot
  Balsamorhiza macrolepis var. macrolepis Sharp -- not accepted -- California balsamroot
  Balsamorhiza macrolepis var. platylepis (Sharp) Ferris -- not accepted -- California balsamroot
  Balsamorhiza macrophylla Nutt. -- accepted -- cutleaf balsamroot, Idaho balsamroot
  Balsamorhiza macrophylla var. idahoensis Sharp -- not accepted
  Balsamorhiza platylepis Sharp -- not accepted
  Balsamorhiza rosea A. Nelson & J.F. Macbr. -- accepted -- rosy balsamroot
  Balsamorhiza sagittata (Pursh) Nutt. -- accepted -- arrowleaf balsamroot
  Balsamorhiza sericea W.A. Weber -- accepted -- silky balsamroot
  Balsamorhiza serrata A. Nelson & J.F. Macbr. -- accepted -- serrate balsamroot, serrated balsamroot
  Balsamorhiza X bonseri H. St. John (pro sp.) -- accepted -- Bonser's balsamroot
  Balsamorhiza X terebinthacea (Hook.) Nutt. (pro sp.) -- accepted -- balsamroot
  Balsamorhiza X tomentosa Rydb. (pro sp.) -- accepted -- tomentose balsamroot
  Baltimora L. -- accepted -- baltimora
  Baltimora recta L. -- accepted -- beautyhead
  Barkleyanthus (Kunth) H. Rob. & Brettell -- accepted -- willow ragwort
  Barkleyanthus salicifolius (Kunth) H. Rob. & Brettell -- accepted -- willow ragwort
  Bartlettia A. Gray -- accepted -- bartlettia
  Bartlettia scaposa A. Gray -- accepted -- Bartlett daisy
  Bartlettina R.M. King & H. Rob. -- accepted -- bartlettina
  Bartlettina sordida (Less.) King & H. Rob. -- not accepted
  Bebbia (Benth.) Greene -- accepted -- sweetbush, bebbia
  Bebbia juncea (Benth.) Greene -- accepted -- sweetbush, sweetbush bebbia
  Bebbia juncea var. aspera (Benth.) Greene -- accepted -- sweetbush, bebbia
  Bebbia juncea var. juncea (Benth.) Greene -- accepted -- sweetbush
  Bellis L. -- accepted -- bellis
  Bellis integrifolia Michx. -- not accepted
  Bellis perennis L. -- accepted -- lawndaisy, English daisy, European daisy, lawn daisy
  Benitoa D.D. Keck -- accepted -- benitoa
  Benitoa occidentalis (H.M. Hall) D.D. Keck -- accepted -- benitoa
  Berkheya Ehrh. -- accepted -- berkheya
  Berkheya heterophylla O. Hoffm. -- accepted -- prickly gousblom
  Berlandiera DC. -- accepted -- greeneyes, berlandiera
  Berlandiera betonicifolia (Hook.) Small -- not accepted
  Berlandiera dealbata (Torr. & A. Gray) Small -- not accepted
  Berlandiera incisa Torr. & A. Gray -- not accepted
  Berlandiera lyrata Benth. -- accepted -- lyreleaf greeneyes, greeneyes
  Berlandiera lyrata var. macrophylla A. Gray -- not accepted
  Berlandiera monocephala (B.L. Turner) Pinkava -- accepted
  Berlandiera pumila (Michx.) Nutt. -- accepted -- soft greeneyes
  Berlandiera pumila var. pumila (Michx.) Nutt. -- not accepted
  Berlandiera pumila var. scabrella G.L. Nesom & B.L. Turner -- not accepted
  Berlandiera subacaulis (Nutt.) Nutt. -- accepted -- Florida greeneyes
  Berlandiera texana DC. -- accepted -- Texas greeneyes
  Berlandiera texana var. betonicifolia (Hook.) Torr. & A. Gray -- not accepted
  Berlandiera tomentosa (Pursh) Nutt. -- not accepted
  Berlandiera tomentosa var. dealbata Torr. & A. Gray -- not accepted
  Berlandiera X betonicifolia (Hook.) Small (pro sp.) -- accepted -- Texas greeneyes, berlandiera
  Berlandiera X humilis Small (pro sp.) -- accepted -- berlandiera
  Berlandiera X macrophylla (A. Gray) M.E. Jones -- accepted
  Berthelotia sericea (Nutt.) Rydb. -- not accepted
  Berylsimpsonia B.L.Turner -- accepted
  Berylsimpsonia vanillosma (C. Wright) B.L. Turner -- accepted -- sweet yellowcrown, arctic groundsel
  Bethencourtia Choisy -- accepted
  Bethencourtia palmensis (Nees) Choisy -- accepted
  Bidens L. -- accepted -- beggarticks, Spanish needles, beggartick, devil's sticktight
  Bidens acuta (Wiegand) Britton -- not accepted
  Bidens alba (L) DC -- not accepted
  Bidens alba var. radiata (Sch. Bip.) Ballard ex T.E. Melchert -- not accepted -- romerillo, bidens
  Bidens amplectens Sherff -- accepted -- kokolau, ko`oko`olau
  Bidens amplissima Greene -- accepted -- Vancouver Island beggarticks
  Bidens aristosa (Michx.) Britton -- accepted -- bearded beggarticks, long-bracted beggar-ticks, tickseed sunflower
  Bidens aristosa var. fritcheyi Fernald -- not accepted
  Bidens aristosa var. mutica (A. Gray) Gattinger -- not accepted
  Bidens aristosa var. retrorsa (Sherff) Wunderlin -- not accepted
  Bidens asplenioides Sherff -- not accepted
  Bidens asymmetrica (Levl.) Sherff -- accepted -- Koolau Range beggarticks
  Bidens asymmetrica var. subocculata O. Deg. & Sherff -- not accepted
  Bidens aurea (Aiton) Sherff -- accepted -- Arizona beggarticks, Apache beggarticks
  Bidens aurea var. wrightii (A. Gray) Sherff -- not accepted
  Bidens awaluana O. Deg., I. Deg. & Sherff -- not accepted
  Bidens beckii Torr. ex Spreng. -- accepted -- Beck's water-marigold, Henderson's water-marigold, Oregon water-marigold
  Bidens bidentoides (Nutt.) Britton -- accepted -- Delmarva beggarticks
  Bidens bidentoides var. mariana (S.F. Blake) Sherff -- not accepted
  Bidens bigelovii A. Gray -- accepted -- Bigelow's beggarticks, Bigelow beggarticks, stickseed
  Bidens bigelovii var. angustiloba (DC.) Ballard ex T.E. Melchert -- not accepted
  Bidens bigelovii var. bigelovii A. Gray -- not accepted
  Bidens bipinnata L. -- accepted -- Spanish needles, spanish-needles
  Bidens bipinnata var. biternatoides Sherff -- not accepted
  Bidens bipinnata var. cynapiifolia (Kunth) G. Maza -- not accepted
  Bidens campylotheca Sch. Bip. -- accepted -- viper beggarticks
  Bidens campylotheca ssp. campylotheca Sch. Bip. -- accepted -- viper beggarticks
  Bidens campylotheca ssp. pentamera (Sherff) Ganders & Nagata -- accepted -- viper beggarticks, ko`oko`olau
  Bidens campylotheca ssp. waihoiensis H. St. John -- accepted -- Waihoi beggarticks, ko`oko`olau
  Bidens campylotheca var. pentamera Sherff -- not accepted
  Bidens caudatus (Kunth) Sch. Bip. -- not accepted
  Bidens cernua L. -- accepted -- nodding beggartick, nodding bur-marigold, nodding burr-marigold, bur marigold, nodding beggarticks, nodding bur marigold, sticktight, nodding burmarigold
  Bidens cernua var. cernua L. -- not accepted
  Bidens cernua var. dentata (Nutt.) B. Boivin -- not accepted
  Bidens cernua var. elata Torr. & A. Gray -- not accepted
  Bidens cernua var. elliptica Wiegand -- not accepted
  Bidens cernua var. integra Wiegand -- not accepted
  Bidens cernua var. minima (Huds.) Pursh -- not accepted
  Bidens cernua var. oligodonta Fernald & H. St. John -- not accepted
  Bidens cernua var. radiata DC. -- not accepted
  Bidens cervicata Sherff -- accepted -- Kauai beggarticks
  Bidens coartata Sherff -- not accepted
  Bidens comosa (A. Gray) Wiegand -- not accepted
  Bidens conjuncta Sherff -- accepted -- bog beggarticks, ko`oko`olau
  Bidens connata Muhl. ex Willd. -- accepted -- purplestem beggarticks, purple-stem beggarticks
  Bidens connata var. ambiversa Fassett -- not accepted
  Bidens connata var. anomala Farw. -- not accepted
  Bidens connata var. fallax (Warnst.) Sherff -- not accepted
  Bidens connata var. gracilipes Fernald -- not accepted
  Bidens connata var. inundata Fernald -- not accepted
  Bidens connata var. petiolata (Nutt.) Farw. -- not accepted
  Bidens connata var. pinnata S. Watson -- not accepted
  Bidens connata var. submutica Fassett -- not accepted
  Bidens coronata (L.) Britton -- not accepted -- crowned beggarticks
  Bidens coronata var. brachyodonta Fernald -- not accepted
  Bidens coronata var. tenuiloba (A. Gray) Sherff -- not accepted
  Bidens coronata var. trichosperma (Michx.) Fernald -- not accepted
  Bidens cosmoides (A. Gray) Sherff -- accepted -- cosmosflower beggarticks
  Bidens cosmoides var. refracta Hochr. -- not accepted
  Bidens ctenophylla Sherff -- not accepted
  Bidens cuneata Sherff -- not accepted -- cuneate bidens, wedge beggarticks
  Bidens cynapiifolia Kunth -- accepted -- West Indian beggarticks
  Bidens cynapiifolia var. portoricensis (Spreng.) O.E. Schulz -- not accepted
  Bidens cynapiifolia var. tenuis O.E. Schulz -- not accepted
  Bidens degeneri Sherff -- not accepted
  Bidens degeneri var. apioides Sherff -- not accepted
  Bidens discoidea (Torr. & A. Gray) Britton -- accepted -- small beggarticks, swamp beggar-ticks, discoid beggarticks
  Bidens distans Sherff -- not accepted
  Bidens eatonii Fernald -- accepted -- Eaton's beggarticks, Eaton's beggar-ticks, bident d'Eaton
  Bidens eatonii var. fallax Fernald -- not accepted
  Bidens eatonii var. illicita S.F. Blake -- not accepted
  Bidens eatonii var. interstes Fassett -- not accepted
  Bidens eatonii var. kennebecensis Fernald -- not accepted
  Bidens eatonii var. major Fassett -- not accepted
  Bidens eatonii var. mutabilis Fassett -- not accepted
  Bidens eatonii var. simulans Fassett -- not accepted
  Bidens elata (Torr. & A. Gray) Sherff -- not accepted
  Bidens elegans Greene -- not accepted
  Bidens fecunda O. Deg. & Sherff -- not accepted
  Bidens ferax O. Deg. & Sherff -- not accepted
  Bidens ferulifolia (Jacq.) DC. -- not accepted -- Apache beggarticks
  Bidens forbesii Sherff -- accepted -- coastal bluff beggarticks, coastalbluff beggarticks
  Bidens forbesii ssp. forbesii Sherff -- accepted -- coastal bluff beggarticks, coastalbluff beggarticks
  Bidens forbesii ssp. kahiliensis Ganders & Nagata -- accepted -- Kahili beggarticks
  Bidens frondosa L. -- accepted -- devil's beggartick, devil's-pitchfork, sticktight, bur marigold, devil's beggarticks, devil's bootjack, pitchfork weed, sticktights, tickseed sunflower
  Bidens frondosa var. anomala Porter ex Fernald -- not accepted
  Bidens frondosa var. caudata Sherff -- not accepted
  Bidens frondosa var. pallida Wiegand -- not accepted
  Bidens frondosa var. puberula Wiegand -- not accepted
  Bidens frondosa var. stenodonta Fernald & H. St. John -- not accepted
  Bidens fulvescens Sherff -- not accepted
  Bidens gardneri Baker -- accepted -- ridge beggartick
  Bidens glaucescens Greene -- not accepted
  Bidens gracilis Nutt. -- not accepted
  Bidens graciloides Sherff -- not accepted
  Bidens halawana O. Deg. & Sherff -- not accepted
  Bidens hawaiensis A. Gray -- accepted -- Hawai'i beggarticks
  Bidens heterodoxa (Fernald) Fernald & H. St. John -- accepted -- Connecticut beggarticks, Connecticut beggar-ticks, bident différent
  Bidens heterodoxa var. agnostica Fernald -- not accepted -- Connecticut beggarticks
  Bidens heterodoxa var. atheistica Fernald -- not accepted -- Connecticut beggarticks
  Bidens heterodoxa var. heterodoxa (Fernald) Fernald & St. John -- not accepted -- Connecticut beggarticks
  Bidens heterodoxa var. monardifolia Fernald -- not accepted -- Connecticut beggarticks
  Bidens heterodoxa var. orthodoxa Fernald & H. St. John -- not accepted -- Connecticut beggarticks
  Bidens heterophylla Ortega -- not accepted
  Bidens heterosperma A. Gray -- accepted -- Rocky Mountain beggarticks
  Bidens hillebrandiana (Drake) O. Deg. -- accepted -- seacliff beggarticks
  Bidens hillebrandiana ssp. hillebrandiana (Drake) O. Deg. -- accepted -- seacliff beggarticks
  Bidens hillebrandiana ssp. polycephala Nagata & Ganders -- accepted -- seacliff beggarticks
  Bidens hyperborea Greene -- accepted -- estuary beggarticks
  Bidens hyperborea var. cathancensis Fernald -- not accepted
  Bidens hyperborea var. colpophila (Fernald & H. St. John) Fernald -- not accepted
  Bidens hyperborea var. hyperborea Greene -- not accepted -- estuary beggarticks
  Bidens hyperborea var. laurentiana Fassett -- not accepted
  Bidens hyperborea var. svensonii Fassett -- not accepted -- Svenson's beggarticks
  Bidens infirma Fernald -- not accepted
  Bidens involucrata (Nutt.) Britton -- not accepted
  Bidens laevis (L.) Britton, Sterns & Poggenb. -- accepted -- smooth beggarticks, bur marigold
  Bidens lemmonii A. Gray -- accepted -- Lemmon's beggarticks
  Bidens leptocephala Sherff -- accepted -- fewflower beggarticks, few-flower beggarticks
  Bidens macrocarpa (A. Gray) Sherff -- accepted -- largefruit beggarticks
  Bidens macrocarpa var. ovatifolia (A. Gray) Sherff -- not accepted
  Bidens mariana S.F. Blake -- not accepted
  Bidens mauiensis (A. Gray) Sherff -- accepted -- Maui beggarticks
  Bidens mauiensis var. ciliata H. St. John -- not accepted
  Bidens mauiensis var. cuneatoides Sherff -- not accepted
  Bidens mauiensis var. forbesiana Sherff -- not accepted
  Bidens mauiensis var. lanaiensis Sherff -- not accepted
  Bidens mauiensis var. media Sherff -- not accepted
  Bidens megapotamica Spreng. -- not accepted
  Bidens menziesii (A. Gray) Sherff -- accepted -- Mauna Loa beggarticks
  Bidens menziesii ssp. filiformis (Sherff) Ganders & Nagata -- accepted -- Mauna Loa beggarticks
  Bidens menziesii ssp. menziesii (A. Gray) Sherff -- accepted -- Mauna Loa beggarticks
  Bidens menziesii var. filiformis Sherff -- not accepted
  Bidens menziesii var. lepida O. Deg. & Sherff -- not accepted
  Bidens menziesii var. leptondontia Sherff -- not accepted
  Bidens micrantha Gaudich. -- accepted -- grassland beggarticks
  Bidens micrantha ssp. ctenophylla (Sherff) Nagata & Ganders -- accepted -- grassland beggarticks, ko`oko`olau
  Bidens micrantha ssp. kalealaha Nagata & Ganders -- accepted -- Kalealaha beggarticks, ko`oko`olau
  Bidens micrantha ssp. micrantha Gaudich. -- accepted -- grassland beggarticks
  Bidens micrantha var. caduca (Sherff) Sherff -- not accepted
  Bidens micrantha var. kaalana Sherff -- not accepted
  Bidens micrantha var. laciniata (Hillebr.) Sherff -- not accepted
  Bidens micrantha var. rudimentifera Sherff -- not accepted
  Bidens mitis (Michx.) Sherff -- accepted -- smallfruit beggarticks
  Bidens mitis var. leptophylla (Nutt.) Small -- not accepted
  Bidens molokaiensis (Hillebr.) Sherff -- accepted -- Molokai beggarticks, wedge beggarticks
  Bidens napaliensis Sherff -- not accepted
  Bidens nashii Small -- not accepted
  Bidens nematocera (Sherff) Sherff -- not accepted
  Bidens nivea L. -- not accepted
  Bidens obtusiloba Sherff -- not accepted
  Bidens odorata Cav. -- not accepted
  Bidens pentamera (Sherff) O. Deg. & Sherff -- not accepted
  Bidens perversa O. Deg. & Sherff -- not accepted
  Bidens perversa var. aquilonalis O. Deg. & Sherff -- not accepted
  Bidens pilosa L. -- accepted -- hairy beggarticks, common beggarticks, romerillo, spanish-needles, beggar's ticks, cobbler's pegs, fisi`uli, kofe tonga, matakaro, Spanish needles
  Bidens pilosa var. bimucronata (Turcz.) Sch. Bip. -- not accepted
  Bidens pilosa var. minor (Blume) Sherff -- not accepted
  Bidens pilosa var. pilosa L. -- not accepted
  Bidens pilosa var. radiata Sch. Bip. -- not accepted
  Bidens polylepis S.F. Blake -- accepted
  Bidens polylepis var. retrorsa Sherff -- not accepted
  Bidens populifolia Sherff -- accepted -- Oahu beggarticks
  Bidens puberula (Wiegand) Rydb. -- not accepted
  Bidens pulchella (Less.) Sch. Bip. -- not accepted
  Bidens reptans (L.) G. Don -- accepted -- manzanilla trepador
  Bidens reptans var. reptans (L.) G. Don -- accepted -- manzanilla trepador
  Bidens reptans var. urbanii (Greenm.) O.E. Schulz -- not accepted -- Urban's beggartick
  Bidens salicoides Sherff -- not accepted
  Bidens sandvicensis Less. -- accepted -- shrubland beggarticks
  Bidens sandvicensis ssp. confusa Nagata & Ganders -- accepted -- shrubland beggarticks
  Bidens sandvicensis ssp. sandvicensis Less. -- accepted -- shrubland beggarticks
  Bidens sandvicensis var. antrorsa O. Deg. & Sherff -- not accepted
  Bidens sandvicensis var. caduca Sherff -- not accepted
  Bidens sandvicensis var. imminuta O. Deg. & Sherff -- not accepted
  Bidens sandvicensis var. leiocarpa O. Deg. & Sherff -- not accepted
  Bidens sandvicensis var. setosa (Sherff) Sherff -- not accepted
  Bidens scandens L. -- not accepted
  Bidens skottsbergii Sherff -- not accepted
  Bidens skottsbergii var. conglutinata (O. Deg. & Sherff) Sherff -- not accepted
  Bidens skottsbergii var. pololuensis O. Deg. & Sherff -- not accepted
  Bidens squarrosa Kunth -- accepted
  Bidens stokesii Sherff -- not accepted
  Bidens tenuisecta A. Gray -- accepted -- slimlobe beggarticks, slim-lobe beggarticks
  Bidens torta Sherff -- accepted -- corkscrew beggarticks
  Bidens trichosperma (Michx.) Britton -- accepted -- crowned beggarticks
  Bidens tripartita L. -- accepted -- threelobe beggarticks, three-lobe beggarticks
  Bidens tripartita var. heterodoxa Fernald -- not accepted
  Bidens urbanii Greenm. -- accepted -- Urban's beggartick
  Bidens valida Sherff -- accepted -- Mt. Kahili beggarticks
  Bidens vulgata Greene -- accepted -- big devil's beggartick, tall beggarticks, western sticktight
  Bidens vulgata var. puberula (Wiegand) Greene -- not accepted
  Bidens vulgata var. schizantha Lunell -- not accepted
  Bidens waianensis Sherff -- not accepted
  Bidens waimeana Sherff -- not accepted
  Bidens wiebkei Sherff -- accepted -- Wiebke's beggarticks, ko`oko`olau
  Bidens X dimidiata O. Deg. & Sherff -- not accepted
  Bidens X magnidisca O. Deg. & Sherff -- not accepted
  Bidens X micranthoides Sherff -- not accepted
  Bidens X multiceps Fassett -- accepted -- beggartick
  Bigelovia brachylepis A. Gray -- not accepted
  Bigelovia intricata A. Gray -- not accepted
  Bigelovia vaseyi A. Gray -- not accepted
  Bigelowia DC. -- accepted -- rayless goldenrod
  Bigelowia nudata (Michx.) DC. -- accepted -- pineland rayless goldenrod
  Bigelowia nudata ssp. australis L.C. Anderson -- not accepted -- pineland rayless goldenrod
  Bigelowia nudata ssp. nudata (Michx.) DC. -- not accepted -- pineland rayless goldenrod
  Bigelowia nudata var. australis (L.C. Anderson) Shinners -- accepted -- pineland rayless goldenrod
  Bigelowia nudata var. nudata (Michx.) DC. -- accepted -- pineland rayless goldenrod
  Bigelowia nuttallii L.C. Anderson -- accepted -- Nuttall's rayless goldenrod
  Bigelowia virgata (Nutt.) DC. -- not accepted
  Blennosperma Less. -- accepted -- stickyseed
  Blennosperma bakeri Heiser -- accepted -- Baker's stickyseed, Sonoma sunshine
  Blennosperma nanum (Hook.) S.F. Blake -- accepted -- common stickyseed
  Blennosperma nanum var. nanum (Hook.) S.F. Blake -- accepted -- common stickyseed
  Blennosperma nanum var. robustum J.T. Howell -- accepted -- common stickyseed
  Blepharipappus Hook. -- accepted -- blepharipappus
  Blepharipappus scaber Hook. -- accepted -- rough eyelashweed, blepharipappus
  Blepharipappus scaber ssp. laevis (A. Gray) D.D. Keck -- not accepted -- rough eyelashweed
  Blepharipappus scaber ssp. scaber Hook. -- not accepted -- rough eyelashweed
  Blepharizonia Greene -- accepted -- blepharizonia
  Blepharizonia laxa Greene -- accepted -- big tarweed
  Blepharizonia plumosa (Kellogg) Greene -- accepted -- big tarweed
  Blepharizonia plumosa ssp. plumosa (Kellogg) Greene -- accepted -- big tarweed
  Blepharizonia plumosa ssp. viscida D.D. Keck -- not accepted -- big tarweed
  Blumea DC. -- accepted -- false oxtongue
  Blumea balsamifera (L) DC -- accepted -- ngai camphor, nagi camphor
  Blumea lacera (Burm. f.) DC. -- accepted -- blumea
  Blumea laciniata (Roxb.) DC. -- accepted -- cutleaf false oxtongue
  Blumea sessiliflora Decne. -- accepted -- sessileleaf false oxtongue
  Blumea viscosa (Mill.) Badillo -- accepted -- clammy false oxtongue
  Boebera papposa (Vent.) Rydb. ex Britton -- not accepted
  Bolophyta alpina Nutt. -- not accepted
  Bolophyta ligulata (M.E. Jones) W.A. Weber -- not accepted
  Bolophyta tetraneuris (Barneby) W.A. Weber -- not accepted
  Boltonia L'Hér. -- accepted -- doll's daisy
  Boltonia apalachicolensis L.C. Anderson -- accepted -- Apalachicola doll's daisy
  Boltonia asteroides (L.) L'Hér. -- accepted -- white doll's daisy, star boltonia, white doll's-daisy
  Boltonia asteroides var. asteroides (L.) L'Hér. -- accepted -- white doll's daisy
  Boltonia asteroides var. decurrens (Torr. & A. Gray) Fernald -- not accepted
  Boltonia asteroides var. glastifolia (Hill) Fernald -- not accepted
  Boltonia asteroides var. latisquama (A. Gray) Cronquist -- accepted -- white doll's daisy, white doll's-daisy
  Boltonia asteroides var. recognita (Fernald & Grisc.) Cronquist -- accepted -- white doll's daisy, white doll's-daisy
  Boltonia caroliniana (Walter) Fernald -- accepted -- Carolina doll's daisy
  Boltonia decurrens (Torr. & A. Gray) Alph. Wood -- accepted -- claspingleaf doll's daisy, decurrent false aster
  Boltonia diffusa Elliot -- accepted -- smallhead doll's daisy
  Boltonia diffusa var. diffusa Elliot -- accepted -- smallhead doll's daisy
  Boltonia diffusa var. interior Fernald & Grisc. -- accepted -- smallhead doll's daisy
  Boltonia interior (Fernald & Grisc.) G.N. Jones -- not accepted
  Boltonia latisquama A. Gray -- not accepted
  Boltonia latisquama var. decurrens (Torr. & A. Gray) Fernald & Grisc. -- not accepted
  Boltonia latisquama var. microcephala Fernald & Grisc. -- not accepted
  Boltonia latisquama var. occidentalis A. Gray -- not accepted
  Boltonia latisquama var. recognita Fernald & Grisc. -- not accepted
  Boltonia lautureana Debeaux -- accepted
  Boltonia ravenelii Fernald & Grisc. -- not accepted
  Boltonia recognita (Fernald & Grisc.) G.N. Jones -- not accepted
  Bombycilaena DC. -- accepted
  Bombycilaena californica (Fisch. & C.A. Mey.) Holub -- accepted -- false cottonseed
  Bombycilaena californica var. californica (Fisch. & C.A. Mey.) Holub -- not accepted
  Bombycilaena californica var. subvestita (A. Gray) Kartesz -- not accepted
  Borrichia Adans. -- accepted -- seaside tansy
  Borrichia arborescens (L) DC -- accepted -- tree seaside tansy
  Borrichia frutescens (L) DC -- accepted -- bushy seaside tansy, bushy seaoxeye
  Borrichia X cubana Britton & S.F. Blake (pro sp.) -- accepted -- Cuban borrichia
  Brachyactis Ledeb. -- not accepted -- rayless aster
  Brachyactis angusta (Lindl.) Britton -- not accepted
  Brachyactis ciliata (Ledeb.) Ledeb. -- not accepted -- alkali rayless aster
  Brachyactis ciliata ssp. angusta (Lindl.) A.G. Jones -- not accepted -- alkali rayless aster
  Brachyactis frondosa (Nutt.) A. Gray -- not accepted -- leafy rayless aster
  Brachychaeta sphacelata (Raf.) Britton -- not accepted
  Brachyris dracunculoides DC. -- not accepted
  Brachyris microcephala DC. -- not accepted
  Bracteantha Anderb. & Heagi -- not accepted
  Bracteantha bracteata (Vent.) Anderb. & Heagi -- not accepted
  Bracyrhamphus intybaceus (Jacq.) DC. -- not accepted
  Bradburia Torr. & A.Gray -- accepted -- bradburia
  Bradburia hirtella Torr. & A. Gray -- accepted -- Texas chrysopsis
  Bradburia pilosa (Nutt.) Semple -- accepted -- soft goldenaster
  Brauneria angustifolia (DC.) A. Heller -- not accepted
  Brauneria pallida (Nutt.) Britton -- not accepted
  Brauneria purpurea (L.) Britton -- not accepted
  Breea arvensis (L.) Less. -- not accepted
  Breea incana (S.G. Gmel.) W.A. Weber -- not accepted
  Brickellia Elliot -- accepted -- brickellbush, brickelbush, brickellia
  Brickellia amplexicaulis B.L. Rob. -- accepted -- earleaf brickellbush, ear-leaf brickellbush
  Brickellia amplexicaulis var. amplexicaulis B.L. Rob. -- not accepted -- earleaf brickellbush
  Brickellia amplexicaulis var. lanceolata (A. Gray) B.L. Rob. -- not accepted -- earleaf brickellbush
  Brickellia arguta B.L. Rob. -- not accepted -- pungent brickellbush, spearleaf brickellia
  Brickellia arguta var. arguta B.L. Rob. -- not accepted -- pungent brickellbush, spearleaf brickellia
  Brickellia arguta var. odontolepis B.L. Rob. -- not accepted -- pungent brickellbush
  Brickellia atractyloides A. Gray -- accepted -- spearleaf brickellbush, hollyleaf brickellbush
  Brickellia atractyloides var. arguta (B.L. Rob.) Jeps. -- accepted -- pungent brickellbush
  Brickellia atractyloides var. atractyloides A. Gray -- accepted -- spearleaf brickellia
  Brickellia atractyloides var. odontolepis (B.L. Rob.) Jeps. -- accepted -- pungent brickellbush
  Brickellia baccharidea A. Gray -- accepted -- resinleaf brickellbush, baccharisleaf brickellbush, baccharis-leaf brickellia
  Brickellia betonicifolia A. Gray -- accepted -- betonyleaf brickellbush
  Brickellia brachiata A. Gray -- not accepted
  Brickellia brachyphylla (A. Gray) A. Gray -- accepted -- plumed brickellbush, Brach brickellbush
  Brickellia brachyphylla var. brachyphylla (A. Gray) A. Gray -- not accepted -- plumed brickellbush
  Brickellia brachyphylla var. hinckleyi (Standl.) Flyr -- not accepted -- Hinckley's brickellia
  Brickellia brachyphylla var. terlinguensis Flyr -- not accepted -- Terlingu brickellia
  Brickellia californica (Torr. & A. Gray) A. Gray -- accepted -- California brickellbush, Jepson's brickellbush
  Brickellia californica var. californica (Torr. & A. Gray) A. Gray -- not accepted -- California brickellbush
  Brickellia californica var. desertorum (Coville) Parish ex H.M. Hall -- not accepted
  Brickellia californica var. jepsonii B.L. Rob. -- not accepted -- Jepson's brickellbush
  Brickellia chenopodina (Greene) B.L. Rob. -- accepted -- chenopod brickellbush
  Brickellia chlorolepis (Woot. & Standl.) Shinners -- not accepted
  Brickellia conduplicata (B.L. Rob.) B.L. Rob. -- not accepted -- southwestern brickellbush
  Brickellia cordifolia Elliot -- accepted -- Flyr's nemesis
  Brickellia coulteri A. Gray -- accepted -- Coulter's brickellbush
  Brickellia coulteri var. brachiata (A. Gray) B.L. Turner -- accepted
  Brickellia coulteri var. coulteri A. Gray -- accepted -- Coulter's brickellbush
  Brickellia cylindracea A. Gray & Engelm. -- accepted -- gravelbar brickellbush
  Brickellia dentata (DC.) Sch. Bip. -- accepted -- leafy brickellbush, leafy brickellia
  Brickellia desertorum Coville -- accepted -- desert brickellbush
  Brickellia diffusa (Vahl) A. Gray -- accepted
  Brickellia eupatorioides (L.) Shinners -- accepted -- false boneset
  Brickellia eupatorioides var. chlorolepis (Woot. & Standl.) B.L. Turner -- accepted -- false boneset
  Brickellia eupatorioides var. corymbulosa (Torr. & A. Gray) Shinners -- accepted -- false boneset
  Brickellia eupatorioides var. eupatorioides (L.) Shinners -- accepted -- false boneset
  Brickellia eupatorioides var. floridana (R.W. Long) B.L. Turner -- accepted -- false boneset
  Brickellia eupatorioides var. gracillima (A. Gray) B.L. Turner -- accepted -- false boneset
  Brickellia eupatorioides var. ozarkana (Shinners) Shinners -- not accepted
  Brickellia eupatorioides var. texana (Shinners) Shinners -- accepted -- false boneset
  Brickellia fendleri A. Gray -- not accepted -- Fendler's brickellbush
  Brickellia floribunda A. Gray -- accepted -- Chihuahuan brickellbush, desert brickellbush
  Brickellia frutescens A. Gray -- accepted -- shrubby brickellbush, rigid brickellbush
  Brickellia grandiflora (Hook.) Nutt. -- accepted -- tasselflower brickellbush, mountain brickellbush, tasselflower brickellia
  Brickellia grandiflora var. petiolaris A. Gray -- not accepted
  Brickellia greenei A. Gray -- accepted -- Greene's brickellbush
  Brickellia hinckleyi Standl. -- accepted -- Hinckley's brickellbush
  Brickellia hinckleyi var. hinckleyi Standl. -- accepted -- Hinckley's brickellbush, Hinckley's brickellia
  Brickellia hinckleyi var. terlinguensis (Flyr) B.L. Turner -- accepted -- Terlingu brickellia
  Brickellia incana A. Gray -- accepted -- woolly brickellbush, white brickellbush
  Brickellia knappiana E. Drew -- accepted -- Knapp's brickellbush
  Brickellia laciniata A. Gray -- accepted -- splitleaf brickellbush
  Brickellia lemmonii A. Gray -- accepted -- Lemmon's brickellbush
  Brickellia lemmonii var. conduplicata (B.L. Rob.) B.L. Turner -- accepted -- southwestern brickellbush, Tierra Vieja brickellbush
  Brickellia lemmonii var. lemmonii A. Gray -- accepted -- Lemmon's brickellbush
  Brickellia lemmonii var. nelsonii (B.L. Rob.) B.L. Turner -- not accepted
  Brickellia lemmonii var. wootonii (Greene) B.L. Rob. -- not accepted -- Lemmon's brickellbush
  Brickellia leptophylla (Scheele) Shinners -- not accepted
  Brickellia leptophylla var. mexicana (Shinners) Shinners -- not accepted
  Brickellia linifolia D.C. Eaton -- not accepted
  Brickellia longifolia S. Watson -- accepted -- longleaf brickellbush, long leaf brickellbush
  Brickellia longifolia var. longifolia S. Watson -- accepted -- longleaf brickellbush
  Brickellia longifolia var. multiflora (Kellogg) Cronquist -- accepted -- longleaf brickellbush, gumleaf brickellbush
  Brickellia microphylla (Nutt.) A. Gray -- accepted -- littleleaf brickellbush
  Brickellia microphylla ssp. scabra (A. Gray) W.A. Weber -- not accepted
  Brickellia microphylla var. microphylla (Nutt.) A. Gray -- accepted -- littleleaf brickellbush, Watson's brickellbush
  Brickellia microphylla var. scabra A. Gray -- accepted -- rough brickellbush
  Brickellia microphylla var. watsonii (B.L. Rob.) S.L. Welsh -- not accepted -- Watson's brickellbush
  Brickellia mosieri (Small) Shinners -- not accepted -- Florida brickell-bush
  Brickellia multiflora Kellogg -- not accepted
  Brickellia nelsonii B.L. Rob. -- not accepted -- Nelson's brickellbush
  Brickellia nevinii A. Gray -- accepted -- Nevin's brickellbush
  Brickellia oblongifolia Nutt. -- accepted -- Mojave brickellbush, narrowleaf brickellbush, Mohave brickellbush
  Brickellia oblongifolia var. linifolia (D.C. Eaton) B.L. Rob. -- accepted -- narrowleaf brickellbush, narrow leaf brickellbush
  Brickellia oblongifolia var. oblongifolia Nutt. -- accepted -- Mojave brickellbush, narrowleaf brickellbush
  Brickellia oblongifolia var. typica B.L. Rob. -- not accepted
  Brickellia parvula A. Gray -- accepted -- Mt. Davis brickellbush, small brickellbush, small brickellia
  Brickellia pringlei A. Gray -- accepted -- Pringle's brickellbush
  Brickellia rosemarinifolia (Vent.) W.A. Weber -- not accepted
  Brickellia rosemarinifolia var. chlorolepis (Woot. & Standl.) W.A. Weber -- not accepted
  Brickellia rosmarinifolia (Vent.) W.A. Weber -- not accepted
  Brickellia rosmarinifolia ssp. chlorolepis (Woot. & Standl.) W.A. Weber -- not accepted
  Brickellia rusbyi A. Gray -- accepted -- stinking brickellbush
  Brickellia scabra (A. Gray) A. Nelson ex B.L. Rob. -- not accepted
  Brickellia shaffneri (A. Gray) Shinners -- not accepted
  Brickellia shineri M.E. Jones ex Flyr -- not accepted
  Brickellia simplex A. Gray -- accepted -- Sonoran brickellbush
  Brickellia squamulosa A. Gray -- not accepted -- Mule Mountain brickellbush
  Brickellia venosa (Woot. & Standl.) B.L. Rob. -- accepted -- veiny brickellbush
  Brickellia veronicifolia (Kunth) A. Gray -- accepted -- veronicaleaf brickellbush
  Brickellia veronicifolia var. petrophila (B.L. Rob.) B.L. Rob. -- not accepted -- veronicaleaf brickellbush
  Brickellia veronicifolia var. veronicifolia (Kunth) A. Gray -- not accepted -- veronicaleaf brickellbush
  Brickellia viejensis Flyr -- not accepted -- Tierra Vieja brickellbush
  Brickellia watsonii B.L. Rob. -- not accepted
  Brickelliastrum King & H. Rob. -- accepted -- brickellbush
  Brickelliastrum fendleri (A. Gray) King & H. Rob. -- accepted -- Fendler's brickellbush
  Brintonia Greene -- accepted -- mock goldenrod
  Brintonia discoidea (Elliott) Greene -- accepted -- rayless mock goldenrod
  Bulbostylis annua Nutt. -- not accepted
  Buphthalmum L. -- accepted -- ox eye
  Buphthalmum arborescens L. -- not accepted
  Buphthalmum salicifolium L. -- accepted -- ox-eye
  Cacalia atriplicifolia L. -- not accepted
  Cacalia auriculata DC. -- not accepted -- cacalia
  Cacalia auriculata ssp. kamtschatica (Maxim.) Hultén -- not accepted
  Cacalia coccinea Sims -- not accepted
  Cacalia cordifolia L. f. -- not accepted
  Cacalia decomposita A. Gray -- not accepted
  Cacalia diversifolia Torr. & A. Gray -- not accepted
  Cacalia elliottii (Harper) Shinners -- not accepted
  Cacalia floridana A. Gray -- not accepted
  Cacalia kamtschatica (Maxim.) Kudo -- not accepted
  Cacalia lanceolata Nutt. -- not accepted
  Cacalia lanceolata var. elliottii (Harper) Kral & R.K. Godfrey -- not accepted
  Cacalia lanceolata var. virescens (Harper) Shinners -- not accepted
  Cacalia muehlenbergii (Sch. Bip.) Fernald -- not accepted
  Cacalia nardosmia A. Gray -- not accepted
  Cacalia nardosmia var. glabrata (Piper) B. Boivin -- not accepted
  Cacalia ovata Walter -- not accepted
  Cacalia paniculata Raf. -- not accepted
  Cacalia plantaginea (Raf.) Shinners -- not accepted
  Cacalia porophyllum L. -- not accepted
  Cacalia pteranthes Raf. -- not accepted
  Cacalia reniformis Muhl. ex Willd. non Cacalia reniformis Lam. -- not accepted
  Cacalia rotundifolia (Raf.) House -- not accepted
  Cacalia rugelia (A. Gray) T.M. Barkley & Cronquist -- not accepted
  Cacalia sonchifolia L. -- not accepted
  Cacalia suaveolens L. -- not accepted
  Cacalia sulcata Fernald -- not accepted
  Cacalia tuberosa Nutt. -- not accepted
  Cacaliopsis A. Gray -- accepted -- cacaliopsis
  Cacaliopsis nardosmia (A. Gray) A. Gray -- accepted -- silvercrown
  Cacaliopsis nardosmia var. glabrata Piper -- not accepted
  Calea aspera Jacq. -- not accepted
  Calea oppositifolia L. -- not accepted
  Calendula L. -- accepted -- marigold
  Calendula arvensis L. -- accepted -- field marigold
  Calendula officinalis L. -- accepted -- pot marigold, Scotch-marigold, calendula
  Calendula officinalis var. prolifera hort. -- not accepted
  Calliopsis basalis A. Dietr. -- not accepted
  Callistephus Cass. -- accepted -- callistephus
  Callistephus chinensis (L.) Nees -- accepted -- China aster
  Calotis R. Br. -- accepted -- calotis
  Calotis cuneifolia R. Br. -- accepted -- wedgeleaf
  Calycadenia DC. -- accepted -- western rosinweed
  Calycadenia campestris Greene -- not accepted
  Calycadenia ciliosa Greene -- not accepted
  Calycadenia elegans Greene -- not accepted
  Calycadenia fremontii A. Gray -- accepted -- Fremont's western rosinweed
  Calycadenia hispida (Greene) Greene -- not accepted
  Calycadenia hispida ssp. hispida (Greene) Greene -- not accepted -- hispid western rosinweed
  Calycadenia hispida ssp. reducta D.D. Keck -- not accepted
  Calycadenia hooveri G.D. Carr -- accepted -- Hoover's western rosinweed
  Calycadenia micrantha R.L. Carr & G.D. Carr -- accepted -- Oregon western rosinweed
  Calycadenia mollis A. Gray -- accepted -- soft western rosinweed
  Calycadenia multiglandulosa DC. -- accepted -- sticky western rosinweed
  Calycadenia multiglandulosa ssp. bicolor (Greene) D.D. Keck -- not accepted
  Calycadenia multiglandulosa ssp. cephalotes (DC.) D.D. Keck -- not accepted
  Calycadenia multiglandulosa ssp. robusta D.D. Keck -- not accepted
  Calycadenia oppositifolia (Greene) Greene -- accepted -- Butte County western rosinweed
  Calycadenia pauciflora A. Gray -- accepted -- smallflower western rosinweed
  Calycadenia pauciflora var. elegans (Greene) Jeps. -- not accepted
  Calycadenia ramulosa Greene -- not accepted
  Calycadenia scabrella (E. Drew) Greene -- not accepted
  Calycadenia spicata (Greene) Greene -- accepted -- spiked western rosinweed
  Calycadenia tenella (Nutt.) Torr. & A. Gray -- not accepted
  Calycadenia truncata DC. -- accepted -- Oregon western rosinweed
  Calycadenia truncata ssp. microcephala H.M. Hall ex D.D. Keck -- not accepted -- Oregon western rosinweed
  Calycadenia truncata ssp. scabrella (E. Drew) D.D. Keck -- not accepted -- Oregon western rosinweed
  Calycadenia truncata ssp. truncata DC. -- accepted -- Oregon western rosinweed
  Calycadenia truncata var. scabrella (E. Drew) Jeps. -- not accepted
  Calycadenia villosa DC. -- accepted -- dwarf western rosinweed
  Calycoseris A. Gray -- accepted -- tackstem
  Calycoseris parryi A. Gray -- accepted -- yellow tackstem
  Calycoseris wrightii A. Gray -- accepted -- white tackstem
  Calymmandra candida Torr. & A. Gray -- not accepted
  Calyptocarpus Less. -- accepted -- calyptocarpus
  Calyptocarpus blepharolepis B.L. Rob. -- not accepted
  Calyptocarpus vialis Less. -- accepted -- straggler daisy
  Canadanthus G.L. Nesom -- accepted -- mountain aster
  Canadanthus modestus (Lindl.) G.L. Nesom -- accepted -- giant mountain aster
  Carduus L. -- accepted -- plumeless thistle
  Carduus acanthoides L. -- accepted -- spiny plumeless thistle, plumeless thistle, spiny plumeless-thistle
  Carduus acanthoides ssp. acanthoides L. -- accepted
  Carduus altissimus L. -- not accepted
  Carduus americanus (A. Gray) Rydb. -- not accepted
  Carduus araneosus Osterh. -- not accepted
  Carduus arvensis (L.) Robson -- not accepted
  Carduus austrinus Small -- not accepted
  Carduus carolinianus Walter -- not accepted
  Carduus coloradensis Rydb. -- not accepted
  Carduus crispus L. -- accepted -- curly plumeless thistle, curly plumeless-thistle, curled thistle, welted thistle
  Carduus discolor (Muhl. ex Willd.) Nutt. -- not accepted
  Carduus helenioides L. -- not accepted
  Carduus helenoides L. orth. var. -- not accepted
  Carduus helleri Small -- not accepted
  Carduus inamoenus Greene -- not accepted
  Carduus lanceolatus L. -- not accepted
  Carduus lecontei (Torr. & A. Gray) Pollard -- not accepted
  Carduus macounii Greene -- not accepted
  Carduus macrocephalus Desf. -- not accepted
  Carduus macrolepis Peterm. -- not accepted
  Carduus marianus L. -- not accepted
  Carduus muticus (Michx.) Pers. -- not accepted
  Carduus nevadensis Greene -- not accepted
  Carduus nutans L. -- accepted -- nodding plumeless thistle, nodding thistle, musk thistle, nodding plumeless-thistle, chardon penche, plumeless thistle
  Carduus nutans ssp. leiophyllus (Petrovic) Stojanov & Stef. -- not accepted -- nodding plumeless thistle, nodding thistle, musk thistle
  Carduus nutans ssp. macrocephalus (Desf.) Nyman -- not accepted -- nodding plumeless thistle, musk thistle, nodding thistle
  Carduus nutans ssp. macrolepis (Peterm.) Kazmi -- not accepted -- nodding plumeless thistle, musk thistle, nodding thistle
  Carduus nutans ssp. nutans L. -- not accepted -- nodding plumeless thistle, musk thistle, nodding thistle
  Carduus nutans var. leiophyllus (Petrovic) Arčnes -- not accepted
  Carduus nutans var. macrocephalus (Desf.) B. Boivin -- not accepted
  Carduus nutans var. vestitus (H.M. Hallier) B. Boivin -- not accepted
  Carduus nuttallii (DC.) Pollard -- not accepted
  Carduus pinetorum Small -- not accepted
  Carduus pulchellus Greene -- not accepted
  Carduus pumilus Nutt. -- not accepted
  Carduus pycnocephalus L. -- accepted -- Italian plumeless thistle, Italian thistle, compact-headed thistle
  Carduus repandus (Michx.) Pers. -- not accepted
  Carduus smallii (Britton) H.E. Ahles -- not accepted
  Carduus spathulatus Osterh. -- not accepted
  Carduus spinosissimus Walter -- not accepted
  Carduus tenuiflorus W. Curtis -- accepted -- winged plumeless thistle, Italian thistle, slenderflower thistle, slender-flowered thistle, winged thistle
  Carduus thoermeri Weinm. -- not accepted
  Carduus tracyi Rydb. -- not accepted
  Carduus truncatus Greene -- not accepted
  Carduus undulatus Nutt. -- not accepted
  Carduus undulatus var. canescens (Nutt.) Porter -- not accepted
  Carduus virginianus L. -- not accepted
  Carduus vulgaris Savi -- not accepted
  Carduus X orthocephalus Wallr. -- accepted -- plumeless thistle
  Carlina L. -- accepted -- carline thistle
  Carlina vulgaris L. -- accepted -- carline thistle
  Carlina vulgaris ssp. longifolia Nyman -- not accepted -- carline thistle
  Carlina vulgaris ssp. vulgaris L. -- accepted -- carline thistle
  Carlquistia B.G. Baldw. -- accepted
  Carlquistia muirii (A. Gray) B.G. Baldw. -- accepted -- Muir's raillardiopsis
  Carminatia Moc. ex DC. -- accepted -- carminatia
  Carminatia tenuiflora DC. -- accepted -- plumeweed
  Carphephorus Cass. -- accepted -- chaffhead
  Carphephorus bellidifolius (Michx.) Torr. & A. Gray -- accepted -- sandywoods chaffhead
  Carphephorus carnosus (Small) C.W. James -- accepted -- pineland chaffhead
  Carphephorus corymbosus (Nutt.) Torr. & A. Gray -- accepted -- coastal plain chaffhead, coastalplain chaffhead
  Carphephorus odoratissimus (J.F. Gmel.) Herbert -- accepted -- vanillaleaf
  Carphephorus odoratissimus var. odoratissimus (J.F. Gmel.) Herbert -- accepted
  Carphephorus odoratissimus var. subtropicanus (J.F. Gmel.) Herbert -- accepted
  Carphephorus paniculatus (J.F. Gmel.) Herbert -- accepted -- hairy chaffhead
  Carphephorus pseudoliatris Cass. -- accepted -- bristleleaf chaffhead
  Carphephorus tomentosus (Michx.) Torr. & A. Gray -- accepted -- woolly chaffhead
  Carphephorus tomentosus var. walteri (Elliot) Fernald -- not accepted
  Carphochaete A. Gray -- accepted -- bristlehead
  Carphochaete bigelovii A. Gray -- accepted -- Bigelow's bristlehead, Bigelow bush
  Carthamus L. -- accepted -- distaff thistle
  Carthamus baeticus (Boiss. & Reut.) Nyman -- not accepted -- smooth distaff thistle
  Carthamus creticus L. -- accepted -- woolly distaff thistle
  Carthamus laevis Hill -- not accepted
  Carthamus lanatus L. -- accepted -- woolly distaff thistle, distaff thistle, saffron thistle
  Carthamus lanatus ssp. baeticus (Boiss. & Reut.) Maire -- not accepted -- woolly distaff thistle, saffron thistle, smooth distaff thistle
  Carthamus lanatus ssp. creticus (L.) Holmboe -- not accepted
  Carthamus lanatus ssp. lanatus L. -- not accepted -- woolly distaff thistle
  Carthamus leucocaulos Sm. -- accepted -- whitestem distaff thistle, distaff thistle, glaucous star thistle
  Carthamus oxyacantha M. Bieb. -- not accepted -- jeweled distaff thistle, wild safflower
  Carthamus oxyacanthus M. Bieb. -- accepted -- jeweled distaff thistle, wild safflower
  Carthamus tinctorius L. -- accepted -- safflower
  Castalis Cass. -- accepted -- castalis
  Castalis tragus (Aiton) Norl. -- not accepted -- Cape marigold, Cape-marigold
  Catananche L. -- accepted
  Catananche caerulea L. -- accepted
  Celmisia Cass. -- accepted -- celmisia
  Celmisia spectabilis Hook. f. -- accepted
  Centaurea L. -- accepted -- knapweed, star thistle
  Centaurea americana Nutt. -- not accepted -- American basketflower, American star thistle, American star-thistle
  Centaurea aspera L. -- accepted -- rough star-thistle
  Centaurea austriaca Willd. -- not accepted
  Centaurea babylonica (L.) L. -- accepted -- Syrian knapweed
  Centaurea benedicta (L.) L. -- accepted -- blessed thistle
  Centaurea besseriana DC. -- not accepted
  Centaurea biebersteinii DC. -- not accepted -- spotted knapweed
  Centaurea bovina Velen. -- accepted -- pasture knapweed
  Centaurea calcitrapa L. -- accepted -- red star-thistle, purple starthistle, red star thistle
  Centaurea calcitrapoides L. -- accepted -- smallhead star-thistle
  Centaurea cineraria L. -- accepted -- dusty miller
  Centaurea cyanus L. -- accepted -- garden cornflower, cornflower, bachelor's button
  Centaurea dealbata Willd. -- accepted -- whitewash cornflower
  Centaurea debeauxii Gren. & Godr. -- accepted -- meadow knapweed
  Centaurea debeauxii ssp. thuillieri Dostál -- not accepted -- meadow knapweed
  Centaurea depressa M. Bieb. -- accepted -- Iranian knapweed, centaurea
  Centaurea diffusa Lam. -- accepted -- diffuse knapweed, white knapweed
  Centaurea diluta Aiton -- accepted -- North African knapweed
  Centaurea dubia Suter -- not accepted
  Centaurea dubia ssp. vochinensis (Bernh. ex Rchb.) Hayek -- not accepted
  Centaurea eriophora L. -- accepted -- wild sandheath
  Centaurea iberica Trevir. ex Spreng. -- accepted -- Iberian knapweed, Iberian starthistle, Iberian star thistle
  Centaurea jacea L. -- accepted -- brownray knapweed, brown knapweed
  Centaurea macrocephala Puschk. ex Willd. -- accepted -- bighead knapweed, big yellow centaurea, big-headed knapweed
  Centaurea maculosa auct. non Lam. -- not accepted -- spotted knapweed
  Centaurea melitensis L. -- accepted -- Maltese star-thistle, Malta starthistle, spotted knapweed, tocalote, Maltese star thistle, Napa thistle
  Centaurea montana L. -- accepted -- mountain knapweed, perennial cornflower, mountain-bluet
  Centaurea montana var. alba hort. -- not accepted
  Centaurea moschata L. -- not accepted
  Centaurea muricata L. -- not accepted
  Centaurea nervosa Willd. -- accepted -- singleflower knapweed
  Centaurea nigra L. -- accepted -- lesser knapweed, black knapweed
  Centaurea nigra var. radiata DC. -- not accepted
  Centaurea nigrescens Willd. -- accepted -- Tyrol knapweed, alpine knapweed, short-fringed knapweed, vochin knapweed
  Centaurea orientalis L. -- accepted
  Centaurea ovina Pall. ex Willd. -- accepted -- lilac knapweed
  Centaurea ovina ssp. besseriana (DC.) Dostál -- accepted -- lilac knapweed
  Centaurea paniculata L. -- accepted -- Jersey knapweed
  Centaurea phrygia L. -- accepted -- wig knapweed
  Centaurea picris Pall. ex Willd. -- not accepted -- Russian knapweed
  Centaurea pratensis Thuill. non Salisb. -- not accepted -- meadow knapweed
  Centaurea repens L. -- not accepted -- Russian knapweed, hardheads
  Centaurea rothrockii Greenm. -- not accepted -- Rothrock's knapweed
  Centaurea salmantica L. -- not accepted
  Centaurea scabiosa L. -- accepted -- greater knapweed, scabious knapweed, greater centaury
  Centaurea scabiosa var. vertesensis (Boros) Soo -- not accepted
  Centaurea solstitialis L. -- accepted -- yellow star-thistle, yellow starthistle, yellow star thistle
  Centaurea squarrosa Willd. -- not accepted -- squarrose knapweed
  Centaurea stoebe L. -- accepted -- spotted knapweed
  Centaurea stoebe ssp. micranthos (Gugler) Hayek -- accepted -- spotted knapweed
  Centaurea stoebe ssp. stoebe L. -- accepted -- spotted knapweed
  Centaurea sulphurea Willd. -- accepted -- sulphur knapweed
  Centaurea transalpina auct. non Schleich. ex DC. -- not accepted -- alpine knapweed
  Centaurea trichocephala M. Bieb. ex Willd. -- accepted -- feather-head knapweed, feather-headed knapweed
  Centaurea triumfettii All. -- accepted -- squarrose knapweed
  Centaurea triumfettii auct. non All. -- not accepted
  Centaurea uniflora Turra -- accepted -- singleflower knapweed
  Centaurea uniflora ssp. nervosa (Willd.) Bonnier & Layens -- not accepted -- singleflower knapweed
  Centaurea variegata Lam. -- not accepted
  Centaurea virgata Lam. -- accepted -- squarrose knapweed
  Centaurea virgata ssp. squarrosa (Willd.) Gugler -- accepted -- squarrose knapweed
  Centaurea virgata ssp. virgata Lam. -- accepted -- squarrose knapweed
  Centaurea virgata var. squarrosa (Willd.) Boiss. -- not accepted -- squarrose knapweed
  Centaurea vochinensis auct. non Bernh. ex Rchb. -- not accepted
  Centaurea X moncktonii C.E. Britton -- accepted -- meadow knapweed, protean knapweed
  Centaurea X pouzinii DC. -- accepted
  Centaurea X psammogena G. Gáyer -- accepted
  Centipeda Lour. -- accepted -- centipeda
  Centipeda minima (L.) A. Braun & Asch. -- accepted -- spreading sneezeweed
  Centratherum Cass. -- accepted -- centratherum
  Centratherum punctatum Cass. -- accepted -- larkdaisy
  Centromadia Greene -- accepted
  Centromadia fitchii (A. Gray) Greene -- accepted -- Fitch's tarweed
  Centromadia parryi (Greene) Greene -- accepted -- Parry's false tarplant
  Centromadia parryi ssp. australis (D.D. Keck) B.G. Baldw. -- accepted -- pappose tarweed
  Centromadia parryi ssp. congdonii (B.L. Rob. & Greenm.) B.G. Baldw. -- accepted -- Congdon's tarweed
  Centromadia parryi ssp. parryi (Greene) Greene -- accepted -- pappose tarweed
  Centromadia parryi ssp. rudis (Greene) B.G. Baldw. -- accepted -- pappose tarweed
  Centromadia pungens (Hook. & Arn.) Greene -- accepted -- pungent false tarplant
  Centromadia pungens ssp. laevis (D.D. Keck) B.G. Baldw. -- accepted -- common tarweed
  Centromadia pungens ssp. maritima (Greene) B.G. Baldw. -- not accepted
  Centromadia pungens ssp. pungens (Hook. & Arn.) Greene -- accepted -- common tarweed
  Centromadia pungens ssp. septentrionalis (D.D. Keck) B.G. Baldw. -- not accepted
  Chaenactis DC. -- accepted -- pincushion, chaenactis
  Chaenactis alpigena C.W. Sharsmith -- accepted -- southern Sierra pincushion, Sierra pincushion
  Chaenactis alpina (A. Gray) M.E. Jones -- not accepted
  Chaenactis alpina var. leucopsis (Greene) Cockerell ex Stockw. -- not accepted
  Chaenactis alpina var. rubella (Greene) Stockw. -- not accepted
  Chaenactis angustifolia Greene -- not accepted
  Chaenactis artemisiifolia (Harv. & A. Gray ex A. Gray) A. Gray -- accepted -- white pincushion
  Chaenactis brachiata Greene -- not accepted
  Chaenactis brachiata var. stansburiana Stockw. -- not accepted
  Chaenactis carphoclinia A. Gray -- accepted -- pebble pincushion
  Chaenactis carphoclinia var. attenuata (A. Gray) M.E. Jones -- not accepted
  Chaenactis carphoclinia var. carphoclinia A. Gray -- accepted -- pebble pincushion, Peeble pincushion
  Chaenactis carphoclinia var. peirsonii (Jeps.) Munz -- accepted -- Peirson's pincushion
  Chaenactis cineria Stockw. -- not accepted
  Chaenactis cusickii A. Gray -- accepted -- Cusick's pincushion
  Chaenactis douglasii (Hook.) Hook. & Arn. -- accepted -- Douglas' dustymaiden, Douglas dustymaiden, dusty maiden, dusty-maiden, Douglas' pincushion
  Chaenactis douglasii var. achilleifolia (Hook. & Arn.) A. Gray -- not accepted
  Chaenactis douglasii var. alpina A. Gray -- accepted -- alpine dustymaiden, alpine pincushion
  Chaenactis douglasii var. douglasii (Hook.) Hook. & Arn. -- accepted -- Douglas' dustymaiden, dusty-maiden
  Chaenactis douglasii var. glandulosa Cronquist -- not accepted
  Chaenactis douglasii var. montana M.E. Jones -- not accepted
  Chaenactis douglasii var. nana Stockw. -- not accepted
  Chaenactis douglasii var. rubricaulis (Rydb.) Ferris -- not accepted
  Chaenactis douglasii var. typicus Cronquist -- not accepted
  Chaenactis evermannii Greene -- accepted -- Evermann's pincushion
  Chaenactis fremontii A. Gray -- accepted -- pincushion flower, morningbride, Fremont's pincushion
  Chaenactis furcata Stockw. -- not accepted
  Chaenactis gillespiei Stockw. -- not accepted
  Chaenactis glabriuscula DC. -- accepted -- yellow pincushion
  Chaenactis glabriuscula var. aurea (Greene) Stockw. -- not accepted
  Chaenactis glabriuscula var. curta (A. Gray) Jeps. -- not accepted
  Chaenactis glabriuscula var. denudata (Nutt.) Munz -- not accepted
  Chaenactis glabriuscula var. glabriuscula DC. -- accepted -- yellow pincushion
  Chaenactis glabriuscula var. gracilenta (Greene) D.D. Keck -- not accepted
  Chaenactis glabriuscula var. heterocarpha (Torr. & A. Gray ex A. Gray) H.M. Hall -- accepted -- yellow pincushion
  Chaenactis glabriuscula var. lanosa (DC.) H.M. Hall -- accepted -- yellow pincushion
  Chaenactis glabriuscula var. megacephala A. Gray -- accepted -- yellow pincushion
  Chaenactis glabriuscula var. orcuttiana (Greene) H.M. Hall -- accepted -- Orcutt's yellow pincushion
  Chaenactis glabriuscula var. tenuifolia (Nutt.) H.M. Hall -- not accepted
  Chaenactis heterocarpha Torr. & A. Gray ex A. Gray -- not accepted
  Chaenactis humilis Rydb. -- not accepted
  Chaenactis lanosa DC. -- not accepted
  Chaenactis latifolia Stockw. -- not accepted
  Chaenactis leucopsis Greene -- not accepted -- alpine pincushion
  Chaenactis macrantha D.C. Eaton -- accepted -- bighead dustymaiden, large-flower pincushion, bighead pincushion
  Chaenactis mexicana Stockw. -- not accepted
  Chaenactis minuscula Greene -- not accepted
  Chaenactis nevadensis (Kellogg) A. Gray -- accepted -- Nevada dustymaiden, Nevada pincushion
  Chaenactis nevadensis var. mainsiana (A. Nelson & J.F. Macbr.) Stockw. -- not accepted
  Chaenactis nevii A. Gray -- accepted -- John Day's pincushion
  Chaenactis orcuttiana (Greene) Parish -- not accepted
  Chaenactis panamintensis Stockw. -- not accepted
  Chaenactis parishii A. Gray -- accepted -- Parish's chaenactis
  Chaenactis ramosa Stockw. -- not accepted
  Chaenactis rubricaulis Rydb. -- not accepted
  Chaenactis santolinoides Greene -- accepted -- Santolina pincushion
  Chaenactis santolinoides var. indurata Stockw. -- not accepted
  Chaenactis scaposa Eastw. -- not accepted
  Chaenactis stevioides Hook. & Arn. -- accepted -- Esteve's pincushion, Steve's dustymaiden, Steve's dusty maiden, Steve's pincushion
  Chaenactis stevioides var. brachypappa (A. Gray) H.M. Hall -- not accepted
  Chaenactis stevioides var. thornberi Stockw. -- not accepted
  Chaenactis suffrutescens A. Gray -- accepted -- Shasta chaenactis
  Chaenactis suffrutescens var. incana Stockw. -- not accepted
  Chaenactis suksdorfii Stockw. -- not accepted
  Chaenactis tanacetifolia A. Gray -- not accepted
  Chaenactis tanacetifolia var. gracilenta (Greene) Stockw. -- not accepted
  Chaenactis tenuifolia Nutt. -- not accepted
  Chaenactis tenuifolia var. orcuttiana Greene -- not accepted
  Chaenactis thompsonii Cronquist -- accepted -- Thompson's pincushion
  Chaenactis xantiana A. Gray -- accepted -- fleshcolor pincushion, flesh-color pincushion, Xantus pincushion
  Chaetadelpha A. Gray ex S. Watson -- accepted -- skeletonweed
  Chaetadelpha wheeleri A. Gray ex S. Watson -- accepted -- Wheeler's skeletonweed, Wheeler's chaetadelpha
  Chaetopappa DC. -- accepted -- leastdaisy, least daisy
  Chaetopappa alsinoides (Greene) D.D. Keck -- not accepted
  Chaetopappa asteroides Nutt. ex DC. -- accepted -- Arkansas leastdaisy, least daisy
  Chaetopappa asteroides var. asteroides Nutt. ex DC. -- accepted -- Arkansas leastdaisy
  Chaetopappa asteroides var. grandis Shinners -- accepted -- Arkansas leastdaisy
  Chaetopappa asteroides var. imberbis A. Gray -- not accepted
  Chaetopappa aurea (Nutt.) D.D. Keck -- not accepted
  Chaetopappa bellidiflora (Greene) D.D. Keck -- not accepted
  Chaetopappa bellidifolia (A. Gray & Engelm.) Shinners -- accepted -- whiteray leastdaisy
  Chaetopappa bellioides (A. Gray) Shinners -- accepted -- manyflower leastdaisy
  Chaetopappa bellioides var. hirticaulis Shinners -- not accepted
  Chaetopappa effusa (A. Gray) Shinners -- accepted -- spreading leastdaisy
  Chaetopappa elegans Soreng & Spellenb. -- not accepted
  Chaetopappa ericoides (Torr.) G.L. Nesom -- accepted -- rose heath, smallflower aster
  Chaetopappa exilis (A. Gray) D.D. Keck -- not accepted
  Chaetopappa fragilis (Brandegee) D.D. Keck -- not accepted
  Chaetopappa hersheyi S.F. Blake -- accepted -- Guadalupe leastdaisy
  Chaetopappa imberbis (A. Gray) G.L. Nesom -- accepted -- awnless leastdaisy
  Chaetopappa lyonii (A. Gray) D.D. Keck -- not accepted
  Chaetopappa parryi A. Gray -- accepted -- Parry's leastdaisy
  Chamaechaenactis Rydb. -- accepted -- chamaechaenactis
  Chamaechaenactis scaposa (Eastw.) Rydb. -- accepted -- fullstem
  Chamaechaenactis scaposa var. parva Preece & Turner -- not accepted -- fullstem
  Chamaechaenactis scaposa var. scaposa (Eastw.) Rydb. -- not accepted -- fullstem
  Chamaemelum Mill. -- accepted -- dogfennel
  Chamaemelum fuscatum (Brot.) Vasc. -- accepted -- dusky dogfennel
  Chamaemelum mixtum (L.) All. -- not accepted -- weedy dogfennel
  Chamaemelum nobile (L.) All. -- accepted -- Roman chamomile
  Chamomilla S.F. Gray -- not accepted -- chamomilla
  Chamomilla chamomilla (L.) Rydb. -- not accepted
  Chamomilla inodora (L.) Gilib. -- not accepted
  Chamomilla maritima (L.) Rydb. -- not accepted
  Chamomilla occidentalis (Greene) Rydb. -- not accepted
  Chamomilla recutita (L.) Rauschert -- not accepted
  Chamomilla suaveolens (Pursh) Rydb. -- not accepted
  Chaptalia Vent. -- accepted -- sunbonnets
  Chaptalia albicans (Sw.) Vent. ex Steud. -- accepted -- white sunbonnets
  Chaptalia alsophila Greene -- not accepted
  Chaptalia dentata (L.) Cass. -- accepted -- pineland daisy
  Chaptalia leucocephala Greene -- not accepted
  Chaptalia nutans (L.) Polak. -- accepted -- heal and draw
  Chaptalia nutans var. texana (Greene) Burkart -- not accepted
  Chaptalia seemannii (Sch. Bip.) Hemsl. -- not accepted
  Chaptalia texana Greene -- accepted -- silverpuff
  Chaptalia tomentosa Vent. -- accepted -- woolly sunbonnets
  Chloracantha G.L. Nesom -- accepted -- chloracantha
  Chloracantha spinosa (Benth.) G.L. Nesom -- accepted -- spiny chloracantha, spiny aster, devilweed aster, Mexican devilweed
  Chloracantha spinosa var. spinosa (Benth.) G.L. Nesom -- not accepted
  Chlorocrepis albiflora (Hook.) W.A. Weber -- not accepted
  Chlorocrepis fendleri (Sch. Bip.) W.A. Weber -- not accepted
  Chlorocrepis tristis (Willd. ex Spreng.) A. Löve & D. Löve -- not accepted
  Chlorocrepis tristis ssp. gracilis (Hook.) W.A. Weber -- not accepted
  Chondrilla L. -- accepted -- chondrilla
  Chondrilla juncea L. -- accepted -- rush skeletonweed, hogbite, skeletonweed
  Chondrophora nudata (Michx.) Britton -- not accepted
  Chondrophora virgata (Nutt.) Greene -- not accepted
  Chorisiva Rydb. -- accepted
  Chorisiva nevadensis (M.E. Jones) Rydb. -- accepted -- Nevada sumpweed
  Chromolaena DC. -- accepted -- thoroughwort
  Chromolaena bigelovii (A. Gray) R.M. King & H. Rob. -- accepted -- Bigelow's thoroughwort
  Chromolaena borinquensis (Britton) R.M. King & H. Rob. -- accepted -- limestone thoroughwort
  Chromolaena corymbosa (Aubl.) R.M. King & H. Rob. -- accepted -- Caribbean thoroughwort
  Chromolaena frustrata (B.L. Rob.) R.M. King & H. Rob. -- accepted -- Cape Sable thoroughwort
  Chromolaena geraniifolia (Urb.) R.M. King & H. Rob. -- accepted -- geraniumleaf thoroughwort
  Chromolaena ivifolia (L.) R.M. King & H. Rob. -- accepted -- ivyleaf thoroughwort
  Chromolaena odorata (L.) R.M. King & H. Rob. -- accepted -- Jack in the bush, Siamweed
  Chromolaena oteroi (Monach.) R.M. King & H. Rob. -- accepted -- Mona Island thoroughwort
  Chromolaena sinuata (Lam.) R.M. King & H. Rob. -- accepted -- wavyleaf thoroughwort
  Chrysactinia A. Gray -- accepted -- chrysactinia
  Chrysactinia mexicana A. Gray -- accepted -- damianita
  Chrysanthellum Rich. -- accepted
  Chrysanthellum americanum (L.) Vatke -- accepted
  Chrysanthemoides Fabr. -- accepted
  Chrysanthemoides monilifera (L.) Norlindh -- accepted
  Chrysanthemum L. -- accepted -- daisy
  Chrysanthemum arcticum L. -- accepted -- arctic daisy
  Chrysanthemum arcticum ssp. arcticum L. -- not accepted
  Chrysanthemum arcticum ssp. polare Hultén -- not accepted
  Chrysanthemum arcticum var. polare (Hultén) B. Boivin -- not accepted
  Chrysanthemum balsamita (L.) Baill. non L. -- not accepted
  Chrysanthemum balsamita var. tanacetoides Boiss. -- not accepted
  Chrysanthemum bipinnatum L. -- not accepted
  Chrysanthemum bipinnatum ssp. huronense (Nutt.) Hultén -- not accepted
  Chrysanthemum carinatum Schousb. -- not accepted -- tricolor daisy
  Chrysanthemum cinerariifolium (Trevir.) Vis. -- accepted -- pyrethrum
  Chrysanthemum coccineum Willd. -- not accepted -- pyrethrum daisy
  Chrysanthemum coronarium L. -- not accepted -- crowndaisy
  Chrysanthemum coronarium var. coronarium L. -- not accepted -- garland chrysanthemum
  Chrysanthemum coronarium var. spatiosum L.H. Bailey -- not accepted -- crowndaisy
  Chrysanthemum corymbosum L. -- not accepted
  Chrysanthemum frutescens L. -- not accepted -- marguerite
  Chrysanthemum indicum L. -- not accepted
  Chrysanthemum integrifolium Richardson -- not accepted
  Chrysanthemum lacustre Brot. -- not accepted
  Chrysanthemum leucanthemum L. -- not accepted -- ox-eye daisy, oxeye daisy
  Chrysanthemum leucanthemum var. boecheri B. Boivin -- not accepted
  Chrysanthemum leucanthemum var. pinnatifidum Lecoq & Lamotte -- not accepted -- ox-eye daisy, marguerite, oxeye daisy
  Chrysanthemum majus (Desf.) Asch. -- accepted -- daisy
  Chrysanthemum maximum Ramond -- not accepted
  Chrysanthemum morifolium Ramat. -- not accepted
  Chrysanthemum nipponicum (Franch. ex Maxim.) Spreng. -- not accepted
  Chrysanthemum parthenium (L.) Bernh. -- not accepted
  Chrysanthemum roseum Adams -- not accepted
  Chrysanthemum segetum L. -- not accepted -- corndaisy
  Chrysanthemum serotinum L. -- not accepted
  Chrysanthemum spatiosum (L.H. Bailey) L.H. Bailey -- not accepted
  Chrysanthemum uliginosum Pers. -- not accepted
  Chrysanthemum vulgare (L.) Bernh. -- not accepted
  Chrysanthemum X morifolium Ramat. (pro sp.) -- accepted -- florist's daisy, florist's chrysanthemum
  Chrysanthemum X superbum Bergmans ex J.W. Ingram -- not accepted
  Chrysocoma graminifolia L. -- not accepted
  Chrysocoma nudata Michx. -- not accepted
  Chrysogonum L. -- accepted -- chrysogonum
  Chrysogonum australe Alexander ex Small -- not accepted
  Chrysogonum virginianum L. -- accepted -- green and gold
  Chrysogonum virginianum var. australe (Alexander ex Small) H.E. Ahles -- accepted -- green and gold
  Chrysogonum virginianum var. brevistolon G.L. Nesom -- accepted
  Chrysogonum virginianum var. dentatum A. Gray -- not accepted
  Chrysogonum virginianum var. virginianum L. -- accepted -- green and gold
  Chrysoma Nutt. -- accepted -- chrysoma
  Chrysoma fasciculata Eastw. -- not accepted
  Chrysoma pauciflosculosa (Michx.) Greene -- accepted -- woody goldenrod
  Chrysoma solidaginoides Nutt. -- not accepted
  Chrysopsis (Nutt.) Elliot -- accepted -- goldenaster
  Chrysopsis adenolepis Fernald -- not accepted
  Chrysopsis alpicola Rydb. -- not accepted
  Chrysopsis alpicola var. glomerata A. Nelson -- not accepted
  Chrysopsis alpina Nutt. -- not accepted
  Chrysopsis amplifolia Rydb. -- not accepted
  Chrysopsis angustifolia Rydb. -- not accepted
  Chrysopsis arenicola Alexander ex Small -- not accepted
  Chrysopsis arida A. Nelson -- not accepted
  Chrysopsis aspera Shuttlw. ex Small -- not accepted
  Chrysopsis bakeri Greene -- not accepted
  Chrysopsis ballardii Rydb. -- not accepted
  Chrysopsis barbata Rydb. -- not accepted
  Chrysopsis berlandieri Greene -- not accepted
  Chrysopsis bolanderi A. Gray -- not accepted
  Chrysopsis breweri A. Gray -- not accepted
  Chrysopsis breweri var. multibracteata Jeps. -- not accepted
  Chrysopsis butleri Rydb. -- not accepted
  Chrysopsis californica Elmer -- not accepted
  Chrysopsis camphorata Eastw. -- not accepted
  Chrysopsis camporum Greene -- not accepted
  Chrysopsis camporum var. glandulissimum (Semple) Cronquist -- not accepted
  Chrysopsis canescens (DC.) Torr. & A. Gray non DC. -- not accepted
  Chrysopsis canescens var. nana A. Gray -- not accepted
  Chrysopsis caudata Rydb. -- not accepted
  Chrysopsis columbiana Greene -- not accepted
  Chrysopsis cooperi A. Nelson -- not accepted
  Chrysopsis cruiseana Dress -- not accepted
  Chrysopsis cryptocephala Woot. & Standl. -- not accepted
  Chrysopsis decumbens Chapm. -- not accepted
  Chrysopsis depressa Rydb. -- not accepted
  Chrysopsis echioides Benth. -- not accepted
  Chrysopsis falcata (Pursh) Elliot -- not accepted
  Chrysopsis fastigiata Greene -- not accepted
  Chrysopsis flexuosa Nash -- not accepted
  Chrysopsis floridana Small -- accepted -- Florida goldenaster, Florida golden aster
  Chrysopsis foliosa Nutt. -- not accepted
  Chrysopsis fulcrata Greene -- not accepted
  Chrysopsis gigantea Small -- not accepted
  Chrysopsis godfreyi Semple -- accepted -- Godfrey's goldenaster
  Chrysopsis gossypina (Michx.) Elliot -- accepted -- cottony goldenaster
  Chrysopsis gossypina ssp. cruiseana (Dress) Semple -- accepted -- cottony goldenaster
  Chrysopsis gossypina ssp. gossypina (Michx.) Elliot -- accepted -- cottony goldenaster
  Chrysopsis gossypina ssp. hyssopifolia (Nutt.) Semple -- accepted -- cottony goldenaster
  Chrysopsis gracilis Eastw. -- not accepted
  Chrysopsis graminifolia (Michx.) Elliot -- not accepted
  Chrysopsis graminifolia var. aspera (Shuttlew. ex Small) A. Gray -- not accepted
  Chrysopsis graminifolia var. latifolia Fernald -- not accepted
  Chrysopsis graminifolia var. microcephala (Small) Cronquist -- not accepted
  Chrysopsis hirsutissima Greene -- not accepted
  Chrysopsis hispida (Hook.) DC. -- not accepted
  Chrysopsis hispida var. stenophylla A. Gray -- not accepted
  Chrysopsis horrida Rydb. -- not accepted
  Chrysopsis hyssopifolia Nutt. -- not accepted
  Chrysopsis imbricata A. Nelson -- not accepted
  Chrysopsis jonesii S.F. Blake -- not accepted
  Chrysopsis lanuginosa Small -- accepted -- Lynn Haven goldenaster
  Chrysopsis latisquamea Pollard -- accepted -- pineland goldenaster
  Chrysopsis linearifolia Semple -- accepted -- narrowleaf goldenaster
  Chrysopsis linearifolia ssp. dressii Semple -- accepted -- Dress' goldenaster
  Chrysopsis linearifolia ssp. linearifolia Semple -- accepted -- narrowleaf goldenaster
  Chrysopsis longii Fernald -- not accepted
  Chrysopsis mariana (L.) Elliot -- accepted -- Maryland goldenaster
  Chrysopsis mariana var. floridana (Small) Fernald -- not accepted
  Chrysopsis mariana var. macradenia Fernald -- not accepted
  Chrysopsis microcephala Small -- not accepted
  Chrysopsis mixta Dress -- not accepted
  Chrysopsis mollis Nutt. -- not accepted
  Chrysopsis nervosa (Willd.) Fernald -- not accepted
  Chrysopsis nitidula Woot. & Standl. -- not accepted
  Chrysopsis nuttallii Britton -- not accepted
  Chrysopsis oligantha Chapm. ex Torr. & A. Gray -- not accepted
  Chrysopsis oregona (Nutt.) A. Gray -- not accepted
  Chrysopsis oregona var. compacta D.D. Keck -- not accepted
  Chrysopsis oregona var. rudis (Greene) Jeps. -- not accepted
  Chrysopsis oregona var. scaberrima A. Gray -- not accepted
  Chrysopsis pedunculata Greene -- not accepted
  Chrysopsis pilosa Nutt. -- not accepted -- soft goldenaster, soft goldaster
  Chrysopsis pilosa (Walter) Britton non Nutt. -- not accepted -- soft goldenaster
  Chrysopsis pinifolia Elliot -- not accepted
  Chrysopsis pumila Greene -- not accepted
  Chrysopsis resinolens A. Nelson -- not accepted
  Chrysopsis ruthii Small -- not accepted
  Chrysopsis rutteri (Rothr.) Greene -- not accepted
  Chrysopsis scabra (Pursh) Elliot -- not accepted
  Chrysopsis scabrella Torr. & A. Gray -- accepted -- coastal plain goldenaster, coastalplain goldenaster
  Chrysopsis scabrifolia A. Nelson -- not accepted
  Chrysopsis senilis Woot. & Standl. -- not accepted
  Chrysopsis sessiliflora Nutt. -- not accepted
  Chrysopsis sessiliflora var. bolanderi (A. Gray) A. Gray -- not accepted
  Chrysopsis shastensis Jeps. -- not accepted
  Chrysopsis stenophylla (A. Gray) Greene -- not accepted
  Chrysopsis subulata Small -- accepted -- scrubland goldenaster
  Chrysopsis texana G.L. Nesom -- not accepted -- Texas chrysopsis
  Chrysopsis tracyi Small -- not accepted
  Chrysopsis trichophylla (Nutt.) Elliot -- not accepted
  Chrysopsis villosa (Pursh) Nutt. ex DC. -- not accepted
  Chrysopsis villosa var. angustifolia (Rydb.) Cronquist -- not accepted
  Chrysopsis villosa var. bolanderi (A. Gray) A. Gray ex Jeps. -- not accepted
  Chrysopsis villosa var. camphorata (Eastw.) Jeps. -- not accepted
  Chrysopsis villosa var. camporum (Greene) Cronquist -- not accepted
  Chrysopsis villosa var. canescens (DC.) A. Gray -- not accepted
  Chrysopsis villosa var. echioides (Benth.) A. Gray -- not accepted
  Chrysopsis villosa var. fastigiata (Greene) H.M. Hall -- not accepted
  Chrysopsis villosa var. foliosa (Nutt.) D.C. Eaton -- not accepted
  Chrysopsis villosa var. glomerata (A. Nelson) V.L. Harms -- not accepted
  Chrysopsis villosa var. hispida (Hook.) A. Gray -- not accepted
  Chrysopsis villosa var. sessiliflora (Nutt.) A. Gray -- not accepted
  Chrysopsis villosa var. stenophylla (A. Gray) A. Gray -- not accepted
  Chrysopsis villosa var. viscida A. Gray -- not accepted
  Chrysopsis viscida (A. Gray) Greene -- not accepted
  Chrysopsis viscida ssp. cinerascens S.F. Blake -- not accepted
  Chrysopsis wisconsinensis Shinners -- not accepted
  Chrysopsis wrightii A. Gray -- not accepted
  Chrysothamnus Nutt. -- accepted -- rabbitbrush
  Chrysothamnus albidus (M.E. Jones ex A. Gray) Greene -- not accepted -- whiteflower rabbitbrush, alkali rabbitbrush
  Chrysothamnus axillaris D.D. Keck -- not accepted
  Chrysothamnus baileyi Woot. & Standl. -- not accepted -- Bailey's rabbitbrush
  Chrysothamnus bolanderi (A. Gray) Greene -- not accepted
  Chrysothamnus depressus Nutt. -- accepted -- longflower rabbitbrush, dwarf rabbitbrush
  Chrysothamnus eremobius L.C. Anderson -- accepted -- pintwater rabbitbrush
  Chrysothamnus frigidus Greene -- not accepted
  Chrysothamnus gramineus H.M. Hall -- not accepted -- Panamint rock goldenrod, Charleston rabbitbrush
  Chrysothamnus graveolens (Nutt.) Greene -- not accepted
  Chrysothamnus greenei (A. Gray) Greene -- accepted -- Greene's rabbitbrush
  Chrysothamnus greenei ssp. filifolius (Rydb.) H.M. Hall & Clem. -- not accepted
  Chrysothamnus greenei var. filifolius (Rydb.) S.F. Blake -- not accepted
  Chrysothamnus howardii (Parry ex A. Gray) Greene -- not accepted
  Chrysothamnus humilis Greene -- accepted -- Truckee rabbitbrush, low rabbitbrush
  Chrysothamnus linifolius Greene -- not accepted -- spearleaf rabbitbrush, spear-leaf rabbitbrush
  Chrysothamnus molestus (S.F. Blake) L.C. Anderson -- accepted -- Arizona rabbitbrush, stickyfruit low rabbitbrush
  Chrysothamnus nauseosus (Pall. ex Pursh) Britton -- not accepted -- gray rabbitbrush
  Chrysothamnus nauseosus ssp. albicaulis (Nutt.) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. arenarius L.C. Anderson -- not accepted
  Chrysothamnus nauseosus ssp. bernardinus (H.M. Hall) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. bigelovii (A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. bolanderi (A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. ceruminosus (Durand & Hilg.) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. consimilis (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. gnaphalodes (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. graveolens (Nutt.) Piper -- not accepted
  Chrysothamnus nauseosus ssp. hololeucus (A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. iridis L.C. Anderson -- not accepted
  Chrysothamnus nauseosus ssp. junceus (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. latisquameus (A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. leiospermus (A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. mohavensis (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. nanus (Cronquist) D.D. Keck -- not accepted
  Chrysothamnus nauseosus ssp. nauseosus (Pall. ex Pursh) Britton -- not accepted -- rubber rabbitbrush
  Chrysothamnus nauseosus ssp. nitidus L.C. Anderson -- not accepted
  Chrysothamnus nauseosus ssp. pinifolius (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. psilocarpus (S.F. Blake) L.C. Anderson -- not accepted
  Chrysothamnus nauseosus ssp. salicifolius (Rydb.) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. speciosus (Nutt.) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. texensis L.C. Anderson -- not accepted
  Chrysothamnus nauseosus ssp. turbinatus (M.E. Jones) H.M. Hall & Clem. -- not accepted
  Chrysothamnus nauseosus ssp. uintahensis L.C. Anderson -- not accepted
  Chrysothamnus nauseosus ssp. viscosus D.D. Keck -- not accepted
  Chrysothamnus nauseosus ssp. washoensis L.C. Anderson -- not accepted
  Chrysothamnus nauseosus var. abbreviatus (M.E. Jones) S.F. Blake -- not accepted
  Chrysothamnus nauseosus var. albicaulis (Nutt.) Rydb. -- not accepted
  Chrysothamnus nauseosus var. arenarius (L.C. Anderson) S.L. Welsh -- not accepted
  Chrysothamnus nauseosus var. artus (A. Nelson) Cronquist -- not accepted
  Chrysothamnus nauseosus var. bigelovii (A. Gray) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. consimilis (Greene) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. glabratus (A. Gray) Cronquist -- not accepted
  Chrysothamnus nauseosus var. glareosus (M.E. Jones) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. gnaphalodes (Greene) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. graveolens (Nutt.) Piper ex H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. hololeucus (A. Gray) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. iridis (L.C. Anderson) S.L. Welsh -- not accepted
  Chrysothamnus nauseosus var. junceus (Greene) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. latisquameus (A. Gray) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. leiospermus (A. Gray) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. mohavensis (Greene) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. nanus Cronquist -- not accepted
  Chrysothamnus nauseosus var. nauseosus (Pall. ex Pursh) Britton -- not accepted
  Chrysothamnus nauseosus var. nitidus (L.C. Anderson) S.L. Welsh -- not accepted
  Chrysothamnus nauseosus var. oreophilus (A. Nelson) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. petrophilus Cronquist -- not accepted
  Chrysothamnus nauseosus var. psilocarpus S.F. Blake -- not accepted
  Chrysothamnus nauseosus var. salicifolius (Rydb.) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. speciosus (Nutt.) H.M. Hall -- not accepted
  Chrysothamnus nauseosus var. turbinatus (M.E. Jones) S.F. Blake -- not accepted
  Chrysothamnus nauseosus var. typicus (H.M. Hall) Cronquist -- not accepted
  Chrysothamnus nauseosus var. uintahensis (L.C. Anderson) S.L. Welsh -- not accepted
  Chrysothamnus nauseosus var. washoensis (L.C. Anderson) Cronquist -- not accepted
  Chrysothamnus paniculatus (A. Gray) H.M. Hall -- not accepted
  Chrysothamnus parryi (A. Gray) Greene -- not accepted
  Chrysothamnus parryi ssp. affinis (A. Nelson) L.C. Anderson -- not accepted
  Chrysothamnus parryi ssp. asper (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. attenuatus (M.E. Jones) H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. howardii (Parry ex A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. imulus H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. latior H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. monocephalus (A. Nelson & Kennedy) H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. montanus L.C. Anderson -- not accepted
  Chrysothamnus parryi ssp. nevadensis (A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. parryi (A. Gray) Greene -- not accepted -- Parry's rabbitbrush
  Chrysothamnus parryi ssp. salmonensis L.C. Anderson -- not accepted
  Chrysothamnus parryi ssp. typicus H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi ssp. vulcanicus (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus parryi var. affinis (A. Nelson) Cronquist -- not accepted
  Chrysothamnus parryi var. asper (Greene) Munz -- not accepted
  Chrysothamnus parryi var. attenuatus (M.E. Jones) Kittell -- not accepted
  Chrysothamnus parryi var. howardii (Parry ex A. Gray) Kittell -- not accepted
  Chrysothamnus parryi var. monocephalus (A. Nelson & Kennedy) Jeps. -- not accepted
  Chrysothamnus parryi var. nevadensis (A. Gray) Kittell -- not accepted
  Chrysothamnus parryi var. vulcanicus (Greene) Jeps. -- not accepted
  Chrysothamnus pulchellus (A. Gray) Greene -- not accepted -- southwestern rabbitbrush, southwest rabbitbrush
  Chrysothamnus pulchellus ssp. baileyi (Woot. & Standl.) H.M. Hall & Clem. -- not accepted -- Bailey's rabbitbrush
  Chrysothamnus pulchellus ssp. elatior (Standl.) H.M. Hall & Clem. -- not accepted
  Chrysothamnus pulchellus ssp. pulchellus (Gray) Greene -- not accepted -- southwestern rabbitbrush
  Chrysothamnus pulchellus var. baileyi (Woot. & Standl.) S.F. Blake -- not accepted
  Chrysothamnus scopulorum (M.E. Jones) Urbatsch, R.P. Roberts & Neubig -- accepted -- Grand Canyon glowweed
  Chrysothamnus spathulatus L.C. Anderson -- not accepted -- Guadalupe rabbitbrush
  Chrysothamnus stylosus (Eastw.) Urbatsch -- accepted -- pillar false gumweed
  Chrysothamnus teretifolius (Durand & Hilg.) H.M. Hall -- not accepted
  Chrysothamnus vaseyi (A. Gray) Greene -- accepted -- Vasey's rabbitbrush
  Chrysothamnus viscidiflorus (Hook.) Nutt. -- accepted -- yellow rabbitbrush, Douglas rabbitbrush, green rabbitbrush, Douglas' rabbitbrush
  Chrysothamnus viscidiflorus ssp. axillaris (D.D. Keck) L.C. Anderson -- accepted -- yellow rabbitbrush, low rabbitbrush, Douglas' rabbitbrush
  Chrysothamnus viscidiflorus ssp. elegans (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus viscidiflorus ssp. humilis (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus viscidiflorus ssp. lanceolatus (Nutt.) H.M. Hall & Clem. -- accepted -- yellow rabbitbrush, lanceleaf low rabbitbrush, lanceleaf rabbitbrush
  Chrysothamnus viscidiflorus ssp. latifolius (D.C. Eaton) H.M. Hall & Clem. -- not accepted
  Chrysothamnus viscidiflorus ssp. linifolius (Greene) H.M. Hall & Clem. -- not accepted
  Chrysothamnus viscidiflorus ssp. planifolius L.C. Anderson -- accepted -- yellow rabbitbrush, flatleaf low rabbitbrush
  Chrysothamnus viscidiflorus ssp. puberulus (D.C. Eaton) H.M. Hall & Clem. -- accepted -- yellow rabbitbrush, hairy low rabbitbrush, downy rabbitbrush
  Chrysothamnus viscidiflorus ssp. pumilus (Nutt.) H.M. Hall & Clem. -- not accepted
  Chrysothamnus viscidiflorus ssp. stenophyllus (A. Gray) H.M. Hall & Clem. -- not accepted
  Chrysothamnus viscidiflorus ssp. typicus H.M. Hall & Clem. -- not accepted
  Chrysothamnus viscidiflorus ssp. viscidiflorus (Hook.) Nutt. -- accepted -- yellow rabbitbrush, green rabbitbrush, Douglas' rabbitbrush
  Chrysothamnus viscidiflorus ssp. viscidiflorus var. latifolius (D.C. Eaton) Greene -- not accepted
  Chrysothamnus viscidiflorus ssp. viscidiflorus var. stenophyllus (A. Gray) H.M. Hall -- not accepted -- yellow rabbitbrush, small rabbitbrush
  Chrysothamnus viscidiflorus var. elegans (Greene) S.F. Blake -- not accepted
  Chrysothamnus viscidiflorus var. humilis (Greene) Jeps. -- not accepted
  Chrysothamnus viscidiflorus var. lanceolatus (Nutt.) Greene -- not accepted
  Chrysothamnus viscidiflorus var. latifolius (D.C. Eat.) Greene -- not accepted -- yellow rabbitbrush
  Chrysothamnus viscidiflorus var. linifolius (Greene) Kittell -- not accepted
  Chrysothamnus viscidiflorus var. ludens Shinners -- not accepted
  Chrysothamnus viscidiflorus var. molestus S.F. Blake -- not accepted
  Chrysothamnus viscidiflorus var. puberulus (D.C. Eaton) Jeps. -- not accepted
  Chrysothamnus viscidiflorus var. pumilus (Nutt.) Jeps. -- not accepted
  Chrysothamnus viscidiflorus var. typicus (H.M. Hall & Clem.) Cronquist -- not accepted
  Chrysothamnus viscidiflorus var. viscidiflorus (Hook.) Nutt. -- not accepted -- yellow rabbitbrush
  Chthonia glaucescens Cass. -- not accepted
  Cichorium L. -- accepted -- chicory, chickory
  Cichorium endivia L. -- accepted -- cultivated endive
  Cichorium intybus L. -- accepted -- chicory, French endive, succory, chickory, blue sailors, coffeeweed, common chicory
  Cichorium intybus var. foliosum Hegi -- not accepted
  Cichorium intybus var. sativum (Bisch.) Janch. -- not accepted
  Cineraria L. -- accepted -- cineraria
  Cineraria congesta R. Br. -- not accepted
  Cineraria multiflora L'Hér. -- accepted
  Cineraria salicifolia Kunth -- not accepted
  Cineraria saxifraga DC. -- accepted -- wild cineraria
  Cirsium Mill. -- accepted -- thistle
  Cirsium acanthodontum S.F. Blake -- not accepted
  Cirsium acaule var. americanum A. Gray -- not accepted
  Cirsium acaulescens (Rydb.) K. Schum. -- not accepted
  Cirsium acuatum (Osterh.) Petr. -- not accepted
  Cirsium altissimum (L.) Hill -- accepted -- tall thistle, roadside thistle
  Cirsium altissimum var. biltmoreanum Petr. -- not accepted
  Cirsium altissimum var. filipendulum (Engelm.) A. Gray -- not accepted
  Cirsium amblylepis Petr. -- not accepted -- Mt. Tamalpais thistle
  Cirsium americanum (A. Gray) K. Schum. -- not accepted
  Cirsium andersonii (A. Gray) Petr. -- accepted -- rose thistle, Anderson's thistle
  Cirsium andrewsii (A. Gray) Jeps. -- accepted -- Franciscan thistle
  Cirsium araneans Rydb. -- not accepted -- jeweled thistle
  Cirsium arcuum A. Nelson -- not accepted -- powderpuff thistle
  Cirsium aridum Dorn -- not accepted -- desert thistle
  Cirsium arizonicum (A. Gray) Petr. -- accepted -- Arizona thistle
  Cirsium arizonicum var. arizonicum (A. Gray) Petr. -- accepted -- Arizona thistle
  Cirsium arizonicum var. bipinnatum (Eastw.) D.J. Keil -- accepted -- Cainville thistle
  Cirsium arizonicum var. chellyense (R.J. Moore & Frankton) D.J. Keil -- accepted -- Navajo thistle, queen thistle, monarch thistle
  Cirsium arizonicum var. nidulum (M.E. Jones) S.L. Welsh -- not accepted -- Arizona thistle
  Cirsium arizonicum var. rothrockii (A. Gray) D.J. Keil -- accepted -- Rothrock's thistle
  Cirsium arizonicum var. tenuisectum D.J. Keil -- accepted -- desert mountains thistle
  Cirsium arvense (L.) Scop. -- accepted -- Canada thistle, Canadian thistle, Californian thistle, creeping thistle, field thistle
  Cirsium arvense var. argenteum (Vest) Fiori -- not accepted
  Cirsium arvense var. horridum Wimm. & Grab. -- not accepted
  Cirsium arvense var. integrifolium Wimm. & Grab. -- not accepted
  Cirsium arvense var. mite Wimm. & Grab. -- not accepted
  Cirsium arvense var. vestitum Wimm. & Grab. -- not accepted
  Cirsium barnebyi S.L. Welsh & Neese -- accepted -- Barneby's thistle
  Cirsium bigelovii DC. -- not accepted
  Cirsium bipinnatum (Eastw.) Rydb. -- not accepted
  Cirsium blumeri Petr. -- not accepted
  Cirsium botrys Petr. -- not accepted
  Cirsium brevifolium Nutt. -- accepted -- Palouse thistle
  Cirsium brevistylum Cronquist -- accepted -- clustered thistle
  Cirsium breweri (A. Gray) Jeps. -- not accepted
  Cirsium breweri var. lanosissimum Petr. -- not accepted
  Cirsium breweri var. wrangelii Petr. -- not accepted
  Cirsium butleri (Rydb.) Petr. -- not accepted
  Cirsium calcareum (M.E. Jones) Woot. & Standl. -- not accepted -- Cainville thistle
  Cirsium calcareum var. bipinnatum (Eastw.) S.L. Welsh -- not accepted
  Cirsium calcareum var. pulchellum (Greene) S.L. Welsh -- not accepted
  Cirsium californicum A. Gray -- not accepted
  Cirsium californicum ssp. pseudoreglense Petr. -- not accepted
  Cirsium californicum var. bernardinum (Greene) Petr. -- not accepted
  Cirsium californicum var. californicum A. Gray -- not accepted -- California thistle
  Cirsium callilepis (Greene) Jeps. -- not accepted
  Cirsium callilepis var. callilepis (Greene) Jeps. -- not accepted -- fringebract thistle
  Cirsium callilepis var. oregonense (Petr.) J.T. Howell -- not accepted
  Cirsium callilepis var. pseudocarlinoides (Petr.) J.T. Howell -- not accepted
  Cirsium campylon H.K. Sharsmith -- not accepted
  Cirsium candidissimum (Greene) Davidson & Moxley -- not accepted
  Cirsium canescens Nutt. -- accepted -- prairie thistle, Platte thistle
  Cirsium canovirens (Rydb.) Petr. -- not accepted -- graygreen thistle
  Cirsium canum (L.) All. -- accepted -- Queen Anne's thistle
  Cirsium carolinianum (Walter) Fernald & B.G. Schub. -- accepted -- soft thistle, Carolina thistle
  Cirsium centaureae (Rydb.) K. Schum. -- not accepted
  Cirsium chellyense J.W. Moore & Frankton -- not accepted -- queen thistle
  Cirsium chuskaense J.W. Moore & Frankton -- not accepted -- monarch thistle
  Cirsium ciliolatum (L.F. Hend.) J.T. Howell -- accepted -- Ashland thistle
  Cirsium clavatum (M.E. Jones) Petr. -- accepted -- Fish Lake thistle
  Cirsium clavatum var. americanum (A. Gray) D.J. Keil -- accepted -- Rocky Mountain fringed thistle, fringed thistle, lacy thistle, mountain slope thistle, porcupine thistle, crow thistle, gray thistle
  Cirsium clavatum var. clavatum (M.E. Jones) Petr. -- accepted -- Fish Lake thistle
  Cirsium clavatum var. osterhoutii (Rydb.) D.J. Keil -- accepted -- Osterhout's thistle, jeweled thistle
  Cirsium clokeyi S.F. Blake -- not accepted -- whitespine thistle, Charleston Mountain thistle
  Cirsium coccinatum Osterh. -- not accepted
  Cirsium coloradense (Rydb.) Cockerell -- not accepted
  Cirsium coloradense ssp. acaulescens (Rydb.) Petr. -- not accepted
  Cirsium coloradense ssp. longissimum (A. Heller) Petr. -- not accepted
  Cirsium congdonii J.W. Moore & Frankton -- not accepted -- rosette thistle
  Cirsium coulteri Harv. & A. Gray -- not accepted
  Cirsium crassicaule (Greene) Jeps. -- accepted -- slough thistle
  Cirsium cymosum (Greene) J.T. Howell -- accepted -- peregrine thistle
  Cirsium cymosum var. canovirens (Rydb.) D.J. Keil -- accepted -- graygreen thistle
  Cirsium cymosum var. cymosum (Greene) J.T. Howell -- accepted -- peregrine thistle
  Cirsium davisii Cronquist -- not accepted
  Cirsium diffusum (Eastw.) Rydb. -- not accepted
  Cirsium discolor (Muhl. ex Willd.) Spreng. -- accepted -- field thistle
  Cirsium douglasii DC. -- accepted -- Douglas' thistle
  Cirsium douglasii var. breweri (A. Gray) D.J. Keil & C.E. Turner -- accepted -- Douglas' thistle
  Cirsium douglasii var. canescens (Petr.) J.T. Howell -- not accepted
  Cirsium douglasii var. douglasii DC. -- accepted -- Douglas' thistle
  Cirsium drummondii Torr. & A. Gray -- accepted -- dwarf thistle
  Cirsium drummondii ssp. lanatum Petr. -- not accepted
  Cirsium drummondii ssp. latisquamum Petr. -- not accepted
  Cirsium drummondii ssp. vexans Petr. -- not accepted
  Cirsium drummondii var. acaulescens (Rydb.) J.F. Macbr. -- not accepted
  Cirsium drummondii var. oregonense Petr. -- not accepted
  Cirsium eatonii (A. Gray) B.L. Rob. -- accepted -- Eaton's thistle, mountaintop thistle
  Cirsium eatonii var. clokeyi (S.F. Blake) D.J. Keil -- accepted -- Clokey's thistle, Spring Mountains thistle, white-spine thistle
  Cirsium eatonii var. eatonii (A. Gray) B.L. Rob. -- accepted -- Eaton's thistle, mountaintop thistle
  Cirsium eatonii var. eriocephalum (A. Gray) D.J. Keil -- accepted -- mountain thistle, alpine thistle
  Cirsium eatonii var. harrisonii S.L. Welsh -- not accepted
  Cirsium eatonii var. hesperium (Eastw.) D.J. Keil -- accepted -- tall mountain thistle
  Cirsium eatonii var. murdockii S.L. Welsh -- accepted -- northern mountain thistle, Murdock's thistle
  Cirsium eatonii var. peckii (L.F. Hend.) D.J. Keil -- accepted -- Steens Mountain thistle, ghost thistle
  Cirsium eatonii var. viperinum D.J. Keil -- accepted -- Snake Range thistle
  Cirsium edule Nutt. -- accepted -- edible thistle, Hall's thistle, cardoon
  Cirsium edule var. edule Nutt. -- accepted -- edible thistle, Hall's thistle
  Cirsium edule var. macounii (Greene) D.J. Keil -- accepted -- Macoun's thistle
  Cirsium edule var. wenatchense D.J. Keil -- accepted -- Wenatchee thistle
  Cirsium engelmannii Rydb. -- accepted -- Engelmann's thistle
  Cirsium eriocephalum A. Gray -- not accepted
  Cirsium eriocephalum var. leiocephalum D.C. Eaton -- not accepted
  Cirsium erosum (Rydb.) K. Schum. -- not accepted
  Cirsium filipendulum Engelm. -- not accepted
  Cirsium flaccidum Small -- not accepted
  Cirsium floccosum (Rydb.) Petr. -- not accepted
  Cirsium flodmanii (Rydb.) Arthur -- accepted -- Flodman's thistle
  Cirsium foliosum (Hook.) DC. -- accepted -- elk thistle, Drummond's thistle, leafy thistle, meadow thistle
  Cirsium foliosum var. minganense (Victorin) B. Boivin -- not accepted -- chardon multifeuille variété de la Minganie
  Cirsium fontinale (Greene) Jeps. -- accepted -- fountain thistle
  Cirsium fontinale var. campylon (H. Sharsm.) Pilz ex Keil & C. Turner -- accepted -- Mt. Hamilton thistle
  Cirsium fontinale var. fontinale (Greene) Jeps. -- accepted -- fountain thistle
  Cirsium fontinale var. obispoense J.T. Howell -- accepted -- Chorro Creek bog thistle
  Cirsium gilense Woot. & Standl. -- not accepted -- Gila thistle
  Cirsium grahamii A. Gray -- accepted -- Graham's thistle
  Cirsium griseum (Rydb.) K. Schum. -- not accepted -- gray thistle
  Cirsium hallii (A. Gray) M.E. Jones -- not accepted -- Hall's thistle
  Cirsium helenioides (L.) Hill -- accepted -- melancholy thistle
  Cirsium helleri (Small) Cory -- not accepted
  Cirsium hesperium (Eastw.) Petr. -- not accepted
  Cirsium heterophyllum (L.) Hill -- not accepted
  Cirsium hillii (Canby) Fernald -- not accepted -- Hill's thistle
  Cirsium hookerianum Nutt. -- accepted -- white thistle
  Cirsium hookerianum var. eriocephalum (A. Gray) A. Nelson -- not accepted
  Cirsium horridulum Michx. -- accepted -- yellow thistle
  Cirsium horridulum var. elliottii Torr. & A. Gray -- not accepted
  Cirsium horridulum var. horridulum Michx. -- accepted -- yellow thistle
  Cirsium horridulum var. megacanthum (Nutt.) D.J. Keil -- accepted
  Cirsium horridulum var. vittatum (Small) R.W. Long -- accepted -- yellow thistle
  Cirsium howellii Petr. -- not accepted
  Cirsium humboldtense Rydb. -- not accepted -- Humboldt County thistle
  Cirsium hydrophilum (Greene) Jeps. -- accepted -- Suisun thistle
  Cirsium hydrophilum var. hydrophilum (Greene) Jeps. -- accepted -- Suisun thistle
  Cirsium hydrophilum var. vaseyi (A. Gray) J.T. Howell -- accepted -- Vasey's thistle
  Cirsium inamoenum (Greene) D.J. Keil -- accepted
  Cirsium inamoenum var. davisii (Cronquist) D.J. Keil -- accepted -- Davis' thistle
  Cirsium inamoenum var. inamoenum (Greene) D.J. Keil -- accepted -- Greene's thistle, Jackson Hole thistle
  Cirsium incanum (S.G. Gmel.) Fisch. ex M. Bieb. -- not accepted
  Cirsium inornatum Woot. & Standl. -- not accepted -- Cloudcroft thistle
  Cirsium japonicum Fisch. ex DC. -- accepted -- Japanese thistle
  Cirsium joanne S.L. Welsh, N.D. Atwood & L.C. Higgins -- accepted -- Joanna's thistle
  Cirsium kamtschaticum Ledeb. ex DC. -- accepted -- Kamchatka thistle
  Cirsium kelseyi (Rydb.) Petr. -- not accepted
  Cirsium lacerum (Rydb.) Petr. -- not accepted
  Cirsium lactucinum Rydb. -- not accepted
  Cirsium lanceolatum (L.) Scop., non Hill -- not accepted -- bull thistle
  Cirsium lanceolatum var. hypoleucum DC. -- not accepted
  Cirsium laterifolium (Osterh.) Petr. -- not accepted -- porcupine thistle
  Cirsium lecontei Torr. & A. Gray -- accepted -- Le Conte's thistle
  Cirsium loncholepis Petr. -- not accepted -- La Graciosa thistle
  Cirsium longistylum J.W. Moore & Frankton -- accepted -- longstyle thistle
  Cirsium macounii (Greene) Rydb. -- not accepted
  Cirsium magnificum (A. Nelson) Petr. -- not accepted
  Cirsium maritimum (Elmer) Petr. -- not accepted
  Cirsium megacephalum (A. Gray) Cockerell -- not accepted
  Cirsium mendocinum Petr. -- not accepted -- Mendocino thistle
  Cirsium mexicanum DC. -- accepted -- Mexican thistle
  Cirsium minganense Victorin -- not accepted
  Cirsium modestum (Osterh.) Cockerell -- not accepted -- lacy thistle
  Cirsium mohavense (Greene) Petr. -- accepted -- Mojave thistle, virgin thistle, Rusby's thistle
  Cirsium montigenum Petr. -- not accepted
  Cirsium murdockii (S.L. Welsh) Cronquist -- not accepted -- Murdock's thistle
  Cirsium muticum Michx. -- accepted -- swamp thistle
  Cirsium muticum var. monticola Fernald -- not accepted
  Cirsium muticum var. subpinnatifidum (Britton) Fernald -- not accepted
  Cirsium navajoense J.W. Moore & Frankton -- not accepted -- Navajo thistle
  Cirsium nebraskense (Britton) Lunell -- not accepted
  Cirsium nebraskense var. discissum Lunell -- not accepted
  Cirsium nelsonii (Pammel) Petr. -- not accepted
  Cirsium neomexicanum A. Gray -- accepted -- New Mexico thistle, powderpuff thistle, Utah thistle, lavender thistle
  Cirsium neomexicanum var. neomexicanum A. Gray -- not accepted -- New Mexico thistle
  Cirsium neomexicanum var. utahense (Petr.) S.L. Welsh -- not accepted -- Utah thistle
  Cirsium nidulum (M.E. Jones) Petr. -- not accepted
  Cirsium nuttallii DC. -- accepted -- Nuttall's thistle
  Cirsium oblanceolatum (Rydb.) K. Schum. -- not accepted
  Cirsium occidentale (Nutt.) Jeps. -- accepted -- cobwebby thistle
  Cirsium occidentale var. californicum (A. Gray) Keil & C. Turner -- accepted -- cobwebby thistle
  Cirsium occidentale var. candidissimum (Greene) J.F. Macbr. -- accepted -- snowy thistle
  Cirsium occidentale var. compactum Hoover -- accepted -- compact cobwebby thistle
  Cirsium occidentale var. coulteri (Harv. & A. Gray) Jeps. -- accepted -- Coulter's thistle
  Cirsium occidentale var. lucianum D.J. Keil -- accepted -- Cuesta Ridge thistle
  Cirsium occidentale var. occidentale (Nutt.) Jeps. -- accepted -- cobwebby thistle
  Cirsium occidentale var. venustum (Greene) Jeps. -- accepted -- cobwebby thistle
  Cirsium ochrocentrum A. Gray -- accepted -- yellowspine thistle
  Cirsium ochrocentrum ssp. martinii P. Barlow -- accepted
  Cirsium ochrocentrum ssp. ochrocentrum A. Gray -- accepted -- yellowspine thistle
  Cirsium ochrocentrum var. helleri (Small) Petr. -- not accepted
  Cirsium odoratum (Muhl. ex W. Bartram) Petr. -- not accepted
  Cirsium olivescens (Rydb.) Petr. -- not accepted -- summer thistle
  Cirsium oreganum Piper -- not accepted
  Cirsium oreophilum (Rydb.) K. Schum. -- not accepted -- crow thistle
  Cirsium osterhoutii (Rydb.) Petr. -- not accepted -- Osterhout's thistle
  Cirsium ownbeyi S.L. Welsh -- accepted -- Ownbey's thistle
  Cirsium pallidum Woot. & Standl. -- not accepted -- pale thistle
  Cirsium palousense Piper -- not accepted
  Cirsium palustre (L.) Scop. -- accepted -- marsh thistle
  Cirsium parryi (A. Gray) Petr. -- accepted -- Parry's thistle, pale thistle, Cloudcroft thistle, Gila thistle, Mogollon thistle
  Cirsium parryi ssp. mogollonicum C. Schaack & G. Goodwin -- not accepted -- Mogollon thistle
  Cirsium parryi ssp. parryi (A. Gray) Petr. -- not accepted -- Parry's thistle
  Cirsium pastoris J.T. Howell -- not accepted -- snowy thistle
  Cirsium peckii L.F. Hend. -- not accepted -- Steens Mountain thistle
  Cirsium perennans (Greene) Woot. & Standl. -- not accepted
  Cirsium perplexans (Rydb.) Petr. -- accepted -- Rocky Mountain thistle, spring thistle
  Cirsium pitcheri (Torr. ex Eaton) Torr. & A. Gray -- accepted -- sand dune thistle, Pitcher's thistle
  Cirsium plattense (Rydb.) Cockerell ex Daniels -- not accepted
  Cirsium polyphyllum (Rydb.) Petr. -- not accepted
  Cirsium praeteriens J.F. Macbr. -- accepted -- Palo Alto thistle
  Cirsium proteanum J.T. Howell -- not accepted
  Cirsium pugnax Sommier & Levier -- not accepted
  Cirsium pulchellum (Greene) Woot. & Standl. -- not accepted
  Cirsium pulchellum ssp. bipinnatum (Eastw.) Petr. -- not accepted
  Cirsium pulchellum ssp. diffusum (Eastw.) Petr. -- not accepted
  Cirsium pulchellum var. glabrescens Petr. -- not accepted
  Cirsium pulcherrimum (Rydb.) K. Schum. -- accepted -- Wyoming thistle
  Cirsium pulcherrimum var. aridum (Dorn) D.J. Keil -- accepted -- Cedar Rim thistle, desert thistle
  Cirsium pulcherrimum var. pulcherrimum (Rydb.) K. Schum. -- accepted -- Wyoming thistle
  Cirsium pumilum Spreng. -- accepted -- pasture thistle
  Cirsium pumilum ssp. hillii (Canby) J.W. Moore & Frankton -- not accepted
  Cirsium pumilum var. hillii (Canby) B. Boivin -- accepted -- Hill's thistle
  Cirsium pumilum var. pumilum Spreng. -- accepted -- pasture thistle
  Cirsium pyrenaicum (Jacq.) All. -- accepted -- Pyrenean thistle
  Cirsium quercetorum (A. Gray) Jeps. -- accepted -- Alameda County thistle
  Cirsium quercetorum var. citrinum Petr. -- not accepted
  Cirsium quercetorum var. mendocinum Petr. -- not accepted
  Cirsium quercetorum var. quercetorum (A. Gray) Jeps. -- not accepted -- Alameda County thistle
  Cirsium quercetorum var. walkerianum (Petr.) Jeps. -- not accepted -- Walker's thistle
  Cirsium quercetorum var. xerolepis Petr. -- not accepted -- Alameda County thistle
  Cirsium remotifolium (Hook.) DC. -- accepted -- fewleaf thistle
  Cirsium remotifolium ssp. oregonense Petr. -- not accepted -- fewleaf thistle
  Cirsium remotifolium ssp. pseudocarlinoides Petr. -- not accepted -- fewleaf thistle
  Cirsium remotifolium ssp. remotifolium (Hook.) DC. -- not accepted -- fewleaf thistle
  Cirsium remotifolium var. odontolepis Petr. -- accepted -- Pacific fringed thistle, fringe-scaled thistle, fewleaf thistle, Mt. Tamalpais thistle
  Cirsium remotifolium var. remotifolium (Hook.) DC. -- accepted -- fewleaf thistle, remote-leaved thistle
  Cirsium remotifolium var. rivulare Jeps. -- accepted -- Klamath thistle, Mendocino thistle
  Cirsium repandum Michx. -- accepted -- sandhill thistle
  Cirsium revolutum (Small) Petr. -- not accepted
  Cirsium rhothophilum S.F. Blake -- accepted -- surf thistle
  Cirsium rothrockii (A. Gray) Petr. -- not accepted -- Rothrock's thistle
  Cirsium rusbyi (Greene) Petr. -- not accepted -- Rusby's thistle
  Cirsium rydbergii Petr. -- accepted -- Rydberg's thistle
  Cirsium scabrum (Poir.) Bonnet & Barratte -- accepted -- rough thistle
  Cirsium scapanolepis Petr. -- not accepted -- mountain slope thistle
  Cirsium scariosum Nutt. -- accepted -- meadow thistle
  Cirsium scariosum var. americanum (A. Gray) D.J. Keil -- accepted -- dinnerplate thistle, sessile thistle, stemless thistle, Tioga thistle
  Cirsium scariosum var. citrinum (Petr.) D.J. Keil -- accepted -- La Graciosa thistle
  Cirsium scariosum var. coloradense (Rydb.) D.J. Keil -- accepted -- Colorado thistle, summer thistle, glory thistle
  Cirsium scariosum var. congdonii (R.J. Moore & Frankton) D.J. Keil -- accepted -- rosette thistle
  Cirsium scariosum var. robustum D.J. Keil -- accepted -- Shasta Valley thistle
  Cirsium scariosum var. scariosum Nutt. -- accepted -- meadow thistle
  Cirsium scariosum var. thorneae S.L. Welsh -- accepted -- meadow thistle
  Cirsium scariosum var. toiyabense D.J. Keil -- accepted -- Toiyabe thistle
  Cirsium scopulorum (Greene) Cockerell ex Daniels -- not accepted -- mountain thistle
  Cirsium setosum (Willd.) Besser ex M. Bieb. -- not accepted
  Cirsium smallii Britton -- not accepted
  Cirsium spathulifolium Rydb. -- not accepted
  Cirsium spinosissimum auct. non (L.) Scop. -- not accepted
  Cirsium stenolepidum Nutt. -- not accepted
  Cirsium subniveum Rydb. -- not accepted -- Jackson Hole thistle, gray thistle
  Cirsium terraenigrae Shinners -- not accepted
  Cirsium texanum Buckley -- accepted -- Texas thistle
  Cirsium texanum var. stenolepis Shinners -- not accepted
  Cirsium tioganum (Congd.) Petr. -- not accepted -- stemless thistle
  Cirsium tioganum var. coloradense (Rydb.) Dorn -- not accepted -- Colorado thistle, stemless thistle
  Cirsium tioganum var. tioganum (Congd.) Petr. -- not accepted -- Tioga thistle
  Cirsium tracyi (Rydb.) Petr. -- accepted -- Tracy's thistle
  Cirsium triacanthum Petr. -- not accepted
  Cirsium turneri Warnock -- accepted -- cliff thistle
  Cirsium tweedyi auct. non (Rydb.) Petr. -- not accepted
  Cirsium tweedyi (Rydb.) Petr. -- not accepted
  Cirsium undulatum (Nutt.) Spreng. -- accepted -- wavyleaf thistle, gray thistle, wavy-leaf thistle
  Cirsium undulatum var. megacephalum (A. Gray) Fernald -- not accepted
  Cirsium undulatum var. tracyi (Rydb.) S.L. Welsh -- not accepted -- Tracy's thistle, gray thistle, wavyleaf thistle
  Cirsium undulatum var. undulatum (Nutt.) Spreng. -- accepted -- wavyleaf thistle, gray thistle, wavy-leaf thistle
  Cirsium utahense Petr. -- not accepted
  Cirsium validus Greene -- accepted -- graceful thistle
  Cirsium vaseyi (A. Gray) Jeps. -- not accepted
  Cirsium vaseyi var. hydrophilum (Greene) Petr. -- not accepted
  Cirsium vernale (Osterh.) Cockerell -- not accepted -- spring thistle
  Cirsium vinaceum Woot. & Standl. -- accepted -- Sacramento Mountains thistle
  Cirsium virginense S.L. Welsh -- not accepted -- virgin thistle
  Cirsium virginianum (L.) Michx. -- accepted -- Virginia thistle
  Cirsium vittatum Small -- not accepted
  Cirsium vulgare (Savi) Ten. -- accepted -- bull thistle, common thistle, spear thistle
  Cirsium walkerianum Petr. -- not accepted
  Cirsium wallowense M. Peck -- not accepted
  Cirsium wheeleri (A. Gray) Petr. -- accepted -- Wheeler's thistle
  Cirsium wrightii A. Gray -- accepted -- Wright's thistle, Wright's marsh thistle
  Cirsium X canalense Petr. -- accepted -- canal thistle
  Cirsium X crassum Petr. -- accepted -- thistle
  Cirsium X erosum (Rydb.) K. Schum. (pro sp.) -- not accepted -- glory thistle
  Cirsium X iowense (Pammel) Fernald (pro sp.) -- accepted -- Iowa thistle
  Cirsium X vancouverense J.W. Moore & Frankton -- accepted -- Vancouver thistle
  Cladanthus Cass. -- accepted
  Cladanthus mixtus (L.) Chevall. -- accepted -- weedy dogfennel
  Clappia A. Gray -- accepted -- clapdaisy
  Clappia suaedifolia A. Gray -- accepted -- fleshy clapdaisy
  Clibadium L. -- accepted -- clibadium
  Clibadium erosum (Sw.) DC. -- accepted -- jackass breadnut
  Clibadium surinamense L. -- accepted
  Cnicus L. -- not accepted -- cnicus
  Cnicus amplifolius Greene -- not accepted
  Cnicus arizonicus A. Gray -- not accepted
  Cnicus benedictus L. -- not accepted -- blessed thistle, blessed-thistle
  Cnicus breweri var. vaseyi A. Gray -- not accepted
  Cnicus calcareus M.E. Jones -- not accepted
  Cnicus drummondii var. acaulescens Rydb. -- not accepted
  Cnicus ochrocentrus (A. Gray) A. Gray -- not accepted
  Cnicus parryi A. Gray -- not accepted
  Cnicus tioganus Congd. -- not accepted
  Cnicus undulatus var. megacephalus A. Gray -- not accepted
  Cnicus wheeleri A. Gray -- not accepted
  Coleosanthus cordifolius (Elliot) Kuntze -- not accepted
  Coleosanthus desertorum (Coville) Coville -- not accepted
  Coleosanthus grandiflorus (Hook.) Kuntze -- not accepted
  Coleosanthus venosus Woot. & Standl. -- not accepted
  Columbiadoria G.L. Nesom -- accepted -- columbiadoria
  Columbiadoria hallii (A. Gray) G.L. Nesom -- accepted -- Hall's columbiadoria
  Complaya gracilis (Rich.) Strother -- not accepted
  Complaya trilobata (L.) Strother -- not accepted
  Condylidium King & H. Rob. -- accepted -- villalba
  Condylidium iresinoides (Kunth) King & H. Rob. -- accepted -- villalba
  Conoclinium DC. -- accepted -- thoroughwort
  Conoclinium betonicifolium (Mill.) R.M. King & H. Rob. -- accepted -- betonyleaf thoroughwort, betonyleaf mistflower
  Conoclinium betonicifolium var. betonicifolium (Mill.) R.M. King & H. Rob. -- accepted
  Conoclinium betonicifolium var. integrifolium (A. Gray) T.F. Patterson -- accepted
  Conoclinium coelestinum (L) DC -- accepted -- blue mistflower
  Conoclinium dissectum A. Gray -- accepted -- palmleaf thoroughwort
  Conoclinium greggii (A. Gray) Small -- not accepted -- palmleaf thoroughwort
  Constancea B.G. Baldw. -- accepted
  Constancea nevinii (A. Gray) B.G. Baldw. -- accepted -- Nevin's woolly sunflower
  Conyza Less. -- accepted -- horseweed
  Conyza apurensis Kunth -- not accepted -- manzanilla horseweed
  Conyza asteroides L. -- not accepted
  Conyza bifoliata Walter -- not accepted
  Conyza bilboana Remy -- not accepted
  Conyza bonariensis (L.) Cronquist -- accepted -- asthmaweed, wavy-leaf fleabane, flax-leaf fleabane, flaxleaved fleabane, hairy fleabane
  Conyza bonariensis var. bonariensis (L.) Cronquist -- not accepted -- asthmaweed
  Conyza bonariensis var. leiotheca (S.F. Blake) Cuatrec. -- not accepted -- asthmaweed
  Conyza canadensis (L.) Cronquist -- accepted -- Canadian horseweed, horseweed, horseweed fleabane, mares tail, Canada horseweed, marestail
  Conyza canadensis var. canadensis (L.) Cronquist -- not accepted -- Canadian horseweed
  Conyza canadensis var. glabrata (A. Gray) Cronquist -- not accepted -- Canadian horseweed
  Conyza canadensis var. pusilla (Nutt.) Cronquist -- not accepted -- Canadian horseweed
  Conyza carolinensis Jacq. -- not accepted
  Conyza chilensis Spreng. -- not accepted
  Conyza cinerea L. -- not accepted
  Conyza cortesii Kunth -- not accepted
  Conyza coulteri A. Gray -- not accepted
  Conyza coulteri var. tenuisecta A. Gray -- not accepted
  Conyza coulteri var. virgata (Benth.) A. Gray -- not accepted
  Conyza eriophylla (A. Gray) Cronquist -- not accepted
  Conyza filaginoides (DC.) Hieron. -- not accepted
  Conyza floribunda Kunth -- accepted -- asthmaweed
  Conyza laevigata (L.C. Rich) Pruski -- accepted -- manzanilla horseweed
  Conyza linifolia L. -- not accepted
  Conyza lobata L. -- not accepted
  Conyza lyrata Kunth -- not accepted
  Conyza odorata L. -- not accepted
  Conyza parva Cronquist -- not accepted
  Conyza primulifolia (Lam.) Cuatrec. & Lourteig -- accepted -- primroseleaf horseweed
  Conyza ramosissima Cronquist -- accepted -- dwarf horseweed, branching conyza
  Conyza salicifolia Mill. -- not accepted
  Conyza schiedeana (Less.) Cronquist -- not accepted
  Conyza sophiifolia Kunth -- not accepted
  Conyza subspathulata Cronquist -- not accepted
  Conyza viscosa Mill. -- not accepted
  Coreocarpus Benth. -- accepted -- coreocarpus
  Coreocarpus arizonicus (A. Gray) S.F. Blake -- accepted -- little lemonhead, Arizona coreocarpus
  Coreopsis L. -- accepted -- tickseed, coreopsis
  Coreopsis alba L. -- not accepted
  Coreopsis angustata Greene -- not accepted
  Coreopsis angustifolia Aiton non L. -- not accepted
  Coreopsis atkinsoniana Douglas ex Lindl. -- not accepted
  Coreopsis aurea Aiton -- not accepted
  Coreopsis auriculata L. -- accepted -- lobed tickseed
  Coreopsis basalis (A. Dietr.) S.F. Blake -- accepted -- rock tickseed, goldenmane tickseed
  Coreopsis basalis var. wrightii (A. Gray) S.F. Blake -- not accepted
  Coreopsis bigelovii (A. Gray) H.M. Hall -- accepted -- Bigelow's tickseed
  Coreopsis californica (Nutt.) H. Sharsm. -- accepted -- California tickseed, Newberry's tickseed
  Coreopsis californica var. californica (Nutt.) H. Sharsm. -- accepted -- California tickseed
  Coreopsis californica var. newberryi (A. Gray) E.B. Sm. -- not accepted -- Newberry's tickseed
  Coreopsis calliopsidea (DC.) A. Gray -- accepted -- leafstem tickseed
  Coreopsis cardaminefolia (DC.) Torr. & A. Gray -- not accepted
  Coreopsis corninsularis Sherff -- not accepted
  Coreopsis crassifolia Aiton -- not accepted
  Coreopsis debilis Sherff -- not accepted
  Coreopsis delphiniifolia Lam. -- accepted -- larkspurleaf tickseed
  Coreopsis delphiniifolia var. chlooidea Sherff -- not accepted
  Coreopsis douglasii (DC.) H.M. Hall -- accepted -- Douglas' tickseed
  Coreopsis drummondii (D. Don) Torr. & A. Gray -- not accepted
  Coreopsis drummondii var. wrightii A. Gray -- not accepted
  Coreopsis falcata Boynt. -- not accepted -- sickle tickseed
  Coreopsis ferulifolia Jacq. -- not accepted
  Coreopsis floridana E.B. Sm. -- not accepted -- Florida tickseed
  Coreopsis gigantea (Kellogg) H.M. Hall -- accepted -- giant coreopsis
  Coreopsis gladiata Walter -- accepted -- coastal plain tickseed, sickle tickseed, Florida tickseed, Texas tickseed, coastalplain tickseed
  Coreopsis gladiata var. linifolia (Nutt.) Cronquist -- not accepted
  Coreopsis grandiflora Hogg ex Sweet -- accepted -- largeflower tickseed, bigflower coreopsis
  Coreopsis grandiflora var. grandiflora Hogg ex Sweet -- not accepted -- largeflower tickseed
  Coreopsis grandiflora var. harveyana (A. Gray) Sherff -- not accepted -- largeflower tickseed
  Coreopsis grandiflora var. inclinata J. Allison -- not accepted
  Coreopsis grandiflora var. longipes (Hook.) Torr. & A. Gray -- not accepted -- largeflower tickseed
  Coreopsis grandiflora var. pilosa Sherff -- not accepted
  Coreopsis grandiflora var. saxicola (Alexander) E.B. Sm. -- not accepted -- largeflower tickseed
  Coreopsis hamiltonii (Elmer) H.K. Sharsmith -- accepted -- Mt. Hamilton tickseed
  Coreopsis helianthoides Beadle -- not accepted
  Coreopsis heterogyna Fernald -- not accepted
  Coreopsis heterolepis Sherff -- not accepted
  Coreopsis integrifolia Poir. -- accepted -- fringeleaf tickseed
  Coreopsis intermedia Sherff -- accepted -- goldenwave tickseed
  Coreopsis lanceolata L. -- accepted -- lanceleaf tickseed, lance coreopsis
  Coreopsis lanceolata var. villosa Michx. -- not accepted
  Coreopsis latifolia Michx. -- accepted -- broadleaf tickseed
  Coreopsis leavenworthii Torr. & A. Gray -- accepted -- Leavenworth's tickseed
  Coreopsis leavenworthii var. curtissii Sherff -- not accepted
  Coreopsis leavenworthii var. garberi A. Gray -- not accepted
  Coreopsis leavenworthii var. lewtonii (Small) Sherff -- not accepted
  Coreopsis lewtonii Small -- not accepted
  Coreopsis linifolia Nutt. -- not accepted -- Texas tickseed
  Coreopsis longifolia Small -- not accepted
  Coreopsis longifolia var. godfreyi Sherff -- not accepted
  Coreopsis longipes Hook. -- not accepted
  Coreopsis major Walter -- accepted -- greater tickseed
  Coreopsis major var. linearis Small -- not accepted
  Coreopsis major var. oemleri (Elliot) Britton ex Small & Vail -- not accepted
  Coreopsis major var. rigida (Nutt.) Boynt. -- not accepted
  Coreopsis major var. stellata (Nutt.) B.L. Rob. -- not accepted
  Coreopsis maritima (Nutt.) Hook. f. -- accepted -- sea dahlia
  Coreopsis newberryi A. Gray -- not accepted
  Coreopsis nudata Nutt. -- accepted -- Georgia tickseed
  Coreopsis nuecensis A. Heller -- accepted -- crown tickseed
  Coreopsis nuecensoides E.B. Sm. -- accepted -- Rio Grande tickseed
  Coreopsis oniscicarpa Fernald -- not accepted
  Coreopsis oniscicarpa var. simulans Fernald -- not accepted
  Coreopsis palmata Nutt. -- accepted -- stiff tickseed, wedgeleaf coreopsis
  Coreopsis parviflora Jacq. -- not accepted
  Coreopsis pubescens Elliot -- accepted -- star tickseed, hairy coreopsis
  Coreopsis pubescens var. debilis (Sherff) E.B. Sm. -- not accepted -- star tickseed
  Coreopsis pubescens var. pubescens Elliot -- not accepted -- star tickseed
  Coreopsis pubescens var. robusta A. Gray ex Eames -- not accepted -- star tickseed
  Coreopsis pulchra Boynt. -- accepted -- woodland tickseed
  Coreopsis reptans L. -- not accepted
  Coreopsis rosea Nutt. -- accepted -- pink tickseed
  Coreopsis saxicola Alexander -- not accepted
  Coreopsis saxicola var. duncanii Sherff -- not accepted
  Coreopsis saxicoloidea Sherff -- not accepted
  Coreopsis similis Boynt. -- not accepted
  Coreopsis stenophylla Boynt. -- not accepted
  Coreopsis stillmanii (A. Gray) S.F. Blake -- accepted -- Stillman's tickseed
  Coreopsis stillmanii var. jonesii Sherff -- not accepted
  Coreopsis tinctoria Nutt. -- accepted -- golden tickseed, Atkinson's tickseed, plains coreopsis, plains tickseed
  Coreopsis tinctoria var. atkinsoniana (Douglas ex Lindl.) H.M. Parker ex E.B. Sm. -- not accepted -- Atkinson's tickseed
  Coreopsis tinctoria var. imminuta Sherff -- not accepted
  Coreopsis tinctoria var. similis (Boynt.) H.M. Parker -- not accepted -- golden tickseed
  Coreopsis tinctoria var. tinctoria Nutt. -- not accepted -- golden tickseed
  Coreopsis tripteris L. -- accepted -- tall tickseed, Atlantic coreopsis
  Coreopsis tripteris var. deamii Standl. -- not accepted
  Coreopsis tripteris var. intercedens Standl. -- not accepted
  Coreopsis tripteris var. smithii Sherff -- not accepted
  Coreopsis tripteris var. subrhomboidea Sherff -- not accepted
  Coreopsis verticillata L. -- accepted -- whorled tickseed
  Coreopsis wrightii (A. Gray) H.M. Parker -- not accepted -- rock tickseed
  Corethrogyne DC. -- accepted -- sandaster
  Corethrogyne californica DC. -- not accepted -- California sandaster
  Corethrogyne californica var. californica DC. -- not accepted -- California sandaster
  Corethrogyne californica var. lyonii S.F. Blake -- not accepted -- California sandaster
  Corethrogyne californica var. obovata (Benth.) Kuntze -- not accepted -- California sandaster
  Corethrogyne filaginifolia (Hook. & Arn.) Nutt. -- accepted -- common sandaster, California sandaster, whiteleaf sandaster
  Corethrogyne filaginifolia var. bernardina (Abrams) H.M. Hall -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. brevicula (Greene) Canby -- not accepted
  Corethrogyne filaginifolia var. californica (DC.) J.P. Saroyan -- not accepted
  Corethrogyne filaginifolia var. filaginifolia (Hook. & Arn.) Nutt. -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. glomerata H.M. Hall -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. hamiltonensis D.D. Keck -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. incana (Nutt.) Canby -- not accepted -- San Diego sandaster
  Corethrogyne filaginifolia var. latifolia H.M. Hall -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. linifolia H.M. Hall -- not accepted -- Del Mar sand aster, Del Mar Mesa sandaster
  Corethrogyne filaginifolia var. peirsonii Canby -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. pinetorum I.M. Johnst. -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. rigida A. Gray -- not accepted
  Corethrogyne filaginifolia var. robusta Greene -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. sessilis (Greene) Canby -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. virgata (Benth.) A. Gray -- not accepted -- common sandaster
  Corethrogyne filaginifolia var. viscidula (Greene) D.D. Keck -- not accepted -- common sandaster
  Corethrogyne flagellaris Greene -- not accepted
  Corethrogyne floccosa Greene -- not accepted
  Corethrogyne incana Nutt. -- not accepted
  Corethrogyne leucophylla (Lindl.) Jeps. -- not accepted -- whiteleaf sandaster
  Corethrogyne linifolia (H.M. Hall) Ferris -- not accepted
  Corethrogyne obovata Benth. -- not accepted
  Corethrogyne scabra Greene -- not accepted
  Corethrogyne sessilis Greene -- not accepted
  Corethrogyne tomentella (Hook. & Arn.) Torr. & A. Gray -- not accepted
  Corethrogyne viscidula Greene -- not accepted
  Cosmos Cav. -- accepted -- cosmos
  Cosmos bipinnatus Cav. -- accepted -- garden cosmos
  Cosmos caudatus Kunth -- accepted -- wild cosmos
  Cosmos parviflorus (Jacq.) Pers. -- accepted -- southwestern cosmos
  Cosmos sulphureus Cav. -- accepted -- sulphur cosmos
  Cota J.Gay -- accepted
  Cota altissima (L.) J. Gay -- not accepted
  Cota tinctoria (L.) J. Gay -- accepted -- golden chamomile
  Cotula L. -- accepted -- waterbuttons, water buttons
  Cotula australis (Sieber ex Spreng.) Hook. f. -- accepted -- Australian waterbuttons
  Cotula coronopifolia L. -- accepted -- common brassbuttons, brassbuttons
  Cotula mexicana (DC.) Cabrera -- accepted -- Mexican brassbuttons
  Cotula verbesina L. -- not accepted
  Cotula viscosa L. -- not accepted
  Crassina elegans (Jacq.) Kuntze -- not accepted
  Crassina grandiflora (Nutt.) Kuntze -- not accepted
  Crassina multiflora (L.) Kuntze -- not accepted
  Crassocephalum Moench -- accepted -- ragleaf
  Crassocephalum crepidioides (Benth.) S. Moore -- accepted -- redflower ragleaf
  Crassocephalum vitellinum (Benth.) S. Moore -- accepted
  Crepis L. -- accepted -- hawksbeard
  Crepis acuminata Nutt. -- accepted -- tapertip hawksbeard, long-leaf hawksbeard, longleaf hawksbeard
  Crepis acuminata ssp. acuminata Nutt. -- not accepted -- tapertip hawksbeard, longleaf hawksbeard
  Crepis acuminata ssp. pluriflora Babc. & Stebbins -- not accepted -- tapertip hawksbeard
  Crepis acuminata ssp. typica Babc. & Stebbins -- not accepted
  Crepis alpicola (Rydb.) A. Nelson -- not accepted
  Crepis atribarba A. Heller -- accepted -- slender hawksbeard, hawksbeard
  Crepis atribarba ssp. atribarba A. Heller -- not accepted -- slender hawksbeard
  Crepis atribarba ssp. cytotaxonomicorum (B. Boivin) W.A. Weber -- not accepted
  Crepis atribarba ssp. originalis (Babc. & Stebbins) Babc. & Stebbins -- not accepted -- slender hawksbeard
  Crepis atribarba ssp. typicus Babc. & Stebbins -- not accepted
  Crepis atribarba var. cytotaxonomicorum B. Boivin -- not accepted
  Crepis bakeri Greene -- accepted -- Baker's hawksbeard
  Crepis bakeri ssp. bakeri Greene -- accepted -- Baker's hawksbeard
  Crepis bakeri ssp. cusickii (Eastw.) Babc. & Stebbins -- accepted -- Cusick's hawksbeard
  Crepis bakeri ssp. idahoensis Babc. & Stebbins -- accepted -- Idaho hawksbeard
  Crepis barbata L. -- not accepted
  Crepis barberi Greenm. -- not accepted
  Crepis barbigera Leiberg ex Coville -- accepted
  Crepis biennis L. -- accepted -- rough hawksbeard
  Crepis bursifolia L. -- accepted -- Italian hawksbeard
  Crepis capillaris (L.) Wallr. -- accepted -- smooth hawksbeard, smooth hawk's-beard
  Crepis elegans Hook. -- accepted -- elegant hawksbeard
  Crepis foetida L. -- accepted -- stinking hawksbeard
  Crepis foetida var. foetida L. -- not accepted
  Crepis foetida var. rhoeadifolia (M. Bieb.) Celak. -- not accepted
  Crepis glauca (Nutt.) Torr. & A. Gray -- not accepted
  Crepis glauca ssp. barberi (Greenm.) Babc. & Stebbins -- not accepted
  Crepis glaucella Rydb. -- not accepted
  Crepis intermedia A. Gray -- accepted -- limestone hawksbeard, gray hawksbeard
  Crepis japonica (L.) Benth. -- not accepted
  Crepis kotschyana Boiss. -- accepted
  Crepis modocensis Greene -- accepted -- Modoc hawksbeard, common hawksbeard, Siskiyou hawksbeard
  Crepis modocensis ssp. glareosa (Piper) Babc. & Stebbins -- accepted -- Modoc hawksbeard
  Crepis modocensis ssp. modocensis Greene -- accepted -- Modoc hawksbeard
  Crepis modocensis ssp. rostrata (Coville) Babc. & Stebbins -- accepted -- Modoc hawksbeard
  Crepis modocensis ssp. subacaulis (Kellogg) Babc. & Stebbins -- accepted -- Modoc hawksbeard, Siskiyou hawksbeard
  Crepis modocensis ssp. typica Babc. & Stebbins -- not accepted
  Crepis modocensis var. rostrata (Coville) B. Boivin -- not accepted
  Crepis monticola Coville -- accepted -- mountain hawksbeard
  Crepis nana Richardson -- accepted -- dwarf alpine hawksbeard, small hawksbeard, tiny hawksbeard
  Crepis nana ssp. clivicola Leggett -- not accepted -- dwarf alpine hawksbeard
  Crepis nana ssp. nana Richardson -- not accepted -- dwarf alpine hawksbeard
  Crepis nana ssp. ramosa Babc. -- not accepted -- dwarf alpine hawksbeard
  Crepis nana ssp. typica Babc. -- not accepted
  Crepis nana var. lyratifolia (Turcz.) Hultén -- not accepted
  Crepis nana var. ramosa (Babc.) Cronquist -- not accepted
  Crepis neomexicana Woot. & Standl. -- not accepted
  Crepis nicaeensis Balbis ex Pers. -- accepted -- Turkish hawksbeard
  Crepis occidentalis Nutt. -- accepted -- largeflower hawksbeard, large-flower hawk's-beard, western hawksbeard
  Crepis occidentalis ssp. conjuncta (Jeps.) Babc. & Stebbins -- accepted -- largeflower hawksbeard
  Crepis occidentalis ssp. costata (A. Gray) Babc. & Stebbins -- accepted -- largeflower hawksbeard
  Crepis occidentalis ssp. occidentalis Nutt. -- accepted -- largeflower hawksbeard
  Crepis occidentalis ssp. pumila (Rydb.) Babc. & Stebbins -- accepted -- largeflower hawksbeard
  Crepis occidentalis ssp. typica Babc. & Stebbins -- not accepted
  Crepis occidentalis var. costata A. Gray -- not accepted
  Crepis occidentalis var. nevadensis Kellogg -- not accepted
  Crepis occidentalis var. pumila (Rydb.) Babc. & Stebbins -- not accepted
  Crepis paludosa (L.) Moench -- accepted
  Crepis pannonica (Jacq.) K. Koch -- accepted -- pasture hawksbeard
  Crepis perplexans Rydb. -- not accepted
  Crepis platyphylla Greene -- not accepted
  Crepis pleurocarpa A. Gray -- accepted -- nakedstem hawksbeard
  Crepis pulchra L. -- accepted -- smallflower hawksbeard, hawksbeard
  Crepis rigida Waldst. & Kit. -- not accepted
  Crepis riparia A. Nelson -- not accepted
  Crepis rubra L. -- accepted -- red hawksbeard
  Crepis runcinata (James) Torr. & A. Gray -- accepted -- fiddleleaf hawksbeard, dandelion hawksbeard, fiddle-leaf hawk's-beard, fiddle-leaf hawksbeard
  Crepis runcinata ssp. andersonii (A. Gray) Babc. & Stebbins -- accepted -- Anderson's hawksbeard
  Crepis runcinata ssp. barberi (Greenm.) Babc. & Stebbins -- accepted -- Barber's hawksbeard
  Crepis runcinata ssp. glauca (Nutt.) Babc. & Stebbins -- accepted -- fiddleleaf hawksbeard
  Crepis runcinata ssp. hallii Babc. & Stebbins -- accepted -- Hall's hawksbeard
  Crepis runcinata ssp. hispidulosa (Howell ex Rydb.) Babc. & Stebbins -- accepted -- fiddleleaf hawksbeard
  Crepis runcinata ssp. imbricata Babc. & Stebbins -- accepted -- fiddleleaf hawksbeard
  Crepis runcinata ssp. runcinata (James) Torr. & A. Gray -- accepted -- fiddleleaf hawksbeard, fiddle-leaf hawk's-beard, dandelion hawksbeard
  Crepis runcinata ssp. typica Babc. & Stebbins -- not accepted
  Crepis runcinata var. andersonii (A. Gray) Cronquist -- not accepted
  Crepis runcinata var. barberi (Greenm.) B.L. Turner -- not accepted
  Crepis runcinata var. glauca (Nutt.) B. Boivin -- not accepted
  Crepis runcinata var. hispidulosa Howell ex Rydb. -- not accepted
  Crepis runcinata var. imbricata (Babc. & Stebbins) M. Peck -- not accepted
  Crepis setosa Haller f. -- accepted -- bristly hawksbeard, rough hawksbeard
  Crepis tectorum L. -- accepted -- narrowleaf hawksbeard, narrowleaved hawk's beard, narrow-leaf hawk's-beard
  Crepis vesicaria L. -- accepted -- beaked hawksbeard
  Crepis vesicaria ssp. haenseleri (Boiss. ex DC.) P.D. Sell -- not accepted
  Crepis vesicaria ssp. taraxacifolia (Thuill.) Thell. -- not accepted -- beaked hawksbeard
  Crepis vesicaria ssp. vesicaria L. -- not accepted
  Crepis vesicaria var. taraxacifolia (Thuill.) B. Boivin -- not accepted
  Crepis zacintha (L.) Babc. -- accepted -- striped hawksbeard
  Critonia P. Br. -- accepted -- thoroughwort
  Critonia portoricensis (Urb.) Britton & P. Wilson -- accepted -- Puerto Rico thoroughwort
  Crocidium Hook. -- accepted -- spring-gold
  Crocidium multicaule Hook. -- accepted -- common spring-gold
  Crockeria chrysantha Greene ex A. Gray -- not accepted
  Croptilon Raf. -- accepted -- scratchdaisy
  Croptilon divaricatum (Nutt.) Raf. -- accepted -- slender scratchdaisy, goldenweed
  Croptilon divaricatum var. graniticum (E.B. Sm.) Shinners -- not accepted
  Croptilon divaricatum var. hirtellum (Shinners) Shinners -- not accepted
  Croptilon divaricatum var. hookerianum (Torr. & A. Gray) Shinners -- not accepted
  Croptilon hookerianum (Torr. & A. Gray) House -- accepted -- Hooker's scratchdaisy
  Croptilon hookerianum var. graniticum (E.B. Sm.) E.B. Sm. -- accepted -- Hooker's scratchdaisy
  Croptilon hookerianum var. hookerianum (Torr. & A. Gray) House -- accepted -- Hooker's scratchdaisy
  Croptilon hookerianum var. validum (Rydb.) E.B. Sm. -- accepted -- Hooker's scratchdaisy
  Croptilon rigidifolium (E.B. Sm.) E.B. Sm. -- accepted -- stiffleaf scratchdaisy
  Crupina (Pers.) DC. -- accepted -- crupina
  Crupina vulgaris Cass. -- accepted -- common crupina, bearded creeper
  Crupina vulgaris var. brachypappa P. Beauv. -- accepted
  Crupina vulgaris var. vulgaris Cass. -- accepted -- common crupina
  Cuniculotinus Urbatsch, R.P. Roberts & Neubig -- accepted
  Cuniculotinus gramineus (H.M. Hall) Urbatsch, R.P. Roberts & Neubig -- accepted -- Panamint rock goldenrod
  Cupularia viscosa (L.) Gren. & Godr. -- not accepted
  Curio P.V.Heath -- accepted
  Curio talinoides (DC.) P.V. Heath -- accepted
  Curio talinoides var. mandraliscae (Tineo) P.V. Heath -- accepted -- blue finger
  Cyanopsis Cass. -- not accepted -- knapweed
  Cyanopsis muricata (L.) Dostál -- not accepted -- Morocco knapweed
  Cyanthillium Blume -- accepted -- ironweed
  Cyanthillium cinereum (L.) H. Rob. -- accepted -- little ironweed
  Cyclachaena Fresen. -- accepted
  Cyclachaena xanthifolia Fresen. -- not accepted
  Cymbia occidentalis (Nutt.) Standl. -- not accepted
  Cymophora B.L. Rob. -- accepted -- cymophora
  Cymophora accedens (S.F. Blake) B.L. Turner & A. Powell -- accepted -- cymophora
  Cynara L. -- accepted -- cynara
  Cynara cardunculus L. -- accepted -- cardoon, artichoke, artichoke thistle, wild artichoke
  Cynara cardunculus ssp. cardunculus L. -- accepted -- cardoon, artichoke, artichoke thistle
  Cynara cardunculus ssp. flavescens Wiklund -- accepted
  Cynara scolymus L. -- accepted -- globe artichoke
  Cynthia dandelion (L) DC -- not accepted
  Cynthia montana (Michx.) Standl. -- not accepted
  Cynthia virginica (L.) D. Don non Hyoseris virginica L. -- not accepted
  Cynthia viridis Standl. -- not accepted
  Dahlia Cav. -- accepted -- dahlia
  Dahlia coccinea Cav. -- accepted -- red dahlia
  Dahlia pinnata Cav. -- accepted -- pinnate dahlia
  Dahlia rosea Cav. -- not accepted
  Deinandra Greene -- accepted
  Deinandra arida (D.D. Keck) B.G. Baldw. -- accepted -- Redrock tarweed
  Deinandra bacigalupii B.G. Baldw. -- accepted -- Livermore moonshine
  Deinandra clementina (Brandegee) B.G. Baldw. -- accepted -- Catalina tarweed
  Deinandra conjugens (D.D. Keck) B.G. Baldw. -- accepted -- Otay tarweed, Otay tarplant
  Deinandra corymbosa (DC.) B.G. Baldw. -- accepted -- coastal moonshine, coastal tarweed
  Deinandra corymbosa ssp. corymbosa (DC.) B.G. Baldw. -- not accepted
  Deinandra corymbosa ssp. macrocephala (Nutt.) B.G. Baldw. -- not accepted
  Deinandra fasciculata (DC.) Greene -- accepted -- clustered tarweed
  Deinandra floribunda (A. Gray) Davidson & Moxley -- accepted -- Tecate tarweed
  Deinandra halliana (D.D. Keck) B.G. Baldw. -- accepted -- Hall's tarweed
  Deinandra increscens (H.M. Hall ex D.D. Keck) B.G. Baldw. -- accepted -- grassland moonshine
  Deinandra increscens ssp. foliosa (Hoover) B.G. Baldw. -- not accepted
  Deinandra increscens ssp. increscens (H.M. Hall ex D.D. Keck) B.G. Baldw. -- accepted -- grassland tarweed
  Deinandra increscens ssp. villosa (Tanowitz) B.G. Baldw. -- accepted -- grassland tarweed, Gaviota tarplant
  Deinandra kelloggii (Greene) Greene -- accepted -- Kellogg's tarweed
  Deinandra lobbii (Greene) Greene -- accepted -- threeray tarweed
  Deinandra minthornii (Jeps.) B.G. Baldw. -- accepted -- Santa Susana tarweed
  Deinandra mohavensis (D.D. Keck) B.G. Baldw. -- accepted -- Mojave tarweed
  Deinandra pallida (D.D. Keck) B.G. Baldw. -- accepted -- Kern tarweed
  Deinandra paniculata (A. Gray) Davidson & Moxley -- accepted -- grassland tarweed, San Diego tarweed
  Deinandra pentactis (D.D. Keck) B.G. Baldw. -- accepted -- Salinas River tarweed
  Delairea Lem. -- accepted -- Cape-ivy, Cape ivy
  Delairea odorata Lem. -- accepted -- Cape-ivy, Cape ivy, German ivy, Italian ivy
  Dendranthema (DC.) Des Moul. -- accepted -- arctic daisy
  Dendranthema arcticum (L.) Tzvelev -- not accepted -- arctic daisy
  Dendranthema arcticum ssp. arcticum (L.) Tzvelev -- not accepted -- arctic daisy
  Dendranthema arcticum ssp. polare (Hultén) Heywood -- not accepted -- arctic daisy
  Dendranthema grandiflorum Kitam. -- not accepted
  Dendranthema hultenii (A. Löve & D. Löve) Tzvelev -- not accepted
  Dendranthema indicum (L.) Des Moul. -- accepted -- mother's daisy
  Dendranthema morifolium (Ramat.) Tzvelev -- not accepted -- florist's daisy
  Dendranthema X grandiflorum Kitam. -- not accepted -- florist's daisy
  Diaperia Nutt. -- accepted
  Diaperia candida (Torr. & A. Gray) Benth. -- accepted -- silver pygmycudweed
  Diaperia drummondii (Torr. & A. Gray) Benth. -- not accepted
  Diaperia multicaulis (DC.) Nutt. -- not accepted
  Diaperia prolifera (Nutt. ex DC.) Nutt. -- accepted -- bighead pygmycudweed, big-head rabbit-tobacco
  Diaperia prolifera var. barnebyi Morefield -- accepted -- Barneby's rabbit-tobacco
  Diaperia prolifera var. prolifera (Nutt. ex DC.) Nutt. -- accepted -- bighead pygmycudweed, big-head rabbit-tobacco
  Diaperia verna (Raf.) Morefield -- accepted -- spring pygmycudweed
  Diaperia verna var. drummondii (Torr. & A. Gray) Morefield -- accepted -- spring pygmycudweed
  Diaperia verna var. verna (Raf.) Morefield -- accepted -- spring pygmycudweed
  Dichaetophora A. Gray -- accepted -- dichaetophora
  Dichaetophora campestris A. Gray -- accepted -- plainsdaisy
  Dicoria Torr. ex A. Gray -- accepted -- twinbugs, dicoria
  Dicoria brandegeei A. Gray -- not accepted
  Dicoria canescens A. Gray -- accepted -- desert twinbugs
  Dicoria canescens ssp. brandegeei (A. Gray) Kartesz -- not accepted -- desert twinbugs, Brandegee's twinbugs
  Dicoria canescens ssp. canescens A. Gray -- not accepted -- desert twinbugs
  Dicoria canescens ssp. clarkiae (Kennedy) D.D. Keck -- not accepted -- desert twinbugs
  Dicoria canescens ssp. hispidula (Rydb.) D.D. Keck -- not accepted -- desert twinbugs
  Dicoria canescens ssp. wetherillii (Eastw.) Kartesz -- not accepted -- desert twinbugs
  Dicoria canescens var. brandegeei (A. Gray) Cronquist -- not accepted
  Dicoria canescens var. hispidula (Rydb.) Cronquist -- not accepted
  Dicoria canescens var. wetherillii (Eastw.) Cronquist -- not accepted
  Dicoria clarkiae Kennedy -- not accepted
  Dicoria oblongifolia Rydb. -- not accepted
  Dicoria paniculata Eastw. -- not accepted
  Dicoria wetherillii Eastw. -- not accepted
  Dicranocarpus A. Gray -- accepted -- dicranocarpus
  Dicranocarpus parviflorus A. Gray -- accepted -- pitchfork
  Dieteria Nutt. -- accepted
  Dieteria asteroides Torr. -- accepted -- fall tansyaster
  Dieteria asteroides var. asteroides Torr. -- accepted
  Dieteria asteroides var. glandulosa (B.L. Turner) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria asteroides var. lagunensis (D.D. Keck) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria bigelovii (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria bigelovii var. bigelovii (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria bigelovii var. commixta (Greene) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria bigelovii var. mucronata (Greene) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria canescens (Pursh) Nutt. -- accepted -- hoary-aster, hoary tansyaster
  Dieteria canescens var. ambigua (B.L. Turner) D.R. Morgan & R.L. Hartm. -- accepted -- hoary tansyaster
  Dieteria canescens var. aristata (Eastw.) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria canescens var. canescens (Pursh) Nutt. -- accepted
  Dieteria canescens var. glabra (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted -- hoary tansyaster
  Dieteria canescens var. incana (Lindl.) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria canescens var. leucanthemifolia (Greene) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria canescens var. nebraskana (B.L. Turner) D.R. Morgan & R.L. Hartm. -- accepted -- Nebraska tansyaster
  Dieteria canescens var. sessiliflora (Nutt.) D.R. Morgan & R.L. Hartm. -- accepted -- hoary tansyaster
  Dieteria canescens var. shastensis (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted
  Dieteria canescens var. ziegleri (Munz) D.R. Morgan & R.L. Hartm. -- accepted -- Ziegler's tansyaster
  Dieteria divaricata Nutt. -- not accepted
  Dieteria gracilis Nutt. non Aster gracilis Nutt. -- not accepted
  Dieteria incana (Lindl.) Torr. & A. Gray -- not accepted
  Dieteria pulverulenta Nutt. -- not accepted
  Dieteria sessiliflora (Nutt.) Greene -- not accepted
  Dieteria spinulosa (Pursh) Nutt. -- not accepted
  Dieteria viscosa Nutt. -- not accepted
  Dimeresia A. Gray -- accepted -- dimeresia
  Dimeresia howellii A. Gray -- accepted -- doublet
  Dimorphotheca Moench -- accepted -- Cape marigold
  Dimorphotheca annua Less. -- not accepted
  Dimorphotheca aurantiaca DC. non Horton -- not accepted
  Dimorphotheca ecklonis DC. -- not accepted
  Dimorphotheca pluvialis (L.) Moench -- accepted -- weather prophet
  Dimorphotheca sinuata DC. -- accepted -- glandular Cape marigold
  Dimorphotheca tragus (Aiton) B. Nord. -- accepted -- Cape marigold
  Diplactis alpina (L.) Semple -- not accepted
  Diplactis alpina ssp. vierhapperi (Onno) Semple -- not accepted
  Diplopappus ericoides Less. -- not accepted
  Diplopappus incanus Lindl. -- not accepted
  Diplopappus lutescens Lindl. ex DC. -- not accepted
  Diplopappus pinnatifidus Hook. -- not accepted
  Diplostelma bellioides A. Gray -- not accepted
  Distasis concinna Hook. & Arn. -- not accepted
  Dittrichia Greuter -- accepted -- dittrichia
  Dittrichia graveolens (L.) Greuter -- accepted -- stinkwort
  Dittrichia viscosa (L.) Greuter -- accepted -- false yellowhead
  Doellingeria Nees -- accepted -- whitetop, doellingeria
  Doellingeria humilis (Willd.) Britton -- not accepted
  Doellingeria infirma (Michx.) Greene -- accepted -- cornel-leaf whitetop
  Doellingeria ptarmicoides Nees -- not accepted
  Doellingeria reticulata (Pursh) Greene -- not accepted
  Doellingeria scabra (Thunb.) Nees -- accepted
  Doellingeria sericocarpoides Small -- accepted -- southern whitetop
  Doellingeria umbellata (Mill.) Nees -- accepted -- parasol whitetop, parasol flat-top white aster
  Doellingeria umbellata ssp. pubens (A. Gray) Á. Löve & D. Löve -- not accepted
  Doellingeria umbellata var. latifolia (A. Gray) House -- not accepted
  Doellingeria umbellata var. pubens (A. Gray) Britton -- accepted -- parasol whitetop
  Doellingeria umbellata var. umbellata (Mill.) Nees -- accepted -- parasol whitetop
  Doronicum L. -- accepted -- false leopardbane
  Doronicum acaule Walter -- not accepted
  Doronicum austriacum Jacq. -- accepted
  Doronicum caucasicum M. Bieb. -- not accepted
  Doronicum cordatum Lam. -- not accepted
  Doronicum orientale Hoffmann -- accepted -- oriental leopard's-bane, oriental false leopardbane
  Doronicum pardalianches L. -- accepted -- great false leopardbane
  Doronicum plantagineum L. -- accepted -- plantain false leopardbane
  Dracopis Cass. -- not accepted -- coneflower
  Dracopis amplexicaulis (Vahl) Cass. -- not accepted -- clasping coneflower, clasping-coneflower
  Dubautia Gaudich. -- accepted -- dubautia
  Dubautia arborea (A. Gray) D.D. Keck -- accepted -- Mauna Kea dubautia
  Dubautia ciliolata (DC.) D.D. Keck -- accepted -- lava dubautia
  Dubautia ciliolata ssp. ciliolata (DC.) D.D. Keck -- accepted -- lava dubautia
  Dubautia ciliolata ssp. glutinosa G.D. Carr -- accepted -- lava dubautia
  Dubautia ciliolata var. juniperoides (A. Gray) D.D. Keck -- not accepted
  Dubautia ciliolata var. trinervia Hillebr. -- not accepted
  Dubautia coriacea (Sherff) D.D. Keck -- not accepted
  Dubautia dolosa (O. Deg. & Sherff) G.D. Carr -- not accepted -- Maui dubautia
  Dubautia herbstobatae G.D. Carr -- accepted -- Keaau Valley dubautia, na`ena`e
  Dubautia hillebrandii (H. Mann) D.D. Keck -- not accepted
  Dubautia imbricata H. St. John & G.D. Carr -- accepted -- bog dubautia
  Dubautia imbricata ssp. acronaea G.D. Carr -- accepted -- bog dubautia
  Dubautia imbricata ssp. imbricata H. St. John & G.D. Carr -- accepted -- bog dubautia, naenae
  Dubautia kenwoodii G.D. Carr -- accepted -- Kalalau rim dubautia, naenae
  Dubautia knudsenii Hillebr. -- accepted -- forest dubautia
  Dubautia knudsenii ssp. filiformis G.D. Carr -- accepted -- forest dubautia
  Dubautia knudsenii ssp. knudsenii Hillebr. -- accepted -- forest dubautia
  Dubautia knudsenii ssp. nagatae (H. St. John) G.D. Carr -- accepted -- forest dubautia
  Dubautia knudsenii var. degeneri Sherff -- not accepted
  Dubautia kohalae (Skottsb.) H. St. John -- not accepted
  Dubautia laevigata A. Gray -- accepted -- smooth dubautia
  Dubautia laevigata var. parvifolia Sherff -- not accepted
  Dubautia latifolia (A. Gray) D.D. Keck -- accepted -- koholapehu, na`ena`e
  Dubautia laxa Hook. & Arn. -- accepted -- na`ena`e pua melemele
  Dubautia laxa ssp. bryanii (O. Deg. & Sherff) G.D. Carr -- accepted -- na`ena`e pua melemele
  Dubautia laxa ssp. hirsuta (Hillebr.) G.D. Carr -- accepted -- na`ena`e pua melemele
  Dubautia laxa ssp. laxa Hook. & Arn. -- accepted -- na`ena`e pua melemele
  Dubautia laxa ssp. pseudoplantaginea (Skottsb.) G.D. Carr -- accepted -- na`ena`e pua melemele
  Dubautia laxa var. bryanii O. Deg. & Sherff -- not accepted
  Dubautia laxa var. greenwelliae O. Deg. & Sherff -- not accepted
  Dubautia laxa var. hirsuta Hillebr. -- not accepted
  Dubautia laxa var. hispida Sherff -- not accepted
  Dubautia laxa var. intercedens O. Deg., I. Deg. & Sherff -- not accepted
  Dubautia laxa var. obovata Sherff -- not accepted
  Dubautia laxa var. pedicellata Rock -- not accepted
  Dubautia laxa var. pseudoplantaginea Skottsb. -- not accepted
  Dubautia laxa var. skottsbergii Sherff -- not accepted
  Dubautia laxa var. waianensis O. Deg. & Sherff -- not accepted
  Dubautia linearis (Gaudich.) D.D. Keck -- accepted -- shrubland dubautia
  Dubautia linearis ssp. hillebrandii (H. Mann) G.D. Carr -- accepted -- Hillebrand's dubautia
  Dubautia linearis ssp. linearis (Gaudich.) D.D. Keck -- accepted -- shrubland dubautia
  Dubautia linearis ssp. opposita (Sherff) G.D. Carr -- accepted -- shrubland dubautia
  Dubautia linearis var. opposita (Sherff) D.D. Keck -- not accepted
  Dubautia lonchophylla (Sherff) D.D. Keck -- not accepted
  Dubautia magnifolia Sherff -- not accepted
  Dubautia menziesii (A. Gray) D.D. Keck -- accepted -- mountain dubautia
  Dubautia menziesii var. angustifolia (Sherff) D.D. Keck -- not accepted
  Dubautia microcephala Skottsb. -- accepted -- Kauai dubautia
  Dubautia molokaiensis var. oppositifolia (Sherff) D.D. Keck -- not accepted
  Dubautia molokaiensis var. stipitata (Sherff) D.D. Keck -- not accepted
  Dubautia montana var. longifolia (Sherff) D.D. Keck -- not accepted
  Dubautia montana var. robustior (Sherff) D.D. Keck -- not accepted
  Dubautia nagatae H. St. John -- not accepted
  Dubautia paleata A. Gray -- accepted -- na`ena`e pua kea
  Dubautia pauciflorula H. St. John & G.D. Carr -- accepted -- Wahiawa Bog dubautia, na`ena`e
  Dubautia plantaginea Gaudich. -- accepted -- plantainleaf dubautia
  Dubautia plantaginea ssp. humilis G.D. Carr -- accepted -- plantainleaf dubautia, na`ena`e, naenae
  Dubautia plantaginea ssp. magnifolia (Sherff) G.D. Carr -- accepted -- plantainleaf dubautia, naenae, na`ena`e
  Dubautia plantaginea ssp. plantaginea Gaudich. -- accepted -- plantainleaf dubautia
  Dubautia plantaginea var. acridentata Sherff -- not accepted
  Dubautia plantaginea var. glandulosa H. St. John -- not accepted
  Dubautia plantaginea var. pauoaensis H. St. John -- not accepted
  Dubautia plantaginea var. platyphylla Hillebr. -- not accepted
  Dubautia plantaginea var. strigosa Skottsb. -- not accepted
  Dubautia platyphylla (A. Gray) D.D. Keck -- accepted -- cinderslope dubautia
  Dubautia platyphylla var. leptophylla (Sherff) D.D. Keck -- not accepted
  Dubautia raillardioides Hillebr. -- accepted -- na`ena`e `ula
  Dubautia reticulata (Sherff) D.D. Keck -- accepted -- netvein dubautia
  Dubautia rockii (Sherff) D.D. Keck -- not accepted
  Dubautia scabra (DC.) D.D. Keck -- accepted -- rough dubautia
  Dubautia scabra ssp. leiophylla (A. Gray) G.D. Carr -- accepted -- rough dubautia
  Dubautia scabra ssp. scabra (DC.) D.D. Keck -- accepted -- rough dubautia
  Dubautia scabra var. leiophylla (A. Gray) D.D. Keck -- not accepted
  Dubautia scabra var. munroi (Sherff) D.D. Keck -- not accepted
  Dubautia sherffiana Fosberg -- accepted -- Waianae Range dubautia
  Dubautia sherffiana var. paucinervia (O. Deg. & Sherff) D.R. Herbst -- not accepted
  Dubautia struthioloides (A. Gray) D.D. Keck -- not accepted
  Dubautia syndetica G.D. Carr & D.H. Lorence -- accepted -- Wahiawa dubautia
  Dubautia ternifolia (Sherff) D.D. Keck -- not accepted
  Dubautia thyrsiflora var. cernua (Sherff) D.D. Keck -- not accepted
  Dubautia waialealae Rock -- accepted -- Waialeale dubautia, naenae, na`ena`e
  Dubautia waianapanapaenis G.D. Carr -- accepted -- Maui dubautia
  Dubautia X demissifolia (Sherff) D.D. Keck (pro sp.) -- accepted -- dubautia
  Dubautia X fallax Sherff -- accepted -- dubautia
  Dubautia X fucosa Sherff -- not accepted
  Dubautia X media Sherff -- accepted -- dubautia
  Dubautia X mendacoides O. Deg. & Sherff -- not accepted
  Dubautia X mendax Sherff -- not accepted
  Dubautia X molokaiensis (Hillebr.) D.D. Keck (pro sp.) -- accepted -- Molokai dubautia
  Dubautia X montana (H. Mann) D.D. Keck (pro sp.) -- accepted -- dubautia
  Dubautia X paludicola Sherff -- not accepted
  Dubautia X thyrsiflora (Sherff) D.D. Keck (pro sp.) -- accepted -- dubautia
  Dugaldia grandiflora Rydb. -- not accepted
  Dugaldia hoopesii (A. Gray) Rydb. -- not accepted
  Dysodiopsis (A. Gray) Rydb. -- accepted -- dogfennel
  Dysodiopsis tagetoides (Torr. & A. Gray) Rydb. -- accepted -- false dogfennel, marygold dogweed
  Dysodium divaricatum Rich. -- not accepted
  Dyssodia Cav. -- accepted -- dyssodia, dogweed
  Dyssodia acerosa DC. -- not accepted
  Dyssodia aurea (A. Gray) A. Nelson -- not accepted
  Dyssodia aurea var. polychaeta (A. Gray) M.C. Johnst. -- not accepted
  Dyssodia belenidium (DC.) Macloskie -- not accepted
  Dyssodia concinna (A. Gray) B.L. Rob. -- not accepted
  Dyssodia cooperi A. Gray -- not accepted
  Dyssodia hartwegii (A. Gray) B.L. Rob. -- not accepted
  Dyssodia micropoides (DC.) Loes. -- not accepted
  Dyssodia neomexicana (A. Gray) B.L. Rob. -- not accepted
  Dyssodia papposa (Vent.) Hitchc. -- accepted -- fetid marigold, dogweed, dogbane dyssodia, fetid-marigold, prairie dogweed, fetid dogweed
  Dyssodia pentachaeta (DC.) B.L. Rob. -- not accepted
  Dyssodia pentachaeta ssp. hartwegii (A. Gray) Strother -- not accepted
  Dyssodia pentachaeta var. belenidium (DC.) Strother -- not accepted
  Dyssodia pentachaeta var. hartwegii (A. Gray) Strother -- not accepted
  Dyssodia pentachaeta var. puberula (Rydb.) Strother -- not accepted
  Dyssodia polychaeta (A. Gray) B.L. Rob. -- not accepted
  Dyssodia porophylla (Cav.) Cav. -- not accepted
  Dyssodia porophylloides A. Gray -- not accepted
  Dyssodia setifolia (Lag.) B.L. Rob. -- not accepted
  Dyssodia setifolia var. greggii (A. Gray) M.C. Johnst. -- not accepted
  Dyssodia setifolia var. radiata (A. Gray) Strother -- not accepted
  Dyssodia tagetoides Torr. & A. Gray -- not accepted
  Dyssodia tenuiloba (DC.) B.L. Rob. -- not accepted
  Dyssodia tenuiloba ssp. wrightii (A. Gray) Strother -- not accepted
  Dyssodia tenuiloba var. texana (Cory) Strother -- not accepted
  Dyssodia tenuiloba var. treculii (A. Gray) Strother -- not accepted
  Dyssodia tephroleuca S.F. Blake -- not accepted -- ashy dogweed
  Dyssodia texana Cory -- not accepted
  Dyssodia thurberi (A. Gray) B.L. Rob. -- not accepted
  Dyssodia treculii (A. Gray) B.L. Rob. -- not accepted
  Dyssodia wrightii (A. Gray) B.L. Rob. -- not accepted
  Eastwoodia Brandegee -- accepted -- eastwoodia
  Eastwoodia elegans Brandegee -- accepted -- yellow aster
  Eatonella A. Gray -- accepted -- eatonella
  Eatonella congdonii A. Gray -- not accepted
  Eatonella nivea (D.C. Eaton) A. Gray -- accepted -- white false tickhead, white eatonella
  Echinacea Moench -- accepted -- purple coneflower
  Echinacea angustifolia DC. -- accepted -- blacksamson echinacea, blacksamson
  Echinacea angustifolia var. angustifolia DC. -- not accepted -- blacksamson echinacea, blacksamson
  Echinacea angustifolia var. strigosa R.L. McGregor -- not accepted -- strigose blacksamson
  Echinacea angustifolia var. tennesseensis (Beadle) S.F. Blake -- not accepted
  Echinacea atrorubens Nutt. -- accepted -- Topeka purple coneflower, yellowsampson
  Echinacea atrorubens var. paradoxa (J.B.S. Norton) Cronquist -- not accepted
  Echinacea laevigata (C.L. Boynt. & Beadle) S.F. Blake -- accepted -- smooth purple coneflower, smooth coneflower
  Echinacea pallida (Nutt.) Nutt. -- accepted -- pale purple coneflower, pale echinacea, purple coneflower
  Echinacea pallida var. angustifolia (DC.) Cronquist -- not accepted
  Echinacea pallida var. sanguinea (Nutt.) Gandhi & R.D. Thomas -- not accepted
  Echinacea pallida var. strigosa (R.L. McGregor) Gandhi -- not accepted
  Echinacea paradoxa (J.B.S. Norton) Britton -- accepted -- Bush's purple coneflower
  Echinacea paradoxa var. neglecta R.L. McGregor -- accepted -- Bush's purple coneflower
  Echinacea paradoxa var. paradoxa (J.B.S. Norton) Britton -- accepted -- Bush's purple coneflower
  Echinacea purpurea (L.) Moench -- accepted -- eastern purple coneflower, purple coneflower
  Echinacea purpurea var. arkansana Steyerm. -- not accepted
  Echinacea purpurea var. laevigata (C.L. Boynt. & Beadle) Cronquist -- not accepted
  Echinacea sanguinea Nutt. -- accepted -- sanguin purple coneflower
  Echinacea simulata R.L. McGregor -- accepted -- wavyleaf purple coneflower
  Echinacea tennesseensis (Beadle) Small -- accepted -- Tennessee purple coneflower
  Echinops L. -- accepted -- globethistle
  Echinops bannaticus Rochel ex Schrad. -- accepted
  Echinops commutatus Jur. -- not accepted
  Echinops exaltatus Schrad. -- accepted -- tall globethistle
  Echinops fruticosus L. -- not accepted
  Echinops rito L. -- not accepted -- southern globethistle
  Echinops rito ssp. rito L. -- not accepted
  Echinops ritro L. -- accepted -- southern globethistle
  Echinops ritro ssp. ritro L. -- accepted
  Echinops ritro ssp. ruthenicus (M. Bieb.) Nyman -- accepted -- southern globethistle
  Echinops ruthenicus M. Bieb. -- not accepted
  Echinops sphaerocephalus L. -- accepted -- great globethistle
  Eclipta L. -- accepted -- eclipta
  Eclipta alba (L.) Hassk. -- not accepted
  Eclipta erecta L. -- not accepted
  Eclipta prostrata (L.) L. -- accepted -- false daisy, eclipta, yerba de tago, yerba de tajo
  Egletes Cass. -- accepted -- tropic daisy, egletes
  Egletes prostrata (Sw.) Kuntze -- accepted -- prostrate tropic daisy, bouton blanc
  Egletes viscosa (L.) Less. -- accepted -- erect tropical daisy
  Elephantopus L. -- accepted -- elephantsfoot
  Elephantopus angustifolius Sw. -- accepted -- narrowleaf elephantsfoot
  Elephantopus carolinianus Raeusch. -- accepted -- Carolina elephantsfoot, leafy elephantfoot
  Elephantopus carolinianus var. simplex Nutt. -- not accepted
  Elephantopus elatus Bertol. -- accepted -- tall elephantsfoot
  Elephantopus elatus var. intermedius Gleason -- not accepted
  Elephantopus flexuosus Raf. -- not accepted
  Elephantopus hypomalacus S.F. Blake -- not accepted
  Elephantopus martii Graham -- not accepted
  Elephantopus mollis Kunth -- accepted -- soft elephantsfoot, elephantopus, cucha-cara, lengua de vaca, yerba de caballo
  Elephantopus nudatus A. Gray -- accepted -- smooth elephantsfoot, naked elephantfoot
  Elephantopus nudicaulis Poir. -- not accepted
  Elephantopus pilosus Philipson -- not accepted
  Elephantopus scaber L. -- accepted
  Elephantopus spicatus Juss. ex Aubl. -- not accepted
  Elephantopus tomentosus L. -- accepted -- devil's grandmother, hairy elephantfoot
  Elephantopus violaceus Sch. Bip. -- not accepted
  Eleutheranthera Poit. ex Bosc -- accepted -- eleutheranthera
  Eleutheranthera ruderalis (Sw.) Sch. Bip. -- accepted -- ogiera
  Emilia Cass. -- accepted -- tasselflower
  Emilia coccinea (Sims) G. Don -- accepted -- scarlet tasselflower
  Emilia fosbergii Nicolson -- accepted -- Florida tasselflower
  Emilia javanica (Burm. f.) C.B. Rob. -- not accepted
  Emilia sonchifolia (L) DC -- accepted -- lilac tasselflower
  Emilia sonchifolia var. javanica (Burm. f.) Mattf. -- not accepted -- lilac tasselflower
  Emilia sonchifolia var. sonchifolia (L) DC -- not accepted -- lilac tasselflower
  Encelia Adans. -- accepted -- brittlebush, encelia
  Encelia actonii Elmer -- accepted -- Acton's brittlebush
  Encelia californica Nutt. -- accepted -- California brittlebush
  Encelia farinosa A. Gray ex Torr. -- accepted -- brittlebush, goldenhills, white brittlebush
  Encelia farinosa var. farinosa A. Gray ex Torr. -- not accepted -- goldenhills
  Encelia farinosa var. phenicodonta (S.F. Blake) I.M. Johnst. -- not accepted -- goldenhills, purple brittlebush
  Encelia farinosa var. radians Brandegee ex S.F. Blake -- not accepted -- goldenhills
  Encelia frutescens (A. Gray) A. Gray -- accepted -- button brittlebush, bush encelia
  Encelia frutescens var. actonii (Elmer) S.F. Blake -- not accepted
  Encelia frutescens var. frutescens (A. Gray) A. Gray -- not accepted -- button brittlebush, bush encelia
  Encelia frutescens var. resinosa M.E. Jones ex S.F. Blake -- not accepted -- button brittlebush, resin brittlebush
  Encelia frutescens var. virginensis (A. Nelson) S.F. Blake -- not accepted
  Encelia microcephala A. Gray -- not accepted
  Encelia nudicaulis A. Gray -- not accepted
  Encelia nutans Eastw. -- accepted -- nodding sunray
  Encelia resinifera C. Clark -- accepted -- sticky brittlebush, button brittlebush
  Encelia resinifera ssp. resinifera C. Clark -- not accepted
  Encelia resinifera ssp. tenuifolia C. Clark -- not accepted
  Encelia scaposa (A. Gray) A. Gray -- accepted -- onehead brittlebush, Scouler's silene
  Encelia scaposa var. stenophylla Shinners -- not accepted
  Encelia virginensis A. Nelson -- accepted -- Virgin River brittlebush, Virgin River encelia
  Encelia virginensis ssp. actonii (Elmer) D.D. Keck -- not accepted
  Encelia virginensis var. actonii (Elmer) B.L. Turner -- not accepted -- Acton's brittlebush
  Encelia virginensis var. virginensis A. Nelson -- not accepted -- Virgin River brittlebush, Virgin River encelia
  Enceliopsis (A. Gray) A. Nelson -- accepted -- sunray
  Enceliopsis argophylla (D.C. Eaton) A. Nelson -- accepted -- silverleaf sunray, silver-leaf sunray
  Enceliopsis argophylla var. grandiflora Jeps. -- not accepted
  Enceliopsis covillei (A. Nelson) S.F. Blake -- accepted -- Panamint daisy
  Enceliopsis nudicaulis (A. Gray) A. Nelson -- accepted -- nakedstem sunray
  Enceliopsis nudicaulis var. corrugata Cronquist -- not accepted -- Ash Meadows sunray, nakedstem sunray
  Enceliopsis nudicaulis var. nudicaulis (A. Gray) A. Nelson -- not accepted -- nakedstem sunray
  Enceliopsis nutans (Eastw.) A. Nelson -- not accepted -- nodding sunray
  Endorima atropurpurea (Harper) Small -- not accepted
  Endorima uniflora (Nutt.) Raf. -- not accepted
  Engelmannia A. Gray ex Nutt. -- accepted -- Engelmann's daisy, engelmannia
  Engelmannia peristenia (Raf.) Goodman & C.A. Lawson -- accepted -- Engelmann's daisy
  Engelmannia pinnatifida A. Gray ex Nutt. -- not accepted -- Engelmann's daisy
  Enydra Lour. -- accepted -- swampwort
  Enydra sessilis (Sw.) DC. -- accepted -- smallray swampwort
  Epaltes Cass. -- accepted
  Epaltes australis Less. -- accepted
  Erechtites Raf. -- accepted -- burnweed
  Erechtites arguta (A. Rich.) DC. -- not accepted
  Erechtites glomerata (Desf. ex Poir.) DC. -- not accepted -- Australian fireweed, cutleaf burnweed
  Erechtites hieracifolia (L.) Raf. ex DC. -- not accepted -- burnweed
  Erechtites hieraciifolia var. intermedia Fernald -- not accepted
  Erechtites hieraciifolia var. praealta (Raf.) Fernald -- not accepted
  Erechtites hieraciifolius (L.) Raf. ex DC. -- accepted -- American burnweed, burnweed
  Erechtites hieraciifolius var. cacalioides (Fisch. ex Spreng.) Less. ex Griseb. -- not accepted
  Erechtites hieraciifolius var. hieraciifolius (L.) Raf. ex DC. -- accepted -- American burnweed
  Erechtites hieraciifolius var. megalocarpa (Fernald) Cronquist -- accepted -- American burnweed
  Erechtites megalocarpa Fernald -- not accepted
  Erechtites minimus (Poir.) DC. -- accepted -- coastal burnweed
  Erechtites prenanthoides (A. Rich.) DC. -- not accepted
  Erechtites valerianifolia (Link ex Spreng.) DC. -- accepted -- tropical burnweed
  Ericameria Nutt. -- accepted -- goldenbush, heath goldenrod, heathgoldenrod
  Ericameria albida (M.E. Jones ex A. Gray) L.C. Anderson -- accepted -- whiteflower rabbitbrush
  Ericameria arborescens (A. Gray) Greene -- accepted -- goldenfleece
  Ericameria arizonica R.P. Roberts, Urbatsch & J.L. Anderson -- accepted
  Ericameria austrotexana M.C. Johnst. -- not accepted
  Ericameria bloomeri (A. Gray) J.F. Macbr. -- accepted -- rabbitbush, Bloomer's goldenbush
  Ericameria brachylepis (A. Gray) H.M. Hall -- accepted -- chaparral goldenbush
  Ericameria cervina (S. Watson) Rydb. -- accepted -- deer goldenbush, deer heath-goldenrod, deer heathgoldenrod
  Ericameria compacta (H.M. Hall) G.L. Nesom -- accepted -- Charleston Mountain goldenbush, Spring Mountains goldenbush
  Ericameria cooperi (A. Gray) H.M. Hall -- accepted -- Cooper's goldenbush, goldenbush
  Ericameria cooperi var. cooperi (A. Gray) H.M. Hall -- not accepted
  Ericameria crispa (L.C. Anderson) G.L. Nesom -- accepted -- crisped goldenbush
  Ericameria cuneata (A. Gray) McClatchie -- accepted -- cliff goldenbush, cliff heath-goldenrod, cliff heathgoldenrod
  Ericameria cuneata var. cuneata (A. Gray) McClatchie -- accepted -- cliff goldenbush
  Ericameria cuneata var. macrocephala Urbatsch -- accepted -- cliff goldenbush
  Ericameria cuneata var. spathulata (A. Gray) H.M. Hall -- accepted -- cliff goldenbush, cliff heathgoldenrod
  Ericameria depressa (Nutt.) L.C. Anderson -- not accepted
  Ericameria discoidea (Nutt.) G.L. Nesom -- accepted -- whitestem goldenbush
  Ericameria discoidea var. discoidea (Nutt.) G.L. Nesom -- accepted -- whitestem goldenbush, discoid goldenbush
  Ericameria discoidea var. linearis (Rydb.) G.L. Nesom -- not accepted -- whitestem goldenbush
  Ericameria eremobia (L.C. Anderson) L.C. Anders -- not accepted
  Ericameria ericoides (Less.) Jeps. -- accepted -- California goldenbush
  Ericameria fasciculata (Eastw.) J.F. Macbr. -- accepted -- Eastwood's goldenbush
  Ericameria filifolia (Rydb.) L.C. Anderson -- not accepted
  Ericameria gilmanii (S.F. Blake) G.L. Nesom -- accepted -- whiteflower goldenbush
  Ericameria graminea (H.M. Hall) L.C. Anderson -- not accepted
  Ericameria greenei (A. Gray) G.L. Nesom -- accepted -- Greene's goldenbush, slender goldenrod
  Ericameria humilis (Greene) L.C. Anderson -- not accepted
  Ericameria laricifolia (A. Gray) Shinners -- accepted -- turpentine bush, ericameria, turpentinebush
  Ericameria lignumviridis (S.L. Welsh) G.L. Nesom -- accepted -- Greenwood's goldenbush
  Ericameria linearifolia (DC.) Urbatsch & Wussow -- accepted -- narrowleaf goldenbush, slimleaf goldenbush
  Ericameria linearis (Rydb.) R.P. Roberts & Urbatsch -- accepted -- whitestem goldenbush
  Ericameria linifolia (Greene) L.C. Anderson -- not accepted
  Ericameria molesta (S.F. Blake) L.C. Anderson -- not accepted
  Ericameria nana Nutt. -- accepted -- dwarf goldenbush, low goldenbush
  Ericameria nauseosa (Pall. ex Pursh) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush, goldenbush
  Ericameria nauseosa ssp. ammophila L.C. Anderson -- accepted -- machaeranthera
  Ericameria nauseosa ssp. consimilis (Greene) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa ssp. consimilis var. arenaria (L.C. Anderson) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. consimilis var. ceruminosa (Durand & Hilg.) G.L. Nesom & Baird -- not accepted -- threadleaf rabbitbrush
  Ericameria nauseosa ssp. consimilis var. juncea (Greene) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. consimilis var. leiosperma (A. Gray) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. consimilis var. mohavensis (Greene) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. consimilis var. nitida (L.C. Anderson) G.L. Nesom & Baird -- not accepted -- nitid rubber rabbitbrush
  Ericameria nauseosa ssp. consimilis var. oreophila (A. Nelson) G.L. Nesom & Baird -- not accepted -- threadleaf rubber rabbitbrush
  Ericameria nauseosa ssp. consimilis var. turbinata (M.E. Jones) Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa (Pall. ex Pursh) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa ssp. nauseosa var. bernardina (H.M. Hall) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. bigelovii (A. Gray) G.L. Nesom & Baird -- not accepted -- Bigelow rubber rabbitbrush
  Ericameria nauseosa ssp. nauseosa var. glabrata (A. Gray) G.L. Nesom & Baird -- not accepted -- rubber rabbitbrush, green rubber rabbitbrush
  Ericameria nauseosa ssp. nauseosa var. glareosa (M.E. Jones) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. hololeuca (A. Gray) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. iridis (L.C. Anderson) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. latisquamea (A. Gray) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. nana (Cronquist) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. nauseosa (Pall. ex Pursh) G.L. Nesom & Baird -- not accepted -- rubber rabbitbrush
  Ericameria nauseosa ssp. nauseosa var. psilocarpa (S.F. Blake) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. salicifolia (Rydb.) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. speciosa (Nutt.) G.L. Nesom & Baird -- not accepted -- gray rubber rabbitbrush
  Ericameria nauseosa ssp. nauseosa var. texensis (L.C. Anderson) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa ssp. nauseosa var. washoensis (L.C. Anderson) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa var. arenaria (L.C. Anderson) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. arta (A. Nelson) G.L. Nesom & Baird -- not accepted
  Ericameria nauseosa var. bernardina (H.M. Hall) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. bigelovii (A. Gray) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. ceruminosa (Durand & Hilg.) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. glabrata (A. Gray) G.L. Nesom & Baird -- not accepted -- rubber rabbitbrush
  Ericameria nauseosa var. glareosa (M.E. Jones) G.L. Nesom & Baird -- not accepted -- rubber rabbitbrush
  Ericameria nauseosa var. graveolens (Nutt.) Reveal & Schuyler -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. hololeuca (A. Gray) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. iridis (L.C. Anderson) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. juncea (Greene) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. latisquamea (A. Gray) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. leiosperma (A. Gray) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. mohavensis (Greene) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. nana (Cronquist) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. nauseosa (Pall. ex Pursh) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. nitida (L.C. Anderson) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. oreophila (A. Nelson) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. psilocarpa (S.F. Blake) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. salicifolia (Rydb.) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. speciosa (Nutt.) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. texensis (L.C. Anderson) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. turbinata (M.E. Jones) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria nauseosa var. washoensis (L.C. Anderson) G.L. Nesom & Baird -- accepted -- rubber rabbitbrush
  Ericameria obovata (Rydb.) G.L. Nesom -- accepted -- Rydberg's goldenbush
  Ericameria ophitidis (J.T. Howell) G.L. Nesom -- accepted -- serpentine goldenbush
  Ericameria palmeri (A. Gray) H.M. Hall -- accepted -- Palmer's goldenbush
  Ericameria palmeri var. pachylepis (H.M. Hall) G.L. Nesom -- accepted -- Palmer's rabbitbrush
  Ericameria palmeri var. palmeri (A. Gray) H.M. Hall -- accepted -- Palmer's rabbitbrush
  Ericameria paniculata (A. Gray) Rydb. -- accepted -- Mojave rabbitbrush, desert rabbitbrush
  Ericameria parishii (Greene) H.M. Hall -- accepted -- Parish's rabbitbrush, goldenbush
  Ericameria parishii var. parishii (Greene) H.M. Hall -- not accepted
  Ericameria parryi (A. Gray) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush, Parry's goldenbush
  Ericameria parryi var. affinis (A. Nelson) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. aspera (Greene) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. attenuata (M.E. Jones) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. howardii (Parry ex A. Gray) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. imula (H.M. Hall & Clem.) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. latior (H.M. Hall & Clem.) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. monocephala (A. Nelson & Kennedy) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. montana (L.C. Anderson) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. nevadensis (A. Gray) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. parryi (A. Gray) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush, green rabbitbrush
  Ericameria parryi var. salmonensis (L.C. Anderson) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria parryi var. vulcanica (Greene) G.L. Nesom & Baird -- accepted -- Parry's rabbitbrush
  Ericameria pinifolia (A. Gray) H.M. Hall -- accepted -- pinebush
  Ericameria pulchella (A. Gray) L.C. Anderson -- not accepted
  Ericameria pulchella ssp. baileyi (Woot. & Standl.) L.C. Anderson -- not accepted
  Ericameria pulchella var. elatior (Standl.) L.C. Anderson -- not accepted
  Ericameria resinosa Nutt. -- accepted -- Columbian goldenbush
  Ericameria spathulata (L.C. Anderson) L.C. Anderson -- not accepted
  Ericameria suffruticosa (Nutt.) G.L. Nesom -- accepted -- singlehead goldenbush, single-head heath-goldenrod, bighead goldenbush
  Ericameria teretifolia (Durand & Hilg.) Jeps. -- accepted -- green rabbitbrush, needle-leaf rabbitbrush, needleleaf rabbitbrush
  Ericameria triantha (S.F. Blake) Shinners -- not accepted
  Ericameria vaseyi (A. Gray) L.C. Anderson -- not accepted
  Ericameria viscidiflora (Hook.) L.C. Anderson -- not accepted
  Ericameria viscidiflora ssp. axillaris (D.D. Keck) L.C. Anderson -- not accepted
  Ericameria viscidiflora ssp. lanceolata (Nutt.) L.C. Anderson -- not accepted
  Ericameria viscidiflora ssp. planifolia (L.C. Anderson) L.C. Anderson -- not accepted
  Ericameria viscidiflora ssp. puberula (D.C. Eaton) L.C. Anderson -- not accepted
  Ericameria viscidiflora var. latifolia (D.C. Eaton) L.C. Anderson -- not accepted
  Ericameria viscidiflora var. stenophylla (A. Gray) L.C. Anderson -- not accepted
  Ericameria watsonii (A. Gray) G.L. Nesom -- accepted -- Watson's goldenbush, Watson's heath-goldenrod
  Ericameria winwardii (Dorn & Delmatier) R.P. Roberts & Urbatsch -- accepted -- Winward's goldenbrush
  Ericameria X bolanderi (A. Gray) G.L. Nesom & Baird -- accepted
  Ericameria X uintahensis (L.C. Anderson) G.L. Nesom & Baird -- accepted -- Uinta rubber rabbitbrush
  Ericameria X viscosa (D.D. Keck) G.L. Nesom & Baird -- accepted
  Ericameria zionis (L.C. Anderson) G.L. Nesom -- accepted -- subalpine goldenbush
  Erigeron L. -- accepted -- fleabane, vergerettes, daisy
  Erigeron abajoensis Cronquist -- accepted -- Abajo fleabane, Awapa fleabane
  Erigeron acomanus Spellenb. & P. Knight -- accepted -- bluewater fleabane
  Erigeron acris L. -- accepted -- bitter fleabane, bitter daisy, blue fleabane
  Erigeron acris auct. non L. -- not accepted
  Erigeron acris ssp. acris L. -- not accepted
  Erigeron acris ssp. debilis (A. Gray) Piper -- not accepted -- bitter fleabane
  Erigeron acris ssp. decoloratus (H. Lindb.) Hiitonen -- accepted
  Erigeron acris ssp. droebachiensis (O.F. Müll.) Arcang. -- accepted
  Erigeron acris ssp. kamtschaticus (DC.) H. Hara -- not accepted -- bitter fleabane
  Erigeron acris ssp. politus (Fr.) Schinz & R. Keller -- not accepted -- bitter fleabane
  Erigeron acris var. acris L. -- accepted
  Erigeron acris var. asteroides (Andrz. ex Besser) DC. -- not accepted
  Erigeron acris var. debilis A. Gray -- not accepted
  Erigeron acris var. elatus (Hook.) Cronquist -- not accepted
  Erigeron acris var. kamtschaticus (DC.) Herder -- accepted -- bitter fleabane, bitter daisy, blue fleabane
  Erigeron aequifolius H.M. Hall -- accepted -- Hall's fleabane
  Erigeron alaskanus Cronquist -- not accepted
  Erigeron algidus Jeps. -- accepted -- stalked fleabane, Sierra daisy
  Erigeron aliceae Howell -- accepted -- Alice Eastwood's fleabane
  Erigeron allocotus S.F. Blake -- accepted -- Big Horn fleabane
  Erigeron alpiniformis Cronquist -- accepted -- alpine fleabane, boreal fleabane
  Erigeron alpinus L. -- accepted
  Erigeron alpinus ssp. intermedius (Schleich.) Pawl. -- accepted
  Erigeron alpinus var. elatus Hook. -- not accepted
  Erigeron anchana G.L. Nesom -- accepted -- Sierra Ancha fleabane
  Erigeron andersonii A. Gray -- not accepted
  Erigeron angulosus ssp. debilis (A. Gray) Piper -- not accepted
  Erigeron angustatus Greene -- not accepted -- serpentine fleabane
  Erigeron annuus (L.) Pers. -- accepted -- eastern daisy fleabane, annual fleabane
  Erigeron annuus ssp. strigosus (Muhl. ex Willd.) Wagenitz -- not accepted
  Erigeron annuus var. discoideus (Victorin & Rouss.) Cronquist -- not accepted
  Erigeron anodonta Lunell -- not accepted
  Erigeron aphanactis (A. Gray) Greene -- accepted -- rayless shaggy fleabane, beach daisy
  Erigeron aphanactis var. aphanactis (A. Gray) Greene -- accepted -- rayless shaggy fleabane, rayless shaggy daisy
  Erigeron aphanactis var. congestus (Greene) Cronquist -- accepted -- rayless shaggy fleabane, rayless shaggy daisy
  Erigeron apurensis (Kunth) Griseb. -- not accepted
  Erigeron arenarioides (D.C. Eaton ex A. Gray) A. Gray ex Rydb. -- accepted -- sand fleabane
  Erigeron arenarius Greene -- not accepted
  Erigeron argentatus A. Gray -- accepted -- silver fleabane, silvery daisy
  Erigeron arisolius G.L. Nesom -- accepted -- arid throne fleabane
  Erigeron arizonicus A. Gray -- accepted -- Arizona fleabane
  Erigeron asper Nutt. -- not accepted -- rough fleabane
  Erigeron asperugineus (D.C. Eaton) A. Gray -- accepted -- Idaho fleabane, Idaho daisy
  Erigeron asperum Nutt. -- not accepted
  Erigeron asperum var. pubescens (Hook.) Breitung -- not accepted
  Erigeron atticus Vill. -- accepted
  Erigeron aurantiacus Regel -- accepted -- orange daisy, orange fleabane
  Erigeron aureus Greene -- accepted -- alpine yellow fleabane
  Erigeron aureus var. aureus Greene -- not accepted -- alpine yellow fleabane
  Erigeron austiniae Greene -- not accepted -- sagebrush fleabane, dwarf yellow daisy
  Erigeron awapensis S.L. Welsh -- not accepted -- Awapa fleabane
  Erigeron barbellulatus Greene -- accepted -- shining fleabane
  Erigeron basalticus Hoover -- accepted -- basalt fleabane, basalt daisy
  Erigeron bellidiastrum Nutt. -- accepted -- western daisy fleabane, western fleabane
  Erigeron bellidiastrum var. arenarius (Greene) G.L. Nesom -- accepted -- sandwort daisy fleabane
  Erigeron bellidiastrum var. bellidiastrum Nutt. -- accepted -- western daisy fleabane
  Erigeron bellidiastrum var. robustus Cronquist -- accepted -- western daisy fleabane
  Erigeron bellidifolius Muhl. ex Willd. -- not accepted
  Erigeron bellioides DC. -- accepted -- bellorita
  Erigeron bigelovii A. Gray -- accepted -- Bigelow's fleabane
  Erigeron bilboanus (Remy) Cabrera -- not accepted
  Erigeron biolettii Greene -- accepted -- Biolett's erigeron
  Erigeron bistiensis G.L. Nesom & Hevron -- not accepted -- Ojo Alamo fleabane
  Erigeron blochmaniae Greene -- accepted -- Blochman's erigeron
  Erigeron bloomeri A. Gray -- accepted -- scabland fleabane, Bloomer's daisy
  Erigeron bloomeri var. bloomeri A. Gray -- accepted -- scabland fleabane, scabland daisy
  Erigeron bloomeri var. nudatus (A. Gray) Cronquist -- accepted -- scabland fleabane
  Erigeron bloomeri var. pubens D.D. Keck -- not accepted -- scabland fleabane
  Erigeron bloomeri var. typicus Cronquist -- not accepted
  Erigeron bonariensis L. -- not accepted
  Erigeron borealis (Vierh.) Simms -- not accepted -- boreal fleabane
  Erigeron brandegeei A. Gray -- not accepted
  Erigeron breweri A. Gray -- accepted -- Brewer's fleabane, Brewer's daisy
  Erigeron breweri var. bisanctus G.L. Nesom -- accepted -- Brewer's erigeron
  Erigeron breweri var. breweri A. Gray -- accepted -- Brewer's fleabane, Brewer's daisy
  Erigeron breweri var. covillei (Greene) G.L. Nesom -- accepted -- Coville's erigeron
  Erigeron breweri var. elmeri Greene -- not accepted
  Erigeron breweri var. jacinteus (H.M. Hall) Cronquist -- accepted -- Brewer's fleabane
  Erigeron breweri var. klamathensis G.L. Nesom -- not accepted -- Klamath erigeron
  Erigeron breweri var. porphyreticus (M.E. Jones) Cronquist -- accepted -- Brewer's fleabane, Brewer's daisy
  Erigeron caespitosus Nutt. -- accepted -- tufted fleabane
  Erigeron caespitosus var. laccoliticus M.E. Jones -- not accepted
  Erigeron callianthemus Greene -- not accepted
  Erigeron calvus Coville -- accepted -- bald fleabane
  Erigeron canaani S.L. Welsh -- accepted -- Abajo fleabane
  Erigeron canadensis L. -- not accepted
  Erigeron canadensis var. glabratus A. Gray -- not accepted
  Erigeron canadensis var. pusillus (Nutt.) B. Boivin, non H.E. Ahles -- not accepted
  Erigeron candidus Widder -- accepted
  Erigeron canus A. Gray -- accepted -- hoary fleabane
  Erigeron carringtoniae S.L. Welsh -- not accepted -- Sanpete County fleabane
  Erigeron cascadensis A. Heller -- accepted -- Cascade fleabane
  Erigeron caucasicus Steven -- accepted
  Erigeron caucasicus ssp. venustus (Botsch.) Grierson -- accepted
  Erigeron cavernensis S.L. Welsh & N.D. Atwood -- accepted -- lone fleabane
  Erigeron cervinus Greene -- accepted -- Siskiyou fleabane
  Erigeron chinensis Jacq. -- not accepted
  Erigeron chrysopsidis A. Gray -- accepted -- dwarf yellow fleabane
  Erigeron chrysopsidis ssp. austinae (Greene) Cronquist -- not accepted
  Erigeron chrysopsidis ssp. austiniae (Greene) Cronquist -- not accepted
  Erigeron chrysopsidis ssp. chrysopsidis A. Gray -- not accepted -- dwarf yellow fleabane
  Erigeron chrysopsidis var. austiniae (Greene) G.L. Nesom -- accepted -- sagebrush fleabane
  Erigeron chrysopsidis var. brevifolius Piper -- accepted -- dwarf yellow fleabane
  Erigeron chrysopsidis var. chrysopsidis A. Gray -- accepted -- dwarf yellow fleabane
  Erigeron clokeyi Cronquist -- accepted -- Clokey's fleabane, Clokey's daisy
  Erigeron clokeyi var. clokeyi Cronquist -- accepted -- Clokey's fleabane
  Erigeron clokeyi var. pinzliae G.L. Nesom -- accepted -- Clokey's fleabane
  Erigeron colomexicanus A. Nelson -- not accepted -- running fleabane, running daisy
  Erigeron compactus S.F. Blake -- accepted -- cushion daisy, fernleaf fleabane, fern-leaf fleabane
  Erigeron compactus var. consimilis (Cronquist) S.F. Blake -- not accepted
  Erigeron compositus Pursh -- accepted -- cutleaf daisy, dwarf mountain fleabane, vergerette ŕ feuilles segmentées, fernleaf fleabane
  Erigeron compositus var. compositus Pursh -- not accepted -- dwarf mountain fleabane
  Erigeron compositus var. discoideus A. Gray -- not accepted
  Erigeron compositus var. glabratus Macoun -- not accepted
  Erigeron compositus var. multifidus (Rydb.) J.F. Macbr. & Payson -- not accepted
  Erigeron compositus var. pinnatisectus A. Gray -- not accepted
  Erigeron compositus var. typicus Hook. -- not accepted
  Erigeron concinnus (Hook. & Arn.) Torr. & A. Gray -- accepted -- Navajo fleabane, hairy daisy
  Erigeron concinnus var. aphanactis A. Gray -- not accepted
  Erigeron concinnus var. concinnus (Hook. & Arn.) Torr. & A. Gray -- accepted -- Navajo fleabane, Navajo daisy
  Erigeron concinnus var. condensatus D.C. Eaton -- accepted -- Navajo fleabane, Navajo daisy
  Erigeron concinnus var. subglaber (Cronquist) G.L. Nesom -- accepted -- Navajo fleabane, Lake Powell fleabane
  Erigeron condensatus (D.C. Eaton) Greene -- not accepted
  Erigeron consimilis Cronquist -- accepted -- foothill fleabane
  Erigeron conspicuus Rydb. -- not accepted
  Erigeron controversus Greene -- not accepted
  Erigeron corymbosus Nutt. -- accepted -- longleaf fleabane
  Erigeron coulteri Porter -- accepted -- large mountain fleabane, Coulter's fleabane, whiteray daisy
  Erigeron crispus Pourr. -- not accepted
  Erigeron cronquistii Maguire -- accepted -- Cronquist's fleabane
  Erigeron cuneifolius DC. -- accepted -- wedgeleaf fleabane
  Erigeron davisii (Cronquist) G.L. Nesom -- accepted -- Davis' fleabane
  Erigeron debilis (A. Gray) Rydb. -- not accepted
  Erigeron decumbens Nutt. -- accepted -- Willamette fleabane
  Erigeron decumbens ssp. robustior Cronquist -- not accepted
  Erigeron decumbens var. decumbens Nutt. -- accepted -- Willamette fleabane, Willamette daisy
  Erigeron decumbens var. robustior (Cronquist) Cronquist -- not accepted -- Willamette fleabane
  Erigeron delicatus Cronquist -- not accepted
  Erigeron delphiniifolius ssp. neomexicanus (A. Gray) Cronquist -- not accepted
  Erigeron delphiniifolius var. euneomexicanus Cronquist -- not accepted
  Erigeron delphiniifolius var. oreophilus (Greenm.) Cronquist -- not accepted
  Erigeron denalii A. Nelson -- accepted -- Mex's fleabane
  Erigeron disparipilus Cronquist -- accepted -- white cushion fleabane
  Erigeron divaricatus Michx. -- not accepted
  Erigeron divergens Torr. & A. Gray -- accepted -- spreading fleabane, spreading daisy
  Erigeron divergens var. cinereus A. Gray -- not accepted
  Erigeron divergens var. typicus Cronquist -- not accepted
  Erigeron droebachensis O.F. Müll. ex Retz. -- accepted
  Erigeron eatonii A. Gray -- accepted -- Eaton's fleabane, Eaton's daisy
  Erigeron eatonii ssp. plantagineus (Greene) Cronquist -- not accepted
  Erigeron eatonii ssp. typicus Cronquist -- not accepted
  Erigeron eatonii ssp. villosus Cronquist -- not accepted
  Erigeron eatonii var. eatonii A. Gray -- accepted -- Eaton's fleabane, Eaton's daisy
  Erigeron eatonii var. lavandulus Strother & Ferlatte -- accepted -- Eaton's fleabane
  Erigeron eatonii var. nevadincola (S.F. Blake) G.L. Nesom -- accepted -- Eaton's fleabane
  Erigeron eatonii var. plantagineus (Greene) Cronquist -- accepted -- Eaton's fleabane, Eaton's daisy
  Erigeron eatonii var. sonnei (Greene) G.L. Nesom -- accepted -- Eaton's fleabane
  Erigeron eatonii var. villosus (Cronquist) Cronquist -- accepted -- Eaton's fleabane
  Erigeron elatior (A. Gray) Greene -- accepted -- tall fleabane
  Erigeron elatus (Hook.) Greene -- accepted -- swamp boreal-daisy
  Erigeron elatus var. oligocephalus (Fernald & Wiegand) Fernald -- not accepted
  Erigeron elegantulus Greene -- accepted -- blue dwarf fleabane
  Erigeron elmeri (Greene) Greene -- accepted -- Elmer's erigeron
  Erigeron elongatus Ledeb. -- accepted
  Erigeron engelmannii A. Nelson -- accepted -- Engelmann's fleabane, Engelmann's daisy
  Erigeron engelmannii ssp. davisii Cronquist -- not accepted
  Erigeron engelmannii ssp. typicus Cronquist -- not accepted
  Erigeron engelmannii var. davisii (Cronquist) Cronquist -- not accepted -- Davis' fleabane
  Erigeron engelmannii var. engelmannii A. Nelson -- not accepted -- Engelmann's fleabane
  Erigeron eriocephalus J. Vahl -- not accepted
  Erigeron eriophyllus A. Gray -- not accepted
  Erigeron evermannii Rydb. -- accepted -- Evermann's fleabane
  Erigeron eximius Greene -- accepted -- sprucefir fleabane, spruce-fir fleabane
  Erigeron filifolius (Hook.) Nutt. -- accepted -- threadleaf fleabane, threadleaf daisy
  Erigeron filifolius var. filifolius (Hook.) Nutt. -- not accepted -- threadleaf fleabane, threadleaf daisy
  Erigeron filifolius var. robustior M. Peck -- not accepted -- threadleaf fleabane
  Erigeron filifolius var. typicus Cronquist -- not accepted
  Erigeron flabellifolius Rydb. -- accepted -- fanleaf fleabane
  Erigeron flagellaris A. Gray -- accepted -- trailing fleabane, trailing daisy
  Erigeron flagellaris var. trilobatus Maguire ex Cronquist -- not accepted
  Erigeron flagellaris var. typicus Cronquist -- not accepted
  Erigeron flettii G.N. Jones -- accepted -- Flett's fleabane
  Erigeron flexuosus Cronquist -- not accepted
  Erigeron floribundus (Kunth) Sch. Bip. -- not accepted
  Erigeron foliosus Nutt. -- accepted -- leafy fleabane
  Erigeron foliosus var. blochmaniae (Greene) H.M. Hall -- not accepted
  Erigeron foliosus var. confinis (Howell) Jeps. -- accepted -- leafy fleabane
  Erigeron foliosus var. covillei (Greene) Compton -- not accepted
  Erigeron foliosus var. foliosus Nutt. -- accepted -- leafy fleabane
  Erigeron foliosus var. franciscensis G.L. Nesom -- accepted -- Franciscan erigeron
  Erigeron foliosus var. hartwegii (Greene) Jeps. -- accepted -- Hartweg's fleabane
  Erigeron foliosus var. mendocinus (Greene) G.L. Nesom -- accepted -- Mendocino erigeron
  Erigeron foliosus var. stenophyllus (Nutt.) A. Gray -- not accepted
  Erigeron formosissimus Greene -- accepted -- beautiful fleabane
  Erigeron formosissimus var. formosissimus Greene -- not accepted -- beautiful fleabane
  Erigeron formosissimus var. typicus Cronquist -- not accepted
  Erigeron formosissimus var. viscidus (Rydb.) Cronquist -- not accepted -- beautiful fleabane
  Erigeron garrettii A. Nelson -- accepted -- Garrett's fleabane
  Erigeron gaudinii Brugger -- accepted
  Erigeron geiseri Shinners -- accepted -- Geiser's fleabane, basin fleabane
  Erigeron geiseri var. calcicola Shinners -- not accepted
  Erigeron gilensis Woot. & Standl. -- not accepted -- Gila fleabane
  Erigeron glabellus Nutt. -- accepted -- streamside fleabane, smooth fleabane
  Erigeron glabellus ssp. pubescens (Hook.) Cronquist -- not accepted
  Erigeron glabellus ssp. typicus Cronquist -- not accepted
  Erigeron glabellus var. glabellus Nutt. -- accepted -- streamside fleabane, rough fleabane
  Erigeron glabellus var. mollis A. Gray -- not accepted
  Erigeron glabellus var. pubescens Hook. -- accepted -- streamside fleabane, fleabane
  Erigeron glabellus var. viscidus (Rydb.) B. Boivin -- not accepted
  Erigeron glabellus var. yukonensis (Rydb.) Hultén -- not accepted
  Erigeron glabratus Hoppe & Hornsch. ex Bluff & Fingerh. -- accepted
  Erigeron glacialis (Nutt.) A. Nelson -- accepted -- subalpine fleabane
  Erigeron glacialis var. glacialis (Nutt.) A. Nelson -- accepted -- subalpine fleabane
  Erigeron glacialis var. hirsutus (Cronquist) G.L. Nesom -- accepted -- subalpine fleabane
  Erigeron glaucus Ker Gawl. -- accepted -- seaside fleabane
  Erigeron goodrichii S.L. Welsh -- accepted -- Uinta Mountain fleabane
  Erigeron gracilis Rydb. -- accepted -- quill fleabane
  Erigeron grandiflorus Hook. -- accepted -- largeflower fleabane, onestem fleabane
  Erigeron grandiflorus ssp. arcticus A.E. Porsild -- not accepted -- largeflower fleabane
  Erigeron grandiflorus ssp. grandiflorus Hook. -- not accepted -- largeflower fleabane
  Erigeron grandiflorus ssp. muirii (A. Gray) Hultén -- not accepted
  Erigeron grandiflorus var. elatior A. Gray -- not accepted
  Erigeron greenei G.L. Nesom -- accepted -- serpentine fleabane
  Erigeron heliographis G.L. Nesom -- accepted -- Heliograph Peak fleabane
  Erigeron hessii G.L. Nesom -- accepted -- Hess' fleabane
  Erigeron howellii A. Gray -- accepted -- Howell's fleabane
  Erigeron huberi S.L. Welsh & N.D. Atwood -- not accepted
  Erigeron hultenii Spongberg -- accepted -- Hulten's fleabane
  Erigeron humilis Graham -- accepted -- arctic alpine fleabane
  Erigeron hyperboreus Greene -- accepted -- tundra fleabane
  Erigeron hyssopifolius Michx. -- accepted -- hyssopleaf fleabane
  Erigeron hyssopifolius var. hyssopifolius Michx. -- not accepted -- hyssopleaf fleabane
  Erigeron hyssopifolius var. villicaulis Fernald -- not accepted -- vergerette ŕ feuilles d'hysope variété ŕ tige velue, hyssopleaf fleabane
  Erigeron inornatus (A. Gray) A. Gray -- accepted -- California rayless fleabane, rayless daisy
  Erigeron inornatus var. angustatus A. Gray -- not accepted
  Erigeron inornatus var. biolettii (Greene) Jeps. -- not accepted
  Erigeron inornatus var. calidipetris G.L. Nesom -- accepted -- California rayless fleabane
  Erigeron inornatus var. inornatus (A. Gray) A. Gray -- accepted -- California rayless fleabane, California rayless daisy
  Erigeron inornatus var. keilii G.L. Nesom -- accepted -- Keil's erigeron
  Erigeron inornatus var. reductus Cronquist -- not accepted
  Erigeron inornatus var. viscidulus A. Gray -- not accepted
  Erigeron jamaicensis L. -- accepted -- Jamaican fleabane
  Erigeron jonesii Cronquist -- accepted -- Jones' fleabane, Jones' daisy
  Erigeron jucundus Greene -- not accepted
  Erigeron kachinensis S.L. Welsh & Glen Moore -- accepted -- kachina fleabane
  Erigeron kamtschaticus DC. -- not accepted
  Erigeron karvinskianus DC. -- accepted -- Latin American fleabane
  Erigeron klamathensis (G.L. Nesom) G.L. Nesom -- accepted -- Klamath erigeron, MacDougal's yellowtops
  Erigeron kuschei Eastw. -- accepted -- Chiricahua fleabane
  Erigeron lackschewitzii G.L. Nesom & W.A. Weber -- accepted -- Lackschewitz's fleabane
  Erigeron lanatus Hook. -- accepted -- woolly fleabane, hairy daisy
  Erigeron lassenianus Greene -- accepted -- Mt. Lassen fleabane
  Erigeron lassenianus var. deficiens Cronquist -- accepted -- Mt. Lassen fleabane
  Erigeron lassenianus var. lassenianus Greene -- accepted -- Mt. Lassen fleabane
  Erigeron latus (A. Nelson & J.F. Macbr.) Cronquist -- accepted -- broad fleabane, broad daisy
  Erigeron leibergii Piper -- accepted -- Leiberg's fleabane
  Erigeron leiomerus A. Gray -- accepted -- rockslide yellow fleabane, glaber daisy
  Erigeron lemmonii A. Gray -- accepted -- Lemmon's fleabane, Lemmon fleabane
  Erigeron linearis (Hook.) Piper -- accepted -- desert yellow fleabane, linearleaf daisy
  Erigeron linearis var. elegantulus (Greene) J.T. Howell -- not accepted
  Erigeron linifolius Willd. -- not accepted
  Erigeron lobatus A. Nelson -- accepted -- lobed fleabane, lobed daisy
  Erigeron lobatus var. warnockii Shinners -- not accepted
  Erigeron lonchophyllus Hook. -- accepted -- shortray fleabane, low-meadow fleabane, vergerette ŕ feuilles fines, short-ray boreal-daisy, shortray boreal daisy, spearleaf daisy
  Erigeron lonchophyllus var. laurentianus Victorin -- not accepted
  Erigeron macranthus Nutt. -- not accepted
  Erigeron maguirei Cronquist -- accepted -- Maguire's fleabane, Maguire daisy
  Erigeron maguirei var. harrisonii S.L. Welsh -- not accepted
  Erigeron maguirei var. maguirei Cronq. -- not accepted -- Maguire's fleabane
  Erigeron mancus Rydb. -- accepted -- depauperate fleabane
  Erigeron maniopotamicus G.L. Nesom & T.W. Nelson -- accepted
  Erigeron mariposanus Congdon -- accepted -- Mariposa erigeron
  Erigeron melanocephalus (A. Nelson) A. Nelson -- accepted -- blackhead fleabane
  Erigeron mendocinus Greene -- not accepted
  Erigeron mexiae K. Becker -- not accepted -- Mex's fleabane
  Erigeron mimegletes Shinners -- not accepted -- Sonoran fleabane
  Erigeron minor (Hook.) Rydb. -- not accepted
  Erigeron miser A. Gray -- accepted -- starved fleabane
  Erigeron modestus A. Gray -- accepted -- plains fleabane
  Erigeron muirii A. Gray -- accepted -- Muir's fleabane
  Erigeron multiceps Greene -- accepted -- Kern River fleabane
  Erigeron multiradiatus (Lindl. ex DC.) Benth. ex C.B. Clarke -- accepted -- Himalayan fleabane
  Erigeron myosotis Pers. -- accepted
  Erigeron myrionactis Small -- not accepted
  Erigeron nanus Nutt. -- accepted -- dwarf fleabane
  Erigeron naudinii (Bonnet) Humbert -- accepted
  Erigeron nauseosus (M.E. Jones) A. Nelson -- accepted -- Marysvale fleabane, Marysvale daisy
  Erigeron nematophyllus Rydb. -- accepted -- needleleaf fleabane
  Erigeron neomexicanus A. Gray -- accepted -- New Mexico fleabane, oakbelt daisy
  Erigeron nevadensis var. sonnei (Greene) Smilty -- not accepted
  Erigeron nevadincola S.F. Blake -- not accepted -- Nevada fleabane
  Erigeron nivalis Nutt. -- accepted -- bitter daisy, bitter fleabane, blue fleabane
  Erigeron nudiflorus Buckley -- not accepted
  Erigeron oblanceolatus Rydb. -- not accepted
  Erigeron ochroleucus Nutt. -- accepted -- buff fleabane
  Erigeron ochroleucus var. ochroleucus Nutt. -- accepted -- buff fleabane
  Erigeron ochroleucus var. scribneri (Canby ex Rydb.) Cronquist -- not accepted -- buff fleabane
  Erigeron oligodontus Lunell -- not accepted
  Erigeron oreganus A. Gray -- accepted -- gorge fleabane
  Erigeron oreophilus Greenm. -- accepted -- chaparral fleabane
  Erigeron orientalis Boiss. -- accepted
  Erigeron ortegae S.F. Blake -- not accepted
  Erigeron ovinus Cronquist -- accepted -- sheep fleabane, sheep daisy
  Erigeron oxyodontus Lunell -- accepted -- fleabane
  Erigeron oxyphyllus Greene -- accepted -- wand fleabane, rush daisy
  Erigeron pallens Cronquist -- accepted -- pale fleabane
  Erigeron parishii A. Gray -- accepted -- Parish's fleabane, Parish's daisy
  Erigeron parryi Canby & Rose -- accepted -- Parry's fleabane
  Erigeron peregrinus (Banks ex Pursh) Greene -- accepted -- wandering fleabane, subalpine fleabane, wandering daisy
  Erigeron peregrinus ssp. callianthemus (Greene) Cronquist -- not accepted -- subalpine fleabane, subalpine daisy
  Erigeron peregrinus ssp. callianthemus var. angustifolius (A. Gray) Cronquist -- not accepted -- subalpine fleabane
  Erigeron peregrinus ssp. callianthemus var. hirsutus Cronquist -- not accepted -- subalpine fleabane, subalpine daisy
  Erigeron peregrinus ssp. callianthemus var. scaposus (Torr. & A. Gray) Cronquist -- not accepted -- subalpine fleabane
  Erigeron peregrinus ssp. peregrinus (Banks ex Pursh) Greene -- accepted -- subalpine fleabane
  Erigeron peregrinus ssp. peregrinus var. dawsonii Greene -- not accepted -- subalpine fleabane
  Erigeron peregrinus var. angustifolius (A. Gray) Cronquist -- not accepted
  Erigeron peregrinus var. callianthemus (Greene) Cronq. -- not accepted -- subalpine fleabane
  Erigeron peregrinus var. dawsonii Greene -- not accepted -- subalpine fleabane
  Erigeron peregrinus var. eucallianthemus Cronquist -- not accepted
  Erigeron peregrinus var. hirsutus Cronquist -- not accepted -- subalpine fleabane
  Erigeron peregrinus var. peregrinus (Banks ex Pursh) Greene -- accepted -- wandering fleabane, subalpine fleabane
  Erigeron peregrinus var. scaposus (Torr. & A. Gray) Cronquist -- not accepted
  Erigeron peregrinus var. thompsonii (S.F. Blake ex J.W. Thompson) Cronquist -- accepted -- subalpine fleabane
  Erigeron perglaber S.F. Blake -- not accepted
  Erigeron petiolaris Greene -- not accepted
  Erigeron petrophilus Greene -- accepted -- rockloving erigeron
  Erigeron petrophilus var. petrophilus Greene -- accepted -- rockloving erigeron
  Erigeron petrophilus var. sierrensis G.L. Nesom -- accepted -- Sierra erigeron
  Erigeron petrophilus var. viscidulus (A. Gray) G.L. Nesom -- accepted -- rockloving erigeron
  Erigeron peucephyllus A. Gray -- not accepted
  Erigeron philadelphicus L. -- accepted -- Philadelphia fleabane, Philadelphia daisy
  Erigeron philadelphicus ssp. provancheri (Victorin & Rouss.) J.K. Morton -- not accepted -- vergerette de Philadelphie sous-espčce de Provancher
  Erigeron philadelphicus var. glaber Henry -- accepted -- Philadelphia fleabane
  Erigeron philadelphicus var. philadelphicus L. -- accepted -- Philadelphia fleabane, Philadelphia daisy
  Erigeron philadelphicus var. provancheri (Victorin & Rouss.) B. Boivin -- accepted -- Philadelphia fleabane
  Erigeron philadelphicus var. scaturicola (Fernald) Fernald -- not accepted
  Erigeron pinnatisectus (A. Gray) A. Nelson -- accepted -- featherleaf fleabane
  Erigeron piperianus Cronquist -- accepted -- Piper's fleabane
  Erigeron piscaticus G.L. Nesom -- accepted -- Fish Creek fleabane
  Erigeron plateauensis Cronquist -- not accepted
  Erigeron platyphyllus Greene -- not accepted
  Erigeron poliospermus A. Gray -- accepted -- purple cushion fleabane
  Erigeron poliospermus var. cereus Cronquist -- accepted -- purple cushion fleabane
  Erigeron poliospermus var. disciformis (Cronquist) G.L. Nesom -- accepted
  Erigeron poliospermus var. poliospermus A. Gray -- accepted -- purple cushion fleabane
  Erigeron poliospermus var. typicus Cronquist -- not accepted
  Erigeron politus Fr. -- accepted
  Erigeron polymorphus Scop. -- accepted
  Erigeron porsildii G.L. Nesom & D.F. Murray -- accepted -- largeflower fleabane
  Erigeron pringlei A. Gray -- accepted -- Pringle's fleabane
  Erigeron procumbens (Houst. ex Mill.) G.L. Nesom -- accepted -- Corpus Christi fleabane
  Erigeron proselyticus G.L. Nesom -- not accepted -- professor's fleabane
  Erigeron provancheri Victorin & Rouss. -- not accepted
  Erigeron pubescens Kunth -- accepted -- hairy fleabane
  Erigeron pulchellus Michx. -- accepted -- robin's plantain, poor robin fleabane
  Erigeron pulchellus var. brauniae Fernald -- accepted -- Braun's erigeron
  Erigeron pulchellus var. pulchellus Michx. -- accepted -- robin's plantain
  Erigeron pulchellus var. tolsteadii Cronquist -- accepted -- Tolstead's erigeron
  Erigeron pulcherrimus A. Heller -- accepted -- basin fleabane, Ojo Alamo fleabane
  Erigeron pulcherrimus var. pulcherrimus A. Heller -- not accepted -- basin fleabane
  Erigeron pulcherrimus var. wyomingia (Rydb.) Cronquist -- not accepted
  Erigeron pumilus Nutt. -- accepted -- shaggy fleabane, low fleabane, low daisy
  Erigeron pumilus ssp. concinnoides Cronquist -- not accepted
  Erigeron pumilus ssp. intermedius Cronquist -- not accepted -- shaggy fleabane, shaggy daisy
  Erigeron pumilus ssp. intermedius var. gracilior Cronquist -- not accepted -- shaggy fleabane, shaggy daisy
  Erigeron pumilus ssp. pumilus Nutt. -- not accepted -- shaggy fleabane
  Erigeron pumilus ssp. typicus Cronquist -- not accepted
  Erigeron pumilus var. concinnus (Hook. & Arn.) Dorn -- not accepted
  Erigeron pumilus var. condensatus (D.C. Eaton) Cronquist -- not accepted
  Erigeron pumilus var. euconcinnoides Cronquist -- not accepted
  Erigeron pumilus var. euintermedius Cronquist -- not accepted
  Erigeron pumilus var. gracilior Cronq. -- not accepted -- shaggy fleabane
  Erigeron pumilus var. intermedius (Cronquist) Cronquist -- accepted -- shaggy fleabane
  Erigeron pumilus var. pumilus Nutt. -- accepted -- shaggy fleabane
  Erigeron pumilus var. subglaber Cronquist -- not accepted
  Erigeron purpuratus Greene -- accepted -- purple fleabane
  Erigeron purpuratus ssp. pallens (Cronquist) G.W. Douglas -- not accepted
  Erigeron purpuratus var. dilatatus Boivin -- not accepted -- purple fleabane
  Erigeron purpuratus var. purpuratus Greene -- not accepted -- purple fleabane
  Erigeron purpureus Aiton -- not accepted
  Erigeron pusillus Nutt. -- not accepted
  Erigeron pygmaeus (A. Gray) Greene -- accepted -- pygmy fleabane, dwarf daisy
  Erigeron quercifolius Lam. -- accepted -- oakleaf fleabane
  Erigeron radicatus Hook. -- accepted -- taproot fleabane, Huber's fleabane, tap-root fleabane
  Erigeron ramosus (Walter) Britton, Sterns & Poggenb. -- not accepted
  Erigeron ramosus var. beyrichii (Fisch. & C.A. Mey.) A. Gray -- not accepted
  Erigeron reductus (Cronquist) G.L. Nesom -- accepted -- lesser California rayless fleabane
  Erigeron reductus var. angustatus (A. Gray) G.L. Nesom -- accepted -- lesser California rayless fleabane
  Erigeron reductus var. reductus (Cronquist) G.L. Nesom -- accepted -- lesser California rayless fleabane
  Erigeron religiosus Cronquist -- accepted -- Clear Creek fleabane
  Erigeron repens A. Gray -- not accepted
  Erigeron rhizomatus Cronquist -- accepted -- rhizome fleabane, Zuni fleabane
  Erigeron robustior (Cronquist) G.L. Nesom -- accepted -- white cushion fleabane, Willamette fleabane
  Erigeron roylei DC. -- accepted
  Erigeron rusbyi A. Gray -- not accepted
  Erigeron rybius G.L. Nesom -- accepted -- royal fleabane
  Erigeron rydbergii Cronquist -- accepted -- Rydberg's fleabane
  Erigeron salishii G.W. Douglas & Packer -- accepted -- Star Peak fleabane
  Erigeron salmonensis S.J. Brunsfeld & G.L. Nesom -- accepted -- Salmon River fleabane
  Erigeron sanctarum S. Watson -- accepted -- saints fleabane
  Erigeron saxatilis G.L. Nesom -- accepted -- rock fleabane
  Erigeron sceptrifer G.L. Nesom -- accepted -- scepterbearing fleabane
  Erigeron schiedeanus Less. -- not accepted
  Erigeron scopulinus G.L. Nesom & Roth -- accepted -- Winn Falls fleabane
  Erigeron scotteri B. Boivin -- not accepted
  Erigeron serpentinus G.L. Nesom -- accepted -- serpentine erigeron
  Erigeron simplex Greene -- not accepted -- onestem fleabane, oneflower fleabane, one-stem fleabane, onestem daisy
  Erigeron sionis Cronquist -- accepted -- Zion fleabane
  Erigeron sionis var. sionis Cronquist -- accepted
  Erigeron sionis var. trilobatus (Maguire ex Cronquist) S.L. Welsh -- accepted -- professor's fleabane
  Erigeron sivinskii G.L. Nesom -- accepted -- Sivinsk's erigeron
  Erigeron sonnei Greene -- not accepted
  Erigeron sparsifolius Eastw. -- accepted -- Utah fleabane
  Erigeron spathulatus Vahl -- not accepted
  Erigeron speciosus (Lindl.) DC. -- accepted -- aspen fleabane, threenerve fleabane, Oregon fleabane, Oregon daisy
  Erigeron speciosus var. conspicuus (Rydb.) Breitung -- not accepted
  Erigeron speciosus var. macranthus (Nutt.) Cronquist -- not accepted -- aspen fleabane, aspen daisy
  Erigeron speciosus var. mollis (A. Gray) S.L. Welsh -- not accepted
  Erigeron speciosus var. speciosus (Lindl.) DC. -- not accepted -- aspen fleabane, aspen daisy
  Erigeron speciosus var. typicus Cronquist -- not accepted
  Erigeron speciosus var. uintahensis (Cronquist) S.L. Welsh -- not accepted
  Erigeron strigosus Muhl. ex Willd. -- accepted -- prairie fleabane, daisy fleabane, rough fleabane
  Erigeron strigosus ssp. septentrionalis (Fernald & Wiegand) Wagenitz -- not accepted
  Erigeron strigosus var. beyrichii (Fisch. & C.A. Mey.) Torr. & A. Gray ex A. Gray -- not accepted -- Beyrich's fleabane
  Erigeron strigosus var. calcicola J. Allison -- accepted
  Erigeron strigosus var. discoideus Robbins ex A. Gray -- not accepted
  Erigeron strigosus var. dolomiticola J. Allison -- accepted
  Erigeron strigosus var. eligulatus Cronquist -- not accepted
  Erigeron strigosus var. septentrionalis (Fernald & Wiegand) Fernald -- accepted -- prairie fleabane
  Erigeron strigosus var. strigosus Muhl. ex Willd. -- accepted -- prairie fleabane, Beyrich's fleabane
  Erigeron strigosus var. typicus Cronquist -- not accepted
  Erigeron subglaber Cronquist -- accepted -- hairless fleabane
  Erigeron subtrinervis Rydb. ex Porter & Britton -- accepted -- threenerve fleabane, three-nerve fleabane, threeveined fleabane
  Erigeron subtrinervis ssp. conspicuus (Rydb.) Cronquist -- not accepted
  Erigeron subtrinervis ssp. typicus Cronquist -- not accepted
  Erigeron subtrinervis var. conspicuus (Rydb.) Cronquist -- not accepted -- threenerve fleabane
  Erigeron subtrinervis var. subtrinervis Rydb. ex Porter & Britton -- not accepted -- threenerve fleabane
  Erigeron superbus Greene ex Rydb. -- not accepted
  Erigeron supplex A. Gray -- accepted -- supple fleabane
  Erigeron tenellus DC. -- accepted -- Rio Grande fleabane
  Erigeron tener (A. Gray) A. Gray -- accepted -- slender fleabane, slender daisy
  Erigeron tenuis Torr. & A. Gray -- accepted -- slenderleaf fleabane, slender fleabane
  Erigeron thunbergii A. Gray -- accepted
  Erigeron thunbergii ssp. glabratus A. Gray -- accepted
  Erigeron thunbergii var. glabratus A. Gray -- not accepted
  Erigeron tracyi Greene -- accepted -- running fleabane
  Erigeron traversii Shinners -- not accepted
  Erigeron trifidus Hook. -- accepted -- Alberta fleabane
  Erigeron tweedyi Canby -- accepted -- Tweedy's fleabane
  Erigeron uintahensis Cronquist -- accepted -- Uinta fleabane
  Erigeron unalaschkensis (DC.) Vierh. -- not accepted
  Erigeron unalaschkensis Less. -- not accepted
  Erigeron uncialis S.F. Blake -- accepted -- lone fleabane, one-inch daisy
  Erigeron uncialis ssp. conjugans (S.F. Blake) Cronquist -- not accepted -- lone fleabane, lone daisy
  Erigeron uncialis ssp. uncialis S.F. Blake -- not accepted -- lone fleabane, lone daisy
  Erigeron uncialis var. conjugans S.F. Blake -- accepted -- lone fleabane
  Erigeron uncialis var. uncialis S.F. Blake -- accepted -- limestone daisy, lone fleabane
  Erigeron uniflorus L. -- accepted -- oneflower fleabane
  Erigeron uniflorus ssp. eriocephalus (J. Vahl) Cronquist -- not accepted -- oneflower fleabane
  Erigeron uniflorus var. eriocephalus (J. Vahl) B. Boivin -- accepted -- oneflower fleabane
  Erigeron uniflorus var. melanocephalus A. Nelson -- not accepted
  Erigeron uniflorus var. unalaschkensis (DC.) Ostenf. -- not accepted
  Erigeron uniflorus var. uniflorus L. -- accepted -- oneflower fleabane
  Erigeron untermannii S.L. Welsh & Goodrich -- accepted -- Indian Canyon fleabane
  Erigeron ursinus D.C. Eaton -- accepted -- Bear River fleabane, bear daisy
  Erigeron utahensis A. Gray -- accepted -- Utah fleabane
  Erigeron utahensis var. sparsifolius (Eastw.) Cronquist -- not accepted -- Utah fleabane
  Erigeron utahensis var. tetrapleuris (A. Gray) Cronquist -- not accepted
  Erigeron utahensis var. utahensis A. Gray -- accepted -- Utah fleabane
  Erigeron vagus Payson -- accepted -- rambling fleabane, loose daisy
  Erigeron velutipes Hook. & Arn. -- accepted -- Chihuahuan fleabane
  Erigeron venustus Botsch. -- not accepted
  Erigeron vernus (L.) Torr. & A. Gray -- accepted -- early whitetop fleabane
  Erigeron versicolor (Greenm.) G.L. Nesom -- accepted -- changing fleabane
  Erigeron vetensis Rydb. -- accepted -- early bluetop fleabane
  Erigeron vicinus G.L. Nesom -- accepted -- neighbor fleabane
  Erigeron villarsii Bellardi -- not accepted
  Erigeron viscidus Rydb. -- not accepted
  Erigeron vreelandii Greene -- accepted -- Vreeland's erigeron, broadleaf daisy
  Erigeron wahwahensis S.L. Welsh -- not accepted
  Erigeron warnockii (Shinners) Shinners -- not accepted
  Erigeron watsonii (A. Gray) Cronquist -- accepted -- Watson's fleabane, Watson's daisy
  Erigeron wilkenii O'Kane -- accepted -- Dieter's erigeron
  Erigeron wyomingia Rydb. -- not accepted
  Erigeron X arthurii B. Boivin -- not accepted
  Erigeron yukonensis Rydb. -- accepted -- Yukon fleabane
  Erigeron zothecinus S.L. Welsh -- not accepted -- Lake Powell fleabane
  Eriocarpum australe Greene -- not accepted
  Eriocarpum coloradoense (A. Gray) Greene -- not accepted
  Eriocarpum grindelioides Nutt. -- not accepted
  Eriocarpum megacephalum Nash -- not accepted
  Eriocarpum scabrellum Greene -- not accepted
  Eriocarpum spinulosum (Pursh) Greene -- not accepted
  Eriocarpum wootonii Greene -- not accepted
  Eriophyllum Lag. -- accepted -- woolly sunflower, eriophyllum
  Eriophyllum ambiguum (A. Gray) A. Gray -- accepted -- beautiful woolly sunflower, beautiful woollysunflower
  Eriophyllum ambiguum var. ambiguum (A. Gray) A. Gray -- accepted -- beautiful woolly sunflower
  Eriophyllum ambiguum var. paleaceum (Brandegee) Ferris -- accepted -- beautiful woolly sunflower, beautiful woollysunflower
  Eriophyllum confertiflorum (DC.) A. Gray -- accepted -- golden-yarrow, yellow-yarrow
  Eriophyllum confertiflorum var. confertiflorum (DC.) A. Gray -- accepted -- golden-yarrow
  Eriophyllum confertiflorum var. discoideum (Rydb.) Munz -- not accepted
  Eriophyllum confertiflorum var. latum H.M. Hall -- not accepted
  Eriophyllum confertiflorum var. laxiflorum A. Gray -- not accepted
  Eriophyllum confertiflorum var. tanacetiflorum (Greene) Jeps. -- accepted -- golden-yarrow
  Eriophyllum confertiflorum var. tridactylum (Rydb.) Munz -- not accepted
  Eriophyllum congdonii Brandegee -- accepted -- Congdon's woolly sunflower
  Eriophyllum integrifolium (Hook.) Greene -- not accepted
  Eriophyllum jepsonii Greene -- accepted -- Jepson's woolly sunflower
  Eriophyllum lanatum (Pursh) Forbes -- accepted -- common woolly sunflower, wooly daisy, woody eriophyllum, woolly eriophyllum
  Eriophyllum lanatum var. achillaeoides (DC.) Jeps. -- not accepted -- common woolly sunflower
  Eriophyllum lanatum var. achillioides (DC.) Jeps. -- accepted -- common woolly sunflower
  Eriophyllum lanatum var. aphanactis J.T. Howell -- not accepted -- common woolly sunflower
  Eriophyllum lanatum var. arachnoideum (Fisch. & Avé-Lall.) Jeps. -- accepted -- common woolly sunflower
  Eriophyllum lanatum var. croceum (Greene) Jeps. -- accepted -- common woolly sunflower
  Eriophyllum lanatum var. cuneatum (Kellogg) Jeps. -- not accepted -- common woolly sunflower, common eriophyllum
  Eriophyllum lanatum var. grandiflorum (A. Gray) Jeps. -- accepted -- common woolly sunflower
  Eriophyllum lanatum var. hallii Constance -- accepted -- Hall's woolly sunflower
  Eriophyllum lanatum var. integrifolium (Hook.) Smiley -- accepted -- common woolly sunflower, wholeleaf eriophyllum
  Eriophyllum lanatum var. lanatum (Pursh) Forbes -- accepted -- common woolly sunflower, common eriophyllum
  Eriophyllum lanatum var. lanceolatum (Howell) Jeps. -- accepted -- common woolly sunflower
  Eriophyllum lanatum var. leucophyllum (DC.) W.R. Carter -- accepted -- common woolly sunflower
  Eriophyllum lanatum var. monoense (Rydb.) Jeps. -- not accepted
  Eriophyllum lanatum var. obovatum (Greene) H.M. Hall -- accepted -- common woolly sunflower
  Eriophyllum lanatum var. typicum Constance -- not accepted
  Eriophyllum lanosum (A. Gray) A. Gray -- accepted -- white easterbonnets
  Eriophyllum latilobum Rydb. -- accepted -- San Mateo woolly sunflower
  Eriophyllum mohavense (I.M. Johnst.) Jeps. -- accepted -- Mojave woolly sunflower
  Eriophyllum multicaule (DC.) A. Gray -- accepted -- manystem woolly sunflower, many-stem woolly-sunflower
  Eriophyllum nevinii A. Gray -- not accepted -- Nevin's woolly sunflower
  Eriophyllum nubigenum Greene ex A. Gray -- accepted -- Yosemite woolly sunflower
  Eriophyllum nubigenum var. congdonii (Brandegee) Constance -- not accepted
  Eriophyllum pringlei A. Gray -- accepted -- Pringle's woolly sunflower, wooly sunflower, Pringle's eriophyllum
  Eriophyllum staechadifolium Lag. -- accepted -- seaside woolly sunflower
  Eriophyllum staechadifolium var. artemisiifolium (Less.) J.F. Macbr. -- not accepted
  Eriophyllum staechadifolium var. depressum Greene -- not accepted
  Eriophyllum tanacetiflorum Greene -- not accepted
  Eriophyllum wallacei (A. Gray) A. Gray -- accepted -- woolly easterbonnets
  Eriophyllum wallacei ssp. australe (Rydb.) Wiggins -- not accepted
  Eriophyllum wallacei var. calvescens S.F. Blake -- not accepted
  Eriophyllum wallacei var. rubellum (A. Gray) A. Gray -- not accepted
  Erlangea Sch. Bip. -- accepted -- erlangea
  Erythremia grandiflora Nutt. -- not accepted
  Eschenbachia coulteri (A. Gray) Rydb. -- not accepted
  Eschenbachia lyrata (Kunth) Britton & Millsp. -- not accepted
  Eschenbachia tenuisecta (A. Gray) Woot. & Standl. -- not accepted
  Espeletia Mutis ex Bonpl. -- accepted
  Espeletia amplexicaulis Nutt. -- not accepted
  Espeletia schultzii Wedd. -- accepted
  Ethulia sparganophora L. -- not accepted
  Eucephalus Nutt. -- accepted -- aster, eucephalus
  Eucephalus breweri (A. Gray) G.L. Nesom -- accepted -- Brewer's aster
  Eucephalus brickellioides (Greene) G.L. Nesom -- not accepted -- brickellbush aster
  Eucephalus covillei Greene -- not accepted
  Eucephalus elegans Nutt. -- accepted -- elegant aster
  Eucephalus engelmannii (D.C. Eaton) Greene -- accepted -- Engelmann's aster
  Eucephalus formosus Greene -- not accepted
  Eucephalus glabratus (Greene) Greene -- accepted -- smooth aster
  Eucephalus glaucescens (A. Gray) Greene -- accepted -- Klickitat aster
  Eucephalus glaucus Nutt. -- not accepted
  Eucephalus gormanii Piper -- accepted -- Gorman's aster
  Eucephalus ledophyllus (A. Gray) Greene -- accepted -- Cascade aster
  Eucephalus ledophyllus var. covillei (Greene) G.L. Nesom -- accepted -- Cascade aster
  Eucephalus ledophyllus var. ledophyllus (A. Gray) Greene -- accepted -- Cascade aster
  Eucephalus paucicapitatus (B.L. Rob.) Greene -- accepted -- Olympic Mountain aster
  Eucephalus perelegans (A. Nelson & J.F. Macbr.) W.A. Weber -- not accepted
  Eucephalus tomentellus (Greene) Greene -- accepted -- rayless aster
  Eucephalus vialis Bradshaw -- accepted -- wayside aster
  Euchiton Cass. -- accepted -- euchiton
  Euchiton gymnocephalus (DC.) Anderb. -- accepted -- creeping cudweed
  Euchiton involucratus (G. Forst.) Anderb. -- accepted
  Euchiton japonicus (Thunb.) Anderb. -- accepted -- father-and-child plant
  Euchiton sphaericus (Willd.) Anderb. -- accepted -- tropical creeping cudweed
  Eupatoriadelphus King & H. Rob. -- accepted
  Eupatoriadelphus dubius (Willd. ex Poir.) King & H. Rob. -- not accepted
  Eupatoriadelphus fistulosus (Barratt) King & H. Rob. -- not accepted
  Eupatoriadelphus maculatus (L.) King & H. Rob. -- accepted -- spotted trumpetweed
  Eupatoriadelphus maculatus var. bruneri (A. Gray) King & H. Rob. -- not accepted
  Eupatoriadelphus maculatus var. foliosum (Fernald) Kartesz -- not accepted
  Eupatoriadelphus maculatus var. maculatus (L.) King & H. Rob. -- not accepted
  Eupatoriadelphus purpureus (L.) King & H. Rob. -- not accepted
  Eupatoriadelphus steelei (E.E. Lamont) G.J. Schmidt & E.E. Schill. -- not accepted
  Eupatorium L. -- accepted -- thoroughwort
  Eupatorium adenophorum Spreng. -- not accepted
  Eupatorium album L. -- accepted -- white thoroughwort
  Eupatorium album var. album L. -- accepted -- white thoroughwort
  Eupatorium album var. glandulosum (Michx.) DC. -- not accepted -- white thoroughwort
  Eupatorium album var. monardifolium Fernald -- not accepted
  Eupatorium album var. subvenosum A. Gray -- accepted -- white thoroughwort
  Eupatorium album var. vaseyi (Porter) Cronquist -- accepted -- upland boneset
  Eupatorium altissimum L. -- accepted -- tall thoroughwort, tall joepyeweed
  Eupatorium anomalum Nash -- accepted -- Florida thoroughwort
  Eupatorium aromaticum L. -- not accepted
  Eupatorium aromaticum var. incisum A. Gray -- not accepted
  Eupatorium azureum DC. -- not accepted -- blue boneset
  Eupatorium betonicifolium Mill. -- not accepted -- betonyleaf thoroughwort
  Eupatorium bigelovii A. Gray -- not accepted -- Bigelow's thoroughwort
  Eupatorium borinquense (Britton) B.L. Rob. -- not accepted -- limestone thoroughwort
  Eupatorium bruneri A. Gray -- not accepted
  Eupatorium cannabinum L. -- accepted -- hemp agrimony
  Eupatorium capillifolium (Lam.) Small -- accepted -- dogfennel
  Eupatorium capillifolium var. leptophyllum (DC.) H.E. Ahles -- not accepted
  Eupatorium chapmanii Small -- not accepted -- Chapman's thoroughwort
  Eupatorium coelestinum L. -- not accepted -- blue mistflower
  Eupatorium compositifolium Walter -- accepted -- yankeeweed, dogfennel eupatorium
  Eupatorium cordatum Burm. f. -- not accepted
  Eupatorium cordigerum (Fernald) Fernald -- not accepted
  Eupatorium corymbosum Aubl. -- not accepted -- Caribbean thoroughwort
  Eupatorium cuneatum (Engelm. ex A. Gray) Engelm. ex Small -- not accepted
  Eupatorium cuneifolium Willd. -- not accepted
  Eupatorium cuneifolium var. semiserratum (DC.) Fernald & Grisc. -- not accepted
  Eupatorium dolicholepis (Urb.) Britton -- not accepted -- oreganillo
  Eupatorium droserolepis B.L. Rob. -- not accepted -- Monte Torrecilla thoroughwort
  Eupatorium dubium Willd. ex Poir. -- not accepted -- coastalplain joepyeweed
  Eupatorium eugenei Small -- not accepted
  Eupatorium falcatum Michx. -- not accepted
  Eupatorium fendleri (A. Gray) A. Gray -- not accepted
  Eupatorium fernaldii Godfrey -- not accepted
  Eupatorium fistulosum Barratt -- not accepted -- joepyeweed, joe-pye-weed, trumpetweed
  Eupatorium frustratum B.L. Rob. -- not accepted -- Cape Sable thoroughwort
  Eupatorium geraniifolium Urb. -- not accepted -- geraniumleaf thoroughwort
  Eupatorium glandulosum Kunth non Michx. -- not accepted
  Eupatorium glandulosum Michx. -- not accepted
  Eupatorium glaucescens Elliot -- not accepted -- waxy thoroughwort
  Eupatorium godfreyanum Cronquist -- accepted -- Godfrey's thoroughwort
  Eupatorium greggii A. Gray -- not accepted -- palmleaf thoroughwort
  Eupatorium havanense Kunth -- not accepted
  Eupatorium herbaceum (A. Gray) Greene -- not accepted
  Eupatorium holzingeri Rydb. -- not accepted
  Eupatorium hyssopifolium L. -- accepted -- hyssopleaf thoroughwort
  Eupatorium hyssopifolium var. calcaratum Fernald & B.G. Schub. -- not accepted -- hyssopleaf thoroughwort
  Eupatorium hyssopifolium var. hyssopifolium L. -- accepted -- hyssopleaf thoroughwort
  Eupatorium hyssopifolium var. laciniatum A. Gray -- accepted -- hyssopleaf thoroughwort
  Eupatorium hyssopifolium var. linearifolium (Walter) Fernald -- not accepted
  Eupatorium incarnatum Walter -- not accepted -- pink thoroughwort
  Eupatorium iresinoides Kunth -- not accepted -- villalba
  Eupatorium ivifolium L. -- not accepted -- ivyleaf thoroughwort
  Eupatorium juncundum Greene -- not accepted
  Eupatorium lancifolium (Torr. & A. Gray) Small -- accepted -- lanceleaf thoroughwort
  Eupatorium latidens Small -- not accepted
  Eupatorium lecheifolium Greene -- not accepted
  Eupatorium lemmonii B.L. Rob. -- not accepted
  Eupatorium leptophyllum DC. -- accepted -- false fennel
  Eupatorium leucolepis (DC.) Torr. & A. Gray -- accepted -- justiceweed
  Eupatorium leucolepis var. leucolepis (DC.) Torr. & A. Gray -- accepted -- justiceweed
  Eupatorium leucolepis var. novae-angliae Fernald -- accepted -- justiceweed
  Eupatorium linearifolium Walter -- accepted -- waxy thoroughwort
  Eupatorium linearifolium sensu Michx. non Walter -- not accepted
  Eupatorium luciae-brauniae Fernald -- not accepted
  Eupatorium macrophyllum L. -- not accepted -- largeleaf thoroughwort
  Eupatorium maculatum L. -- not accepted -- spotted joepyeweed, spotted joe-pye-weed
  Eupatorium maculatum ssp. bruneri (A. Gray) G.W. Douglas -- not accepted
  Eupatorium maculatum var. bruneri (A. Gray) Breitung -- not accepted -- spotted joepyeweed, spotted joe-pye-weed
  Eupatorium maculatum var. foliosum (Fernald) Wiegand -- not accepted -- spotted joepyeweed
  Eupatorium maculatum var. maculatum L. -- not accepted -- spotted joepyeweed
  Eupatorium microstemon Cass. -- not accepted -- tropical thoroughwort
  Eupatorium mikanioides Chapm. -- accepted -- semaphore thoroughwort
  Eupatorium mohrii Greene -- accepted -- Mohr's thoroughwort
  Eupatorium occidentale Hook. -- not accepted
  Eupatorium odoratum L. -- not accepted -- Jack in the bush
  Eupatorium oteroi Monach. -- not accepted -- Mona Island thoroughwort
  Eupatorium parryi A. Gray -- not accepted
  Eupatorium pauperculum A. Gray -- not accepted
  Eupatorium pectinatum Small -- not accepted
  Eupatorium perfoliatum L. -- accepted -- common boneset, Chapman's thoroughwort, boneset
  Eupatorium perfoliatum var. colpophilum Fernald & Grisc. -- not accepted -- common boneset
  Eupatorium perfoliatum var. cuneatum Engelm. ex A. Gray -- not accepted
  Eupatorium perfoliatum var. perfoliatum L. -- not accepted -- common boneset
  Eupatorium perfoliatum var. truncatum (Muhl. ex Willd.) A. Gray -- not accepted
  Eupatorium petaloideum Britton ex Small -- accepted -- snowy white thoroughwort
  Eupatorium pilosum Walter -- accepted -- rough boneset
  Eupatorium polyodon Urb. -- not accepted -- islandthicket thoroughwort
  Eupatorium portoricense Urb. -- not accepted -- Puerto Rico thoroughwort
  Eupatorium pubescens Muhl. ex Willd. -- not accepted
  Eupatorium purpureum L. -- not accepted -- sweetscented joepyeweed
  Eupatorium purpureum var. amoenum (Pursh) A. Gray -- not accepted
  Eupatorium purpureum var. foliosum Fernald -- not accepted
  Eupatorium purpureum var. holzingeri (Rydb.) E. Lamont -- not accepted -- Holzinger's eupatorium
  Eupatorium purpureum var. maculatum (L.) Darl. -- not accepted
  Eupatorium purpureum var. purpureum L. -- not accepted -- sweetscented joepyeweed
  Eupatorium pycnocephalum Less. -- not accepted -- lavender thoroughwort
  Eupatorium recurvans Small -- not accepted
  Eupatorium resinifluum Urb. -- not accepted
  Eupatorium resinosum Torr. ex DC. -- accepted -- pine barren thoroughwort
  Eupatorium resinosum var. kentuckiense Fernald -- not accepted
  Eupatorium riparium Regel -- not accepted
  Eupatorium roanense Small -- not accepted
  Eupatorium rothrockii A. Gray -- not accepted
  Eupatorium rotundifolium L. -- accepted -- roundleaf thoroughwort, roundleaf eupatorium
  Eupatorium rotundifolium ssp. ovatum (Bigelow) J.D. Montgom. & Fairbrothers -- not accepted
  Eupatorium rotundifolium var. cordigerum Fernald -- not accepted -- roundleaf thoroughwort
  Eupatorium rotundifolium var. ovatum (Bigelow) Torr. -- accepted -- roundleaf thoroughwort
  Eupatorium rotundifolium var. rotundifolium L. -- accepted -- roundleaf thoroughwort
  Eupatorium rotundifolium var. saundersii (Porter ex Britton) Cronquist -- not accepted
  Eupatorium rotundifolium var. scabridum (Elliot) A. Gray -- accepted -- roundleaf thoroughwort
  Eupatorium rugosum Houtt. -- not accepted -- richweed, snakeroot, white snakeroot
  Eupatorium rugosum var. angustata (A. Gray) S.F. Blake -- not accepted
  Eupatorium rugosum var. chlorolepis Fernald -- not accepted
  Eupatorium rugosum var. roanense (Small) Fernald -- not accepted
  Eupatorium rugosum var. tomentellum (B.L. Rob.) S.F. Blake -- not accepted
  Eupatorium rugosum var. villicaule (Fernald) S.F. Blake -- not accepted
  Eupatorium saltuense Fernald, non Agertina altissima (L.) King & H. Rob. -- not accepted
  Eupatorium scabridum Elliot -- not accepted
  Eupatorium semiserratum DC. -- accepted -- smallflower thoroughwort, smallflower eupatorium
  Eupatorium semiserratum var. lancifolium Torr. & A. Gray -- not accepted
  Eupatorium serotinum Michx. -- accepted -- lateflowering thoroughwort, late eupatorium
  Eupatorium serotinum var. polyneuron F.J. Herm. -- not accepted
  Eupatorium sessilifolium L. -- accepted -- upland boneset
  Eupatorium sessilifolium var. brittonianum Porter -- not accepted -- upland boneset
  Eupatorium sessilifolium var. sessilifolium L. -- not accepted -- upland boneset
  Eupatorium sessilifolium var. vaseyi (Porter) Fernald & Grisc. -- not accepted -- upland boneset
  Eupatorium shastense D.W. Taylor & Stebbins -- not accepted -- Shasta eupatorium
  Eupatorium sinuatum Lam. -- not accepted -- wavyleaf thoroughwort
  Eupatorium smithii Greene & C. Mohr -- not accepted
  Eupatorium solidaginifolium A. Gray -- not accepted -- shrubby thoroughwort
  Eupatorium sonorae A. Gray -- not accepted -- Sonoran thoroughwort
  Eupatorium sordidum Less. -- accepted -- dirty thoroughwort
  Eupatorium steelei E. Lamont -- not accepted -- Steele's eupatorium
  Eupatorium texense (Torr. & A. Gray) Rydb. -- not accepted
  Eupatorium torreyanum Short & Peter -- not accepted
  Eupatorium tortifolium Chapm. -- not accepted
  Eupatorium trifoliatum L. -- not accepted
  Eupatorium trifoliatum var. foliosum (Fernald) Farw. -- not accepted
  Eupatorium triplinerve Vahl -- not accepted -- yapana
  Eupatorium urticifolium Reichard -- not accepted
  Eupatorium urticifolium var. tomentellum B.L. Rob. -- not accepted
  Eupatorium vaseyi Porter -- not accepted
  Eupatorium verbenifolium Reichard -- not accepted
  Eupatorium veronicifolium Kunth -- not accepted
  Eupatorium villosum Sw. -- not accepted -- Florida Keys thoroughwort
  Eupatorium wrightii A. Gray -- not accepted
  Eupatorium X cordigerum (Fernald) Fernald (pro sp.) -- accepted -- roundleaf thoroughwort
  Eupatorium X pinnatifidum Elliot -- accepted -- eupatorium
  Eupatorium X polyneuron (F.J. Herm.) Wunderlin -- not accepted
  Eupatorium X truncatum Muhl. ex Willd. (pro sp.) -- not accepted -- eupatorium
  Eurybia (Cass.) Cass. -- accepted -- aster
  Eurybia avita (Alexander) G.L. Nesom -- accepted -- Alexander's rock aster
  Eurybia chapmanii (Torr. & A. Gray) G.L. Nesom -- not accepted -- savannah aster
  Eurybia chlorolepis (Burgess) G.L. Nesom -- accepted -- mountain aster
  Eurybia commixta Nees -- not accepted
  Eurybia compacta G.L. Nesom -- accepted -- slender aster
  Eurybia conspicua (Lindl.) G.L. Nesom -- accepted -- western showy aster, eastern showy aster
  Eurybia divaricata (L.) G.L. Nesom -- accepted -- white wood aster
  Eurybia eryngiifolia (Torr. & A. Gray) G.L. Nesom -- accepted -- thistleleaf aster
  Eurybia furcata (Burgess) G.L. Nesom -- accepted -- forked aster
  Eurybia glauca (Nutt.) G.L. Nesom -- not accepted -- gray aster
  Eurybia glomerata Bernh. ex Nees -- not accepted
  Eurybia hemispherica (Alexander) G.L. Nesom -- accepted -- southern prairie aster
  Eurybia horrida (Woot. & Standl.) G.L. Nesom -- not accepted -- horrid herrickia
  Eurybia integrifolia (Nutt.) G.L. Nesom -- accepted -- thickstem aster
  Eurybia jonesiae (Lamboy) G.L. Nesom -- accepted -- Jones' aster
  Eurybia macrophylla (L.) Cass. -- accepted -- bigleaf aster
  Eurybia merita (A. Nelson) G.L. Nesom -- accepted -- subalpine aster
  Eurybia mirabilis (Torr. & A. Gray) G.L. Nesom -- accepted -- bouquet aster
  Eurybia paludosa (Aiton) G.L. Nesom -- accepted -- southern swamp aster
  Eurybia pulchra (S.F. Blake) G.L. Nesom -- not accepted -- beautiful aster
  Eurybia pygmaea (Lindl.) G.L. Nesom -- not accepted
  Eurybia radula (Aiton) G.L. Nesom -- accepted -- low rough aster
  Eurybia radulina (A. Gray) G.L. Nesom -- accepted -- roughleaf aster
  Eurybia saxicastellii (J.J.N. Campbell & M. Medley) G.L. Nesom -- accepted -- rockcastle aster
  Eurybia schreberi (Nees) Nees -- accepted -- Schreber's aster
  Eurybia sibirica (L.) G.L. Nesom -- accepted -- arctic aster, Siberian aster
  Eurybia sibirica var. gigantea (Hook.) G.L. Nesom -- not accepted
  Eurybia spectabilis (Aiton) G.L. Nesom -- accepted -- eastern showy aster, western showy aster
  Eurybia spinulosa (Chapm.) G.L. Nesom -- accepted -- Apalachicola aster
  Eurybia surculosa (Michx.) G.L. Nesom -- accepted -- creeping aster
  Eurybia wasatchensis (M.E. Jones) G.L. Nesom -- not accepted -- Wasatch aster
  Eurybia X herveyi (A. Gray) G.L. Nesom -- accepted
  Euryops (Cass.) Cass. -- accepted -- euryops
  Euryops chrysanthemoides (DC.) B. Nord. -- accepted -- bull's eye
  Euryops multifidus (Thunb.) DC. -- accepted -- hawk's eye, euryops
  Euryops subcarnosus ssp. vulgaris B. Nord -- not accepted
  Euthamia Nutt. ex Cass. -- accepted -- goldentop
  Euthamia californica Gandog. -- not accepted
  Euthamia camporum Greene -- not accepted
  Euthamia caroliniana (L.) Greene ex Porter & Britton -- not accepted
  Euthamia chrysothamnoides Greene -- not accepted
  Euthamia floribunda Greene -- not accepted
  Euthamia galetorum Greene -- not accepted
  Euthamia glutinosa Rydb. -- not accepted
  Euthamia graminifolia (L.) Nutt. -- accepted -- flat-top goldentop, slender goldentop, flattop goldentop
  Euthamia graminifolia var. galetorum (Greene) Friesner -- not accepted
  Euthamia graminifolia var. graminifolia (L.) Nutt. -- not accepted -- flat-top goldentop
  Euthamia graminifolia var. hirtipes (Fernald) C.E.S. Taylor & R.J. Taylor -- not accepted -- flat-top goldentop
  Euthamia graminifolia var. major (Michx.) Moldenke -- not accepted
  Euthamia graminifolia var. nuttallii (Greene) W. Stone -- not accepted -- flat-top goldentop
  Euthamia gymnospermoides Greene -- accepted -- Texas goldentop
  Euthamia hirtipes (Fernald) Sieren (pro hybr.) -- not accepted
  Euthamia leptocephala (Torr. & A. Gray) Greene ex Porter & Britton -- accepted -- bushy goldentop
  Euthamia linearifolia Gandog. -- not accepted
  Euthamia media Greene -- not accepted
  Euthamia microcephala Greene -- not accepted
  Euthamia microphylla Greene -- not accepted
  Euthamia minor (Michx.) Greene -- not accepted
  Euthamia nuttallii Greene -- not accepted
  Euthamia occidentalis Nutt. -- accepted -- western goldentop, western goldenrod
  Euthamia pulverulenta Greene -- not accepted
  Euthamia remota Greene -- not accepted
  Euthamia tenuifolia (Pursh) Nutt. -- not accepted -- slender goldentop
  Euthamia tenuifolia var. pycnocephala (Fernald) C.E.S. Taylor & R.J. Taylor -- not accepted -- slender goldentop
  Euthamia tenuifolia var. tenuifolia (Pursh) Nutt. -- not accepted -- slender goldentop
  Eutrochium Raf. -- accepted
  Eutrochium dubium (Willd. ex Poir.) E.E. Lamont -- accepted -- coastal plain joepyeweed
  Eutrochium fistulosum (Barratt) E.E. Lamont -- accepted -- trumpetweed
  Eutrochium maculatum (L.) E.E. Lamont -- accepted -- spotted joepyeweed, eupatoire maculée
  Eutrochium maculatum var. bruneri (A. Gray) E.E. Lamont -- accepted -- spotted joepyeweed
  Eutrochium maculatum var. foliosum (Fernald) E.E. Lamont -- accepted -- spotted joepyeweed
  Eutrochium maculatum var. maculatum (L.) E.E. Lamont -- accepted -- spotted joepyeweed, eupatoire maculée
  Eutrochium purpureum (L.) E.E. Lamont -- accepted -- sweet joepyeweed, sweetscented joepyeweed
  Eutrochium purpureum var. holzingeri (Rydb.) E.E. Lamont -- accepted -- Holzinger's eupatorium
  Eutrochium purpureum var. purpureum (L.) E.E. Lamont -- accepted -- sweetscented joe pye weed
  Eutrochium steelei (E.E. Lamont) E.E. Lamont -- accepted -- Steele's eupatorium
  Evax Gaertn. -- not accepted -- pygmy cudweed
  Evax acaulis Greene non (Kellogg) Greene -- not accepted
  Evax acaulis (Kellogg) Greene -- not accepted
  Evax candida (Torr. & A. Gray) A. Gray -- not accepted -- silver pygmycudweed, silver evax
  Evax caulescens (Benth.) Gray -- not accepted -- involucrate pygmycudweed
  Evax caulescens var. humilis (Greene) Jeps. -- not accepted
  Evax caulescens var. petiolata A. Gray -- not accepted
  Evax involucrata Greene -- not accepted
  Evax multicaulis DC. -- not accepted
  Evax multicaulis var. drummondii (Torr. & A. Gray) A. Gray -- not accepted
  Evax prolifera Nutt. ex DC. -- not accepted -- bighead pygmycudweed, rabbit tobacco, rabbit's tobacco
  Evax sparsiflora (A. Gray) Jeps. -- not accepted
  Evax sparsiflora var. brevifolia (A. Gray) Jeps. -- not accepted
  Evax verna Raf. -- not accepted -- spring pygmycudweed, spring pygmy-cudweed
  Evax verna var. drummondii (Torr. & A. Gray) Kartesz & Gandhi -- not accepted -- spring pygmycudweed
  Evax verna var. verna Raf. -- not accepted -- spring pygmycudweed, spring pygmy-cudweed
  Facelis Cass. -- accepted -- trampweed
  Facelis apiculata Cass. -- not accepted
  Facelis retusa (Lam.) Sch. Bip. -- accepted -- annual trampweed
  Felicia Cass. -- accepted
  Felicia amelloides (L.) Voss -- accepted -- blue daisy, blue marguerite
  Felicia amoena (Sch. Bip.) Levyns -- accepted
  Felicia fruticosa (L.) G. Nicholson -- accepted
  Felicia uliginosa (J.M. Wood & M.S. Evans) Grau -- not accepted
  Filaginella palustris (Nutt.) Holub -- not accepted
  Filaginella uliginosa (L.) Opiz -- not accepted
  Filaginopsis drummondii Torr. & A. Gray -- not accepted
  Filaginopsis multicaulis (DC.) Torr. & A. Gray -- not accepted
  Filago L. -- accepted -- cottonrose
  Filago arizonica A. Gray -- not accepted -- Arizona cottonrose
  Filago arvensis L. -- not accepted -- field cottonrose
  Filago californica Nutt. -- not accepted -- California cottonrose, California fluffweed
  Filago candida (Torr. & A. Gray) Shinners -- not accepted
  Filago depressa A. Gray -- not accepted -- dwarf cottonrose, dwarf filago
  Filago gallica L. -- not accepted -- narrowleaf cottonrose
  Filago germanica Huds. -- not accepted
  Filago germanica L. 1763 non Filago germanica Huds. 1762 -- not accepted
  Filago minima (Sm.) Pers. -- not accepted -- little cottonrose
  Filago nivea Small -- not accepted
  Filago nuttallii Shinners -- not accepted
  Filago prolifera (Nutt. ex DC.) Britton non Pomel -- not accepted
  Filago pyramidata L. -- accepted -- broadleaf cottonrose
  Filago pyramidata var. pyramidata L. -- accepted -- cottonrose, filzkraut
  Filago verna (Raf.) Shinners -- not accepted
  Filago verna var. drummondii (Torr. & A. Gray) Shinners -- not accepted
  Filago vulgaris Lam. -- accepted -- common cottonrose
  Filifolium Kitam. -- accepted
  Filifolium sibiricum (L.) Kitam. -- accepted
  Fitchia Hook. f. -- accepted -- fitchia
  Fitchia speciosa Cheeseman -- accepted -- burr daisytree, burrdaisytree
  Flaveria Juss. -- accepted -- yellowtops
  Flaveria bidentis (L.) Kuntze -- accepted -- coastal plain yellowtops, coastalplain yellowtops
  Flaveria brownii A. Powell -- accepted -- Brown's yellowtops
  Flaveria campestris J.R. Johnst. -- accepted -- alkali yellowtops
  Flaveria chlorifolia A. Gray -- accepted -- clasping yellowtops
  Flaveria floridana J.R. Johnst. -- accepted -- Florida yellowtops
  Flaveria latifolia (J.R. Johnst.) Rydb. -- not accepted
  Flaveria linearis Lag. -- accepted -- narrowleaf yellowtops
  Flaveria macdougalii Theroux, Pinkava & Keil -- not accepted -- MacDougal's yellowtops
  Flaveria mcdougallii Theroux, Pinkava & Keil -- accepted
  Flaveria oppositifolia auct. non (DC.) Rydb. -- not accepted
  Flaveria trinervia (Spreng.) C. Mohr -- accepted -- clustered yellowtops
  Flaveria X latifolia (J.R. Johnst.) Long & Rhamstine non Flaveria latifolia (J.R. Johnst.) Rydb. -- not accepted
  Fleischmannia Sch. Bip. -- accepted -- thoroughwort
  Fleischmannia incarnata (Walter) King & H. Rob. -- accepted -- pink thoroughwort
  Fleischmannia microstemon (Cass.) King & H. Rob. -- accepted -- tropical thoroughwort
  Fleischmannia pycnocephala (Less.) King & H. Rob. -- accepted -- lavender thoroughwort
  Fleischmannia sonorae (A. Gray) King & H. Rob. -- accepted -- Sonoran thoroughwort
  Florestina Cass. -- accepted -- florestina
  Florestina tripteris DC. -- accepted -- sticky florestina
  Flourensia DC. -- accepted -- tarwort
  Flourensia cernua DC. -- accepted -- American tarwort, tarbush
  Flourensia pringlei (A. Gray) S.F. Blake -- accepted -- Pringle's tarwort
  Flyriella King & H. Rob. -- accepted -- brickellbush
  Flyriella parryi (A. Gray) King & H. Rob. -- accepted -- Chisos Mountain brickellbush
  Franseria acanthicarpa (Hook.) Coville -- not accepted
  Franseria ambrosioides Cav. -- not accepted
  Franseria chamissonis Less. -- not accepted
  Franseria chamissonis ssp. bipinnatisecta (Less.) Wiggins & Stockw. -- not accepted
  Franseria chamissonis var. bipinnatisecta Less. -- not accepted
  Franseria chenopodiifolia Benth. -- not accepted
  Franseria confertiflora (DC.) Rydb. -- not accepted
  Franseria cordifolia A. Gray -- not accepted
  Franseria deltoidea Torr. -- not accepted
  Franseria discolor Nutt. -- not accepted -- skeletonleaf bursage
  Franseria dumosa A. Gray -- not accepted
  Franseria eriocentra A. Gray -- not accepted
  Franseria ilicifolia A. Gray -- not accepted
  Franseria linearis Rydb. -- not accepted
  Franseria pumila Nutt. -- not accepted
  Franseria strigulosa Rydb. -- not accepted
  Franseria tomentosa (Nutt.) A. Nelson, non A. Gray -- not accepted -- bur ragweed
  Franseria tomentosa A. Gray -- not accepted
  Gaertnera tomentosa (A. Gray) Kuntze -- not accepted
  Gaertneria acanthicarpa (Hook.) Britton -- not accepted
  Gaertneria discolor (Nutt.) Kuntze -- not accepted
  Gaertneria grayi A. Nelson -- not accepted
  Gaertneria tenuifolia Harv. & A. Gray -- not accepted
  Gaertneria tomentosa (Nutt.) A. Heller -- not accepted
  Gaillardia Foug. -- accepted -- blanketflower, gaillardia
  Gaillardia aestivalis (Walter) H. Rock -- accepted -- lanceleaf blanketflower, Winkler's blanketflower, lanceleaf gaillardia
  Gaillardia aestivalis var. aestivalis (Walter) H. Rock -- not accepted -- lanceleaf blanketflower, prairie gaillardia
  Gaillardia aestivalis var. flavovirens (C. Mohr) Cronquist -- not accepted -- lanceleaf blanketflower
  Gaillardia aestivalis var. winkleri (Cory) B.L. Turner -- not accepted -- Winkler's blanketflower
  Gaillardia amblyodon J. Gay -- accepted -- maroon blanketflower
  Gaillardia aristata Pursh -- accepted -- common gaillardia, gaillardia, great blanket-flower
  Gaillardia arizonica A. Gray -- accepted -- Arizona blanketflower, Pringle's blanketflower
  Gaillardia arizonica var. arizonica A. Gray -- not accepted -- Arizona blanketflower
  Gaillardia arizonica var. pringlei (Rydb.) S.F. Blake -- not accepted -- Pringle's blanketflower
  Gaillardia chrysantha Small -- not accepted
  Gaillardia coahuilensis B.L. Turner -- accepted -- bandanna daisy
  Gaillardia drummondii (Hook.) DC. -- not accepted
  Gaillardia fastigiata Greene -- not accepted
  Gaillardia flava Rydb. -- accepted -- yellow blanketflower
  Gaillardia gracilis A. Nelson -- not accepted
  Gaillardia lanceolata Michx. -- not accepted
  Gaillardia lanceolata var. fastigiata (Greene) Waterf. -- not accepted
  Gaillardia lanceolata var. flavovirens C. Mohr -- not accepted
  Gaillardia lutea Greene -- not accepted
  Gaillardia lutea var. winkleri Cory -- not accepted
  Gaillardia mearnsii Rydb. -- not accepted
  Gaillardia mexicana auct. non A. Gray -- not accepted
  Gaillardia multiceps Greene -- accepted -- onion blanketflower
  Gaillardia multiceps var. microcephala B.L. Turner -- not accepted -- onion blanketflower
  Gaillardia multiceps var. multiceps Greene -- not accepted -- onion blanketflower
  Gaillardia neomexicana A. Nelson -- not accepted
  Gaillardia parryi Greene -- accepted -- Parry's blanketflower
  Gaillardia picta D. Don -- not accepted
  Gaillardia pinnatifida Torr. -- accepted -- red dome blanketflower, yellow blanketflower, red-dome blanketflower, blanketflower, slender gaillardia
  Gaillardia pinnatifida var. linearis (Rydb.) Biddulph -- not accepted -- red dome blanketflower, reddome blanketflower
  Gaillardia pinnatifida var. pinnatifida Torr. -- not accepted -- red dome blanketflower
  Gaillardia pringlei Rydb. -- not accepted
  Gaillardia pulchella Foug. -- accepted -- firewheel, Indianblanket, rosering gaillardia, Indian blanket
  Gaillardia pulchella var. australis Turner & M.A. Whalen -- not accepted -- firewheel
  Gaillardia pulchella var. picta (D. Don) A. Gray -- not accepted -- firewheel
  Gaillardia pulchella var. pulchella Foug. -- not accepted -- firewheel
  Gaillardia rigida Small ex Rydb. -- not accepted
  Gaillardia serotina (Walter) H. Rock -- not accepted
  Gaillardia spathulata A. Gray -- accepted -- western blanketflower
  Gaillardia suavis (A. Gray & Engelm.) Britton & Rusby -- accepted -- perfumeballs, sweet gaillardia
  Gaillardia trinervata Small -- not accepted
  Gaillardia villosa Rydb. -- not accepted
  Gaillardia X grandiflora Van Houtte -- accepted
  Galatella Cass. -- accepted
  Galatella punctata (Waldst. & Kit.) Nees -- accepted
  Galinsoga Ruiz & Pav. -- accepted -- gallant soldier, galinsoga, gallant-soldier
  Galinsoga aristulata E.P. Bicknell -- not accepted
  Galinsoga bicolorata H. St. John & D. White -- not accepted
  Galinsoga caracasana (DC.) Sch. Bip. -- not accepted
  Galinsoga ciliata (Raf.) S.F. Blake -- not accepted -- shaggy soldier
  Galinsoga ciliata auct. non (Raf.) S.F. Blake -- not accepted
  Galinsoga parviflora Cav. -- accepted -- gallant soldier, small-flower galinsoga, littleflower quickweed, gallant-soldier, gallantsoldier
  Galinsoga parviflora var. parviflora Cav. -- accepted
  Galinsoga parviflora var. semicalva A. Gray -- accepted
  Galinsoga quadriradiata Cav. -- accepted -- shaggy soldier, hairy galinsoga, fringed quickweed, shaggy-soldier
  Galinsoga semicalva (A. Gray) H. St. John & D. White -- not accepted
  Galinsoga semicalva var. percalva S.F. Blake -- not accepted
  Galinsoga urticifolia (Kunth) Benth. -- accepted -- nettle-leaf soldier
  Gamochaeta Wedd. -- accepted -- everlasting
  Gamochaeta americana (Mill.) Wedd. -- accepted -- American everlasting
  Gamochaeta antillana (Urb.) Anderb. -- accepted
  Gamochaeta argyrinea G.L. Nesom -- accepted -- silvery cudweed
  Gamochaeta calviceps (Fernald) Cabrera -- accepted
  Gamochaeta chionesthes G.L. Nesom -- accepted
  Gamochaeta coarctata (Willd.) Kerguélen -- accepted -- gray everlasting
  Gamochaeta falcata (Lam.) Cabrera -- accepted -- narrowleaf purple everlasting
  Gamochaeta pensylvanica (Willd.) Cabrera -- accepted -- Pennsylvania everlasting
  Gamochaeta purpurea (L.) Cabrera -- accepted -- spoonleaf purple everlasting, spoon-leaf purple everlasting
  Gamochaeta simplicicaulis (Willd. ex Spreng.) Cabrera -- accepted -- simple-stem everlasting
  Gamochaeta sphacelata (Kunth) Cabrera -- accepted -- owl's crown
  Gamochaeta sphacilata (Kunth) Cabrera -- not accepted -- owl's crown
  Gamochaeta spicata (Lam.) Cabrera -- not accepted
  Gamochaeta stachydifolia (Lam.) Cabrera -- accepted
  Gamochaeta stagnalis (I.M. Johnst.) Anderb. -- accepted -- desert cudweed
  Gamochaeta ustulata (Nutt.) G.L. Nesom -- accepted -- featherweed
  Garberia A. Gray -- accepted -- garberia
  Garberia fruticosa (Nutt.) A. Gray -- not accepted
  Garberia heterophylla (Bartram) Merr. & F. Harper -- accepted -- garberia
  Gazania Gaertn. -- accepted -- gazania
  Gazania linearis (Thunb.) Druce -- accepted -- treasureflower
  Gazania longiscapa DC. -- not accepted
  Gazania rigens (L.) Gaertn. -- accepted -- treasure-flower
  Gazania splendens Lem. -- not accepted
  Geraea Torr. & A. Gray -- accepted -- desertsunflower, desert sunflower
  Geraea canescens Torr. & A. Gray -- accepted -- hairy desertsunflower, desert sunflower, desertgold
  Geraea canescens var. canescens Torr. & A. Gray -- not accepted -- hairy desertsunflower, hairy desert sunflower
  Geraea canescens var. paniculata (A. Gray) S.F. Blake -- not accepted -- hairy desertsunflower, hairy desert sunflower
  Geraea viscida (A. Gray) S.F. Blake -- accepted -- sticky desertsunflower
  Gerbera J.F. Gmel. -- accepted -- Transvaal daisy
  Gerbera jamesonii Bolus ex Hook. f. -- accepted -- Barberton daisy
  Gifola germanica Dumort. -- not accepted
  Glebionis Cass. -- accepted
  Glebionis carinatum (Schousb.) Tzvelev -- not accepted
  Glebionis coronarium (L.) Tzvelev -- accepted -- crowndaisy, garland chrysanthemum
  Glebionis segetum (L.) Fourr. -- accepted -- corndaisy
  Glossogyne Cass. -- accepted
  Glossogyne tenuifolia Cass. ex Less. -- accepted
  Glyptopleura D.C. Eaton -- accepted -- glyptopleura
  Glyptopleura marginata D.C. Eaton -- accepted -- carveseed
  Glyptopleura setulosa A. Gray -- accepted -- holy dandelion, holy-dandelion, largeflower carveseed
  Gnaphalium L. -- accepted -- cudweed
  Gnaphalium alienum Hook. & Arn. -- not accepted
  Gnaphalium alpinum L. -- not accepted
  Gnaphalium americanum Mill. -- not accepted
  Gnaphalium arizonicum A. Gray -- not accepted
  Gnaphalium arvense L. -- not accepted
  Gnaphalium attenuatum DC. -- not accepted
  Gnaphalium beneolens Davidson -- not accepted
  Gnaphalium bicolor Bioletti -- not accepted
  Gnaphalium brachypterum DC. -- not accepted
  Gnaphalium californicum DC. -- not accepted
  Gnaphalium calviceps Fernald -- not accepted
  Gnaphalium canescens DC. -- not accepted
  Gnaphalium canescens ssp. beneolens (Davidson) Stebbins & Keil -- not accepted
  Gnaphalium canescens ssp. canescens DC. -- not accepted
  Gnaphalium canescens ssp. microcephalum (Nutt.) Stebbins & Keil -- not accepted
  Gnaphalium canescens ssp. thermale (E.E. Nelson) Stebbins & Keil -- not accepted
  Gnaphalium chilense Spreng. -- not accepted
  Gnaphalium chilense var. confertifolium Greene -- not accepted
  Gnaphalium collinum Labill. -- not accepted
  Gnaphalium decurrens Ives, non L. -- not accepted
  Gnaphalium dimorphum Nutt. -- not accepted
  Gnaphalium dioicum L. -- not accepted
  Gnaphalium domingense Lam. -- accepted -- Dominican cudweed
  Gnaphalium elegans Kunth -- not accepted
  Gnaphalium exilifolium A. Nelson -- accepted -- slender cudweed, Gray's cudweed
  Gnaphalium falcatum Lam. -- not accepted
  Gnaphalium germanicum Scop. -- not accepted
  Gnaphalium grayi A. Nelson & J.F. Macbr. -- not accepted
  Gnaphalium gymnocephalus DC. -- not accepted
  Gnaphalium hawaiiense O. Deg. & Sherff -- not accepted
  Gnaphalium helleri Britton -- not accepted
  Gnaphalium helleri var. helleri Britton -- not accepted -- Heller's cudweed
  Gnaphalium helleri var. micradenium (Weath.) Mahler -- not accepted
  Gnaphalium indicum auct. non L. -- not accepted
  Gnaphalium jaliscense Greenm. -- not accepted
  Gnaphalium japonicum Thunb. -- not accepted
  Gnaphalium leucocephalum A. Gray -- not accepted
  Gnaphalium luteoalbum L. -- not accepted
  Gnaphalium macounii Greene -- not accepted
  Gnaphalium margaritaceum L. -- not accepted
  Gnaphalium microcephalum Nutt. -- not accepted
  Gnaphalium microcephalum ssp. thermale (E.E. Nelson) G.W. Douglas -- not accepted
  Gnaphalium microcephalum var. thermale (E.E. Nelson) Cronquist -- not accepted
  Gnaphalium norvegicum Gunnerus -- not accepted -- Norwegian cudweed, gnaphale de Norvčge
  Gnaphalium obtusifolium L. -- not accepted
  Gnaphalium obtusifolium var. helleri (Britton) S.F. Blake -- not accepted
  Gnaphalium obtusifolium var. micradenium Weath. -- not accepted
  Gnaphalium obtusifolium var. obtusifolium L. -- not accepted -- rabbit tobacco
  Gnaphalium obtusifolium var. praecox Fernald -- not accepted
  Gnaphalium obtusifolium var. saxicola (Fassett) Cronquist -- not accepted
  Gnaphalium palustre Nutt. -- accepted -- western marsh cudweed, lowland cudweed, cudweed, marsh everlasting
  Gnaphalium pensylvanicum Willd. -- not accepted
  Gnaphalium peregrinum Fernald -- not accepted
  Gnaphalium plantaginifolium L. -- not accepted
  Gnaphalium polycaulon Pers. -- accepted -- many stem cudweed
  Gnaphalium portoricense Urb. -- not accepted
  Gnaphalium pringlei A. Gray -- not accepted
  Gnaphalium purpureum L. -- not accepted -- catfoot, chafe weed, everlasting, purple cudweed, rabbit tobacco, spoonleaf purple everlasting
  Gnaphalium purpureum var. americanum (Mill.) Klatt -- not accepted
  Gnaphalium purpureum var. falcatum (Lam.) Torr. & A. Gray -- not accepted
  Gnaphalium purpureum var. spathulatum (Lam.) H.E. Ahles -- not accepted
  Gnaphalium purpureum var. ustulatum (Nutt.) B. Boivin -- not accepted
  Gnaphalium ramosissimum Nutt. -- not accepted
  Gnaphalium roseum Kunth -- not accepted
  Gnaphalium sandwicensium Gaudich. -- not accepted
  Gnaphalium sandwicensium var. flagellare Sherff -- not accepted
  Gnaphalium sandwicensium var. hawaiiense (O. Deg. & Sherff) W.L. Wagner, Herbst & Sohmer -- not accepted -- `ena`ena
  Gnaphalium sandwicensium var. kilaueanum O. Deg. & Sherff -- not accepted
  Gnaphalium sandwicensium var. lineatum Sherff -- not accepted
  Gnaphalium sandwicensium var. molokaiense O. Deg. & Sherff -- not accepted
  Gnaphalium sandwicensium var. sandwicensium Gaudich. -- not accepted -- `ena`ena
  Gnaphalium saxicola Fassett -- not accepted
  Gnaphalium spathulatum Lam. -- not accepted
  Gnaphalium sphacilatum Kunth -- not accepted
  Gnaphalium spicatum Lam. -- not accepted
  Gnaphalium stramineum Kunth -- not accepted
  Gnaphalium supinum L. -- not accepted
  Gnaphalium sylvaticum L. -- not accepted
  Gnaphalium thermale E.E. Nelson -- not accepted
  Gnaphalium uliginosum L. -- accepted -- marsh cudweed, low cudweed
  Gnaphalium uliginosum auct. non L. -- not accepted
  Gnaphalium ustulatum Nutt. -- not accepted
  Gnaphalium virgatum L. -- not accepted
  Gnaphalium viscosum Kunth -- not accepted
  Gnaphalium wrightii A. Gray -- not accepted
  Gochnatia Kunth -- accepted -- gochnatia
  Gochnatia hypoleuca (DC.) A. Gray -- accepted -- shrubby bullseye
  Gonotheca helianthoides (L.) Raf. -- not accepted
  Gorteria linearis Thunb. -- not accepted
  Greenella arizonica A. Gray -- not accepted
  Greenella discoidea A. Gray -- not accepted
  Grindelia Willd. -- accepted -- gumweed
  Grindelia acutifolia Steyerm. -- not accepted -- sharpleaf gumweed
  Grindelia adenodonta (Steyerm.) G.L. Nesom -- accepted -- Lonestar gumweed
  Grindelia aphanactis Rydb. -- not accepted
  Grindelia arenicola Steyerm. -- not accepted
  Grindelia arizonica A. Gray -- accepted -- Arizona gumweed, New Mexican gumweed, cutleaf gumweed
  Grindelia arizonica var. arizonica A. Gray -- not accepted -- Arizona gumweed
  Grindelia arizonica var. dentata Steyerm. -- not accepted
  Grindelia arizonica var. microphylla Steyerm. -- not accepted
  Grindelia arizonica var. neomexicana (Woot. & Standl.) G.L. Nesom -- not accepted -- New Mexican gumweed
  Grindelia arizonica var. stenophylla Steyerm. -- not accepted -- Arizona gumweed
  Grindelia camporum Greene -- not accepted -- Great Valley gumweed
  Grindelia camporum var. bracteosa (J.T. Howell) M.A. Lane -- not accepted -- bract gumweed
  Grindelia camporum var. camporum Greene -- not accepted -- Great Valley gumweed
  Grindelia camporum var. parviflora Steyerm. -- not accepted
  Grindelia ciliata (Nutt.) Spreng. -- accepted -- Spanish gold
  Grindelia columbiana (Piper) Rydb. -- not accepted -- Columbia River gumweed
  Grindelia decumbens Greene -- accepted -- reclined gumweed
  Grindelia decumbens var. decumbens Greene -- not accepted -- reclined gumweed
  Grindelia decumbens var. subincisa (Greene) Steyerm. -- not accepted -- reclined gumweed
  Grindelia fastigiata Greene -- not accepted -- pointed gumweed
  Grindelia fraxinipratensis Reveal & Beatley -- accepted -- Ash Meadows gumplant
  Grindelia grandiflora Hook. -- accepted -- manyray gumweed
  Grindelia gymnospermoides (A. Gray) Ruffin -- not accepted
  Grindelia hallii Steyerm. ex Rothr. -- not accepted
  Grindelia havardii Steyerm. -- accepted -- Havard's gumweed
  Grindelia hirsutula Hook. & Arn. -- accepted -- hairy gumweed, sharpleaf gumweed, bract gumweed
  Grindelia hirsutula ssp. hirsutula Hook. & Arn. -- not accepted -- hairy gumweed
  Grindelia hirsutula ssp. rubricaulis (DC.) D.D. Keck -- not accepted
  Grindelia hirsutula var. davyi (Jeps.) M.A. Lane -- not accepted -- hairy gumweed
  Grindelia hirsutula var. hallii (Steyerm. ex Rothr.) M.A. Lane -- not accepted -- Hall's gumweed
  Grindelia hirsutula var. hirsutula Hook. & Arn. -- not accepted -- hairy gumweed
  Grindelia hirsutula var. maritima (Greene) M.A. Lane -- not accepted -- coastal gumweed
  Grindelia howellii Steyerm. -- accepted -- Howell's gumweed
  Grindelia humilis Hook. & Arn. -- not accepted
  Grindelia inornata Greene -- not accepted -- Colorado gumweed
  Grindelia inornata var. angusta Steyerm. -- not accepted -- Colorado gumweed
  Grindelia inornata var. inornata Greene -- not accepted -- Colorado gumweed
  Grindelia integrifolia DC. -- accepted -- Puget Sound gumweed
  Grindelia integrifolia var. integrifolia DC. -- not accepted -- Puget Sound gumweed
  Grindelia integrifolia var. macrophylla (Greene) Cronquist -- not accepted
  Grindelia laciniata Rydb. -- not accepted -- cutleaf gumweed, cut-leaf gumweed
  Grindelia lanceolata Nutt. -- accepted -- narrowleaf gumweed, Texan gumweed, spiny toothed gumweed, Gulf gumweed
  Grindelia lanceolata var. lanceolata Nutt. -- not accepted -- narrowleaf gumweed
  Grindelia lanceolata var. texana (Scheele) Shinners -- not accepted -- Texan gumweed
  Grindelia latifolia Kellogg -- not accepted -- coastal gumweed
  Grindelia latifolia ssp. platyphylla (Greene) D.D. Keck -- not accepted
  Grindelia latifolia var. latifolia Kellogg -- not accepted -- coastal gumweed
  Grindelia latifolia var. platyphylla Greene -- not accepted
  Grindelia littoralis Steyerm. -- not accepted
  Grindelia maritima (Greene) Steyerm. -- not accepted
  Grindelia microcephala DC. -- accepted -- littlehead gumweed
  Grindelia microcephala var. adenodonta Steyerm. -- not accepted
  Grindelia microcephala var. microcephala DC. -- not accepted -- littlehead gumweed
  Grindelia microcephala var. pusilla Steyerm. -- not accepted
  Grindelia nana Nutt. -- not accepted -- Idaho gumweed
  Grindelia nana ssp. columbiana Piper -- not accepted
  Grindelia nana var. discoidea (Nutt.) A. Gray -- not accepted
  Grindelia nana var. integerrima (Rydb.) Steyerm. -- not accepted -- Idaho gumweed
  Grindelia nana var. integrifolia Nutt. -- not accepted
  Grindelia nana var. nana Nutt. -- not accepted -- Idaho gumweed
  Grindelia neomexicana Woot. & Standl. -- not accepted
  Grindelia nuda Alph. Wood -- not accepted -- curlytop gumweed, curly-top gumweed
  Grindelia nuda var. aphanactis (Rydb.) G.L. Nesom -- not accepted -- curlytop gumweed, rayless gumweed
  Grindelia nuda var. nuda Alph. Wood -- not accepted -- curlytop gumweed
  Grindelia oolepis S.F. Blake -- accepted -- plains gumweed
  Grindelia oxylepis Greene -- accepted -- Mexican gumweed
  Grindelia paludosa Greene -- not accepted
  Grindelia papposa G.L. Nesom & Suh -- not accepted -- wax goldenweed, Spanish gold, spanishgold
  Grindelia perennis A. Nelson -- not accepted
  Grindelia procera Greene -- not accepted
  Grindelia pusilla (Steyerm.) G.L. Nesom -- accepted -- little gumweed
  Grindelia revoluta Steyerm. -- not accepted -- rolled gumweed
  Grindelia robusta Nutt. -- not accepted
  Grindelia robusta var. angustifolia A. Gray -- not accepted
  Grindelia robusta var. bracteosa (J.T. Howell) D.D. Keck -- not accepted
  Grindelia robusta var. robusta Nutt. -- not accepted -- shore gumweed
  Grindelia scabra Greene -- accepted -- rough gumweed
  Grindelia scabra var. neomexicana (Woot. & Standl.) Steyerm. -- not accepted
  Grindelia serrulata Rydb. -- not accepted
  Grindelia squarrosa (Pursh) Dunal -- accepted -- curlycup gumweed, curlytop gumweed, gumweed, rosinweed, tarweed
  Grindelia squarrosa var. integrifolia (Nutt.) B. Boivin -- not accepted
  Grindelia squarrosa var. nuda (Alph. Wood) A. Gray -- not accepted
  Grindelia squarrosa var. quasiperennis Lunell -- not accepted -- curlytop gumweed, rosinweed, tarweed, gumweed, curlycup gumweed, curly-cup gumweed
  Grindelia squarrosa var. serrulata (Rydb.) Steyerm. -- not accepted -- gumweed, curlytop gumweed, rosinweed, tarweed, curlycup gumweed, curly-cup gumweed
  Grindelia squarrosa var. squarrosa (Pursh) Dunal -- not accepted -- curlycup gumweed, curly-cup gumweed, curlytop gumweed, rosinweed, tarweed, gumweed
  Grindelia stricta DC. -- not accepted -- Oregon gumweed
  Grindelia stricta ssp. blakei (Steyerm.) D.D. Keck -- not accepted
  Grindelia stricta ssp. venulosa (Jeps.) D.D. Keck -- not accepted
  Grindelia stricta var. angustifolia (A. Gray) M.A. Lane -- not accepted -- Oregon gumweed
  Grindelia stricta var. platyphylla (Greene) M.A. Lane -- not accepted -- Oregon gumweed
  Grindelia stricta var. stricta DC. -- not accepted -- Oregon gumweed
  Grindelia stylosa Eastw. -- not accepted
  Grindelia subalpina Greene -- accepted -- subalpine gumweed
  Grindelia subalpina var. erecta (A. Nelson) Steyerm. -- not accepted -- subalpine gumweed
  Grindelia subalpina var. subalpina Greene -- not accepted -- subalpine gumweed
  Grindelia texana Scheele -- not accepted
  Grindelia texana var. lanceolata (Nutt.) Shinners -- not accepted
  Guardiola Cerv. ex Humb. & Bonpl. -- accepted -- guardiola
  Guardiola platyphylla A. Gray -- accepted -- Apache plant
  Guizotia Cass. -- accepted -- guizotia
  Guizotia abyssinica (L. f.) Cass. -- accepted -- ramtilla
  Gundelia L. -- accepted -- gundelia
  Gundelia tournefortii L. -- accepted -- Tournefort's gundelia
  Gundlachia A. Gray -- accepted -- gundlachia
  Gundlachia corymbosa (Urb.) Britton ex Boldingh -- accepted -- yambush
  Gundlachia triantha (S.F. Blake) Urbatsch & R.P. Roberts -- accepted -- Trans-Pecos desert goldenrod
  Gutierrezia Lag. -- accepted -- snakeweed
  Gutierrezia arizonica (A. Gray) M.A. Lane -- accepted -- Arizona snakeweed
  Gutierrezia bracteata Abrams -- not accepted
  Gutierrezia californica (DC.) Torr. & A. Gray -- accepted -- San Joaquin snakeweed, California snakeweed
  Gutierrezia diversifolia Greene -- not accepted
  Gutierrezia dracunculoides (DC.) S.F. Blake -- not accepted -- prairie broomweed
  Gutierrezia eriocarpa A. Gray -- not accepted
  Gutierrezia glomerella Greene -- not accepted
  Gutierrezia glutinosa (S. Schauer) Sch. Bip. -- not accepted
  Gutierrezia gymnospermoides A. Gray -- not accepted
  Gutierrezia lepidota Greene -- not accepted
  Gutierrezia linearifolia Lag. -- not accepted
  Gutierrezia linearis Rydb. -- not accepted
  Gutierrezia linoides Greene -- not accepted
  Gutierrezia longipappa S.F. Blake -- not accepted
  Gutierrezia lucida (Greene) Greene -- not accepted
  Gutierrezia microcephala (DC.) A. Gray -- accepted -- threadleaf snakeweed
  Gutierrezia petradoria (S.L. Welsh & Goodrich) S.L. Welsh -- accepted -- San Pedro snakeweed
  Gutierrezia polyantha A. Nelson -- not accepted
  Gutierrezia pomariensis (S.L. Welsh) S.L. Welsh -- accepted -- orchard snakeweed
  Gutierrezia sarothrae (Pursh) Britton & Rusby -- accepted -- broom snakeweed, broomweed, perennial snakeweed, stinkweed, turpentine weed, yellow top
  Gutierrezia sarothrae var. microcephala (DC.) L.D. Benson -- not accepted
  Gutierrezia sarothrae var. pomariensis S.L. Welsh -- not accepted
  Gutierrezia serotina Greene -- accepted -- late snakeweed
  Gutierrezia sphaerocephala A. Gray -- accepted -- roundleaf snakeweed, round-leaf snakeweed
  Gutierrezia tenuis Greene -- not accepted
  Gutierrezia texana (DC.) Torr. & A. Gray -- accepted -- Texas snakeweed, Texas broomweed
  Gutierrezia texana var. glutinosa (S. Schauer) M.A. Lane -- accepted -- sticky snakeweed
  Gutierrezia texana var. texana (DC.) Torr. & A. Gray -- accepted -- Texas snakeweed
  Gutierrezia triflora (Rose) M.A. Lane -- not accepted
  Gutierrezia wrightii A. Gray -- accepted -- Wright's snakeweed
  Gymnolomia hispida (A. Gray) B.L. Rob. & Greenm. -- not accepted
  Gymnolomia hispida var. ciliata B.L. Rob. & Greenm. -- not accepted
  Gymnolomia longifolia B.L. Rob. & Greenm. -- not accepted
  Gymnosperma Less. -- accepted -- gymnosperma
  Gymnosperma glutinosum (Spreng.) Less. -- accepted -- gumhead, sticky selloa
  Gymnostyles Juss. -- not accepted -- burrweed, gymnostyles
  Gymnostyles anthemifolia Juss. -- not accepted -- button burrweed
  Gymnostyles nasturtiifolia auct. non Juss. -- not accepted
  Gymnostyles stolonifera (Brot.) Tutin -- not accepted -- carpet burrweed
  Gynura Cass. -- accepted -- gynura
  Gynura aurantiaca (Blume) DC. -- accepted -- velvetplant
  Halea ludoviciana Torr. & A. Gray -- not accepted
  Halea repanda Buckley -- not accepted
  Hamulium alatum (L.) Cass. -- not accepted
  Haplocarpha Less. -- accepted -- onefruit
  Haplocarpha lyrata Harr. -- accepted -- harp onefruit
  Haploesthes A. Gray -- accepted -- false broomweed
  Haploesthes greggii A. Gray -- accepted -- false broomweed
  Haploesthes greggii var. greggii A. Gray -- accepted
  Haploesthes greggii var. texana (J.M. Coult.) I.M. Johnst. -- accepted -- Texas false broomweed, Texas falsebroomweed
  Haplopappus Cass. -- accepted -- haplopappus
  Haplopappus aberrans (A. Nelson) H.M. Hall -- not accepted
  Haplopappus acaulis (Nutt.) A. Gray -- not accepted
  Haplopappus acaulis ssp. typicus H.M. Hall -- not accepted
  Haplopappus acaulis var. glabratus D.C. Eaton -- not accepted
  Haplopappus acradenius (Greene) S.F. Blake -- not accepted
  Haplopappus acradenius ssp. bracteosus (Greene) H.M. Hall -- not accepted
  Haplopappus acradenius ssp. eremophilus (Greene) H.M. Hall -- not accepted
  Haplopappus acradenius var. acradenius (Greene) Blake -- not accepted
  Haplopappus alpigenus Torr. & A. Gray -- not accepted
  Haplopappus alpinus L.C. Anderson & Goodrich -- not accepted
  Haplopappus annuus (Rydb.) Cory -- not accepted
  Haplopappus apargioides A. Gray -- not accepted
  Haplopappus arborescens (A. Gray) H.M. Hall -- not accepted
  Haplopappus armerioides (Nutt.) A. Gray -- not accepted
  Haplopappus armerioides var. gramineus S.L. Welsh & F.J. Sm. -- not accepted
  Haplopappus aureus A. Gray -- not accepted
  Haplopappus blephariphyllus A. Gray -- not accepted
  Haplopappus bloomeri A. Gray -- not accepted
  Haplopappus bloomeri ssp. compactus H.M. Hall -- not accepted
  Haplopappus bloomeri ssp. sonnei (A. Gray) H.M. Hall -- not accepted
  Haplopappus bloomeri var. angustatus A. Gray -- not accepted
  Haplopappus bloomeri var. greenei (A. Gray) Cronquist -- not accepted
  Haplopappus bloomeri var. ophitidis J.T. Howell -- not accepted
  Haplopappus bloomeri var. sonnei (A. Gray) Greene -- not accepted
  Haplopappus brandegeei A. Gray -- not accepted
  Haplopappus brickellioides S.F. Blake -- not accepted
  Haplopappus canus (A. Gray) S.F. Blake -- not accepted
  Haplopappus carthamoides (Hook.) A. Gray -- not accepted
  Haplopappus carthamoides ssp. cusickii (A. Gray) H.M. Hall -- not accepted
  Haplopappus carthamoides ssp. rigidus (Rydb.) H.M. Hall -- not accepted
  Haplopappus carthamoides var. cusickii A. Gray -- not accepted
  Haplopappus carthamoides var. erythropappus (Rydb.) H. St. John -- not accepted
  Haplopappus carthamoides var. maximus A. Gray -- not accepted
  Haplopappus carthamoides var. rigidus (Rydb.) M. Peck -- not accepted
  Haplopappus carthamoides var. subsquarrosus (Greene) Dorn -- not accepted
  Haplopappus carthamoides var. typicus (H.M. Hall) Cronquist -- not accepted
  Haplopappus cervinus S. Watson -- not accepted
  Haplopappus ciliatus (Nutt.) DC. -- not accepted -- Spanish gold, waxed goldenweed
  Haplopappus clementis (Rydb.) S.F. Blake -- not accepted
  Haplopappus coloradoensis (A. Gray) R.L. Hartm. ex Dorn -- not accepted
  Haplopappus compactus (H.M. Hall) L.C. Anderson -- not accepted
  Haplopappus contractus H.M. Hall -- not accepted
  Haplopappus cooperi (A. Gray) H.M. Hall -- not accepted
  Haplopappus coulteri Harv. & A. Gray ex A. Gray -- not accepted
  Haplopappus crispus L.C. Anderson -- not accepted
  Haplopappus croceus A. Gray -- not accepted
  Haplopappus croceus ssp. typicus H.M. Hall -- not accepted
  Haplopappus croceus var. genuflexus (Greene) S.F. Blake -- not accepted
  Haplopappus cuneatus A. Gray -- not accepted
  Haplopappus cuneatus var. spathulatus (A. Gray) S.F. Blake ex Munz -- not accepted
  Haplopappus detonsus (Greene) P.H. Raven -- not accepted
  Haplopappus divaricatus (Nutt.) A. Gray -- not accepted
  Haplopappus divaricatus var. hookerianus (Torr. & A. Gray) Waterf. -- not accepted
  Haplopappus drummondii (Torr. & A. Gray) S.F. Blake -- not accepted
  Haplopappus eastwoodiae H.M. Hall -- not accepted
  Haplopappus engelmannii (A. Gray) H.M. Hall -- not accepted
  Haplopappus ericoides (Less.) Hook. & Arn. -- not accepted
  Haplopappus ericoides ssp. blakei C.B. Wolf -- not accepted
  Haplopappus ericoides var. ericoides (Less.) Hook. & Arn. -- not accepted
  Haplopappus eximius H.M. Hall -- not accepted
  Haplopappus eximius ssp. peirsonii D.D. Keck -- not accepted
  Haplopappus fremontii (A. Gray) Greene -- not accepted
  Haplopappus fremontii ssp. monocephalus (A. Nelson) H.M. Hall -- not accepted
  Haplopappus fremontii ssp. typicus H.M. Hall -- not accepted
  Haplopappus fremontii ssp. wardii (A. Gray) H.M. Hall -- not accepted
  Haplopappus gilmanii S.F. Blake -- not accepted
  Haplopappus gooddingii (A. Nelson) Munz & I.M. Johnst. -- not accepted
  Haplopappus gracilis (Nutt.) A. Gray -- not accepted
  Haplopappus graniticus Tiehm & L.M. Shultz -- not accepted
  Haplopappus greenei A. Gray -- not accepted
  Haplopappus greenei var. mollis A. Gray -- not accepted
  Haplopappus gymnocephalus DC. -- not accepted
  Haplopappus hallii A. Gray -- not accepted
  Haplopappus havardii Waterf. -- not accepted
  Haplopappus heterophyllus (A. Gray) S.F. Blake -- not accepted
  Haplopappus hirtus A. Gray -- not accepted
  Haplopappus hirtus ssp. lanulosus (Greene) H.M. Hall -- not accepted
  Haplopappus hirtus ssp. sonchifolius (Greene) H.M. Hall -- not accepted
  Haplopappus hirtus ssp. typicus H.M. Hall -- not accepted
  Haplopappus hirtus var. lanulosus (Greene) M. Peck -- not accepted
  Haplopappus hirtus var. sonchifolius (Greene) M. Peck -- not accepted
  Haplopappus insecticruris (L.F. Hend.) A. Heller -- not accepted
  Haplopappus integrifolius Porter ex A. Gray -- not accepted
  Haplopappus integrifolius ssp. insecticruris (L.F. Hend.) H.M. Hall -- not accepted
  Haplopappus integrifolius ssp. liatriformis (Greene) H.M. Hall -- not accepted
  Haplopappus integrifolius ssp. scaberulus (Greene) H.M. Hall -- not accepted
  Haplopappus integrifolius ssp. typicus H.M. Hall -- not accepted
  Haplopappus junceus Greene -- not accepted
  Haplopappus lanceolatus (Hook.) Torr. & A. Gray -- not accepted
  Haplopappus lanceolatus ssp. solidagineus (Greene) H.M. Hall -- not accepted
  Haplopappus lanceolatus ssp. tenuicaulis (D.C. Eaton) H.M. Hall -- not accepted
  Haplopappus lanceolatus ssp. vaseyi (Parry ex D.C. Eaton) H.M. Hall -- not accepted
  Haplopappus lanceolatus var. lanceolatus (Hook.) Torr. & A. Gray -- not accepted
  Haplopappus lanceolatus var. sublanatus Cody -- not accepted
  Haplopappus lanceolatus var. tenuicaulis (D.C. Eaton) A. Gray -- not accepted
  Haplopappus lanceolatus var. typicus (H.M. Hall) Cronquist -- not accepted
  Haplopappus lanceolatus var. vaseyi Parry ex D.C. Eaton -- not accepted
  Haplopappus lanuginosus A. Gray -- not accepted
  Haplopappus lanuginosus ssp. andersonii (Rydb.) H.M. Hall -- not accepted
  Haplopappus lanuginosus ssp. typicus H.M. Hall -- not accepted
  Haplopappus lanuginosus var. andersonii (Rydb.) Cronquist -- not accepted
  Haplopappus lanulosus (Greene) M. Peck -- not accepted
  Haplopappus laricifolius A. Gray -- not accepted
  Haplopappus leverichii Cronquist -- not accepted
  Haplopappus liatriformis (Greene) H. St. John -- not accepted
  Haplopappus lignumviridis S.L. Welsh -- not accepted
  Haplopappus linearifolius DC. -- not accepted
  Haplopappus linearifolius ssp. interior (Coville) H.M. Hall -- not accepted
  Haplopappus linearifolius var. interior (Coville) M.E. Jones -- not accepted
  Haplopappus lucidus (D.D. Keck) D.D. Keck -- not accepted
  Haplopappus lyallii A. Gray -- not accepted
  Haplopappus macleanii Brandegee -- not accepted
  Haplopappus macronema (Nutt.) A. Gray -- not accepted
  Haplopappus macronema var. canescens (A. Nelson) Cronquist -- not accepted
  Haplopappus macronema var. linearis (Rydb.) Dorn -- not accepted
  Haplopappus macronema var. typicus H.M. Hall -- not accepted
  Haplopappus microcephalus Cronquist -- not accepted
  Haplopappus multicaulis (Nutt.) A. Gray -- not accepted
  Haplopappus nanus (Nutt.) D.C. Eaton -- not accepted
  Haplopappus nuttallii Torr. & A. Gray -- not accepted
  Haplopappus nuttallii var. depressus Maguire -- not accepted
  Haplopappus ophitidis (J.T. Howell) D.D. Keck -- not accepted
  Haplopappus palmeri A. Gray -- not accepted
  Haplopappus palmeri ssp. pachylepis H.M. Hall -- not accepted
  Haplopappus paniculatus var. virgatus A. Gray -- not accepted
  Haplopappus parishii (Greene) S.F. Blake -- not accepted
  Haplopappus parryi A. Gray -- not accepted
  Haplopappus peirsonii (D.D. Keck) J.T. Howell -- not accepted
  Haplopappus phyllocephalus DC. -- not accepted
  Haplopappus phyllocephalus ssp. annuus (Rydb.) H.M. Hall -- not accepted
  Haplopappus phyllocephalus var. annuus (Rydb.) Waterf. -- not accepted
  Haplopappus phyllocephalus var. megacephalus (Nash) Waterf. -- not accepted
  Haplopappus pinifolius A. Gray -- not accepted
  Haplopappus pluriflorus (Torr. & A. Gray) H.M. Hall -- not accepted
  Haplopappus propinquus S.F. Blake -- not accepted
  Haplopappus pygmaeus (Torr. & A. Gray) A. Gray -- not accepted
  Haplopappus racemosus (Nutt.) Torr. -- not accepted
  Haplopappus racemosus ssp. brachycephalus (A. Nelson) H.M. Hall -- not accepted
  Haplopappus racemosus ssp. congestus (Greene) H.M. Hall -- not accepted
  Haplopappus racemosus ssp. duriuscula (Greene) H.M. Hall -- not accepted
  Haplopappus racemosus ssp. glomeratus (Nutt.) H.M. Hall -- not accepted
  Haplopappus racemosus ssp. halophilus (Greene) H.M. Hall -- not accepted
  Haplopappus racemosus ssp. liatriformis (Greene) D.D. Keck -- not accepted
  Haplopappus racemosus ssp. lucidus D.D. Keck -- not accepted
  Haplopappus racemosus ssp. pinetorum D.D. Keck -- not accepted
  Haplopappus racemosus ssp. prionophyllus (Greene) H.M. Hall -- not accepted
  Haplopappus racemosus ssp. sessiliflorus (Greene) H.M. Hall -- not accepted
  Haplopappus racemosus var. glomerellus (Nutt.) A. Gray -- not accepted
  Haplopappus racemosus var. paniculatus (Nutt.) Cronquist -- not accepted
  Haplopappus racemosus var. prionophyllus (Greene) S.L. Welsh -- not accepted
  Haplopappus racemosus var. racemosus (Nutt.) Torr. -- not accepted
  Haplopappus racemosus var. sessiliflorus (Greene) S.L. Welsh -- not accepted
  Haplopappus radiatus (Nutt.) Cronquist -- not accepted
  Haplopappus ravenii R.C. Jacks. -- not accepted
  Haplopappus resinosus (Nutt.) A. Gray -- not accepted
  Haplopappus rigidifolius E.B. Sm. -- not accepted
  Haplopappus rusbyi (Greene) Cronquist -- not accepted
  Haplopappus rydbergii S.F. Blake -- not accepted
  Haplopappus salicinus S.F. Blake -- not accepted
  Haplopappus scopulorum (M.E. Jones) S.F. Blake -- not accepted
  Haplopappus scopulorum var. hirtellus S.F. Blake -- not accepted
  Haplopappus spinulosus (Pursh) DC. -- not accepted -- cutleaf ironplant, ironplant, lacy tansyaster
  Haplopappus spinulosus ssp. australis (Greene) H.M. Hall -- not accepted
  Haplopappus spinulosus ssp. cotula (Small) H.M. Hall -- not accepted
  Haplopappus spinulosus ssp. glaberrimus (Rydb.) H.M. Hall -- not accepted
  Haplopappus spinulosus ssp. laevis (Woot. & Standl.) H.M. Hall -- not accepted
  Haplopappus spinulosus ssp. scabrellus (Greene) H.M. Hall -- not accepted
  Haplopappus spinulosus var. canescens A. Gray -- not accepted
  Haplopappus spinulosus var. chihuahuanus (B.L. Turner & R.L. Hartm.) Gandhi -- not accepted
  Haplopappus spinulosus var. glaber A. Gray -- not accepted
  Haplopappus spinulosus var. glaberrimus (Rydb.) S.F. Blake -- not accepted
  Haplopappus spinulosus var. gooddingii (A. Nelson) S.F. Blake -- not accepted
  Haplopappus spinulosus var. paradoxa (B.L. Turner & R.L. Hartm.) Cronquist -- not accepted
  Haplopappus spinulosus var. scabrellus (Greene) S.F. Blake -- not accepted
  Haplopappus spinulosus var. turbinellus (Rydb.) S.F. Blake -- not accepted
  Haplopappus squarrosus Hook. & Arn. -- not accepted
  Haplopappus squarrosus ssp. grindelioides (DC.) D.D. Keck -- not accepted
  Haplopappus squarrosus ssp. obtusus (Greene) H.M. Hall -- not accepted
  Haplopappus squarrosus ssp. stenolepis H.M. Hall -- not accepted
  Haplopappus squarrosus var. squarrosus Hook. & Arn. -- not accepted
  Haplopappus stenophyllus A. Gray -- not accepted
  Haplopappus subviscosus (Greene) S.F. Blake -- not accepted
  Haplopappus suffruticosus (Nutt.) A. Gray -- not accepted
  Haplopappus tenuisectus (Greene) S.F. Blake -- not accepted
  Haplopappus texensis R.C. Jacks. -- not accepted
  Haplopappus trianthus S.F. Blake -- not accepted
  Haplopappus uniflorus (Hook.) Torr. & A. Gray -- not accepted
  Haplopappus uniflorus ssp. gossypinus (Greene) H.M. Hall -- not accepted
  Haplopappus uniflorus ssp. howellii (A. Gray) H.M. Hall -- not accepted
  Haplopappus uniflorus ssp. linearis D.D. Keck -- not accepted
  Haplopappus uniflorus ssp. typicus H.M. Hall -- not accepted
  Haplopappus uniflorus var. howellii (A. Gray) M. Peck -- not accepted
  Haplopappus uniflorus var. uniflorus (Hook.) Torr. & A. Gray -- not accepted
  Haplopappus validus (Rydb.) Cory -- not accepted
  Haplopappus validus ssp. graniticus E.B. Sm. -- not accepted
  Haplopappus validus ssp. torreyi E.B. Sm. -- not accepted
  Haplopappus venetus (Kunth) S.F. Blake -- not accepted
  Haplopappus venetus ssp. furfuraceus (Greene) H.M. Hall -- not accepted
  Haplopappus venetus ssp. oxyphyllus (Greene) H.M. Hall -- not accepted
  Haplopappus venetus ssp. vernonioides (Nutt.) H.M. Hall -- not accepted
  Haplopappus venetus var. argutus (Greene) D.D. Keck -- not accepted
  Haplopappus venetus var. sedoides (Greene) Munz -- not accepted
  Haplopappus venetus var. venetus (Kunth) S.F. Blake -- not accepted
  Haplopappus wardii (A. Gray) Dorn -- not accepted
  Haplopappus watsonii A. Gray -- not accepted
  Haplopappus watsonii var. rydbergii (S.F. Blake) S.L. Welsh -- not accepted
  Haplopappus whitneyi A. Gray -- not accepted
  Haplopappus whitneyi ssp. discoideus (J.T. Howell) D.D. Keck -- not accepted
  Haplopappus whitneyi var. whitneyi A. Gray -- not accepted
  Haplopappus zionis L.C. Anderson -- not accepted
  Harmonia B.G. Baldw. -- accepted
  Harmonia doris-nilesiae (T.W. Nelson & J.P. Nelson) B.G. Baldw. -- accepted -- serpentine tarweed
  Harmonia guggolziorum B.G. Baldw. -- accepted
  Harmonia hallii (D.D. Keck) B.G. Baldw. -- accepted -- Hall's madia
  Harmonia nutans (Greene) B.G. Baldw. -- accepted -- nodding madia
  Harmonia stebbinsii (T.W. Nelson & J.P. Nelson) B.G. Baldw. -- accepted -- Stebbins' tarweed
  Hartwrightia A. Gray ex S. Watson -- accepted -- hartwrightia
  Hartwrightia floridana A. Gray ex S. Watson -- accepted -- Florida hartwrightia
  Hasteola Raf. -- accepted -- false Indian plantain, false Indian plaintain
  Hasteola robertiorum L.C. Anderson -- accepted -- hammockherb
  Hasteola suaveolens (L.) Pojark. -- not accepted
  Hazardia Greene -- accepted -- bristleweed, hazardia
  Hazardia brickellioides (S.F. Blake) W.D. Clark -- accepted -- brickellbush goldenweed, brickelbush goldenweed
  Hazardia cana (A. Gray) Greene -- accepted -- island hazardia
  Hazardia detonsa (Greene) Greene -- accepted -- island bristleweed
  Hazardia orcuttii (A. Gray) Greene -- accepted -- Orcutt's bristleweed, Orcutt's hazardia
  Hazardia squarrosa (Hook. & Arn.) Greene -- accepted -- sawtooth goldenbush
  Hazardia squarrosa var. grindelioides (DC.) W.D. Clark -- accepted -- sawtooth bristleweed
  Hazardia squarrosa var. obtusa (Greene) Jeps. -- accepted -- sawtooth bristleweed
  Hazardia squarrosa var. squarrosa (Hook. & Arn.) Greene -- accepted -- sawtooth goldenbush
  Hazardia stenolepis (H.M. Hall) Hoover -- accepted -- serpentine bristleweed
  Hazardia whitneyi (A. Gray) Greene -- accepted -- Whitney's bristleweed
  Hazardia whitneyi var. discoidea (J.T. Howell) W.D. Clark -- accepted -- Whitney's bristleweed
  Hazardia whitneyi var. whitneyi (A. Gray) Greene -- accepted -- Whitney's bristleweed
  Hebeclinium DC. -- accepted -- thoroughwort
  Hebeclinium macrophyllum (L) DC -- accepted -- largeleaf thoroughwort
  Hecastocleis A. Gray -- accepted -- hecastocleis
  Hecastocleis shockleyi A. Gray -- accepted -- prickleleaf
  Hedosyne Strother -- accepted
  Hedosyne ambrosiifolia (A. Gray) Strother -- accepted -- ragged marsh-elder
  Hedypnois Mill. -- accepted -- hedypnois
  Hedypnois cretica (L.) Dum. Cours. -- accepted -- Cretanweed
  Heleastrum hemisphericum (Alexander) Shinners -- not accepted
  Helenium L. -- accepted -- sneezeweed
  Helenium amarum (Raf.) H. Rock -- accepted -- yellowdicks, bitter sneezeweed
  Helenium amarum var. amarum (Raf.) H. Rock -- accepted -- yellowdicks
  Helenium amarum var. badium (A. Gray ex S. Watson) Waterf. -- accepted -- yellowdicks, basin sneezeweed
  Helenium amphilobum A. Gray -- not accepted
  Helenium apterum (S.F. Blake) Bierner -- accepted
  Helenium arizonicum S.F. Blake -- accepted -- Arizona sneezeweed
  Helenium autumnale L. -- accepted -- common sneezeweed, fall sneezeweed, mountain sneezeweed, bitterweed, false sunflower
  Helenium autumnale var. autumnale L. -- not accepted -- common sneezeweed
  Helenium autumnale var. canaliculatum (Lam.) Torr. & A. Gray -- not accepted
  Helenium autumnale var. fylesii Boivin -- not accepted -- Fyles' sneezeweed
  Helenium autumnale var. grandiflorum (Nutt.) Torr. & A. Gray -- not accepted -- fall sneezeweed
  Helenium autumnale var. montanum (Nutt.) Fernald -- not accepted -- mountain sneezeweed
  Helenium autumnale var. parviflorum (Nutt.) Fernald -- not accepted -- smallflower sneezeweed
  Helenium badium (A. Gray ex S. Watson) Greene -- not accepted
  Helenium bigelovii A. Gray -- accepted -- Bigelow's sneezeweed
  Helenium bigelovii var. festivum Jeps. -- not accepted
  Helenium bolanderi A. Gray -- accepted -- coastal sneezeweed
  Helenium brevifolium (Nutt.) Alph. Wood -- accepted -- shortleaf sneezeweed
  Helenium campestre Small -- accepted -- oldfield sneezeweed
  Helenium canaliculatum Lam. -- not accepted
  Helenium curtisii A. Gray -- not accepted
  Helenium decurrens (Less.) Vatke, non Moench -- not accepted
  Helenium drummondii H. Rock -- accepted -- fringed sneezeweed
  Helenium elegans DC. -- accepted -- pretty sneezeweed
  Helenium elegans var. amphilobum (A. Gray) Bierner -- accepted -- pretty sneezeweed
  Helenium elegans var. elegans DC. -- accepted -- pretty sneezeweed
  Helenium fimbriatum auct. non (Michx.) Eaton -- not accepted
  Helenium flexuosum Raf. -- accepted -- purplehead sneezeweed
  Helenium floridanum Fernald -- not accepted
  Helenium godfreyi Fernald -- not accepted
  Helenium helenium (Nutt.) Small -- not accepted
  Helenium hoopesii A. Gray -- not accepted
  Helenium incisum (Torr. & A. Gray) Alph. Wood -- not accepted
  Helenium lanciniatum A. Gray -- accepted
  Helenium latifolium Mill. -- not accepted
  Helenium linifolium Rydb. -- accepted -- slimleaf sneezeweed
  Helenium macranthum Rydb. -- not accepted
  Helenium microcephalum DC. -- accepted -- smallhead sneezeweed, littlehead tarweed
  Helenium microcephalum var. microcephalum DC. -- accepted -- smallhead sneezeweed
  Helenium microcephalum var. ooclinium (A. Gray) Bierner -- accepted -- smallhead sneezeweed
  Helenium montanum Nutt. -- not accepted
  Helenium nudiflorum Nutt. -- not accepted
  Helenium nuttallii A. Gray -- not accepted
  Helenium ooclinium A. Gray -- not accepted
  Helenium parviflorum Nutt. -- not accepted
  Helenium pinnatifidum (Nutt.) Rydb. -- accepted -- southeastern sneezeweed
  Helenium puberulum DC. -- accepted -- rosilla
  Helenium quadridentatum Labill. -- accepted -- longdisk sneezeweed
  Helenium rivulare (Greene) Rydb. -- not accepted
  Helenium setigerum (DC.) Britton & Rusby -- not accepted
  Helenium tenuifolium Nutt. -- not accepted
  Helenium tenuifolium var. badium A. Gray ex S. Watson -- not accepted
  Helenium thurberi A. Gray -- accepted -- Thurber's sneezeweed
  Helenium vernale auct. non Walter -- not accepted -- savannah sneezeweed
  Helenium vernale Walter -- accepted -- savannah sneezeweed
  Helenium virginicum S.F. Blake -- accepted -- Virginia sneezeweed
  Helenium X polyphyllum Small (pro sp.) -- accepted -- sneezeweed
  Helianthella Torr. & A. Gray -- accepted -- helianthella
  Helianthella californica A. Gray -- accepted -- California helianthella
  Helianthella californica ssp. californica A. Gray -- accepted -- California helianthella
  Helianthella californica ssp. nevadensis (Greene) W.A. Weber -- accepted -- Nevada helianthella
  Helianthella californica ssp. shastensis (W.A. Weber) W.A. Weber -- accepted -- Shasta helianthella
  Helianthella californica var. californica A. Gray -- not accepted -- California helianthella
  Helianthella californica var. nevadensis (Greene) Jeps. -- not accepted -- Nevada helianthella
  Helianthella californica var. shastensis W.A. Weber -- not accepted -- Shasta helianthella
  Helianthella castanea Greene -- accepted -- Mt. Diablo helianthella
  Helianthella covillei A. Nelson -- not accepted
  Helianthella grandiflora Torr. & A. Gray -- not accepted
  Helianthella microcephala (A. Gray) A. Gray -- accepted -- purpledisk helianthella, small-head dwarf-sunflower
  Helianthella parryi A. Gray -- accepted -- Parry's dwarf-sunflower, Parry's dwarfsunflower
  Helianthella pringlei A. Gray -- not accepted
  Helianthella quinquenervis (Hook.) A. Gray -- accepted -- fivenerve helianthella, nodding dwarf-sunflower, nodding helianthella
  Helianthella tenuifolia Torr. & A. Gray -- not accepted
  Helianthella uniflora (Nutt.) Torr. & A. Gray -- accepted -- oneflower helianthella
  Helianthella uniflora var. douglasii (Torr. & A. Gray) W.A. Weber -- not accepted -- Douglas' helianthella
  Helianthella uniflora var. uniflora (Nutt.) Torr. & A. Gray -- not accepted -- oneflower helianthella
  Helianthus L. -- accepted -- sunflower
  Helianthus agrestis Pollard -- accepted -- southeastern sunflower
  Helianthus alienus E.E. Watson -- not accepted
  Helianthus angustifolius L. -- accepted -- swamp sunflower, swamp sneezeweed
  Helianthus angustifolius var. planifolius Fernald -- not accepted
  Helianthus annuus L. -- accepted -- common sunflower, sunflower, wild sunflower, annual sunflower
  Helianthus annuus ssp. jaegeri (Heiser) Heiser -- not accepted
  Helianthus annuus ssp. lenticularis (Douglas ex Lindl.) Cockerell -- not accepted
  Helianthus annuus ssp. texanus Heiser -- not accepted
  Helianthus annuus var. lenticularis (Douglas ex Lindl.) Steyerm. -- not accepted
  Helianthus annuus var. macrocarpus (DC.) Cockerell -- not accepted
  Helianthus annuus var. texanus (Heiser) Shinners -- not accepted
  Helianthus anomalus S.F. Blake -- accepted -- western sunflower, desert sunflower
  Helianthus argophyllus Torr. & A. Gray -- accepted -- silverleaf sunflower
  Helianthus aridus Rydb. -- not accepted
  Helianthus aristatus Elliot -- not accepted
  Helianthus arizonensis R.C. Jacks. -- accepted -- Arizona sunflower
  Helianthus atrorubens L. -- accepted -- purpledisk sunflower
  Helianthus atrorubens var. alsodes Fernald -- not accepted
  Helianthus atrorubens var. pubescens Kuntze -- not accepted
  Helianthus bolanderi A. Gray -- accepted -- serpentine sunflower
  Helianthus borealis E.E. Watson -- not accepted
  Helianthus californicus DC. -- accepted -- California sunflower
  Helianthus canescens (A. Gray) S. Watson -- not accepted
  Helianthus canus (Britton) Woot. & Standl. -- not accepted
  Helianthus carnosus Small -- accepted -- lakeside sunflower
  Helianthus ciliaris DC. -- accepted -- Texas blueweed, blueweed, yerba parda, blueweed sunflower, Texas-blueweed
  Helianthus cinereus var. sullivantii Torr. & A. Gray -- not accepted
  Helianthus couplandii Boivin -- not accepted -- Coupland's sunflower
  Helianthus crenatus R.C. Jacks. -- not accepted
  Helianthus cucumerifolius Torr. & A. Gray -- not accepted
  Helianthus cusickii A. Gray -- accepted -- Cusick's sunflower
  Helianthus dalyi Britton -- not accepted
  Helianthus debilis Nutt. -- accepted -- cucumberleaf sunflower
  Helianthus debilis ssp. cucumerifolius (Torr. & A. Gray) Heiser -- accepted -- cucumberleaf sunflower
  Helianthus debilis ssp. debilis Nutt. -- accepted -- cucumberleaf sunflower
  Helianthus debilis ssp. hirtus Heiser -- not accepted
  Helianthus debilis ssp. praecox (Engelm. & A. Gray) Heiser -- not accepted
  Helianthus debilis ssp. runyonii Heiser -- not accepted
  Helianthus debilis ssp. silvestris Heiser -- accepted -- cucumberleaf sunflower
  Helianthus debilis ssp. tardiflorus Heiser -- accepted -- cucumberleaf sunflower
  Helianthus debilis ssp. vestitus (E.E. Watson) Heiser -- accepted -- cucumberleaf sunflower
  Helianthus debilis var. cucumerifolius (Torr. & A. Gray) A. Gray -- not accepted
  Helianthus debilis var. silvestris (Heiser) Cronquist -- not accepted
  Helianthus debilis var. tardiflorus (Heiser) Cronquist -- not accepted
  Helianthus debilis var. vestitus (E.E. Watson) Cronquist -- not accepted
  Helianthus decapetalus L. -- accepted -- thinleaf sunflower
  Helianthus dentatus Cav. -- not accepted
  Helianthus deserticola Heiser -- accepted -- desert sunflower
  Helianthus divaricatus L. -- accepted -- woodland sunflower, hélianthe ŕ feuilles étalées
  Helianthus divaricatus var. angustifolius Kuntze -- not accepted
  Helianthus dowellianus M.A. Curtis -- not accepted
  Helianthus eggertii Small -- accepted -- Eggert's sunflower
  Helianthus exilis A. Gray -- accepted -- serpentine sunflower
  Helianthus fascicularis Greene -- not accepted
  Helianthus filiformis Small -- not accepted
  Helianthus floridanus A. Gray ex Chapm. -- accepted -- Florida sunflower
  Helianthus giganteus L. -- accepted -- giant sunflower
  Helianthus giganteus ssp. alienus (E.E. Watson) R.W. Long -- not accepted
  Helianthus giganteus var. subtuberosus Britton -- not accepted
  Helianthus glaucophyllus D.M. Sm. -- accepted -- whiteleaf sunflower
  Helianthus gracilentus A. Gray -- accepted -- slender sunflower
  Helianthus grosseserratus M. Martens -- accepted -- sawtooth sunflower, saw-tooth sunflower
  Helianthus grosseserratus ssp. maximus R.W. Long -- not accepted
  Helianthus grosseserratus var. hypoleucus A. Gray -- not accepted
  Helianthus heiseri R.C. Jacks. -- not accepted
  Helianthus heterophyllus Nutt. -- accepted -- variableleaf sunflower
  Helianthus hirsutus Raf. -- accepted -- hairy sunflower
  Helianthus hirsutus var. stenophyllus Torr. & A. Gray -- not accepted
  Helianthus hirsutus var. trachyphyllus Torr. & A. Gray -- not accepted
  Helianthus instabilis E.E. Watson -- not accepted
  Helianthus laciniatus A. Gray -- accepted -- alkali sunflower
  Helianthus laetiflorus var. rigidus (Cass.) Fernald -- not accepted
  Helianthus laetiflorus var. subrhomboideus (Rydb.) Fernald -- not accepted
  Helianthus laevigatus Torr. & A. Gray -- accepted -- smooth sunflower
  Helianthus laevis L. -- not accepted
  Helianthus lenticularis Douglas ex Lindl. -- not accepted
  Helianthus longifolius Pursh -- accepted -- longleaf sunflower
  Helianthus ludens Shinners -- not accepted
  Helianthus maximiliani Schrad. -- accepted -- Maximilian sunflower
  Helianthus microcephalus Torr. & A. Gray -- accepted -- small woodland sunflower
  Helianthus mollis Lam. -- accepted -- ashy sunflower
  Helianthus mollis var. cordatus S. Watson -- not accepted
  Helianthus montanus E.E. Watson -- not accepted
  Helianthus neglectus Heiser -- accepted -- neglected sunflower
  Helianthus niveus (Benth.) Brandegee -- accepted -- showy sunflower, snowy sunflower
  Helianthus niveus ssp. canescens (A. Gray) Heiser -- not accepted -- showy sunflower
  Helianthus niveus ssp. niveus (Benth.) Brandegee -- accepted
  Helianthus niveus ssp. tephrodes (A. Gray) Heiser -- accepted -- Algodones sunflower
  Helianthus nuttallii Torr. & A. Gray -- accepted -- Nuttall's sunflower
  Helianthus nuttallii ssp. canadensis R.W. Long -- not accepted
  Helianthus nuttallii ssp. coloradensis (Cockerell) R.W. Long -- not accepted
  Helianthus nuttallii ssp. nuttallii Torr. & A. Gray -- accepted -- Nuttall's sunflower
  Helianthus nuttallii ssp. parishii (A. Gray) Heiser -- accepted -- Parish's sunflower
  Helianthus nuttallii ssp. rydbergii (Britton) R.W. Long -- accepted -- Rydberg's sunflower
  Helianthus nuttallii var. rydbergii (Britton) B. Boivin -- not accepted
  Helianthus nuttallii var. subtuberosus (Britton) B. Boivin -- not accepted
  Helianthus occidentalis Riddell -- accepted -- fewleaf sunflower
  Helianthus occidentalis ssp. occidentalis Riddell -- accepted -- fewleaf sunflower
  Helianthus occidentalis ssp. plantagineus (Torr. & A. Gray) Shinners -- accepted -- fewleaf sunflower, Gewleaf sunflower
  Helianthus occidentalis var. dowellianus (M.A. Curtis) Torr. & A. Gray -- not accepted
  Helianthus occidentalis var. plantagineus Torr. & A. Gray -- not accepted
  Helianthus orgyalis DC. -- not accepted
  Helianthus paradoxus Heiser -- accepted -- paradox sunflower, puzzle sunflower, Pecos sunflower
  Helianthus parishii A. Gray -- not accepted
  Helianthus pauciflorus Nutt. -- accepted -- stiff sunflower
  Helianthus pauciflorus ssp. pauciflorus Nutt. -- accepted -- stiff sunflower
  Helianthus pauciflorus ssp. subrhomboideus (Rydb.) O. Spring & E.E. Schill. -- accepted -- stiff sunflower
  Helianthus pauciflorus var. subrhomboideus (Rydb.) Cronquist -- not accepted
  Helianthus petiolaris Nutt. -- accepted -- prairie sunflower, showy sunflower
  Helianthus petiolaris ssp. fallax Heiser -- accepted -- prairie sunflower
  Helianthus petiolaris ssp. petiolaris Nutt. -- accepted -- prairie sunflower
  Helianthus petiolaris var. canescens A. Gray -- not accepted
  Helianthus petiolaris var. fallax (Heiser) B.L. Turner -- not accepted
  Helianthus pilosus Tausch -- not accepted
  Helianthus porteri (A. Gray) Pruski -- accepted -- Porter's sunflower
  Helianthus praecox Engelm. & A. Gray -- accepted -- Texas sunflower
  Helianthus praecox ssp. hirtus (Heiser) Heiser -- accepted -- Texas sunflower
  Helianthus praecox ssp. praecox Engelm. & A. Gray -- accepted -- Texas sunflower
  Helianthus praecox ssp. runyonii (Heiser) Heiser -- accepted -- Runyon's sunflower
  Helianthus praecox var. runyonii (Heiser) B.L. Turner -- not accepted
  Helianthus praetermissus E.E. Watson -- accepted -- New Mexico sunflower
  Helianthus pumilus Nutt. -- accepted -- little sunflower
  Helianthus quinquenervis Hook. -- not accepted
  Helianthus radula (Pursh) Torr. & A. Gray -- accepted -- rayless sunflower, stiff sunflower
  Helianthus reindutus (Steele) E.E. Watson -- not accepted
  Helianthus resinosus Small -- accepted -- resindot sunflower
  Helianthus rigidus (Cass.) Desf. -- not accepted
  Helianthus rigidus ssp. laetiflorus (Rydb.) Heiser -- not accepted
  Helianthus rigidus ssp. subrhomboideus (Rydb.) Heiser -- not accepted
  Helianthus rigidus var. rigidus (Cass.) Desf. -- not accepted
  Helianthus rigidus var. subrhomboideus (Rydb.) Cronquist -- not accepted
  Helianthus rydbergii Britton -- not accepted
  Helianthus salicifolius A. Dietr. -- accepted -- willowleaf sunflower
  Helianthus saxicola Small -- not accepted
  Helianthus scaberrimus Elliot -- not accepted
  Helianthus schweinitzii Torr. & A. Gray -- accepted -- Schweinitz's sunflower
  Helianthus scrophulariifolius Britton -- not accepted
  Helianthus silphioides Nutt. -- accepted -- rosinweed sunflower
  Helianthus simulans E.E. Watson -- accepted -- muck sunflower
  Helianthus smithii Heiser -- accepted -- Smith's sunflower
  Helianthus stenophyllus (Torr. & A. Gray) E.E. Watson -- not accepted
  Helianthus strumosus L. -- accepted -- paleleaf woodland sunflower
  Helianthus subrhomboideus Rydb. -- not accepted
  Helianthus subtuberosus (Britton) Britton -- not accepted
  Helianthus tephrodes A. Gray -- not accepted
  Helianthus tomentosus auct. non Michx. -- not accepted
  Helianthus tomentosus Michx. -- not accepted
  Helianthus tracheliifolius Mill. -- not accepted
  Helianthus tuberosus L. -- accepted -- Jerusalem artichoke, girasole, Jerusalem sunflower, Jerusalem-artichoke
  Helianthus tuberosus var. subcanescens A. Gray -- not accepted
  Helianthus uniflorus Nutt. -- not accepted
  Helianthus validus E.E. Watson -- not accepted
  Helianthus verticillatus Small -- accepted -- whorled sunflower
  Helianthus vestitus E.E. Watson -- not accepted
  Helianthus X alexidis Boivin -- not accepted -- Alex sunflower
  Helianthus X ambiguus (A. Gray) Britton (pro sp.) -- accepted -- ambiguous sunflower
  Helianthus X brevifolius E.E. Watson (pro sp.) -- accepted -- shortleaf sunflower
  Helianthus X cinereus Torr. & A. Gray (pro sp.) -- accepted -- sunflower
  Helianthus X divariserratus R.W. Long -- accepted -- sunflower
  Helianthus X doronicoides Lam. (pro sp.) -- accepted -- sunflower, perennial sunflower
  Helianthus X glaucus Small (pro sp.) -- accepted -- glaucous sunflower
  Helianthus X intermedius R.W. Long -- accepted -- intermediate sunflower
  Helianthus X kellermanii Britton (pro sp.) -- accepted -- Kellerman's sunflower
  Helianthus X laetiflorus Pers. (pro sp.) -- accepted -- cheerful sunflower, mountain sunflower
  Helianthus X luxurians E.E. Watson (pro sp.) -- accepted -- luxuriant sunflower
  Helianthus X multiflorus L. (pro sp.) -- accepted -- manyflower sunflower
  Helianthus X orgyaloides Cockerell (pro sp.) -- accepted -- sunflower
  Helianthus X verticillatus E.E. Watson (pro sp.) -- accepted -- sunflower
  Helichrysum Mill. -- accepted -- strawflower
  Helichrysum bracteatum (Vent.) Andrews -- not accepted -- bracted strawflower
  Helichrysum foetidum (L.) Cass. -- accepted -- stinking strawflower
  Helichrysum formosissimum Sch. Bip. -- accepted -- everlasting-flower
  Helichrysum petiolare Hilliard & B.L. Burtt -- accepted -- licorice-plant, licorice plant
  Helichrysum petiolatum (L) DC -- not accepted
  Heliomeris Nutt. -- accepted -- false goldeneye, heliomeris
  Heliomeris annua (M.E. Jones) Cockerell -- not accepted
  Heliomeris ciliata (B.L. Rob. & Greenm.) Yates -- not accepted -- hairy false goldeneye, hairy falsegoldeneye
  Heliomeris hispida (A. Gray) Cockerell -- accepted -- rough false goldeneye, hairy falsegoldeneye
  Heliomeris longifolia (B.L. Rob. & Greenm.) Cockerell -- accepted -- longleaf false goldeneye, longleaf falsegoldeneye, longleaf falsegoldeneyes
  Heliomeris longifolia var. annua (M.E. Jones) Yates -- accepted -- longleaf false goldeneye, annual goldeneye, longleaf falsegoldeneye
  Heliomeris longifolia var. longifolia (B.L. Rob. & Greenm.) Cockerell -- accepted -- longleaf false goldeneye
  Heliomeris multiflora Nutt. -- accepted -- showy goldeneye, showy goldeneyes
  Heliomeris multiflora var. brevifolia (Greene ex Woot. & Standl.) Yates -- accepted -- showy goldeneye
  Heliomeris multiflora var. macrocephala Heiser -- accepted
  Heliomeris multiflora var. multiflora Nutt. -- accepted -- showy goldeneye, showy goldeneyes
  Heliomeris multiflora var. nevadensis (A. Nelson) Yates -- accepted -- Nevada goldeneye, Nevada goldeneyes
  Heliomeris porteri (A. Gray) Cockerell -- not accepted
  Heliomeris soliceps (Barneby) Yates -- accepted -- tropical false goldeneye
  Heliomeris tenuifolia A. Gray -- not accepted
  Heliopsis Pers. -- accepted -- heliopsis
  Heliopsis gracilis Nutt. -- accepted -- smooth oxeye
  Heliopsis helianthoides (L.) Sweet -- accepted -- smooth oxeye, heliopsis sunflower, oxeye, sunflower heliopsis
  Heliopsis helianthoides ssp. occidentalis T.R. Fisher -- not accepted
  Heliopsis helianthoides ssp. scabra (Dunal) T.R. Fisher -- not accepted
  Heliopsis helianthoides var. gracilis (Nutt.) Gandhi & R.D. Thomas -- not accepted -- smooth oxeye
  Heliopsis helianthoides var. helianthoides (L.) Sweet -- accepted -- smooth oxeye
  Heliopsis helianthoides var. occidentalis (T.R. Fisher) Steyerm. -- not accepted -- smooth oxeye
  Heliopsis helianthoides var. scabra (Dunal) Fernald -- accepted -- smooth oxeye, heliopsis
  Heliopsis helianthoides var. solidaginoides (L.) Fernald -- not accepted
  Heliopsis minor (Hook.) C. Mohr -- not accepted
  Heliopsis parvifolia A. Gray -- accepted -- mountain oxeye
  Heliopsis scabra Dunal -- not accepted
  Helipterum roseum (Hook.) Benth. -- not accepted
  Helminthotheca Zinn -- accepted
  Helminthotheca echioides (L.) Holub -- accepted -- bristly oxtongue
  Hemiachyris glutinosa S. Schauer -- not accepted
  Hemiachyris texana DC. -- not accepted
  Hemizonella (A. Gray) A. Gray -- accepted
  Hemizonella minima (A. Gray) A. Gray -- accepted -- opposite-leaved tarweed
  Hemizonia DC. -- accepted -- tarweed
  Hemizonia arida D.D. Keck -- not accepted -- Redrock tarweed
  Hemizonia australis (D.D. Keck) D.D. Keck -- not accepted
  Hemizonia calyculata (Babc. & H.M. Hall) D.D. Keck -- not accepted
  Hemizonia clementina Brandegee -- not accepted -- Catalina tarweed
  Hemizonia clevelandii Greene -- not accepted
  Hemizonia congesta DC. -- accepted -- hayfield tarweed
  Hemizonia congesta ssp. calyculata Babc. & H.M. Hall -- accepted -- hayfield tarweed
  Hemizonia congesta ssp. clevelandii (Greene) Babc. & H.M. Hall -- accepted -- hayfield tarweed
  Hemizonia congesta ssp. congesta DC. -- accepted -- hayfield tarweed
  Hemizonia congesta ssp. leucocephala (Tanowitz) Keil -- not accepted -- hayfield tarweed
  Hemizonia congesta ssp. lutescens (Greene) Babc. & H.M. Hall -- accepted -- hayfield tarweed
  Hemizonia congesta ssp. luzulifolia (DC.) Babc. & H.M. Hall -- accepted -- hayfield tarweed
  Hemizonia congesta ssp. tracyi Babc. & H.M. Hall -- accepted -- hayfield tarweed
  Hemizonia congesta ssp. vernalis (D.D. Keck) Tanowitz -- not accepted -- hayfield tarweed
  Hemizonia conjugens D.D. Keck -- not accepted -- Otay tarplant, Otay tarweed
  Hemizonia corymbosa (DC.) Torr. & A. Gray -- not accepted -- coastal tarweed
  Hemizonia corymbosa ssp. corymbosa (DC.) Torr. & A. Gray -- not accepted -- coastal tarweed
  Hemizonia corymbosa ssp. macrocephala (Nutt.) D.D. Keck -- not accepted -- coastal tarweed
  Hemizonia douglasii A. Gray -- not accepted
  Hemizonia fasciculata (DC.) Torr. & A. Gray -- not accepted -- clustered tarweed
  Hemizonia fitchii A. Gray -- not accepted -- Fitch's tarweed
  Hemizonia floribunda A. Gray -- not accepted -- Tecate tarweed
  Hemizonia fremontii (A. Gray) A. Gray -- not accepted
  Hemizonia halliana D.D. Keck -- not accepted -- Hall's tarweed
  Hemizonia hispida Greene -- not accepted
  Hemizonia increscens (H.M. Hall ex D.D. Keck) Tanowitz -- not accepted -- grassland tarweed
  Hemizonia increscens ssp. foliosa (Hoover) Tanowitz -- not accepted -- grassland tarweed
  Hemizonia increscens ssp. increscens (H.M. Hall ex D.D. Keck) Tanowitz -- not accepted -- grassland tarweed
  Hemizonia increscens ssp. villosa Tanowitz -- not accepted -- grassland tarweed
  Hemizonia kelloggii Greene -- not accepted -- Kellogg's tarweed
  Hemizonia laevis (D.D. Keck) D.D. Keck -- not accepted
  Hemizonia leucocephala Tanowitz -- not accepted
  Hemizonia lobbii Greene -- not accepted -- threeray tarweed
  Hemizonia lutescens (Greene) D.D. Keck -- not accepted
  Hemizonia luzulifolia DC. -- not accepted
  Hemizonia luzulifolia ssp. luzulifolia DC. -- not accepted -- hayfield tarweed
  Hemizonia luzulifolia ssp. rudis (Benth.) D.D. Keck -- not accepted
  Hemizonia luzulifolia ssp. tracyi Babc. & H.M. Hall -- not accepted
  Hemizonia luzulifolia var. lutescens Greene -- not accepted
  Hemizonia minthornii Jeps. -- not accepted -- Santa Susana tarweed
  Hemizonia mohavensis D.D. Keck -- not accepted -- Mojave tarweed
  Hemizonia mollis (A. Gray) A. Gray -- not accepted
  Hemizonia multicaulis Hook. & Arn. -- not accepted
  Hemizonia multicaulis ssp. vernalis D.D. Keck -- not accepted
  Hemizonia multicaulis var. multicaulis Hook. & Arn. -- not accepted
  Hemizonia multiglandulosa var. sparsa A. Gray -- not accepted
  Hemizonia oppositifolia Greene -- not accepted
  Hemizonia pallida D.D. Keck -- not accepted -- Kern tarweed
  Hemizonia paniculata A. Gray -- not accepted -- San Diego tarweed
  Hemizonia paniculata ssp. increscens H.M. Hall ex D.D. Keck -- not accepted
  Hemizonia paniculata var. paniculata A. Gray -- not accepted
  Hemizonia parryi Greene -- not accepted -- pappose tarweed
  Hemizonia parryi ssp. australis D.D. Keck -- not accepted -- pappose tarweed
  Hemizonia parryi ssp. congdonii (B.L. Rob. & Greenm.) D.D. Keck -- not accepted -- Congdon's tarweed
  Hemizonia parryi ssp. parryi Greene -- not accepted -- pappose tarweed
  Hemizonia parryi ssp. rudis (Greene) D.D. Keck -- not accepted -- pappose tarweed
  Hemizonia pauciflora (A. Gray) A. Gray -- not accepted
  Hemizonia pentactis (D.D. Keck) D.D. Keck -- not accepted -- Salinas River tarweed
  Hemizonia pungens (Hook. & Arn.) Torr. & A. Gray -- not accepted -- spikeweed, common tarweed, common spikeweed
  Hemizonia pungens ssp. laevis D.D. Keck -- not accepted -- common tarweed, spikeweed
  Hemizonia pungens ssp. maritima (Greene) D.D. Keck -- not accepted -- spikeweed, common tarweed
  Hemizonia pungens ssp. pungens (Hook. & Arn.) Torr. & A. Gray -- not accepted -- spikeweed, common tarweed
  Hemizonia pungens ssp. septentrionalis D.D. Keck -- not accepted -- spikeweed, common tarweed
  Hemizonia pungens var. septentrionalis (D.D. Keck) Cronquist -- not accepted
  Hemizonia ramosissima Benth. -- not accepted
  Hemizonia scabrella E. Drew -- not accepted
  Hemizonia spicata Greene -- not accepted
  Hemizonia tenella (Nutt.) A. Gray -- not accepted
  Hemizonia tracyi (Babc. & H.M. Hall) D.D. Keck -- not accepted
  Hemizonia truncata (DC.) A. Gray -- not accepted
  Herrickia Woot. & Standl. -- accepted -- herrickia
  Herrickia glauca (Nutt.) Brouillet -- accepted -- Gray's aster
  Herrickia glauca var. glauca (Nutt.) Brouillet -- accepted -- Gray's aster
  Herrickia glauca var. pulchra (S.F. Blake) Brouillet -- accepted -- beautiful aster
  Herrickia horrida Woot. & Standl. -- accepted -- horrid herrickia
  Herrickia kingii (D.C. Eaton) Brouillet, Urbatsch & R.P. Roberts -- accepted -- King's aster
  Herrickia kingii var. barnebyana (S.L. Welsh & Goodrich) Brouillet, Urbatsch & R.P. Roberts -- accepted -- Barneby's aster
  Herrickia kingii var. kingii (D.C. Eaton) Brouillet, Urbatsch & R.P. Roberts -- accepted -- King's aster
  Herrickia wasatchensis (M.E. Jones) Brouillet -- accepted -- Wasatch aster
  Hertia Neck. -- accepted
  Hertia cheirifolia Kuntze -- accepted
  Hesperevax (A. Gray) A. Gray -- accepted -- dwarf-cudweed
  Hesperevax acaulis (Kellogg) Greene -- accepted -- stemless dwarf-cudweed
  Hesperevax acaulis var. acaulis (Kellogg) Greene -- accepted -- stemless dwarf-cudweed
  Hesperevax acaulis var. ambusticola Morefield -- accepted -- stemless dwarf-cudweed
  Hesperevax acaulis var. robustior Morefield -- accepted -- stemless dwarf-cudweed
  Hesperevax caulescens (Benth.) A. Gray -- accepted -- dwarf dwarf-cudweed
  Hesperevax sparsiflora (A. Gray) Greene -- accepted -- erect dwarf-cudweed
  Hesperevax sparsiflora var. brevifolia (A. Gray) Morefield -- accepted -- shortleaf dwarf-cudweed
  Hesperevax sparsiflora var. sparsiflora (A. Gray) Greene -- accepted -- erect dwarf-cudweed
  Hesperodoria Greene -- accepted -- glowweed, hesperodoria
  Hesperodoria hallii (A. Gray) Greene -- not accepted
  Hesperodoria salicina (S.F. Blake) G.L. Nesom -- not accepted -- willow glowweed
  Hesperodoria scopulorum (M.E. Jones) Greene -- not accepted -- Grand Canyon glowweed, Grand Canyon glow-weed
  Hesperomannia A. Gray -- accepted -- island-aster
  Hesperomannia arborescens A. Gray -- accepted -- Lanai island-aster
  Hesperomannia arborescens var. arborescens A. Gray -- not accepted
  Hesperomannia arborescens var. bushiana (O. Deg.) Carlq. -- not accepted
  Hesperomannia arborescens var. swezeyi (O. Deg.) Carlq. -- not accepted
  Hesperomannia arbuscula Hillebr. -- not accepted -- Maui island-aster
  Hesperomannia arbuscula ssp. oahuensis (Hillebr.) Carlq. -- not accepted
  Hesperomannia arbuscula var. arbuscula Hillebr. -- not accepted
  Hesperomannia arbuscula var. pearsallii H. St. John -- not accepted
  Hesperomannia lydgatei C.N. Forbes -- accepted -- Kauai island-aster
  Hesperomannia mauiensis H. St. John -- not accepted
  Heteranthemis Schott -- accepted -- oxeye
  Heteranthemis viscidehirta Schott -- accepted -- sticky oxeye
  Heteropappus Less. -- accepted
  Heteropappus altaicus (Willd.) Novopokr. -- accepted
  Heterosperma Cav. -- accepted -- heterosperma
  Heterosperma pinnatum Cav. -- accepted -- wingpetal
  Heterotheca Cass. -- accepted -- false goldenaster, telegraph plant, telegraphplant
  Heterotheca adenolepis (Fernald) H.E. Ahles -- not accepted
  Heterotheca aspera (Shuttlw. ex Small) Shinners -- not accepted
  Heterotheca barbata (Rydb.) Semple -- accepted -- Spokane false goldenaster
  Heterotheca bolanderi (A. Gray) V.L. Harms -- not accepted
  Heterotheca breweri (A. Gray) Shinners -- not accepted
  Heterotheca camphorata (Eastw.) Semple -- not accepted
  Heterotheca camporum (Greene) Shinners -- accepted -- lemonyellow false goldenaster
  Heterotheca camporum var. camporum (Greene) Shinners -- accepted -- lemonyellow false goldenaster
  Heterotheca camporum var. glandulissimum Semple -- accepted -- lemonyellow false goldenaster
  Heterotheca canescens (DC.) Shinners -- accepted -- hoary false goldenaster, gray goldaster, hoary falsegoldenaster
  Heterotheca correllii (Fernald) H.E. Ahles -- not accepted
  Heterotheca cruiseana (Dress) V.L. Harms -- not accepted
  Heterotheca depressa (Rydb.) Dorn -- not accepted
  Heterotheca echioides (Benth.) Shinners -- not accepted
  Heterotheca falcata (Pursh) V.L. Harms -- not accepted
  Heterotheca fastigiata (Greene) V.L. Harms -- not accepted
  Heterotheca flexuosa (Nash) V.L. Harms -- not accepted
  Heterotheca floribunda Benth. -- not accepted
  Heterotheca floridana (Small) R.W. Long -- not accepted
  Heterotheca foliosa (Nutt.) Shinners -- not accepted
  Heterotheca fulcrata (Greene) Shinners -- accepted -- rockyscree false goldenaster, rockyscree falsegoldenaster, mountain camphorweed
  Heterotheca fulcrata var. amplifolia (Rydb.) Semple -- accepted -- rockyscree false goldenaster
  Heterotheca fulcrata var. arizonica Semple -- accepted -- Arizona false goldenaster, Arizona falsegoldenaster
  Heterotheca fulcrata var. fulcrata (Greene) Shinners -- accepted -- rockyscree false goldenaster, rocky false goldenaster, rockyscree falsegoldenaster
  Heterotheca fulcrata var. senilis (Woot. & Standl.) Semple -- accepted -- rockyscree false goldenaster, rockyscree falsegoldenaster
  Heterotheca gossypina (Michx.) Shinners -- not accepted
  Heterotheca graminifolia (Michx.) Shinners -- not accepted
  Heterotheca graminifolia var. microcephala (Small) Cronq. -- not accepted
  Heterotheca graminifolia var. tenuifolia (Torr.) Gandhi & R.D. Thomas -- not accepted
  Heterotheca graminifolia var. tracyi (Small) R.W. Long -- not accepted
  Heterotheca grandiflora Nutt. -- accepted -- telegraphweed, telegraph weed
  Heterotheca horrida (Rydb.) V.L. Harms -- not accepted
  Heterotheca horrida ssp. cinerascens (S.F. Blake) Semple -- not accepted
  Heterotheca hyssopifolia (Nutt.) R.W. Long -- not accepted
  Heterotheca hyssopifolia var. gigantea (Small) V.L. Harms -- not accepted
  Heterotheca hyssopifolia var. subulata (Small) R.W. Long -- not accepted
  Heterotheca jonesii (S.F. Blake) S.L. Welsh & N.D. Atwood -- accepted -- Jones' false goldenaster
  Heterotheca lamarckii Cass. -- not accepted
  Heterotheca latifolia Buckley -- not accepted
  Heterotheca latifolia var. arkansana Wagenkn. -- not accepted
  Heterotheca latifolia var. macgregoris Wagenkn. -- not accepted
  Heterotheca latisquamea (Pollard) V.L. Harms -- not accepted
  Heterotheca marginata Semple -- accepted -- Sonora false goldenaster
  Heterotheca mariana (L.) Shinners -- not accepted
  Heterotheca mariana ssp. floridana (Small) V.L. Harms -- not accepted
  Heterotheca mariana var. macradenia (Fernald) V.L. Harms -- not accepted
  Heterotheca microcephala (Small) Shinners -- not accepted
  Heterotheca monarchensis York, Shevock & Semple -- accepted -- Sequoia false goldenaster
  Heterotheca nervosa (Willd.) Shinners -- not accepted
  Heterotheca nervosa var. microcephala (Small) Shinners ex H.E. Ahles -- not accepted
  Heterotheca oligantha (Chapm. ex Torr. & A. Gray) V.L. Harms -- not accepted
  Heterotheca oregona (Nutt.) Shinners -- accepted -- Oregon false goldenaster
  Heterotheca oregona var. compacta (D.D. Keck) Semple -- accepted -- Oregon false goldenaster
  Heterotheca oregona var. oregona (Nutt.) Shinners -- accepted -- Oregon false goldenaster
  Heterotheca oregona var. rudis (Greene) Semple -- accepted -- Oregon false goldenaster
  Heterotheca oregona var. scaberrima (A. Gray) Semple -- accepted -- Oregon false goldenaster
  Heterotheca pilosa (Nutt.) Shinners -- not accepted
  Heterotheca pinifolia (Elliot) H.E. Ahles -- not accepted
  Heterotheca psammophila Wagenkn. -- not accepted
  Heterotheca pumila (Greene) Semple -- accepted -- alpine false goldenaster
  Heterotheca ruthii (Small) V.L. Harms -- not accepted
  Heterotheca rutteri (Rothr.) Shinners -- accepted -- Rutter's false goldenaster
  Heterotheca scabra (Pursh) DC. -- not accepted
  Heterotheca scabrella (Torr. & A. Gray) V.L. Harms -- not accepted
  Heterotheca sessiliflora (Nutt.) Shinners -- accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora ssp. bolanderi (A. Gray) Semple -- accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora ssp. echioides (Benth.) Semple -- accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora ssp. echioides var. bolanderioides Semple -- not accepted
  Heterotheca sessiliflora ssp. echioides var. camphorata (Eastw.) Semple -- not accepted
  Heterotheca sessiliflora ssp. echioides var. echioides (Benth.) Semple -- not accepted
  Heterotheca sessiliflora ssp. fastigiata (Greene) Semple -- accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora ssp. fastigiata var. fastigiata (Greene) Semple -- not accepted
  Heterotheca sessiliflora ssp. fastigiata var. sanjacintensis Semple -- not accepted
  Heterotheca sessiliflora ssp. sessiliflora (Nutt.) Shinners -- accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora var. bolanderioides Semple -- not accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora var. camphorata (Eastw.) Semple -- not accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora var. echioides (Benth.) Semple -- not accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora var. fastigiata (Greene) Semple -- not accepted -- sessileflower false goldenaster
  Heterotheca sessiliflora var. sanjacintensis Semple -- not accepted -- sessileflower false goldenaster
  Heterotheca shevockii (Semple) Semple -- accepted -- Kern Canyon false goldenaster
  Heterotheca stenophylla (A. Gray) Shinners -- accepted -- stiffleaf false goldenaster, stiffleaf falsegoldenaster
  Heterotheca stenophylla var. angustifolia (Rydb.) Semple -- accepted -- stiffleaf false goldenaster
  Heterotheca stenophylla var. stenophylla (A. Gray) Shinners -- accepted -- stiffleaf false goldenaster
  Heterotheca subaxillaris (Lam.) Britton & Rusby -- accepted -- camphorweed, golden aster
  Heterotheca subaxillaris ssp. latifolia (Buckley) Semple -- accepted
  Heterotheca subaxillaris ssp. subaxillaris (Lam.) Britton & Rusby -- accepted
  Heterotheca subaxillaris var. latifolia (Buckley) Gandhi & R.D. Thomas -- not accepted
  Heterotheca subaxillaris var. petiolaris Benke -- not accepted
  Heterotheca subaxillaris var. procumbens Wagenkn. -- not accepted
  Heterotheca subaxillaris var. psammophila (Wagenkn.) Gandhi -- not accepted
  Heterotheca subaxillaris var. subaxillaris (Lam.) Britt. & Rusby -- not accepted -- camphorweed
  Heterotheca subulata (Small) V.L. Harms -- not accepted
  Heterotheca trichophylla (Nutt.) Shinners -- not accepted
  Heterotheca villosa (Pursh) Shinners -- accepted -- hairy false goldenaster, hairy goldaster, hairy goldenaster, hairy false goldaster
  Heterotheca villosa var. angustifolia (Rydb.) Semple -- not accepted
  Heterotheca villosa var. ballardii (Rydb.) Semple -- accepted -- hairy false goldenaster
  Heterotheca villosa var. camporum (Greene) Wunderlin -- not accepted
  Heterotheca villosa var. depressa (Rydb.) Semple -- accepted -- hairy false goldenaster
  Heterotheca villosa var. foliosa (Nutt.) V.L. Harms -- accepted -- hairy false goldenaster
  Heterotheca villosa var. hispida (Hook.) V.L. Harms -- not accepted -- bristly hairy goldaster
  Heterotheca villosa var. horrida (Hook.) Semple -- not accepted
  Heterotheca villosa var. minor (Hook.) Semple -- accepted -- hairy false goldenaster
  Heterotheca villosa var. nana (A. Gray) Semple -- accepted -- hairy false goldenaster
  Heterotheca villosa var. pedunculata (Greene) V.L. Harms ex Semple -- accepted -- hairy false goldenaster
  Heterotheca villosa var. scabra (Eastw.) Semple -- accepted -- hairy false goldenaster
  Heterotheca villosa var. shevockii Semple -- not accepted
  Heterotheca villosa var. sierrablancensis Semple -- accepted -- hairy false goldenaster
  Heterotheca villosa var. villosa (Pursh) Shinners -- accepted -- hairy false goldenaster, hairy false golden-aster
  Heterotheca viscida (A. Gray) V.L. Harms -- accepted -- cliff false goldenaster, cliff falsegoldenaster
  Heterotheca wisconsinensis (Shinners) Shinners -- not accepted
  Heterotheca zionensis Semple -- accepted -- Zion false goldenaster
  Hieracium L. -- accepted -- hawkweed
  Hieracium abscissum Less. -- accepted -- Rusby's hawkweed
  Hieracium acranthophorum Om. -- not accepted -- Tunugdliarfik hawkweed
  Hieracium acranthophorum var. acranthophorum Om. -- not accepted -- Tunugdliarfik hawkweed
  Hieracium acranthophorum var. isortoquense Böcher -- not accepted -- Tunugdliarfik hawkweed
  Hieracium acuminatum Jord. -- not accepted
  Hieracium albertinum Farr -- not accepted
  Hieracium albiflorum Hook. -- accepted -- white hawkweed, whiteflower hawkweed
  Hieracium alpinum L. -- accepted -- alpine hawkweed
  Hieracium amitsokense Dahlst. -- not accepted -- royal hawkweed
  Hieracium angmagssalikense Om. -- not accepted -- blackstyle hawkweed
  Hieracium argutum Nutt. -- accepted -- southern hawkweed
  Hieracium argutum var. argutum Nutt. -- not accepted -- southern hawkweed
  Hieracium argutum var. parishii (A. Gray) Jeps. -- not accepted
  Hieracium argyraeum Small -- not accepted
  Hieracium atratum Fr. -- accepted -- polar hawkweed
  Hieracium aurantiacum L. -- accepted -- orange hawkweed
  Hieracium auricula auct. non L. -- not accepted
  Hieracium bolanderi A. Gray -- accepted -- Bolander's hawkweed
  Hieracium brevipilum Greene -- accepted -- Mogollon hawkweed
  Hieracium caespitosum Dumort. -- accepted -- meadow hawkweed, yellow hawkweed
  Hieracium canadense Michx. -- accepted -- Canadian hawkweed, yellow hawkweed
  Hieracium canadense var. canadense Michx. -- not accepted -- Canadian hawkweed
  Hieracium canadense var. fasciculatum (Pursh) Fernald -- not accepted -- Canadian hawkweed
  Hieracium canadense var. hirtirameum Fernald -- not accepted
  Hieracium canadense var. kalmii (L.) Scoggan -- not accepted
  Hieracium canadense var. subintegrum Lepage -- not accepted -- Canadian hawkweed
  Hieracium carneum Greene -- accepted -- Huachuca hawkweed
  Hieracium chapacanum Zahn -- not accepted
  Hieracium columbianum Rydb. -- not accepted
  Hieracium columbianum auct. non Rydb. -- not accepted
  Hieracium crepidispermum Fr. -- accepted -- Lemmon's hawkweed
  Hieracium cusickii Gandog. -- not accepted
  Hieracium cynoglossoides Arv.-Touv. -- not accepted -- houndstongue hawkweed
  Hieracium cynoglossoides var. nudicaule A. Gray -- not accepted
  Hieracium devoldii Om. -- not accepted -- Devold's hawkweed
  Hieracium eugenii Om. -- not accepted -- neria hawkweed
  Hieracium fendleri Sch. Bip. -- accepted -- yellow hawkweed, yellow hawksbeard
  Hieracium fendleri var. discolor A. Gray -- not accepted -- yellow hawkweed
  Hieracium fendleri var. fendleri Sch. Bip. -- accepted -- yellow hawkweed, Fendler's hawkweed
  Hieracium fendleri var. mogollense A. Gray -- not accepted -- Mogollon hawkweed
  Hieracium flagellare Willd. -- accepted -- hawkweed
  Hieracium flagellare ssp. amauracron Missbach & Zahn -- not accepted
  Hieracium flagellare ssp. cernuiforme Naegeli & Peter -- not accepted
  Hieracium flagellare ssp. glatzense Naegeli & Peter -- not accepted
  Hieracium flettii H. St. John & Warren -- not accepted
  Hieracium florentinum All. -- not accepted
  Hieracium glomeratum Froel. -- accepted -- queen-devil hawkweed
  Hieracium gracile Hook. -- not accepted -- slender hawkweed
  Hieracium gracile var. alaskanum Zahn -- not accepted -- Alaska hawkweed
  Hieracium gracile var. densifloccosum (Zahn) Cronquist -- not accepted
  Hieracium gracile var. detonsum (A. Gray) A. Gray -- not accepted -- low alpine hawkweed
  Hieracium gracile var. gracile Hook. -- not accepted -- slender hawkweed
  Hieracium gracile var. yukonense A.E. Porsild -- not accepted -- Yukon hawkweed
  Hieracium greenei A. Gray -- accepted -- Greene's hawkweed
  Hieracium greenii Porter & Britton -- not accepted -- Maryland hawkweed
  Hieracium gronovii L. -- accepted -- queendevil, Gronovis hawkweed
  Hieracium gronovii var. foliosum Michx. -- not accepted
  Hieracium helleri Gandog. -- not accepted
  Hieracium horridum Fr. -- accepted -- prickly hawkweed, shaggy hawkweed
  Hieracium ivigtutense Om. -- not accepted -- Holsteinsborg hawkweed
  Hieracium kalmii L. -- not accepted -- Kalm's hawkweed
  Hieracium kalmii var. canadense (Michx.) Reveal -- not accepted
  Hieracium kalmii var. fasciculatum (Pursh) Lepage -- not accepted
  Hieracium kalmii var. kalmii L. -- not accepted -- Kalm's hawkweed
  Hieracium kalmii var. subintegrum (Lepage) Lepage -- not accepted
  Hieracium lachenalii C.C. Gmel. -- not accepted -- common hawkweed
  Hieracium lactucella Wallr. -- accepted -- European hawkweed, hawkweed
  Hieracium laevigatum Willd. -- not accepted -- smooth hawkweed
  Hieracium lemmonii A. Gray -- not accepted -- Lemmon's hawkweed
  Hieracium lividorubens (Almquist) Elfstr. -- not accepted -- cow hawkweed
  Hieracium lividorubens var. lividorubens (Almquist) Elfstr. -- not accepted -- cow hawkweed
  Hieracium lividorubens var. subnudulum Dahlst. -- not accepted -- cow hawkweed
  Hieracium longiberbe Howell -- accepted -- longbeard hawkweed
  Hieracium longipilum Torr. -- accepted -- hairy hawkweed, longbeard hawkweed
  Hieracium maculatum Sm. -- accepted -- spotted hawkweed
  Hieracium marianum Willd. -- accepted -- Maryland hawkweed
  Hieracium megacephalon Nash -- not accepted -- coastalplain hawkweed
  Hieracium megacephalum Nash -- accepted -- coastal plain hawkweed
  Hieracium murorum L. -- accepted -- wall hawkweed
  Hieracium musartutense Om. -- not accepted -- Musartut hawkweed
  Hieracium nepiocratum Om. -- not accepted -- Lindenows Fjord hawkweed
  Hieracium nudicaule (A. Gray) A. Heller -- accepted -- Scouler's woollyweed
  Hieracium paniculatum L. -- accepted -- Allegheny hawkweed
  Hieracium parryi Zahn -- accepted
  Hieracium pennsylvanicum Fr. -- not accepted
  Hieracium pilosella L. -- accepted -- mouseear hawkweed
  Hieracium pilosella var. niveum Müll. Arg. -- not accepted -- mouseear hawkweed
  Hieracium pilosella var. pilosella L. -- not accepted -- mouseear hawkweed
  Hieracium piloselloides Vill. -- accepted -- tall hawkweed, kingdevil
  Hieracium praealtum Vill. ex Gochnat -- not accepted -- kingdevil
  Hieracium praealtum var. decipiens W.D.J. Koch -- not accepted -- kingdevil
  Hieracium praealtum var. praealtum Vill. ex Gochnat -- not accepted -- kingdevil
  Hieracium pratense Tausch -- not accepted -- yellow kingdevil, field hawkweed, meadow hawkweed, yellow hawkweed
  Hieracium prenanthoides Vill. -- accepted
  Hieracium pringlei A. Gray -- accepted -- Pringle's hawkweed
  Hieracium rigorosum (Laest.) Almquist -- not accepted -- rockyscree hawkweed
  Hieracium rigorosum var. nanusekense Om. -- not accepted -- rockyscree hawkweed
  Hieracium rigorosum var. rigorosum (Laest.) Almquist -- not accepted -- rockyscree hawkweed
  Hieracium rigorosum var. sermilikense Om. -- not accepted -- rockyscree hawkweed
  Hieracium rigorosum var. unanakense Om. -- not accepted -- rockyscree hawkweed
  Hieracium robinsonii (Zahn) Fernald -- accepted -- Robinson's hawkweed, épervičre de Robinson
  Hieracium rusbyi Greene -- not accepted -- Rusby's hawkweed
  Hieracium sabaudum L. -- accepted -- New England hawkweed
  Hieracium scabriusculum Schwein. -- not accepted
  Hieracium scabriusculum var. columbianum (Rydb.) Lepage -- not accepted
  Hieracium scabriusculum var. columbianum auct. non (Rydb.) Lepage -- not accepted
  Hieracium scabriusculum var. perhirsutum Lepage -- not accepted
  Hieracium scabriusculum var. saximontanum Lepage -- not accepted
  Hieracium scabriusculum var. scabrum (Schwein.) Lepage -- not accepted
  Hieracium scabrum Michx. -- accepted -- rough hawkweed
  Hieracium scabrum var. intonsum Fernald & H. St. John -- not accepted -- rough hawkweed
  Hieracium scabrum var. leucocaule Fernald & H. St. John -- not accepted -- rough hawkweed
  Hieracium scabrum var. scabrum Michx. -- not accepted -- rough hawkweed
  Hieracium scabrum var. tonsum Fernald & H. St. John -- not accepted -- rough hawkweed
  Hieracium scholanderi Om. -- not accepted -- Kap Farvel hawkweed
  Hieracium schultzii Fr. -- accepted -- roughstem hawkweed
  Hieracium scouleri Hook. -- accepted -- Scouler's woollyweed, houndstongue hawkweed, woolyweed
  Hieracium scouleri var. albertinum (Farr) G.W. Douglas & G.A. Allen -- not accepted
  Hieracium scouleri var. griseum (Rydb.) A. Nelson -- not accepted
  Hieracium scouleri var. nudicaule (A. Gray) Cronquist -- not accepted -- Scouler's woollyweed, woollyweed
  Hieracium scouleri var. scouleri Hook. -- not accepted -- Scouler's woollyweed
  Hieracium scribneri Small -- accepted -- Scribner's hawkweed
  Hieracium siskiyouense M. Peck -- not accepted
  Hieracium stiptocaule Om. -- not accepted -- Igaliko Fjord hawkweed
  Hieracium sylowii Om. -- not accepted -- brownstyle hawkweed
  Hieracium sylowii var. norwagorum Om. -- not accepted -- brownstyle hawkweed
  Hieracium sylowii var. sylowii Om. -- not accepted -- Sylow's hawkweed
  Hieracium traillii Greene -- accepted -- Maryland hawkweed
  Hieracium tridentatum Fr. -- accepted -- threetooth hawkweed
  Hieracium triste Willd. ex Spreng. -- accepted -- woolly hawkweed, slender hawkweed, low alpine hawkweed
  Hieracium triste ssp. gracile (Hook.) Calder & Roy L. Taylor -- not accepted
  Hieracium triste var. fulvum Hultén -- not accepted -- woolly hawkweed
  Hieracium triste var. gracile (Hook.) A. Gray -- not accepted
  Hieracium triste var. triste Willd. ex Spreng. -- not accepted -- woolly hawkweed
  Hieracium triste var. tritiforme Zahn -- not accepted
  Hieracium umbellatum L. -- accepted -- narrowleaf hawkweed, Canadian hawkweed, smooth hawkweed, Kalm's hawkweed, narrow-leaf hawkweed
  Hieracium umbellatum var. canadense (Michx.) Breitung -- not accepted
  Hieracium umbellatum var. scabriusculum Farw. -- not accepted
  Hieracium ungavense Lepage -- not accepted
  Hieracium vagum Jord. -- not accepted
  Hieracium venosum L. -- accepted -- rattlesnakeweed
  Hieracium venosum var. nudicaule (Michx.) Farw. -- not accepted -- rattlesnakeweed
  Hieracium venosum var. venosum L. -- not accepted -- rattlesnakeweed
  Hieracium vulgatum Fr. -- accepted -- common hawkweed
  Hieracium wrightii (A. Gray) B.L. Rob. & Greenm. -- not accepted -- roughstem hawkweed
  Hieracium X alleghaniense Britton (pro sp.) -- accepted -- Allegheny hawkweed
  Hieracium X atramentarium (Naegeli & Peter) Zahn ex Engl. (pro sp.) -- accepted -- hawkweed
  Hieracium X brachiatum Bethel. ex DC. -- accepted
  Hieracium X dorei Lepage -- not accepted
  Hieracium X duplex Peter -- not accepted
  Hieracium X dutillyanum Lepage -- not accepted -- hawkweed
  Hieracium X fassettii Lepage -- accepted -- Fassett's hawkweed
  Hieracium X fernaldii Lepage -- not accepted -- Fernald's hawkweed
  Hieracium X flagellare Willd. (pro sp.) -- not accepted -- hawkweed
  Hieracium X floribundum Wimm. & Grab. (pro sp.) -- accepted -- hawkweed
  Hieracium X fuscatrum Naegeli & Peter (pro sp.) -- accepted -- hawkweed
  Hieracium X grohii Lepage -- accepted -- Groh's hawkweed
  Hieracium X macrostolonum G. Schneid. -- not accepted
  Hieracium X marianum Willd. (pro sp.) -- not accepted -- hawkweed
  Hieracium X scribneri Small (pro sp.) -- not accepted -- Scribner's hawkweed
  Hofmeisteria laphamioides Rose -- not accepted
  Hofmeisteria pluriseta A. Gray -- not accepted
  Holocarpha Greene -- accepted -- tarweed
  Holocarpha heermannii (Greene) D.D. Keck -- accepted -- Heermann's tarweed
  Holocarpha macradenia (DC.) Greene -- accepted -- Santa Cruz tarplant
  Holocarpha obconica (J.C. Clausen & D.D. Keck) D.D. Keck -- accepted -- San Joaquin tarweed
  Holocarpha obconica ssp. autumnalis D.D. Keck -- not accepted -- San Joaquin tarweed
  Holocarpha obconica ssp. obconica (J.C. Clausen & D.D. Keck) D.D. Keck -- not accepted -- San Joaquin tarweed
  Holocarpha virgata (A. Gray) D.D. Keck -- accepted -- yellowflower tarweed
  Holocarpha virgata ssp. elongata D.D. Keck -- accepted -- wand tarbush
  Holocarpha virgata ssp. virgata (A. Gray) D.D. Keck -- accepted -- yellowflower tarweed
  Holozonia Greene -- accepted -- holozonia
  Holozonia filipes (Hook. & Arn.) Greene -- accepted -- whitecrown
  Hulsea Torr. & A. Gray -- accepted -- alpinegold, hulsea
  Hulsea algida A. Gray -- accepted -- Pacific hulsea, alpine hulsea
  Hulsea brevifolia A. Gray -- accepted -- shortleaf alpinegold
  Hulsea caespitosa A. Nelson & Kennedy -- not accepted
  Hulsea californica Torr. & A. Gray -- accepted -- San Diego alpinegold
  Hulsea californica ssp. inyoensis D.D. Keck -- not accepted
  Hulsea callicarpha (H.M. Hall) S. Watson ex Rydb. -- not accepted
  Hulsea carnosa Rydb. -- not accepted
  Hulsea heterochroma A. Gray -- accepted -- redray alpinegold, redray hulsea
  Hulsea inyoensis (D.D. Keck) Munz -- not accepted
  Hulsea larsenii (A. Gray) Rydb. -- not accepted
  Hulsea mexicana Rydb. -- accepted -- Mexican alpinegold
  Hulsea nana A. Gray -- accepted -- dwarf alpinegold
  Hulsea nana var. larsenii A. Gray -- not accepted
  Hulsea nevadensis Gandog. -- not accepted
  Hulsea parryi A. Gray -- not accepted
  Hulsea vestita A. Gray -- accepted -- pumice alpinegold, pumice hulsea
  Hulsea vestita ssp. callicarpha (H.M. Hall) Wilken -- accepted -- pumice alpinegold
  Hulsea vestita ssp. gabrielensis Wilken -- accepted -- pumice alpinegold
  Hulsea vestita ssp. inyoensis (D.D. Keck) Wilken -- accepted -- pumice alpinegold, Inyo hulsea
  Hulsea vestita ssp. parryi (A. Gray) Wilken -- accepted -- Parry's alpinegold
  Hulsea vestita ssp. pygmaea (A. Gray) Wilken -- accepted -- pygmy alpinegold
  Hulsea vestita ssp. vestita A. Gray -- accepted -- pumice alpinegold, pumice hulsea
  Hulsea vestita var. callicarpha H.M. Hall -- not accepted
  Hulsea vestita var. pygmaea A. Gray -- not accepted
  Hulsea volcanica Gandog. -- not accepted
  Hulteniella Tzvelev -- accepted
  Hulteniella integrifolia (Richardson) Tzvelev -- accepted -- entireleaf daisy
  Hymenatherum neomexicanum A. Gray -- not accepted
  Hymenatherum pentachaetum DC. -- not accepted
  Hymenatherum tagetoides (Torr. & A. Gray) A. Gray -- not accepted
  Hymenoclea Torr. & A. Gray ex A. Gray -- accepted -- burrobrush
  Hymenoclea fasciculata A. Nelson -- not accepted
  Hymenoclea monogyra Torr. & A. Gray -- not accepted -- singlewhorl burrobrush, cheeseweed burrobrush, singlewhorl burrobush
  Hymenoclea pentalepis Rydb. -- not accepted
  Hymenoclea salsola Torr. & A. Gray -- not accepted -- white burrobrush, burrobrush
  Hymenoclea salsola var. fasciculata (A. Nelson) K.M. Peterson & Payne -- not accepted -- burrobrush, white burrobush
  Hymenoclea salsola var. patula (A. Nelson) K.M. Peterson & Payne -- not accepted
  Hymenoclea salsola var. pentalepis (Rydb.) L.D. Benson -- not accepted -- burrobrush, white burrobrush
  Hymenoclea salsola var. salsola Torr. & A. Gray -- not accepted -- burrobrush, white burrobrush
  Hymenoclea sandersonii (S.L. Welsh) N.H. Holmgren -- accepted -- Sanderson's burrobrush
  Hymenopappus L'Hér. -- accepted -- hymenopappus
  Hymenopappus arenosus A. Heller -- not accepted
  Hymenopappus artemisiifolius DC. -- accepted -- oldplainsman, woolly-white
  Hymenopappus artemisiifolius var. artemisiifolius DC. -- accepted -- oldplainsman, woolly-white
  Hymenopappus artemisiifolius var. riograndensis B.L. Turner -- accepted -- oldplainsman, woolly-white
  Hymenopappus biennis B.L. Turner -- accepted -- biennial woollywhite
  Hymenopappus carolinensis (Lam.) Porter -- not accepted
  Hymenopappus carrizoanus B.L. Turner -- accepted -- Carrizo Sands woollywhite
  Hymenopappus cinereus Rydb. -- not accepted
  Hymenopappus corymbosus Torr. & A. Gray -- not accepted
  Hymenopappus eriopodus A. Nelson -- not accepted
  Hymenopappus filifolius Hook. -- accepted -- fineleaf hymenopappus, cutleaf, fine-leaf woollywhite
  Hymenopappus filifolius var. alpestris (Maguire) Shinners -- not accepted
  Hymenopappus filifolius var. cinereus (Rydb.) I.M. Johnst. -- accepted -- fineleaf hymenopappus, fine-leaf woollywhite
  Hymenopappus filifolius var. eriopodus (A. Nelson) B.L. Turner -- accepted -- fineleaf hymenopappus
  Hymenopappus filifolius var. filifolius Hook. -- accepted -- fineleaf hymenopappus
  Hymenopappus filifolius var. idahoensis B.L. Turner -- accepted -- Idaho hymenopappus, fineleaf hymenopappus
  Hymenopappus filifolius var. lugens (Greene) Jeps. -- accepted -- fineleaf hymenopappus, Idaho hymenopappus, yellow cutleaf
  Hymenopappus filifolius var. luteus (Nutt.) B.L. Turner -- accepted -- fineleaf hymenopappus
  Hymenopappus filifolius var. megacephalus B.L. Turner -- accepted -- fineleaf hymenopappus
  Hymenopappus filifolius var. nanus (Rydb.) B.L. Turner -- accepted -- fineleaf hymenopappus
  Hymenopappus filifolius var. nudipes (Maguire) B.L. Turner -- accepted -- alpine hymenopappus, alpine woolywhite
  Hymenopappus filifolius var. parvulus (Greene) B.L. Turner -- accepted -- fineleaf hymenopappus
  Hymenopappus filifolius var. pauciflorus (I.M. Johnst.) B.L. Turner -- accepted -- fineleaf hymenopappus
  Hymenopappus filifolius var. polycephalus (Osterh.) B.L. Turner -- accepted -- manyhead hymenopappus, fine-leaf woollywhite
  Hymenopappus filifolius var. tomentosus (Rydb.) B.L. Turner -- accepted -- finehair hymenopappus
  Hymenopappus flavescens A. Gray -- accepted -- collegeflower, yellow woollywhite, yellow woolywhite
  Hymenopappus flavescens var. canotomentosus A. Gray -- accepted -- collegeflower, college flower
  Hymenopappus flavescens var. flavescens A. Gray -- accepted -- collegeflower
  Hymenopappus flavomarginatus I.M. Johnst. -- accepted
  Hymenopappus gloriosus A. Heller -- not accepted
  Hymenopappus lugens Greene -- not accepted
  Hymenopappus luteus Nutt. -- not accepted
  Hymenopappus mexicanus A. Gray -- accepted -- Mexican woollywhite
  Hymenopappus newberryi (A. Gray) I.M. Johnst. -- accepted -- Newberry's hymenopappus, Newberry's woollywhite
  Hymenopappus pauciflorus I.M. Johnst. -- not accepted
  Hymenopappus polycephalus Osterh. -- not accepted
  Hymenopappus radiatus Rose -- accepted -- ray hymenopappus, ray woollywhite
  Hymenopappus robustus Greene -- not accepted
  Hymenopappus scabiosaeus L'Hér. -- accepted -- Carolina woollywhite, white woolywhite, flattop woollywhite
  Hymenopappus scabiosaeus var. artemisiifolius (DC.) Gandhi & R.D. Thomas -- not accepted
  Hymenopappus scabiosaeus var. corymbosus (Torr. & A. Gray) B.L. Turner -- accepted -- Carolina woollywhite
  Hymenopappus scabiosaeus var. riograndensis (B.L. Turner) Gandhi -- not accepted
  Hymenopappus scabiosaeus var. scabiosaeus L'Hér. -- accepted -- Carolina woollywhite
  Hymenopappus tenuifolius Pursh -- accepted -- Chalk Hill hymenopappus, Chalkhill woolywhite, chalkhill woollywhite
  Hymenothrix A. Gray -- accepted -- thimblehead, hymenothrix
  Hymenothrix loomisii S.F. Blake -- accepted -- Loomis' thimblehead
  Hymenothrix wislizeni A. Gray -- accepted -- Trans-Pecos thimblehead
  Hymenothrix wrightii A. Gray -- accepted -- Wright's thimblehead
  Hymenoxys Cass. -- accepted -- rubberweed, hymenoxys
  Hymenoxys acaulis (Pursh) K.F. Parker -- not accepted -- stemless hymenoxys
  Hymenoxys acaulis var. arizonica (Greene) K.F. Parker -- not accepted -- Arizona hymenoxys
  Hymenoxys acaulis var. caespitosa (A. Nelson) K.F. Parker -- not accepted -- caespitose hymenoxys
  Hymenoxys acaulis var. epunctata (A. Nelson) Cronquist -- not accepted
  Hymenoxys acaulis var. glabra (A. Gray) K.F. Parker -- not accepted
  Hymenoxys acaulis var. ivesiana (Greene) K.F. Parker -- not accepted
  Hymenoxys acaulis var. lanata (Greene) Cronquist -- not accepted
  Hymenoxys acaulis var. nana S.L. Welsh -- not accepted
  Hymenoxys ambigens (S.F. Blake) Bierner -- accepted -- Pinaleno Mountain rubberweed, Pinaleno hymenoxys, Pinaleno Mountain false rubber
  Hymenoxys ambigens var. ambigens (S.F. Blake) Bierner -- accepted -- Pinaleno Mountain rubberweed
  Hymenoxys ambigens var. floribunda (A. Gray) W.L. Wagner -- accepted -- Apache Pass rubberweed
  Hymenoxys ambigens var. neomexicana W.L. Wagner -- accepted
  Hymenoxys anthemoides (Juss.) Cass. -- accepted -- South American rubberweed
  Hymenoxys argentea (A. Gray) K.F. Parker -- not accepted
  Hymenoxys argentea var. ivesiana (Greene) Cronquist -- not accepted
  Hymenoxys bigelovii (A. Gray) K.F. Parker -- accepted -- Bigelow's rubberweed
  Hymenoxys brachyactis Woot. & Standl. -- accepted -- East View rubberweed
  Hymenoxys brandegeei Porter ex A. Gray -- accepted -- Brandegee's four-nerve daisy, Brandegee's hymenoxys
  Hymenoxys cooperi (A. Gray) Cockerell -- accepted -- Cooper's rubberweed, Cooper's hymenoxys
  Hymenoxys cooperi var. canescens (D.C. Eaton) K.F. Parker -- not accepted -- Cooper's rubberweed, Cooper's frostmat, Cooper's hymenoxys
  Hymenoxys cooperi var. cooperi (A. Gray) Cockerell -- not accepted -- Cooper's rubberweed, Cooper's frostmat, Cooper's hymenoxys
  Hymenoxys depressa (Torr. & A. Gray ex A. Gray) S.L. Welsh & Reveal -- not accepted
  Hymenoxys glabra (Nutt.) Shinners -- not accepted
  Hymenoxys grandiflora (Torr. & A. Gray ex A. Gray) K.F. Parker -- accepted -- graylocks four-nerve daisy, graylocks hymenoxys
  Hymenoxys helenioides (Rydb.) Cockerell -- accepted -- Intermountain rubberweed, Intermountain bitterweed, Intermountain hymenoxys
  Hymenoxys herbacea (Greene) Cusick -- not accepted -- lakeside daisy
  Hymenoxys hoopesii (A. Gray) Bierner -- accepted -- owl's-claws, sneezeweed, orange sneezeweed, owlsclaws
  Hymenoxys ivesiana (Greene) K.F. Parker -- not accepted
  Hymenoxys jamesii Bierner -- accepted -- Jame's rubberweed
  Hymenoxys lapidicola S.L. Welsh & Neese -- not accepted -- stone rubberweed
  Hymenoxys lemmonii (Greene) Cockerell -- accepted -- Lemmon's rubberweed, Lemmon's bitterweed
  Hymenoxys linearifolia Hook. -- not accepted
  Hymenoxys microcephala (A. Gray) Bierner -- not accepted -- Apache Pass false rubbervine, Apache Pass rubberweed
  Hymenoxys odorata DC. -- accepted -- bitter rubberweed, poison rubberweed, bitterweed, western bitterweed
  Hymenoxys olivacea Cockerell -- not accepted
  Hymenoxys quinquesquamata Rydb. -- accepted -- rincon rubberweed
  Hymenoxys richardsonii (Hook.) Cockerell -- accepted -- pingue rubberweed, Colorado rubberweed, pingue, pingue hymenoxys
  Hymenoxys richardsonii var. floribunda (A. Gray) K.F. Parker -- accepted -- Colorado rubberweed
  Hymenoxys richardsonii var. richardsonii (Hook.) Cockerell -- accepted -- pingue rubberweed, Colorado rubberweed, pingue hymenoxys
  Hymenoxys richardsonii var. utahensis Cockerell -- not accepted
  Hymenoxys rusbyi (A. Gray) Cockerell -- accepted -- Rusby's rubberweed
  Hymenoxys scaposa (DC.) K.F. Parker -- not accepted -- stemmy hymenoxys
  Hymenoxys scaposa var. argyrocaulon K.F. Parker -- not accepted -- stemmy hymenoxys
  Hymenoxys scaposa var. glabra (Nutt.) K.F. Parker -- not accepted
  Hymenoxys scaposa var. linearis (Nutt.) K.F. Parker -- not accepted
  Hymenoxys scaposa var. villosa Shinners -- not accepted
  Hymenoxys subintegra Cockerell -- accepted -- Arizona rubberweed
  Hymenoxys texana (J.M. Coult. & Rose) Cockerell -- accepted -- prairiedawn, Texas bitterweed, Texas prairie dawn-flower
  Hymenoxys torreyana (Nutt.) K.F. Parker -- not accepted
  Hymenoxys turneri K.F. Parker -- not accepted -- Turner's hymenoxys
  Hymenoxys vaseyi (A. Gray) Cockerell -- accepted -- Vasey's rubberweed
  Hyoseris biflora Walter -- not accepted
  Hyoseris minima L. -- not accepted
  Hyoseris virginica L. -- not accepted
  Hypochaeris L. -- accepted -- cat's ear, catsear
  Hypochaeris brasiliensis (Less.) Benth. & Hook. ex Griseb. -- not accepted -- Brazilian catsear
  Hypochaeris brasiliensis var. brasiliensis (Less.) Griseb. -- not accepted -- Brazilian catsear
  Hypochaeris brasiliensis var. tweediei (Hook. & Arn.) Baker -- not accepted
  Hypochaeris brasiliensis var. tweedyi (Hook. & Arn.) Baker -- not accepted -- Tweedy's catsear
  Hypochaeris chillensis (Kunth) Britton -- accepted -- Tweedy's cat's ear, Brazilian cat's ear
  Hypochaeris elata auct. non (Weddell) Griseb. -- not accepted
  Hypochaeris glabra L. -- accepted -- smooth cat's ear, smooth catsear
  Hypochaeris microcephala (Sch. Bip.) Cabrera -- accepted -- smallhead cat's ear, smallhead catsear
  Hypochaeris microcephala var. albiflora (Kuntze) Cabrera -- accepted -- smallhead cat's ear, smallhead catsear
  Hypochaeris microcephala var. microcephala (Sch. Bip.) Cabrera -- accepted -- smallhead cat's ear, smallhead catsear
  Hypochaeris radicata L. -- accepted -- hairy cat's ear, common cat's-ear, false dandelion, frogbit, gosmore, spotted catsear, hairy catsear
  Hypochaeris tweediei Hook. & Arn. -- not accepted
  Hypochaeris tweedyi Hook. & Arn. -- not accepted
  Hypochoeris L. -- not accepted -- catsear
  Inula L. -- accepted -- yellowhead
  Inula alba Nutt. -- not accepted
  Inula brittanica L. -- not accepted
  Inula divaricata Nutt. -- not accepted
  Inula dysenterica L. -- not accepted
  Inula ericoides Torr. -- not accepted
  Inula gossypina Michx. -- not accepted
  Inula graveolens (L.) Desf. -- not accepted
  Inula helenium L. -- accepted -- elecampane inula
  Inula hookeri C.B. Clarke -- accepted -- Hooker's inula
  Inula mariana L. -- not accepted
  Inula salicina L. -- accepted -- willowleaf yellowhead
  Inula viscosa (L.) Aiton -- not accepted
  Ionactis Greene -- accepted -- aster, ionactis
  Ionactis alpina (Nutt.) Greene -- accepted -- lava aster, crag aster
  Ionactis caelestis Leary & G.L. Nesom -- accepted -- Spring Mountains aster, Red Rock Canyon aster
  Ionactis elegans (Soreng & Spellenb.) G.L. Nesom -- accepted -- Sierra Blanca least-daisy, Sierra Blanca leastdaisy
  Ionactis linariifolia (L.) Greene -- accepted -- flaxleaf whitetop aster
  Ionactis linariifolius (L.) Greene -- not accepted -- savoryleaf aster, flaxleaf whitetop aster
  Ionactis stenomeres (A. Gray) Greene -- accepted -- Rocky Mountain aster
  Ismelia Cass. -- accepted
  Ismelia carinata (Schousb.) Sch. Bip. -- accepted -- tricolor daisy
  Isocarpha R. Br. -- accepted -- pearlhead, isocarpha
  Isocarpha oppositifolia (L.) Cass. -- accepted -- Rio Grande pearlhead
  Isocarpha oppositifolia var. achyranthes (DC.) D.J. Keil & Stuessy -- accepted
  Isocarpha oppositifolia var. oppositifolia (L.) Cass. -- accepted
  Isocoma Nutt. -- accepted -- goldenbush, isocoma, jimmyweed
  Isocoma acradenia (Greene) Greene -- accepted -- alkali goldenbush, alkali jimmyweed
  Isocoma acradenia ssp. acradenia Greene -- not accepted -- alkali goldenbush
  Isocoma acradenia ssp. eremophila (Greene) R.M. Beauch. -- not accepted
  Isocoma acradenia var. acradenia (Greene) Greene -- accepted -- alkali goldenbush, alkali goldenweed
  Isocoma acradenia var. bracteosa (Greene) G.L. Nesom -- accepted -- alkali goldenbush
  Isocoma acradenia var. eremophila (Greene) G.L. Nesom -- accepted -- alkali goldenbush, goldenweed
  Isocoma arguta Greene -- accepted -- Carquinez goldenbush
  Isocoma azteca G.L. Nesom -- accepted -- Aztec goldenbush
  Isocoma bracteosa Greene -- not accepted
  Isocoma coronopifolia (A. Gray) Greene -- accepted -- common goldenbush, goldenweed
  Isocoma coronopifolia var. coronopifolia (Gray) Greene -- not accepted -- common jimmyweed
  Isocoma coronopifolia var. pedicellata (Greene) G.L. Nesom -- not accepted -- common jimmyweed
  Isocoma drummondii (Torr. & A. Gray) Greene -- accepted -- Drummond's goldenbush, Drummond's goldenweed, Drummond's jimmyweed
  Isocoma eremophila Greene -- not accepted
  Isocoma humilis G.L. Nesom -- accepted -- Zion goldenbush
  Isocoma megalantha Shinners -- not accepted
  Isocoma menziesii (Hook. & Arn.) G.L. Nesom -- accepted -- Menzies' goldenbush
  Isocoma menziesii var. decumbens (Greene) G.L. Nesom -- accepted -- Menzies' goldenbush
  Isocoma menziesii var. diabolica G.L. Nesom -- accepted -- Menzies' goldenbush
  Isocoma menziesii var. menziesii (Hook. & Arn.) G.L. Nesom -- accepted -- Menzies' goldenbush
  Isocoma menziesii var. sedoides (Greene) G.L. Nesom -- accepted -- Menzies' goldenbush
  Isocoma menziesii var. vernonioides (Nutt.) G.L. Nesom -- accepted -- Menzies' goldenbush
  Isocoma oxyphylla Greene -- not accepted
  Isocoma palmeri (A. Gray) Shinners -- not accepted
  Isocoma pedicellata Greene -- not accepted
  Isocoma pluriflora (Torr. & A. Gray) Greene -- accepted -- southern goldenbush, rayless goldenrod, southern jimmyweed
  Isocoma rusbyi Greene -- accepted -- Rusby's goldenbush
  Isocoma tenuisecta Greene -- accepted -- burroweed, burrow goldenweed
  Isocoma veneta (Kunth) Greene -- accepted -- jimmyweed
  Isocoma veneta var. furfuracea (Greene) R.M. Beauch. -- not accepted
  Isocoma veneta var. oxyphylla (Greene) R.M. Beauch. -- not accepted
  Isocoma veneta var. sedoides (Greene) Jeps. -- not accepted
  Isocoma veneta var. vernonioides (Nutt.) Jeps. -- not accepted
  Isocoma vernonioides Nutt. -- not accepted
  Isocoma wrightii (A. Gray) Rydb. -- not accepted
  Isopappus divaricatus (Nutt.) Torr. & A. Gray -- not accepted
  Isopappus hookerianus Torr. & A. Gray -- not accepted
  Isopappus validus Rydb. -- not accepted
  Iva L. -- accepted -- marsh elder, iva, marshelder, sumpweed
  Iva acerosa (Nutt.) R.C. Jacks. -- not accepted -- copperweed
  Iva ambrosiifolia (A. Gray) A. Gray -- not accepted -- ragged marsh-elder, ragged marshelder, rag sumpweed
  Iva angustifolia Nutt. ex DC. -- accepted -- narrowleaf marsh elder, Texas marsh elder, narrowleaf marshelder, narrowleaf sumpweed
  Iva angustifolia var. latior Shinners -- not accepted
  Iva annua L. -- accepted -- annual marsh elder, annual marsh-elder, annual marshelder, seacoast sumpweed
  Iva annua var. annua L. -- not accepted -- annual marsh-elder, annual marshelder
  Iva annua var. caudata (Small) R.C. Jacks. -- not accepted -- annual marshelder
  Iva annua var. macrocarpa (S.F. Blake) R.C. Jacks. -- not accepted -- annual marshelder
  Iva asperifolia Less. -- accepted -- Pensacola marsh elder, Pensacola marshelder
  Iva axillaris Pursh -- accepted -- povertyweed, deer-root, poverty sumpweed, lesser marshelder, mouseear povertyweed, poverty weed, smallflowered marshelder
  Iva axillaris ssp. robustior (Hook.) Bassett -- not accepted
  Iva axillaris var. axillaris Pursh -- not accepted
  Iva axillaris var. robustior Hook. -- not accepted
  Iva caudata Small -- not accepted
  Iva cheiranthifolia Kunth -- accepted -- fly marsh elder, fly marshelder
  Iva ciliata Willd. -- not accepted
  Iva ciliata var. macrocarpa S.F. Blake -- not accepted
  Iva dealbata A. Gray -- not accepted -- woolly marsh-elder, woolly marshelder
  Iva frutescens L. -- accepted -- Jesuit's bark, bigleaf sumpweed
  Iva frutescens ssp. frutescens L. -- not accepted -- Jesuit's bark
  Iva frutescens ssp. oraria (Bartlett) R.C. Jacks. -- not accepted -- Jesuit's bark
  Iva frutescens var. oraria (Bartlett) Fernald & Grisc. -- not accepted
  Iva hayesiana A. Gray -- accepted -- San Diego povertyweed
  Iva imbricata Walter -- accepted -- seacoast marsh elder, seacoast marshelder
  Iva microcephala Nutt. -- accepted -- piedmont marsh elder, piedmont marshelder
  Iva nevadensis M.E. Jones -- not accepted -- Nevada sumpweed, Nevada povertyweed
  Iva texensis R.C. Jacks. -- not accepted -- narrowleaf sumpweed, Texas marshelder
  Iva xanthifolia Nutt. -- not accepted -- rag sumpweed, carelessweed, burweed marshelder, false ragweed, giant marshelder, horseweed, marshelder, giant sumpweed
  Ixeris (Cass.) Cass. -- accepted -- ixeris
  Ixeris stolonifera A. Gray -- accepted -- creeping lettuce
  Jacea pratensis Lam. -- not accepted
  Jacobaea Burm. -- accepted
  Jacobaea aquatica (Hill) P. Gaertn., B. Mey. & Scherb. -- accepted -- water ragwort
  Jacobaea aquatica var. aquatica (Hill) P. Gaertn., B. Mey. & Scherb. -- accepted
  Jacobaea aquatica var. erratica (Bertol.) Pelser & Meijden -- accepted
  Jacobaea cannabifolia (Less.) E. Wiebe -- accepted -- Aleutian ragwort
  Jacobaea erucifolia (L.) P. Gaertn., B. Mey. & Scherb. -- accepted -- hoary ragwort
  Jacobaea maritima (L.) Pelser & Meijden -- accepted -- silver ragwort, dusty miller
  Jacobaea vulgaris Gaertn. -- accepted -- stinking willie
  Jamesianthus S.F. Blake & Sherff -- accepted -- jamesianthus
  Jamesianthus alabamensis S.F. Blake & Sherff -- accepted -- Alabama warbonnet
  Jaumea Pers. -- accepted -- jaumea
  Jaumea carnosa (Less.) A. Gray -- accepted -- marsh jaumea
  Jefea Strother -- accepted -- jefea
  Jefea brevifolia (A. Gray) Strother -- accepted -- shortleaf jefea, shorthorn zexmenia
  Jensia B.G. Baldw. -- accepted
  Jensia rammii (Greene) B.G. Baldw. -- accepted -- Ramm's madia
  Jensia yosemitana (Parry ex A. Gray) B.G. Baldw. -- accepted -- Yosemite tarweed
  Kalimeris (Cass.) Cass. -- accepted -- aster
  Kalimeris indica (L.) Sch. Bip. -- accepted -- Indian aster
  Kalimeris mongolica (Franch.) Kitam. -- accepted
  Keerlia bellidifolia A. Gray & Engelm. -- not accepted
  Keerlia effusa A. Gray -- not accepted
  Keerlia skirrhobasis DC. -- not accepted
  Keysseria Lauterb. -- accepted
  Keysseria erici (Forbes) Cabrera -- accepted -- Alakai Swamp island-daisy
  Keysseria helenae (Forbes & Lydgate) Cabrera -- accepted -- Mt. Waialeale island-daisy
  Keysseria lavandula H. St. John -- not accepted
  Keysseria maviensis (H. Mann) Cabrera -- accepted -- Howaiaulu island-daisy
  Kleinia Mill. -- accepted
  Kleinia anteuphorbium (L.) Haw. -- accepted
  Kleinia glandulosa Moc. & Sessé -- not accepted
  Kleinia ruderalis Jacq. -- not accepted
  Koanophyllon Arruda -- accepted -- thoroughwort
  Koanophyllon dolicholepis (Urb.) R.M. King & H. Rob. -- accepted -- oreganillo
  Koanophyllon droserolepis (B.L. Rob.) R.M. King & H. Rob. -- accepted -- Monte Torrecilla thoroughwort
  Koanophyllon palmeri (A. Gray) R.M. King & H. Rob. -- accepted -- Palmer's umbrella thoroughwort
  Koanophyllon polyodon (Urb.) R.M. King & H. Rob. -- accepted -- islandthicket thoroughwort
  Koanophyllon solidaginifolium (A. Gray) R.M. King & H. Rob. -- accepted -- shrubby thoroughwort
  Koanophyllon villosum (Sw.) R.M. King & H. Rob. -- accepted -- Florida Keys thoroughwort
  Koyamacalia auriculata (DC.) H. Rob. & Brettell -- not accepted -- koyamacalia
  Krigia Schreb. -- accepted -- dwarfdandelion, krigia
  Krigia amplexicaulis (Michx.) Nutt. -- not accepted
  Krigia biflora (Walter) S.F. Blake -- accepted -- twoflower dwarfdandelion, two-flower dwarf-dandelion, tall dwarfdandelion
  Krigia biflora ssp. glandulifera (Fernald) Iltis -- not accepted
  Krigia biflora var. biflora (Walter) S.F. Blake -- not accepted -- twoflower dwarfdandelion
  Krigia biflora var. viridis (Standl.) Kim -- not accepted -- twoflower dwarfdandelion
  Krigia caespitosa (Raf.) K.L. Chambers -- accepted -- weedy dwarfdandelion
  Krigia caespitosa var. caespitosa (Raf.) K.L. Chambers -- accepted
  Krigia caespitosa var. gracilis (DC.) K.L. Chambers -- accepted -- Texas dwarfdandelion
  Krigia cespitosa (Raf.) K.L. Chambers -- not accepted -- weedy dwarfdandelion
  Krigia dandelion (L.) Nutt. -- accepted -- potato dwarfdandelion, tuber dwarfdandelion, tuber dandelion
  Krigia gracilis (DC.) Shinners -- not accepted
  Krigia montana (Michx.) Nutt. -- accepted -- mountain dwarfdandelion
  Krigia occidentalis Nutt. -- accepted -- western dwarfdandelion
  Krigia oppositifolia Raf. -- not accepted
  Krigia virginica (L.) Willd. -- accepted -- Virginia dwarfdandelion
  Krigia wrightii (A. Gray) K.L. Chambers ex Kim -- accepted -- Wright's dwarfdandelion
  Kuhnia chlorolepis Woot. & Standl. -- not accepted
  Kuhnia eupatorioides L. -- not accepted
  Kuhnia eupatorioides var. angustifolia Raf. -- not accepted
  Kuhnia eupatorioides var. chlorolepis (Woot. & Standl.) Cronquist -- not accepted
  Kuhnia eupatorioides var. corymbulosa Torr. & A. Gray -- not accepted
  Kuhnia eupatorioides var. floridana R.W. Long -- not accepted
  Kuhnia eupatorioides var. gracilis Torr. & A. Gray -- not accepted
  Kuhnia eupatorioides var. gracillima A. Gray -- not accepted
  Kuhnia eupatorioides var. ozarkana Shinners -- not accepted
  Kuhnia eupatorioides var. pyramidalis Raf. -- not accepted
  Kuhnia eupatorioides var. texana Shinners -- not accepted
  Kuhnia glutinosa Elliot -- not accepted
  Kuhnia hitchcockii A. Nelson -- not accepted
  Kuhnia leptophylla Scheele -- not accepted
  Kuhnia leptophylla var. mexicana Shinners -- not accepted
  Kuhnia microphylla Shinners -- not accepted
  Kuhnia mosieri Small -- not accepted
  Kuhnia rosemarinifolia Vent. -- not accepted
  Kuhnia rosemarinifolia var. chlorolepis (Woot. & Standl.) S.F. Blake -- not accepted
  Kuhnia rosmarinifolia Vent. -- not accepted
  Kuhnia rosmarinifolia var. chlorolepis (Woot. & Standl.) S.F. Blake -- not accepted
  Kuhnia shaffneri A. Gray -- not accepted
  Kyhosia B.G. Baldw. -- accepted
  Kyhosia bolanderi (A. Gray) B.G. Baldw. -- accepted -- Bolander's madia
  Lacinaria acidota (Engelm. & A. Gray) Kuntze -- not accepted
  Lacinaria aspera (Michx.) Greene -- not accepted
  Lacinaria aspera var. spheroidea (Michx.) Alexander -- not accepted
  Lacinaria boykinii (Torr. & A. Gray) Kuntze -- not accepted
  Lacinaria chapmanii (Torr. & A. Gray) Kuntze -- not accepted
  Lacinaria chlorolepis Small -- not accepted
  Lacinaria cylindracea (Michx.) Kuntze -- not accepted
  Lacinaria elegans (Walter) Kuntze -- not accepted
  Lacinaria elegantula Greene -- not accepted
  Lacinaria flabellata Small -- not accepted
  Lacinaria garberi (A. Gray) Kuntze -- not accepted
  Lacinaria gracilis (Pursh) Kuntze -- not accepted
  Lacinaria graminifolia (Willd.) Kuntze -- not accepted
  Lacinaria helleri (Porter) Porter ex A. Heller -- not accepted
  Lacinaria lancifolia Greene -- not accepted
  Lacinaria laxa Small -- not accepted
  Lacinaria ligulistylis A. Nelson -- not accepted
  Lacinaria microcephala Small -- not accepted
  Lacinaria nashii Small -- not accepted
  Lacinaria pauciflora (Pursh) Kuntze -- not accepted
  Lacinaria pilosa (Aiton) A. Heller -- not accepted
  Lacinaria pilosa auct. non (Aiton) A. Heller -- not accepted
  Lacinaria punctata (Hook.) Kuntze -- not accepted
  Lacinaria pycnostachya (Michx.) Kuntze -- not accepted
  Lacinaria regimontis Small -- not accepted
  Lacinaria ruthii Alexander -- not accepted
  Lacinaria scariosa (L.) Hill -- not accepted
  Lacinaria scariosa var. nieuwlandii Lunell -- not accepted
  Lacinaria secunda (Elliot) Small -- not accepted
  Lacinaria shortii Alexander -- not accepted
  Lacinaria smallii Britton -- not accepted
  Lacinaria spicata (L.) Kuntze -- not accepted
  Lacinaria squarrosa (L.) Hill -- not accepted
  Lacinaria squarrosa var. intermedia (Lunell) DC. -- not accepted
  Lacinaria tenuifolia (Nutt.) Kuntze -- not accepted
  Lacinaria tracyi Alexander -- not accepted
  Lactuca L. -- accepted -- lettuce
  Lactuca biennis (Moench) Fernald -- accepted -- tall blue lettuce, wild blue lettuce
  Lactuca campestris Greene -- not accepted
  Lactuca campestris var. typica Wiegand -- not accepted
  Lactuca canadensis L. -- accepted -- Canada lettuce, Florida blue lettuce, wild lettuce
  Lactuca canadensis var. canadensis L. -- not accepted -- Canada lettuce
  Lactuca canadensis var. integrifolia (Bigelow) Torr. & A. Gray -- not accepted
  Lactuca canadensis var. latifolia Kuntze -- not accepted -- Canada lettuce
  Lactuca canadensis var. longifolia (Michx.) Farw. -- not accepted -- Canada lettuce
  Lactuca canadensis var. obovata Wiegand -- not accepted -- Canada lettuce
  Lactuca canadensis var. typica Wiegand -- not accepted
  Lactuca floridana (L.) Gaertn. -- accepted -- woodland lettuce, Florida lettuce
  Lactuca floridana var. floridana (L.) Gaertn. -- not accepted -- woodland lettuce
  Lactuca floridana var. villosa (Jacq.) Cronquist -- not accepted -- woodland lettuce
  Lactuca graminifolia Michx. -- accepted -- grassleaf lettuce, grass-leaf lettuce
  Lactuca graminifolia var. arizonica McVaugh -- not accepted -- grassleaf lettuce
  Lactuca graminifolia var. graminifolia Michx. -- accepted -- grassleaf lettuce
  Lactuca hirsuta Muhl. ex Nutt. -- accepted -- hairy lettuce
  Lactuca hirsuta var. albiflora (Torr. & A. Gray) Shinners -- not accepted -- hairy lettuce
  Lactuca hirsuta var. hirsuta Muhl. ex Nutt. -- not accepted -- hairy lettuce
  Lactuca hirsuta var. sanguinea (Bigelow) Fernald -- not accepted -- hairy wild lettuce, hairy lettuce
  Lactuca indica L. -- accepted -- Indian lettuce
  Lactuca intybacea Jacq. -- not accepted
  Lactuca ludoviciana (Nutt.) Riddell -- accepted -- biannual lettuce, Louisiana lettuce, wild lettuce
  Lactuca muralis (L.) Fresen. -- not accepted
  Lactuca oblongifolia Nutt. -- not accepted
  Lactuca pulchella (Pursh) DC. -- not accepted -- blue lettuce
  Lactuca sagittifolia Elliot -- not accepted
  Lactuca saligna L. -- accepted -- willowleaf lettuce, willow-leaf lettuce
  Lactuca saligna var. runcinata Gren. & Godr. -- not accepted
  Lactuca sativa L. -- accepted -- garden lettuce, lettuce
  Lactuca scariola L. -- not accepted
  Lactuca scariola var. integrata Gren. & Godr. -- not accepted
  Lactuca scariola var. integrifolia (Bogenh.) G. Beck -- not accepted
  Lactuca serriola L. -- accepted -- prickly lettuce, China lettuce, wild lettuce
  Lactuca spicata auct. non (Lam.) Hitchc. -- not accepted
  Lactuca spicata var. integrifolia (Torr. & A. Gray) Britton -- not accepted
  Lactuca steelei Britton -- not accepted
  Lactuca stolonifera (A. Gray) Maxim. -- not accepted
  Lactuca tatarica (L.) C.A. Mey. -- not accepted -- Russian blue lettuce, blue lettuce, chicory lettuce
  Lactuca tatarica ssp. pulchella (Pursh) Stebbins -- not accepted
  Lactuca tatarica var. heterophylla (Nutt.) B. Boivin -- not accepted
  Lactuca tatarica var. pulchella (Pursh) Breitung -- not accepted -- Russian blue lettuce, blue wild lettuce, chicory lettuce, blue lettuce
  Lactuca villosa Jacq. -- not accepted
  Lactuca virosa L. -- accepted -- bitter lettuce
  Lactuca X morssii B.L. Rob. (pro sp.) -- accepted -- Morss' lettuce
  Laennecia Cass. -- accepted -- laennecia
  Laennecia coulteri (A. Gray) G.L. Nesom -- accepted -- conyza, annual horsetail, Coulter's horseweed
  Laennecia eriophylla (A. Gray) G.L. Nesom -- accepted -- Cochise marshtail
  Laennecia filaginoides DC. -- accepted -- Trans-Pecos marshtail
  Laennecia schiedeana (Less.) G.L. Nesom -- accepted -- pineland marshtail
  Laennecia sophiifolia (Kunth) G.L. Nesom -- accepted -- leafy marshtail
  Laennecia turnerorum G.L. Nesom -- accepted -- Turner's marshtail
  Lagascea Cav. -- accepted -- lagascea
  Lagascea decipiens Hemsl. -- accepted -- doll's head, lagascea
  Lagascea mollis Cav. -- accepted -- silkleaf, acuate
  Lagenifera Cass. -- not accepted -- island-daisy
  Lagenifera erici Forbes -- not accepted -- Alakai Swamp island-daisy
  Lagenifera helenae Forbes & Lydgate -- not accepted -- Mt. Waialeale island-daisy
  Lagenifera maviensis H. Mann -- not accepted -- Howaiaulu island-daisy
  Lagenophora viridis H. St. John -- not accepted
  Lagophylla Nutt. -- accepted -- hareleaf
  Lagophylla congesta Greene -- not accepted
  Lagophylla dichotoma Benth. -- accepted -- forked hareleaf
  Lagophylla glandulosa A. Gray -- accepted -- glandular hareleaf
  Lagophylla glandulosa ssp. glandulosa A. Gray -- not accepted -- glandular hareleaf
  Lagophylla glandulosa ssp. serrata (Greene) D.D. Keck -- not accepted
  Lagophylla minor (D.D. Keck) D.D. Keck -- accepted -- lesser hareleaf
  Lagophylla ramosissima Nutt. -- accepted -- branched lagophylla, common hareleaf
  Lagophylla ramosissima ssp. congesta (Greene) D.D. Keck -- not accepted -- branched lagophylla
  Lagophylla ramosissima ssp. ramosissima Nutt. -- not accepted -- branched lagophylla, branched hareleaf
  Lagophylla scabrella (E. Drew) M.E. Jones -- not accepted
  Laphamia angustifolia A. Gray -- not accepted
  Laphamia angustifolia ssp. laciniata (A. Gray) Niles -- not accepted
  Laphamia bisetosa Torr. ex A. Gray -- not accepted
  Laphamia cernua Greene -- not accepted
  Laphamia cinerea A. Gray -- not accepted
  Laphamia cochisensis Niles -- not accepted
  Laphamia congesta M.E. Jones -- not accepted
  Laphamia dissecta Torr. -- not accepted
  Laphamia fastigiata Brandegee -- not accepted
  Laphamia gilensis M.E. Jones -- not accepted
  Laphamia gilensis ssp. longilobus Niles -- not accepted
  Laphamia gracilis M.E. Jones -- not accepted
  Laphamia halimifolia A. Gray -- not accepted
  Laphamia halimifolia ssp. lindheimeri (A. Gray) Niles -- not accepted
  Laphamia intricata Brandegee -- not accepted
  Laphamia inyoensis Ferris -- not accepted
  Laphamia megalocephala S. Watson -- not accepted
  Laphamia megalocephala ssp. intricata (Brandegee) D.D. Keck -- not accepted
  Laphamia palmeri A. Gray -- not accepted
  Laphamia palmeri var. tenella M.E. Jones -- not accepted
  Laphamia quinqueflora Steyerm. -- not accepted
  Laphamia rotundata Rydb. -- not accepted
  Laphamia rupestris A. Gray -- not accepted
  Laphamia saxicola Eastw. -- not accepted
  Laphamia stansburii A. Gray -- not accepted
  Laphamia stansburyi A. Gray -- not accepted
  Laphamia staurophylla Barneby -- not accepted
  Laphamia villosa S.F. Blake -- not accepted
  Lappa major Gaertn. -- not accepted
  Lappa minor Hill -- not accepted
  Lapsana L. -- accepted -- nipplewort
  Lapsana apogonoides Maxim. -- not accepted -- Japanese nipplewort
  Lapsana communis L. -- accepted -- common nipplewort, nipplewort
  Lapsanastrum J.K. Pak & K. Bremer -- accepted -- nipplewort
  Lapsanastrum apogonoides (Maxim.) J.H. Pak & K. Bremer -- accepted -- Japanese nipplewort
  Lasallea adnata (Nutt.) Semple & L. Brouillet -- not accepted
  Lasallea caroliniana (Walter) Semple & L. Brouillet -- not accepted
  Lasallea concolor (L.) Semple & L. Brouillet -- not accepted
  Lasallea ericoides (L.) Semple & L. Brouillet -- not accepted
  Lasallea falcata (Lindl.) Semple & L. Brouillet -- not accepted
  Lasallea grandiflora (L.) Semple & L. Brouillet -- not accepted
  Lasallea novae-angliae (L.) Semple & L. Brouillet -- not accepted
  Lasallea oblongifolia (Nutt.) Semple & L. Brouillet -- not accepted
  Lasallea patens (Aiton) Semple & L. Brouillet -- not accepted
  Lasallea sericea (Vent.) Greene -- not accepted
  Lasallea sericea ssp. pratensis (Raf.) Semple & L. Brouillet -- not accepted
  Lasallea walteri (Alexander) Semple & L. Brouillet -- not accepted
  Lasallea X amethystina (Nutt.) Semple & L. Brouillet -- not accepted
  Lasianthaea DC. -- accepted -- lasianthaea
  Lasianthaea podocephala (A. Gray) K. Becker -- accepted -- San Pedro daisy
  Lasiospermum M. Lagasca -- accepted -- cocoonhead
  Lasiospermum bipinnatum (Thunb.) Druce -- accepted -- cocoonhead
  Lasiospermum radiatum Trevir. -- not accepted
  Lasthenia Cass. -- accepted -- goldfields, lasthenia
  Lasthenia burkei (Greene) Greene -- accepted -- Burke's baeria, Burke's goldfields
  Lasthenia californica DC. ex Lindl. -- accepted -- California goldfields, goldfields
  Lasthenia californica ssp. bakeri (J.T. Howell) R. Chan -- accepted -- Baker's goldfields
  Lasthenia californica ssp. californica DC. ex Lindl. -- accepted -- California goldfields
  Lasthenia californica ssp. macrantha (A. Gray) R. Chan -- accepted -- perennial goldfields
  Lasthenia chrysantha (Greene ex A. Gray) Greene -- accepted -- alkali sink goldfields
  Lasthenia chrysostoma (Fisch. & C.A. Mey.) Greene -- not accepted
  Lasthenia conjugens Greene -- accepted -- Contra Costa goldfields
  Lasthenia coronaria (Nutt.) Ornduff -- accepted -- royal goldfields
  Lasthenia debilis (Greene ex A. Gray) Ornduff -- accepted -- Greene's goldfields
  Lasthenia ferrisiae Ornduff -- accepted -- Ferris' goldfields
  Lasthenia fremontii (Torr. ex A. Gray) Greene -- accepted -- Fremont's goldfields
  Lasthenia glaberrima DC. -- accepted -- smooth goldfields
  Lasthenia glabrata Lindl. -- accepted -- yellowray goldfields
  Lasthenia glabrata ssp. coulteri (A. Gray) Ornduff -- accepted -- Coulter's goldfields
  Lasthenia glabrata ssp. glabrata Lindl. -- accepted -- yellowray goldfields
  Lasthenia glabrata var. coulteri A. Gray -- not accepted
  Lasthenia gracilis (DC.) Greene -- accepted -- needle goldfields
  Lasthenia leptalea (A. Gray) Ornduff -- accepted -- Salinas Valley goldfields
  Lasthenia macrantha (A. Gray) Greene -- not accepted -- perennial goldfields
  Lasthenia macrantha ssp. bakeri (J.T. Howell) Ornduff -- not accepted -- Baker's goldfields
  Lasthenia macrantha ssp. macrantha (A. Gray) Greene -- not accepted -- perennial goldfields
  Lasthenia macrantha ssp. prisca Ornduff -- not accepted -- perennial goldfields
  Lasthenia maritima (A. Gray) Ornduff -- accepted -- seaside goldfields
  Lasthenia microglossa (DC.) Greene -- accepted -- smallray goldfields
  Lasthenia minor (DC.) Ornduff -- accepted -- coastal goldfields
  Lasthenia minor ssp. maritima (A. Gray) Ornduff -- not accepted
  Lasthenia minor var. maritima (A. Gray) Cronquist -- not accepted
  Lasthenia minor var. minor (DC.) Ornduff -- not accepted
  Lasthenia ornduffii R. Chan -- accepted -- Ornduff's goldfields
  Lasthenia platycarpha (A. Gray) Greene -- accepted -- alkali goldfields
  Launaea Cass. -- accepted -- launaea
  Launaea cornuta (Hochst. ex Oliv. & Hiern) C. Jeffrey -- accepted
  Launaea intybacea (Jacq.) P. Beauv. -- accepted -- achicoria azul
  Layia Hook. & Arn. ex DC. -- accepted -- tidytips
  Layia carnosa (Nutt.) Torr. & A. Gray -- accepted -- beach tidytips, beach layia
  Layia chrysanthemoides (DC.) A. Gray -- accepted -- smooth tidytips
  Layia chrysanthemoides ssp. chrysanthemoides (DC.) Gray -- not accepted -- smooth tidytips
  Layia chrysanthemoides ssp. maritima D.D. Keck -- not accepted
  Layia discoidea D.D. Keck -- accepted -- rayless tidytips
  Layia fremontii (Torr. & A. Gray) A. Gray -- accepted -- Fremont's tidytips
  Layia gaillardioides (Hook. & Arn.) DC. -- accepted -- woodland tidytips
  Layia glandulosa (Hook.) Hook. & Arn. -- accepted -- whitedaisy tidytips, white tidytips
  Layia glandulosa ssp. glandulosa (Hook.) Hook. & Arn. -- not accepted -- whitedaisy tidytips
  Layia glandulosa ssp. lutea D.D. Keck -- not accepted
  Layia heterotricha (DC.) Hook. & Arn. -- accepted -- paleyellow tidytips
  Layia hieracioides (DC.) Hook. & Arn. -- accepted -- tall tidytips
  Layia jonesii A. Gray -- accepted -- Jones' tidytips
  Layia leucopappa D.D. Keck -- accepted -- Comanche Point tidytips
  Layia munzii D.D. Keck -- accepted -- Munz's tidytips
  Layia paniculata D.D. Keck -- not accepted
  Layia pentachaeta A. Gray -- accepted -- Sierra tidytips
  Layia pentachaeta ssp. albida D.D. Keck -- accepted -- Sierra tidytips
  Layia pentachaeta ssp. pentachaeta A. Gray -- accepted -- Sierra tidytips
  Layia platyglossa (Fisch. & C.A. Mey.) A. Gray -- accepted -- coastal tidytips
  Layia platyglossa ssp. campestris D.D. Keck -- not accepted
  Layia platyglossa ssp. platyglossa (Fisch. & C.A. Mey.) A. Gray -- not accepted -- coastal tidytips
  Layia platyglossa var. breviseta A. Gray -- not accepted
  Layia septentrionalis D.D. Keck -- accepted -- Colusa tidytips
  Layia ziegleri Munz -- not accepted
  Leibnitzia Cass. -- accepted -- sunbonnets, leibnitzia
  Leibnitzia lyrata (D. Don) G.L. Nesom -- not accepted -- Seeman's sunbonnets
  Leibnitzia lyrata (Sch. Bip.) G.L. Nesom -- accepted -- Seeman's sunbonnets
  Leibnitzia seemannii (Sch. Bip.) G.L. Nesom -- not accepted -- Seeman's sunbonnets
  Leiodon latifolius (Michx.) Shuttlw. -- not accepted
  Lembertia Greene -- not accepted -- lembertia
  Lembertia congdonii (A. Gray) Greene -- not accepted -- San Joaquin wooly-threads, San Joaquin woollythread
  Leontodon L. -- accepted -- hawkbit, leontodon
  Leontodon autumnalis L. -- accepted -- fall dandelion
  Leontodon autumnalis ssp. autumnalis L. -- not accepted -- fall dandelion
  Leontodon autumnalis ssp. pratensis (Link) Arcang. -- not accepted -- fall dandelion
  Leontodon autumnalis var. pratensis (Link) W.D.J. Koch -- not accepted
  Leontodon danubialis Jacq. -- not accepted
  Leontodon erythrospermum (Andrz. ex Besser) Britton -- not accepted
  Leontodon hastilis L. -- not accepted
  Leontodon hastilis var. glabratus W.D.J. Koch -- not accepted
  Leontodon hastilis var. vulgaris W.D.J. Koch -- not accepted
  Leontodon hirtus auct. non L. -- not accepted -- rough hawkbit
  Leontodon hispidus L. -- accepted -- bristly hawkbit, rough hawkbit
  Leontodon hispidus ssp. danubialis (Jacq.) Simonkai -- not accepted -- bristly hawkbit
  Leontodon hispidus ssp. hispidus L. -- not accepted -- bristly hawkbit
  Leontodon hispidus var. glabratus (W.D.J. Koch) Bisch. -- not accepted
  Leontodon latiloba (DC.) Britton -- not accepted
  Leontodon leysseri (Wallr.) G. Beck -- not accepted
  Leontodon muelleri (Sch. Bip.) Fiori -- accepted -- Mueller's hawkbit
  Leontodon nudicaulis (L.) Banks ex Schinz & R. Keller -- not accepted
  Leontodon nudicaulis ssp. taraxacoides (Vill.) Schinz & Thell. -- not accepted
  Leontodon saxatilis Lam. -- accepted -- hairy hawkbit
  Leontodon saxatilis ssp. longirostris (Finch & Sell) P. Silva -- accepted
  Leontodon saxatilis ssp. saxatilis Lam. -- accepted -- lesser hawkbit
  Leontodon taraxacoides (Vill.) Mérat -- not accepted -- lesser hawkbit, hairy hawkbit
  Leontodon taraxacoides ssp. longirostris Finch & Sell -- not accepted -- lesser hawkbit
  Leontodon taraxacoides ssp. taraxacoides (Vill.) Mérat -- not accepted -- lesser hawkbit
  Leontodon taraxacum L. -- not accepted
  Lepachys columnaris (Pursh) Torr. & A. Gray -- not accepted
  Lepachys columnifera (Nutt.) J.F. Macbr. -- not accepted
  Lepachys peduncularis Torr. & A. Gray -- not accepted
  Lepachys peduncularis var. picta A. Gray -- not accepted
  Lepachys pinnata (Vent.) Torr. & A. Gray -- not accepted
  Lepidanthus suaveolens (Pursh) Nutt. -- not accepted
  Lepidaploa (Cass.) Cass. -- accepted
  Lepidaploa borinquensis (Urb.) H. Rob. -- accepted -- Puerto Rico ironweed
  Lepidaploa glabra (Willd.) H. Rob. -- accepted -- Santa Maria
  Lepidaploa proctorii (Urbatsch) H. Rob. -- accepted -- Proctor's ironweed
  Lepidaploa sericea (Rich.) H. Rob. -- accepted -- longshoot
  Lepidospartum (A. Gray) A. Gray -- accepted -- broomsage
  Lepidospartum burgessii B.L. Turner -- accepted -- Burgess' broomsage
  Lepidospartum latisquamum S. Watson -- accepted -- Nevada broomsage
  Lepidospartum squamatum (A. Gray) A. Gray -- accepted -- California broomsage, California scalebroom
  Lepidospartum squamatum var. palmeri (A. Gray) L.C. Wheeler -- not accepted
  Lepidotheca suaveolens (Pursh) Nutt. -- not accepted
  Leptilon bonariense (L.) Small -- not accepted
  Leptilon canadense (L.) Britton -- not accepted
  Leptilon chinense (Jacq.) Britton -- not accepted
  Leptilon divaricatum (Michx.) Raf. -- not accepted
  Leptilon integrifolium Woot. & Standl. -- not accepted
  Leptilon linifolium (Willd.) Small -- not accepted
  Leptilon pusillum (Nutt.) Britton -- not accepted
  Leptopoda fimbriata Torr. & A. Gray non Leptopoda fimbriata (Michx.) Eaton -- not accepted
  Leptoseris sonchoides Nutt. -- not accepted
  Leptosyne bigelovii (A. Gray) A. Gray -- not accepted
  Leptosyne californica Nutt. -- not accepted
  Leptosyne douglasii DC. -- not accepted
  Leptosyne gigantea Kellogg -- not accepted
  Leptosyne hamiltonii Elmer -- not accepted
  Leptosyne stillmanii A. Gray -- not accepted
  Lessingia Cham. -- accepted -- lessingia, vinegarweed
  Lessingia arachnoidea Greene -- accepted -- Crystal Springs lessingia
  Lessingia filaginifolia (Hook. & Arn.) M.A. Lane -- not accepted
  Lessingia filaginifolia var. californica (DC.) M.A. Lane -- not accepted
  Lessingia filaginifolia var. filaginifolia (Hook. & Arn.) M.A. Lane -- not accepted
  Lessingia germanorum Cham. -- accepted -- San Francisco lessingia
  Lessingia germanorum var. germanorum Cham. -- not accepted -- San Francisco vinegarweed
  Lessingia germanorum var. glandulifera (A. Gray) J.T. Howell -- not accepted
  Lessingia germanorum var. lemmonii (A. Gray) J.T. Howell -- not accepted
  Lessingia germanorum var. parvula (Greene) J.T. Howell -- not accepted
  Lessingia germanorum var. pectinata (Greene) J.T. Howell -- not accepted
  Lessingia germanorum var. peirsonii J.T. Howell -- not accepted
  Lessingia germanorum var. ramulosissima (A. Nelson) J.T. Howell -- not accepted
  Lessingia germanorum var. tenuis (A. Gray) J.T. Howell -- not accepted
  Lessingia germanorum var. tomentosa (Greene) J.T. Howell -- not accepted
  Lessingia glandulifera A. Gray -- accepted -- valley lessingia
  Lessingia glandulifera var. glandulifera A. Gray -- accepted -- valley lessingia, Lemmon's lessingia
  Lessingia glandulifera var. pectinata (Greene) Jeps. -- not accepted -- valley lessingia
  Lessingia glandulifera var. peirsonii (J.T. Howell) Markos -- accepted -- Peirson's lessingia
  Lessingia glandulifera var. tomentosa (Greene) Ferris -- accepted -- Warner Springs lessingia
  Lessingia hololeuca Greene -- accepted -- woollyhead lessingia
  Lessingia hololeuca var. arachnoidea (Greene) J.T. Howell -- not accepted
  Lessingia hololeuca var. hololeuca Greene -- not accepted -- woollyhead vinegarweed
  Lessingia lemmonii A. Gray -- not accepted -- Lemmon's vinegar-weed, Lemmon's lessingia, Lemmon's bladderpod
  Lessingia lemmonii var. lemmonii A. Gray -- not accepted -- Lemmon's lessingia, Lemmon's vinegarweed
  Lessingia lemmonii var. peirsonii (J.T. Howell) Ferris -- not accepted -- Peirson's lessingia
  Lessingia lemmonii var. ramulosissima (A. Nelson) Ferris -- not accepted -- Lemmon's lessingia, Lemmon's vinegarweed
  Lessingia leptoclada A. Gray -- accepted -- Sierra lessingia
  Lessingia micradenia Greene -- accepted -- Mt. Tamalpais lessingia
  Lessingia micradenia var. arachnoidea (Greene) Ferris -- not accepted
  Lessingia micradenia var. glabrata (D.D. Keck) Ferris -- accepted -- smooth lessingia
  Lessingia micradenia var. micradenia Greene -- accepted -- Mt. Tamalpais lessingia
  Lessingia nana A. Gray -- accepted -- dwarf lessingia
  Lessingia nemaclada Greene -- accepted -- slenderstem lessingia, Mendocino lessingia
  Lessingia nemaclada var. albiflora (Eastw.) J.T. Howell -- not accepted -- slenderstem lessingia
  Lessingia nemaclada var. mendocina (Greene) J.T. Howell -- not accepted -- Mendocino lessingia
  Lessingia nemaclada var. nemaclada Greene -- not accepted -- slenderstem lessingia
  Lessingia occidentalis (H.M. Hall) M.A. Lane -- not accepted
  Lessingia pectinata Greene -- accepted -- valley lessingia
  Lessingia pectinata var. pectinata Greene -- accepted
  Lessingia pectinata var. tenuipes (J.T. Howell) Markos -- accepted
  Lessingia ramulosa A. Gray -- accepted -- Sonoma lessingia
  Lessingia ramulosa var. adenophora (Greene) A. Gray -- not accepted -- Sonoma lessingia
  Lessingia ramulosa var. glabrata D.D. Keck -- not accepted
  Lessingia ramulosa var. micradenia (Greene) J.T. Howell -- not accepted
  Lessingia ramulosa var. ramulosa A. Gray -- not accepted -- Sonoma lessingia
  Lessingia tenuis (A. Gray) Coville -- accepted -- spring lessingia
  Lessingia virgata A. Gray -- accepted -- wand lessingia
  Lessingia virgata var. glomerata (Greene) J.T. Howell -- not accepted -- wand lessingia
  Lessingia virgata var. virgata A. Gray -- not accepted -- wand lessingia
  Leucacantha cyanus (L.) Nieuwl. & Lunell -- not accepted
  Leucampyx newberryi A. Gray -- not accepted
  Leucantha solstitialis (L.) Á. Löve & D. Löve -- not accepted
  Leucanthemella Tzvelev -- accepted -- leucanthemella
  Leucanthemella serotina (L.) Tzvelev -- accepted -- giantdaisy
  Leucanthemum Mill. -- accepted -- daisy, leucanthemum
  Leucanthemum arcticum (L) DC -- not accepted
  Leucanthemum integrifolium (Richardson) DC. -- not accepted -- entireleaf daisy
  Leucanthemum ircutianum (Turcz.) DC. -- not accepted
  Leucanthemum lacustre (Brot.) Samp. -- accepted -- Portuguese daisy
  Leucanthemum leucanthemum (L.) Rydb. -- not accepted
  Leucanthemum maximum (Ramond) DC. -- accepted -- max chrysanthemum
  Leucanthemum nipponicum Franch. ex Maxim. -- not accepted -- Nippon daisy
  Leucanthemum serotinum (L.) Stankov -- not accepted
  Leucanthemum vulgare Lam. -- accepted -- oxeye daisy, oxeye-daisy, oxeyedaisy, ox-eye daisy
  Leucanthemum vulgare var. pinnatifidum (Lecoq & Lamotte) Moldenke -- not accepted
  Leucanthemum X superbum (Bergmans ex J.W. Ingram) Bergmans ex Kent. -- accepted -- Shasta daisy
  Leucelene Greene -- not accepted
  Leucelene ericoides (Torr.) Greene -- not accepted
  Leuciva Rydb. -- accepted
  Leuciva dealbata (A. Gray) Rydb. -- accepted -- woolly marsh elder
  Leucopsidium humile Benth. -- not accepted
  Leucosyris carnosa (A. Gray) Greene -- not accepted
  Leucosyris carnosa var. intricata (A. Gray) Cronquist -- not accepted
  Leucosyris spinosa (Benth.) Greene -- not accepted
  Liatris Gaertn. ex Schreb. -- accepted -- blazing star, gayfeather
  Liatris acidota Engelm. & A. Gray -- accepted -- sharp blazing star, sharp gayfeather
  Liatris aestivalis G.L. Nesom & R. O'Kennon -- accepted
  Liatris angustifolia (Bush) Gaiser -- not accepted
  Liatris aspera Michx. -- accepted -- tall blazing star, tall gayfeather, rough gayfeather
  Liatris aspera var. aspera Michx. -- not accepted -- tall blazing star, tall gayfeather
  Liatris aspera var. intermedia (Lunell) Gaiser -- not accepted -- tall blazing star
  Liatris aspera var. salutans (Lunell) Shinners -- not accepted -- tall blazing star, tall gayfeather
  Liatris bebbiana Rydb. -- not accepted
  Liatris borealis Nutt. -- not accepted
  Liatris bracteata Gaiser -- accepted -- bracted blazing star, bracted gayfeather
  Liatris chapmanii Torr. & A. Gray -- accepted -- Chapman's blazing star
  Liatris cokeri Pyne & Stucky -- accepted -- Sandhill's blazing star, Coker's gayfeather
  Liatris compacta (Torr. & A. Gray) Rydb. -- accepted -- scaly blazing star
  Liatris cylindracea Michx. -- accepted -- Ontario blazing star
  Liatris cymosa (H. Ness) K. Schum. -- accepted -- branched blazing star, branched gayfeather
  Liatris densispicata (Bush) Gaiser -- not accepted -- densespike blazing star, densespike gayfeather
  Liatris densispicata var. densispicata (Bush) Gaiser -- not accepted -- densespike blazing star, densespike gayfeather
  Liatris densispicata var. interrupta Gaiser -- not accepted -- densespike blazing star, densespike gayfeather
  Liatris earlei (Greene) K. Schum. -- not accepted
  Liatris elegans (Walter) Michx. -- accepted -- pinkscale blazing star, pinkscale gayfeather
  Liatris elegans var. bridgesii Mayfield -- accepted
  Liatris elegans var. carizzana Gaiser -- accepted -- pinkscale blazing star, pinkscale gayfeather
  Liatris elegans var. elegans (Walter) Michx. -- accepted -- pinkscale blazing star, pinkscale gayfeather
  Liatris elegans var. flabellata (Small) Gaiser -- not accepted -- pinkscale blazing star
  Liatris elegans var. kralii Mayfield -- accepted
  Liatris elegantula (Greene) K. Schum. -- accepted -- shaggy blazing star
  Liatris garberi A. Gray -- accepted -- Garber's blazing star
  Liatris gholsonii L.C. Anderson -- accepted -- Gholson's blazing star
  Liatris glabrata Rydb. -- not accepted
  Liatris glabrata var. alabamensis (Alexander) Shinners -- not accepted
  Liatris glandulosa G.L. Nesom & R. O'Kennon -- accepted -- glandular blazing star
  Liatris gracilis Pursh -- accepted -- slender blazing star
  Liatris graminifolia Willd. -- not accepted
  Liatris graminifolia var. dubia (W. Bartram) A. Gray -- not accepted
  Liatris graminifolia var. elegantula (Greene) K. Schum. -- not accepted
  Liatris graminifolia var. graminifolia Willd. -- not accepted -- grassleaf gayfeather
  Liatris graminifolia var. lasia Fernald & Grisc. -- not accepted
  Liatris graminifolia var. racemosa (DC.) Venard -- not accepted
  Liatris graminifolia var. smallii (Britton) Fernald & Grisc. -- not accepted
  Liatris graminifolia var. virgata (Nutt.) Fernald -- not accepted
  Liatris helleri Porter -- accepted -- Heller's blazing star, turgid blazing star, Heller's blazingstar
  Liatris hirsuta Rydb. -- accepted -- scaly blazing star
  Liatris kansana Britton -- not accepted
  Liatris laevigata (Nutt.) Small -- accepted -- shortleaf blazing star
  Liatris lancifolia (Greene) Kittell -- accepted -- lanceleaf blazing star, lanceleaf gayfeather
  Liatris ligulistylis (A. Nelson) K. Schum. -- accepted -- Rocky Mountain blazing star, Rocky Mountain gayfeather, strap-style gayfeather
  Liatris microcephala (Small) K. Schum. -- accepted -- smallhead blazing star
  Liatris mucronata DC. -- not accepted -- cusp blazing star, narrowleaf gayfeather
  Liatris novae-angliae (Lunell) Shinners -- not accepted
  Liatris novae-angliae var. nieuwlandii (Lunell) Shinners -- not accepted
  Liatris ohlingerae (S.F. Blake) B.L. Rob. -- accepted -- Florida blazing star, scrub blazing star, scrub blazingstar
  Liatris oligocephala J. Allison -- accepted -- Cahaba torch
  Liatris patens Pursh -- accepted
  Liatris pauciflora Pursh -- accepted -- fewflower blazing star
  Liatris pauciflora var. pauciflora Pursh -- accepted
  Liatris pauciflora var. secunda (Elliott) D.B. Ward -- accepted -- piedmont blazing star
  Liatris pilosa (Aiton) Willd. -- accepted -- shaggy blazing star
  Liatris pilosa var. pilosa (Aiton) Willd. -- not accepted -- shaggy blazing star
  Liatris provincialis Godfrey -- accepted -- Godfrey's blazing star
  Liatris punctata Hook. -- accepted -- dotted blazing star, dotted gayfeather
  Liatris punctata var. mexicana Gaiser -- accepted -- Mexican blazing star, Mexican gayfeather
  Liatris punctata var. mucronata (DC.) B.L. Turner -- accepted -- densespike blazing star, cusp blazing star
  Liatris punctata var. nebraskana Gaiser -- not accepted -- Nebraska blazing star, Nebraska gayfeather
  Liatris punctata var. punctata Hook. -- accepted -- dotted blazing star, dotted gayfeather, densespike blazing star
  Liatris punctata var. typica Gaiser -- not accepted
  Liatris pycnostachya Michx. -- accepted -- prairie blazing star, cat-tail gayfeather, Kansas gayfeather
  Liatris pycnostachya var. lasiophylla Shinners -- accepted -- prairie blazing star, cattail gayfeather
  Liatris pycnostachya var. pycnostachya Michx. -- accepted -- prairie blazing star, cattail gayfeather
  Liatris regimontis auct. non (Small) K. Schum. -- not accepted
  Liatris regimontis (Small) K. Schum. -- not accepted -- gayfeather
  Liatris savannensis Kral & G.L. Nesom -- accepted
  Liatris scabra (Greene) K. Schum. -- not accepted
  Liatris scariosa (L.) Willd. -- accepted -- devil's bite
  Liatris scariosa var. nieuwlandii (Lunell) E.G. Voss -- accepted -- Nieuwland's blazing star
  Liatris scariosa var. novae-angliae Lunell -- accepted -- New England blazing star
  Liatris scariosa var. scariosa (L.) Willd. -- accepted -- devil's bite, Virginia blazing star
  Liatris scariosa var. squarrulosa (Michx.) A. Gray -- not accepted
  Liatris scariosa var. virginiana (Lunell) Gaiser -- not accepted -- Virginia blazing star
  Liatris secunda Elliot -- not accepted -- piedmont blazing star
  Liatris spheroidea Michx. -- not accepted -- spherical blazing star
  Liatris spicata (L.) Willd. -- accepted -- dense blazing star
  Liatris spicata var. racemosa DC. -- not accepted -- dense blazing star
  Liatris spicata var. resinosa (Nutt.) Gaiser -- accepted -- dense blazing star
  Liatris spicata var. spicata (L.) Willd. -- accepted -- dense blazing star
  Liatris squarrosa (L.) Michx. -- accepted -- scaly blazing star, scaly gayfeather
  Liatris squarrosa var. alabamensis (Alexander) Gaiser -- not accepted -- scaly gayfeather, Alabama blazing star
  Liatris squarrosa var. compacta Torr. & A. Gray -- not accepted -- scaly blazing star
  Liatris squarrosa var. glabrata (Rydb.) Gaiser -- accepted -- scaly blazing star, scaly gayfeather
  Liatris squarrosa var. gracilenta Gaiser -- not accepted
  Liatris squarrosa var. hirsuta (Rydb.) Gaiser -- not accepted -- scaly blazing star, scaly gayfeather
  Liatris squarrosa var. squarrosa (L.) Michx. -- accepted -- scaly blazing star, Alabama blazing star
  Liatris squarrulosa Michx. -- accepted -- Appalachian blazing star, tall gayfeather, Appalachian gayfeather
  Liatris tenuifolia Nutt. -- accepted -- shortleaf blazing star
  Liatris tenuifolia var. laevigata (Nutt.) B.L. Rob. -- not accepted
  Liatris tenuifolia var. quadriflora Chapm. -- not accepted -- shortleaf blazing star
  Liatris tenuifolia var. tenuifolia Nutt. -- accepted -- shortleaf blazing star
  Liatris tenuis Shinners -- accepted -- Gulf blazing star, Gulf gayfeather
  Liatris turgida Gaiser -- not accepted -- turgid blazing star
  Liatris virgata Nutt. -- accepted -- wand blazing star, dense blazing star, grassleaf gayfeather
  Liatris X boykinii Torr. & A. Gray (pro sp.) -- accepted -- Boykin's gayfeather
  Liatris X deamii (Lunell) Shinners -- accepted
  Liatris X fallacior (Lunell) Rydb. (pro sp.) -- accepted -- gayfeather
  Liatris X freemaniana J. Allison -- accepted
  Liatris X frostii Gaiser -- accepted -- Frost's gayfeather
  Liatris X gladewitzii (Farw.) Farw. ex Shinners -- accepted -- Gladewitz's gayfeather
  Liatris X macdanieliana J. Allison -- accepted
  Liatris X nieuwlandii (Lunell) Gaiser -- not accepted
  Liatris X ridgwayi Standl. -- accepted -- Ridgeway's gayfeather
  Liatris X spheroidea Michx. (pro sp.) -- accepted -- spherical blazing star
  Liatris X steelei Gaiser -- accepted -- Steele's gayfeather
  Liatris X weaveri Shinners -- accepted -- Weaver's gayfeather
  Lidbeckia bipinnata Thunb. -- not accepted
  Ligularia Cass. -- accepted
  Ligularia amplectens (A. Gray) W.A. Weber -- not accepted
  Ligularia amplectens var. holmii (Greene) Dorn -- not accepted
  Ligularia bigelovii (A. Gray) W.A. Weber -- not accepted
  Ligularia bigelovii var. hallii (A. Gray) W.A. Weber -- not accepted
  Ligularia clivorum Maxim. -- not accepted
  Ligularia dentata (A. Gray) H. Hara -- accepted -- summer ragwort
  Ligularia holmii (Greene) W.A. Weber -- not accepted
  Ligularia porteri (Greene) W.A. Weber -- not accepted
  Ligularia pudica (Greene) W.A. Weber -- not accepted
  Ligularia soldanella (A. Gray) W.A. Weber -- not accepted
  Ligularia taraxacoides (A. Gray) W.A. Weber -- not accepted
  Ligularia websteri (Greenm.) W.A. Weber -- not accepted
  Lindheimera A. Gray & Engelm. -- accepted -- lindheimera
  Lindheimera texana A. Gray & Engelm. -- accepted -- Texas yellowstar, Texas star
  Linosyris arborescens A. Gray -- not accepted
  Linosyris carnosa A. Gray -- not accepted
  Linosyris texana Torr. & A. Gray -- not accepted
  Lipochaeta DC. -- accepted -- nehe
  Lipochaeta acris Sherff -- not accepted
  Lipochaeta alata Sherff -- not accepted
  Lipochaeta alata var. acrior Sherff -- not accepted
  Lipochaeta alata var. pulchrior Sherff -- not accepted
  Lipochaeta bryanii Sherff -- not accepted -- pili nehe
  Lipochaeta calycosa A. Gray -- not accepted
  Lipochaeta christophersenii H. St. John -- not accepted
  Lipochaeta connata (Gaudich.) DC. -- accepted -- nehe
  Lipochaeta connata var. acris (Sherff) R.C. Gardner -- accepted -- nehe
  Lipochaeta connata var. connata (Gaudich.) DC. -- accepted -- nehe
  Lipochaeta connata var. decurrens A. Gray -- not accepted
  Lipochaeta connata var. lata H. St. John -- not accepted
  Lipochaeta connata var. littoralis Hillebr. -- not accepted
  Lipochaeta degeneri Sherff -- accepted -- Molokai nehe
  Lipochaeta deltoidea H. St. John -- not accepted
  Lipochaeta dubia O. Deg. & Sherff -- not accepted
  Lipochaeta elliptica H. St. John -- not accepted
  Lipochaeta exigua O. Deg. & Sherff -- not accepted
  Lipochaeta fauriei Levl. -- not accepted -- nehe, Olokele Canyon nehe
  Lipochaeta flexuosa del Castillo -- not accepted
  Lipochaeta forbesii Sherff -- not accepted
  Lipochaeta forbesii var. sherffii O. Deg. & Clay -- not accepted
  Lipochaeta garberi H. St. John -- not accepted
  Lipochaeta hastata Hillebr. -- not accepted
  Lipochaeta heterophylla A. Gray -- accepted -- lavaflow nehe
  Lipochaeta heterophylla var. malvacea O. Deg. & Sherff -- not accepted
  Lipochaeta heterophylla var. molokaiensis Sherff -- not accepted
  Lipochaeta integrifolia (Nutt.) A. Gray -- not accepted -- Kure Atoll nehe
  Lipochaeta integrifolia var. argentea Sherff -- not accepted
  Lipochaeta integrifolia var. gracilis Sherff -- not accepted
  Lipochaeta integrifolia var. major Sherff -- not accepted
  Lipochaeta integrifolia var. megacephala O. Deg. & Sherff -- not accepted
  Lipochaeta intermedia O. Deg. & Sherff -- not accepted
  Lipochaeta kaenaensis H. St. John -- not accepted
  Lipochaeta kahoolawensis Sherff -- not accepted
  Lipochaeta kamolensis O. Deg. & Sherff -- not accepted -- nehe, Maui nehe
  Lipochaeta kawaihoaensis H. St. John -- not accepted
  Lipochaeta lanceolata Nutt. -- not accepted
  Lipochaeta lavarum (Gaudich.) DC. -- not accepted -- coastal nehe
  Lipochaeta lavarum var. conferta Sherff -- not accepted
  Lipochaeta lavarum var. hillebrandiana Sherff -- not accepted
  Lipochaeta lavarum var. lanaiensis Sherff -- not accepted
  Lipochaeta lavarum var. longifolia Sherff -- not accepted
  Lipochaeta lavarum var. maneleana Sherff -- not accepted
  Lipochaeta lavarum var. ovata Sherff -- not accepted
  Lipochaeta lavarum var. salicifolia Sherff -- not accepted
  Lipochaeta lavarum var. scaposa H. St. John -- not accepted
  Lipochaeta lavarum var. skottsbergii Sherff -- not accepted
  Lipochaeta lavarum var. stearnsii O. Deg. & Sherff -- not accepted
  Lipochaeta lobata (Gaudich.) DC. -- accepted -- shrubland nehe
  Lipochaeta lobata var. albescens Sherff -- not accepted
  Lipochaeta lobata var. aprevalliana (del Castillo) Sherff -- not accepted
  Lipochaeta lobata var. denticulata (Wawra) Sherff -- not accepted
  Lipochaeta lobata var. grossedentata O. Deg. & Sherff -- not accepted
  Lipochaeta lobata var. hastulata (Hook. & Arn.) Sherff -- not accepted
  Lipochaeta lobata var. hastulatoides O. Deg. & Sherff -- not accepted
  Lipochaeta lobata var. hosakae H. St. John -- not accepted
  Lipochaeta lobata var. incisior H. St. John -- not accepted
  Lipochaeta lobata var. leptophylla O. Deg. & Sherff -- accepted -- shrubland nehe, nehe
  Lipochaeta lobata var. lobata (Gaudich.) DC. -- accepted -- shrubland nehe
  Lipochaeta lobata var. makenensis O. Deg. & Sherff -- not accepted
  Lipochaeta lobata var. maunaloensis Sherff -- not accepted
  Lipochaeta mauiensis H. St. John -- not accepted
  Lipochaeta micrantha (Nutt.) A. Gray -- not accepted -- nehe, Kauai nehe
  Lipochaeta micrantha var. exigua (O. Deg. & Sherff) R.C. Gardner -- not accepted -- Kauai nehe
  Lipochaeta micrantha var. micrantha (Nutt.) A. Gray -- not accepted -- Kauai nehe
  Lipochaeta minuscula O. Deg. & Sherff -- not accepted
  Lipochaeta molokiniensis H. St. John -- not accepted
  Lipochaeta nesophila H. St. John -- not accepted
  Lipochaeta niihauensis H. St. John -- not accepted
  Lipochaeta ovata R.C. Gardner -- not accepted -- Honolulu nehe
  Lipochaeta perdita Sherff -- not accepted -- ko`oko`olau
  Lipochaeta pinnatifida H. St. John -- not accepted
  Lipochaeta populifolia (Sherff) R.C. Gardner -- not accepted
  Lipochaeta porophila O. Deg. & I. Deg. -- not accepted
  Lipochaeta profusa Sherff -- not accepted
  Lipochaeta profusa var. robustior O. Deg. & Sherff -- not accepted
  Lipochaeta remyi A. Gray -- not accepted -- annual nehe
  Lipochaeta robusta H. St. John -- not accepted
  Lipochaeta rockii Sherff -- accepted -- Rock's nehe
  Lipochaeta rockii var. dissecta Sherff -- not accepted
  Lipochaeta rockii var. parva H. St. John -- not accepted
  Lipochaeta rockii var. subovata Sherff -- not accepted
  Lipochaeta scabra H. St. John -- not accepted
  Lipochaeta setosa H. St. John -- not accepted
  Lipochaeta subcordata A. Gray -- not accepted -- grassland nehe
  Lipochaeta subcordata var. membranacea Sherff -- not accepted
  Lipochaeta subcordata var. populifolia Sherff -- not accepted
  Lipochaeta succulenta (Hook. & Arn.) DC. -- accepted -- seaside nehe
  Lipochaeta succulenta var. angustata Sherff -- not accepted
  Lipochaeta succulenta var. barclayi Sherff -- not accepted
  Lipochaeta succulenta var. decurrens (A. Gray) Sherff -- not accepted
  Lipochaeta succulenta var. trifida Sherff -- not accepted
  Lipochaeta tenuifolia A. Gray -- not accepted -- nehe, Waianae Range nehe
  Lipochaeta tenuis O. Deg. & Sherff -- not accepted -- streambed nehe
  Lipochaeta tenuis var. sellingii O. Deg. & Sherff -- not accepted
  Lipochaeta trilobata H. St. John -- not accepted
  Lipochaeta variolosa Levl. -- not accepted
  Lipochaeta venosa Sherff -- not accepted -- spreading nehe
  Lipochaeta vittata H. St. John -- not accepted
  Lipochaeta waimeaensis H. St. John -- not accepted -- nehe, Waimea Canyon nehe
  Lipochaeta warshauerii H. St. John -- not accepted
  Lipochaeta X procumbens O. Deg. & Sherff -- accepted -- nehe
  Litrisa Small -- not accepted
  Litrisa carnosa Small -- not accepted
  Logfia Cass. -- accepted -- cottonrose
  Logfia arizonica (A. Gray) Holub -- accepted -- Arizona cottonrose
  Logfia arvensis (L.) Holub -- accepted -- field cottonrose
  Logfia californica (Nutt.) Holub -- not accepted
  Logfia depressa (A. Gray) Holub -- accepted -- dwarf cottonrose
  Logfia filaginoides (Hook. & Arn.) Morefield -- accepted -- California cottonrose
  Logfia gallica (L.) Coss. & Germ. -- accepted -- narrowleaf cottonrose
  Logfia minima (Sm.) Dumort. -- accepted -- little cottonrose
  Lorandersonia Urbatsch, R.P. Roberts & Neubig -- accepted
  Lorandersonia baileyi (Wooton & Standl.) Urbatsch, R.P. Roberts & Neubig -- accepted -- Bailey's rabbitbrush
  Lorandersonia linifolia (Greene) Urbatsch, R.P. Roberts & Neubig -- accepted -- spearleaf rabbitbrush
  Lorandersonia microcephala (Cronquist) Urbatsch, R.P. Roberts & Neubig -- accepted
  Lorandersonia peirsonii (D.D. Keck) Urbatsch, R.P. Roberts & Neubig -- accepted -- Peirson's serpentweed
  Lorandersonia pulchella (A. Gray) Urbatsch, R.P. Roberts & Neubig -- accepted -- southwestern rabbitbrush
  Lorandersonia salicina (S.F. Blake) Urbatsch, R.P. Roberts & Neubig -- accepted -- willow glowweed
  Lorandersonia spathulata (L.C. Anderson) Urbatsch, R.P. Roberts & Neubig -- accepted -- Guadalupe rabbitbrush
  Lowellia aurea A. Gray -- not accepted
  Luina Benth. -- accepted -- silverback
  Luina hypoleuca Benth. -- accepted -- littleleaf silverback
  Luina nardosmia (A. Gray) Cronquist -- not accepted
  Luina nardosmia var. glabrata (Piper) Cronquist -- not accepted
  Luina serpentina Cronquist -- accepted -- creeping silverback
  Luina stricta (Greene) B.L. Rob. -- not accepted
  Luteidiscus calcisabulorus H. St. John -- not accepted
  Luteidiscus capillaris (Gaudich.) H. St. John -- not accepted
  Luteidiscus rockii (Sherff) H. St. John -- not accepted
  Lygodesmia D. Don -- accepted -- skeletonplant, skeleton plant, skeletonweed
  Lygodesmia aphylla (Nutt.) DC. -- accepted -- rose rush
  Lygodesmia aphylla var. texana Torr. & A. Gray -- not accepted
  Lygodesmia arizonica S. Tomb -- not accepted -- Arizona skeletonplant
  Lygodesmia bigelovii (A. Gray) Shinners -- not accepted
  Lygodesmia dianthopsis (Eaton ex King) S. Tomb -- not accepted -- Antelope Island skeletonplant, Antelope Island skeletonweed
  Lygodesmia doloresensis S. Tomb -- not accepted -- Dolores River skeletonplant
  Lygodesmia entrada S.L. Welsh & Goodrich -- not accepted -- rushpink skeletonplant
  Lygodesmia exigua (A. Gray) A. Gray -- not accepted
  Lygodesmia grandiflora (Nutt.) Torr. & A. Gray -- accepted -- largeflower skeletonplant, largeflower skeletonweed, rush-pink
  Lygodesmia grandiflora var. arizonica (S. Tomb) S.L. Welsh -- accepted -- Arizona skeletonplant
  Lygodesmia grandiflora var. dianthopsis (Eaton ex King) S.L. Welsh -- accepted -- Antelope Island skeletonplant
  Lygodesmia grandiflora var. doloresensis (S. Tomb) S.L. Welsh -- accepted -- Dolores River skeletonplant
  Lygodesmia grandiflora var. entrada (S.L. Welsh & Goodrich) S.L. Welsh -- accepted -- rushpink skeletonplant
  Lygodesmia grandiflora var. grandiflora (Nutt.) Torr. & A. Gray -- accepted
  Lygodesmia grandiflora var. stricta Maguire -- not accepted
  Lygodesmia juncea (Pursh) D. Don ex Hook. -- accepted -- rush skeletonplant, rush skeleton-plant, rush skeletonweed, skeletonweed, skeletonplant
  Lygodesmia pauciflora (Torr.) Shinners -- not accepted
  Lygodesmia ramosissima Greenm. -- accepted -- Pecos River skeletonplant
  Lygodesmia rostrata (A. Gray) A. Gray -- not accepted
  Lygodesmia spinosa Nutt. -- not accepted
  Lygodesmia tenuifolia (Raf.) Shinners -- not accepted
  Lygodesmia texana (Torr. & A. Gray) Greene -- accepted -- Texas skeletonplant
  Lygodesmia thurberi (A. Gray) Shinners -- not accepted
  Lygodesmia wrightii (A. Gray) Shinners -- not accepted
  Macdougalia bigelovii (A. Gray) A. Heller -- not accepted
  Machaeranthera Nees -- accepted -- tansyaster, goldenweed, machaeranthera
  Machaeranthera ammophila Reveal -- not accepted
  Machaeranthera amplifolia Woot. & Standl. -- not accepted
  Machaeranthera angustifolia Rydb. non Woot. & Standl. -- not accepted
  Machaeranthera angustifolia Woot. & Standl. -- not accepted
  Machaeranthera annua (Rydb.) Shinners -- not accepted -- viscid tansyaster
  Machaeranthera aquifolia Greene ex Woot. & Standl. -- not accepted
  Machaeranthera arida B.L. Turner & Horne -- not accepted -- arid tansyaster, arid machaeranthera
  Machaeranthera arizonica R.C. Jacks. & R.R. Johnson -- not accepted
  Machaeranthera asteroides (Torr.) Greene -- not accepted
  Machaeranthera asteroides var. asteroides (Torr.) Greene -- not accepted -- New Mexico tansyaster
  Machaeranthera asteroides var. glandulosa B.L. Turner -- not accepted
  Machaeranthera asteroides var. lagunensis (D.D. Keck) B.L. Turner -- not accepted
  Machaeranthera attenuata Howell -- not accepted
  Machaeranthera aurea (A. Gray) Shinners -- not accepted -- Houston tansyaster
  Machaeranthera australis (Greene) Shinners -- not accepted
  Machaeranthera bigelovii (A. Gray) Greene -- not accepted -- Bigelow's tansy-aster, Bigelow's tansyaster, Bigelow's machaeranthera
  Machaeranthera bigelovii var. bigelovii (A. Gray) Greene -- not accepted -- Bigelow tansyaster, Bigelow's tansyaster
  Machaeranthera bigelovii var. commixta (Greene) B.L. Turner -- not accepted -- Bigelow's tansyaster
  Machaeranthera bigelovii var. mucronata (Greene) B.L. Turner -- not accepted -- Bigelow tansyaster, Bigelow's tansyaster
  Machaeranthera blephariphylla (A. Gray) Shinners -- not accepted -- Texas tansyaster
  Machaeranthera boltoniae (Greene) B.L. Turner & Horne -- not accepted
  Machaeranthera brevilingulata (Sch. Bip. ex Hemsl.) B.L. Turner & Horne -- not accepted
  Machaeranthera canescens (Pursh) A. Gray -- not accepted -- hoary aster, hoary goldenweed, hoary tansy-aster, purple aster, hoary tansyaster, hoary machaeranthera
  Machaeranthera canescens ssp. canescens (Pursh) A. Gray -- not accepted -- ironplant goldenweed, hoary tansy-aster, hoary tansyaster
  Machaeranthera canescens ssp. canescens var. ambigua B.L. Turner -- not accepted -- hoary aster, hoary tansyaster
  Machaeranthera canescens ssp. canescens var. canescens (Pursh) A. Gray -- not accepted -- hoary tansy-aster, ironplant goldenweed, spiny goldenweed, hoary tansyaster, cutleaf goldenweed
  Machaeranthera canescens ssp. canescens var. incana (Lindl.) A. Gray -- not accepted -- cutleaf goldenweed, hoary tansyaster, cutleaf machaeranthera
  Machaeranthera canescens ssp. canescens var. leucanthemifolia (Greene) Welsh -- not accepted -- whiteflower tansyaster, whiteflower machaeranthera
  Machaeranthera canescens ssp. canescens var. sessiliflora (Nutt.) B.L. Turner -- not accepted -- hoary tansyaster
  Machaeranthera canescens ssp. canescens var. shastensis (A. Gray) B.L. Turner -- not accepted -- Shasta tansyaster, Shasta machaeranthera
  Machaeranthera canescens ssp. canescens var. ziegleri (Munz) B.L. Turner -- not accepted -- Ziegler's tansyaster
  Machaeranthera canescens ssp. glabra (A. Gray) B.L. Turner -- not accepted -- hoary tansyaster
  Machaeranthera canescens ssp. glabra var. aristata (Eastw.) B.L. Turner -- not accepted -- hoary tansyaster
  Machaeranthera canescens ssp. glabra var. glabra A. Gray -- not accepted -- hoary tansyaster
  Machaeranthera canescens ssp. glabra var. nebraskana B.L. Turner -- not accepted -- Nebraska tansyaster
  Machaeranthera canescens ssp. ziegleri Munz -- not accepted
  Machaeranthera canescens var. ambigua B.L. Turner -- not accepted -- hoary tansyaster
  Machaeranthera canescens var. aristata (Eastw.) B.L. Turner -- not accepted -- hoary tansyaster
  Machaeranthera canescens var. commixta (Greene) S.L. Welsh -- not accepted
  Machaeranthera canescens var. glabra A. Gray -- not accepted -- hoary tansyaster
  Machaeranthera canescens var. incana (Lindl.) Gray -- not accepted -- hoary tansyaster
  Machaeranthera canescens var. latifolia (A. Nelson) S.L. Welsh, non A. Gray -- not accepted
  Machaeranthera canescens var. latifolia A. Gray -- not accepted
  Machaeranthera canescens var. leucanthemifolia (Greene) Welsh -- not accepted -- whiteflower tansyaster
  Machaeranthera canescens var. monticola Dorn -- not accepted
  Machaeranthera canescens var. nebraskana B.L. Turner -- not accepted -- Nebraska tansyaster
  Machaeranthera canescens var. sessiliflora (Nutt.) B.L. Turner -- not accepted -- hoary tansyaster
  Machaeranthera canescens var. shastensis (A. Gray) B.L. Turner -- not accepted -- Shasta tansyaster
  Machaeranthera canescens var. tephrodes A. Gray -- not accepted
  Machaeranthera canescens var. vacans (A. Nelson) S.L. Welsh -- not accepted
  Machaeranthera canescens var. viridis A. Gray -- not accepted
  Machaeranthera canescens var. viscosa (Nutt.) Piper -- not accepted
  Machaeranthera canescens var. ziegleri (Munz) B.L. Turner -- not accepted -- Ziegler's tansyaster
  Machaeranthera carnosa (A. Gray) G.L. Nesom -- not accepted -- shrubby alkali tansyaster, shrubby alkaliaster, shrubby alkali aster
  Machaeranthera carnosa var. carnosa (A. Gray) G.L. Nesom -- not accepted -- shrubby alkaliaster
  Machaeranthera carnosa var. intricata (A. Gray) G.L. Nesom -- not accepted -- shrubby alkaliaster
  Machaeranthera centaureoides Greene ex Woot. & Standl. -- not accepted
  Machaeranthera cichoriacea Greene -- not accepted
  Machaeranthera cognata (H.M. Hall) Cronquist & D.D. Keck -- not accepted
  Machaeranthera coloradoensis (A. Gray) Osterh. -- not accepted -- Colorado tansyaster
  Machaeranthera coloradoensis var. brandegeei (Rydb.) T.J. Watson ex R.L. Hartm. -- not accepted -- Brandegee's tansyaster
  Machaeranthera coloradoensis var. coloradoensis (A. Gray) Osterh. -- not accepted -- Colorado tansyaster
  Machaeranthera commixta Greene -- not accepted
  Machaeranthera confertifolia (Cronquist) Cronquist -- not accepted
  Machaeranthera coronopifolia (Nutt.) A. Nelson -- not accepted
  Machaeranthera correllii Shinners -- not accepted
  Machaeranthera coulteri (Gray) B.L. Turner & Horne -- not accepted -- Silver Lake daisy
  Machaeranthera coulteri var. arida (B.L. Turner & Horne) B.L. Turner -- not accepted
  Machaeranthera cronquistii (S.L. Welsh & N.D. Atwood) Cronquist -- not accepted
  Machaeranthera divaricata (Nutt.) Greene -- not accepted
  Machaeranthera eradiata (A. Gray) Howell -- not accepted
  Machaeranthera fremontii Rydb. -- not accepted
  Machaeranthera glabella Greene ex Rydb. -- not accepted
  Machaeranthera glabriuscula (Nutt.) Cronquist & D.D. Keck -- not accepted
  Machaeranthera glabriuscula var. confertifolia Cronquist -- not accepted
  Machaeranthera glabriuscula var. villosa (Nutt.) Cronquist & D.D. Keck -- not accepted
  Machaeranthera gracilis (Nutt.) Shinners -- not accepted -- slender goldenweed
  Machaeranthera grindelioides (Nutt.) Shinners -- not accepted -- rayless tansy-aster, rayless tansyaster, rayless aster
  Machaeranthera grindelioides var. depressa (Maguire) Cronquist & D.D. Keck -- not accepted -- rayless aster, rayless tansyaster
  Machaeranthera grindelioides var. grindelioides (Nutt.) Shinners -- not accepted -- rayless tansy-aster, rayless aster, rayless tansyaster
  Machaeranthera gymnocephala auct. non (DC.) Shinners -- not accepted
  Machaeranthera gypsitherma G.L. Nesom, Vorobik & R.L. Hartm. -- accepted -- La Playa Springs tansyaster
  Machaeranthera gypsophila B.L. Turner -- not accepted -- gypsum tansyaster
  Machaeranthera hansonii A. Nelson -- not accepted
  Machaeranthera havardii (Waterf.) Shinners -- not accepted
  Machaeranthera heterocarpa R.L. Hartm. & M.A. Lane -- not accepted
  Machaeranthera hiemalis A. Nelson -- not accepted
  Machaeranthera incana (Lindl.) Greene -- not accepted
  Machaeranthera inops A. Nelson & J.F. Macbr. -- not accepted
  Machaeranthera inops var. atrata A. Nelson & J.F. Macbr. -- not accepted
  Machaeranthera inornata (Greene) Greene -- not accepted
  Machaeranthera juncea (Greene) Shinners -- not accepted -- rush tansy-aster, rush bristleweed
  Machaeranthera kingii (D.C. Eaton) Cronquist & D.D. Keck -- not accepted
  Machaeranthera kingii var. barnebyana S.L. Welsh & Goodrich -- not accepted
  Machaeranthera laetevirens Greene non Aster laetevirens (Greene) Greene -- not accepted
  Machaeranthera laevis (Woot. & Standl.) Shinners -- not accepted
  Machaeranthera lagunensis D.D. Keck -- not accepted
  Machaeranthera latifolia A. Nelson -- not accepted
  Machaeranthera leptophylla Rydb. -- not accepted
  Machaeranthera leucanthemifolia (Greene) Greene -- not accepted
  Machaeranthera linearifolia (T.J. Watson) Cronquist -- not accepted
  Machaeranthera linearis Rydb. non Greene -- not accepted
  Machaeranthera linearis Greene -- not accepted
  Machaeranthera magna A. Nelson -- not accepted
  Machaeranthera mexicana B.L. Turner & Horne -- not accepted
  Machaeranthera montana Greene -- not accepted
  Machaeranthera mucronata Greene -- not accepted
  Machaeranthera orcuttii (Vasey & Rose) Cronquist & D.D. Keck -- not accepted
  Machaeranthera oxylepis Greene -- not accepted
  Machaeranthera paniculata A. Nelson -- not accepted
  Machaeranthera parthenium Greene -- not accepted
  Machaeranthera parviflora A. Gray -- not accepted -- small-flower tansy-aster, smallflower tansyaster
  Machaeranthera pattersonii (A. Gray) Greene -- not accepted
  Machaeranthera phyllocephala (DC.) Shinners -- not accepted -- camphor daisy
  Machaeranthera phyllocephala var. annua (Rydb.) Shinners -- not accepted
  Machaeranthera phyllocephala var. megacephala (Nash) Shinners -- not accepted
  Machaeranthera pinnata (Nutt.) Shinners -- not accepted
  Machaeranthera pinnatifida (Hook.) Shinners -- not accepted -- lacy tansy-aster, spiny goldenweed, lacy tansyaster, cutleaf goldenweed, pinnate machaeranthera
  Machaeranthera pinnatifida ssp. gooddingii (A. Nelson) B.L. Turner & R.L. Hartm. -- not accepted -- Goodding's tansyaster, Goodding's aster
  Machaeranthera pinnatifida ssp. gooddingii var. paradoxa B.L. Turner & R.L. Hartm. -- not accepted -- Goodding's aster, Goodding's tansyaster
  Machaeranthera pinnatifida ssp. pinnatifida (Hook.) Shinners -- not accepted -- lacy tansy-aster, lacy tansyaster
  Machaeranthera pinnatifida ssp. pinnatifida var. chihuahuana B.L. Turner & R.L. Hartm. -- not accepted -- machaeranthera, Chihuahua tansyaster, Chihuahua aster
  Machaeranthera pinnatifida ssp. pinnatifida var. glaberrima (Rydb.) B.L. Turner & R.L. Hartm. -- not accepted -- lacy tansyaster
  Machaeranthera pinnatifida ssp. pinnatifida var. pinnatifida (Hook.) Shinners -- not accepted -- lacy tansy-aster, spiny goldenweed, lacy tansyaster
  Machaeranthera pinnatifida var. chihuahuana B.L. Turner & R.L. Hartm. -- not accepted -- Chihuahua tansyaster
  Machaeranthera pinnatifida var. glaberrima (Rydb.) B.L. Turner & R.L. Hartm. -- not accepted -- lacy tansyaster
  Machaeranthera pinnatifida var. gooddingii (A. Nelson) B.L. Turner & R.L. Hartm. -- not accepted -- Goodding's tansyaster
  Machaeranthera pinnatifida var. paradoxa B.L. Turner & R.L. Hartm. -- not accepted -- Goodding's tansyaster
  Machaeranthera pinnatifida var. pinnatifida (Hook.) Shinners -- not accepted -- lacy tansyaster
  Machaeranthera pinnatifida var. scabrella (Greene) B.L. Turner & R.L. Hartm. -- not accepted -- machaeranthera
  Machaeranthera pinosa Elmer -- not accepted
  Machaeranthera pruinosa A. Gray -- not accepted
  Machaeranthera pulverulenta (Nutt.) Greene -- not accepted
  Machaeranthera pulverulenta var. vacans A. Nelson -- not accepted
  Machaeranthera pygmaea (A. Gray) Woot. & Standl. -- not accepted
  Machaeranthera ramosa A. Nelson -- not accepted
  Machaeranthera rigida Greene -- not accepted
  Machaeranthera riparia (Kunth) A.G. Jones -- not accepted -- alkali aster, Chiricahua Mountain tansyaster
  Machaeranthera rubricaulis Rydb. -- not accepted
  Machaeranthera scabrella (Greene) Shinners -- not accepted
  Machaeranthera scoparia Greene -- not accepted
  Machaeranthera selbyi Rydb. -- not accepted
  Machaeranthera sessiliflora (Nutt.) Greene -- not accepted
  Machaeranthera shastensis A. Gray -- not accepted
  Machaeranthera shastensis var. eradiata (A. Gray) Cronquist & D.D. Keck -- not accepted
  Machaeranthera shastensis var. glossophylla (Piper) Cronquist & D.D. Keck -- not accepted
  Machaeranthera shastensis var. latifolia (Cronquist) Cronquist & D.D. Keck -- not accepted
  Machaeranthera shastensis var. montana (Greene) Cronquist & D.D. Keck -- not accepted
  Machaeranthera simplex Woot. & Standl. -- not accepted
  Machaeranthera sonorae (A. Gray) J. Stucky -- not accepted
  Machaeranthera spinulosa (Greene) Cory non Amellus spinulosa Pursh -- not accepted
  Machaeranthera subalpina Greene -- not accepted
  Machaeranthera superba A. Nelson -- not accepted
  Machaeranthera tagetina Greene -- accepted -- mesa tansyaster, mesa tansy-aster
  Machaeranthera tanacetifolia (Kunth) Nees -- accepted -- tanseyleaf tansyaster, Takhoka-daisy, tanseyleaf aster, tanseyleaf goldenweed
  Machaeranthera tenuis (S. Watson) B.L. Turner & Horne -- not accepted
  Machaeranthera tephrodes (A. Gray) Greene -- not accepted
  Machaeranthera texensis (R.C. Jacks.) Shinners -- not accepted
  Machaeranthera tortifolia (Torr. & A. Gray) Cronquist & D.D. Keck -- not accepted
  Machaeranthera tortifolia var. imberbis Cronquist -- not accepted
  Machaeranthera venusta (M.E. Jones) Cronquist & D.D. Keck -- not accepted
  Machaeranthera verna A. Nelson -- not accepted
  Machaeranthera viscida (Woot. & Standl.) R.L. Hartm. -- not accepted -- sticky tansyaster
  Machaeranthera viscosa (Nutt.) Greene -- not accepted
  Machaeranthera wrightii (A. Gray) Cronquist & D.D. Keck -- not accepted
  Macronema aberrans A. Nelson -- not accepted
  Macronema discoidea Nutt. -- not accepted
  Macronema greenei (A. Gray) Greene -- not accepted
  Macronema lineare Rydb. -- not accepted
  Macronema lineare var. canescens A. Nelson -- not accepted
  Macronema obovatum Rydb. non Haplopappus obovatus Phil. -- not accepted
  Macronema suffruticosum Nutt. -- not accepted
  Macronema watsonii (A. Gray) Greene -- not accepted
  Macrorhynchus glaucus var. laciniatus D.C. Eaton -- not accepted
  Macrorhynchus heterophyllus Nutt. -- not accepted
  Macrorhynchus retrorsus Benth. -- not accepted
  Madia Molina -- accepted -- tarweed
  Madia anomala Greene -- accepted -- plumpseeded madia
  Madia bolanderi (A. Gray) A. Gray -- not accepted -- Bolander's madia
  Madia capitata Nutt. -- not accepted
  Madia citrigracilis D.D. Keck -- accepted -- Shasta tarweed
  Madia citriodora Greene -- accepted -- lemonscented madia, lemonscent madia
  Madia dissitiflora (Nutt.) Torr. & A. Gray -- not accepted
  Madia doris-nilesiae T.W. Nelson & J.P. Nelson -- not accepted -- serpentine tarweed
  Madia elegans D. Don ex Lindl. -- accepted -- common madia, showy tarweed, spring madia
  Madia elegans ssp. densifolia (Greene) D.D. Keck -- not accepted -- showy tarweed
  Madia elegans ssp. elegans D. Don ex Lindl. -- not accepted -- common madia
  Madia elegans ssp. vernalis D.D. Keck -- not accepted -- spring madia
  Madia elegans ssp. wheeleri (A. Gray) D.D. Keck -- not accepted -- Wheeler's tarweed
  Madia elegans var. densifolia (Greene) Jeps. -- not accepted
  Madia exigua (Sm.) A. Gray -- accepted -- small tarweed
  Madia glomerata Hook. -- accepted -- mountain tarweed, mountain tarplant, cluster tarweed
  Madia gracilis (Sm.) D.D. Keck -- accepted -- grassy tarweed, slender tarweed
  Madia gracilis ssp. collina D.D. Keck -- not accepted
  Madia gracilis ssp. gracilis (Sm.) D.D. Keck -- not accepted -- grassy tarweed
  Madia gracilis ssp. pilosa D.D. Keck -- not accepted
  Madia hallii D.D. Keck -- not accepted -- Hall's madia
  Madia madioides (Nutt.) Greene -- not accepted -- woodland madia
  Madia minima (A. Gray) D.D. Keck -- not accepted -- oppositeleaved tarweed, least tarweed
  Madia nutans (Greene) D.D. Keck -- not accepted -- nodding madia
  Madia radiata Kellogg -- accepted -- golden madia
  Madia rammii Greene -- not accepted -- Ramm's madia
  Madia sativa Molina -- accepted -- coast tarweed, Chilean tarweed, tarweed
  Madia sativa ssp. capitata (Nutt.) Piper -- not accepted
  Madia sativa var. congesta Torr. & A. Gray -- not accepted
  Madia stebbinsii T.W. Nelson & J.P. Nelson -- not accepted -- Stebbins' tarweed
  Madia subspicata D.D. Keck -- accepted -- slender tarweed
  Madia yosemitana Parry ex A. Gray -- not accepted -- Yosemite tarweed
  Malacothrix DC. -- accepted -- desertdandelion, desert dandelion, malacothrix
  Malacothrix altissima Greene -- not accepted
  Malacothrix arachnoidea McGregor -- not accepted
  Malacothrix blairii (Munz & I.M. Johnst.) Munz & I.M. Johnst. -- not accepted
  Malacothrix californica DC. -- accepted -- California desertdandelion, California desert dandelion
  Malacothrix californica var. glabrata A. Gray ex D.C. Eaton -- not accepted
  Malacothrix clevelandii A. Gray -- accepted -- Cleveland's desertdandelion, Cleveland's desert dandelion
  Malacothrix clevelandii var. stebbinsii (W.S. Davis & P.H. Raven) Cronquist -- not accepted
  Malacothrix coulteri Harv. & A. Gray -- accepted -- snake's head, snake's-head, snakehead desert dandelion
  Malacothrix coulteri var. cognata Jeps. -- not accepted
  Malacothrix crispifolia W.S. Davis -- not accepted -- petite desertdandelion
  Malacothrix fendleri A. Gray -- accepted -- Fendler's desertdandelion, Fendler's desert dandelion
  Malacothrix floccifera (DC.) S.F. Blake -- accepted -- woolly desertdandelion, wooly desert dandelion
  Malacothrix foliosa A. Gray -- accepted -- leafy desertdandelion
  Malacothrix foliosa ssp. crispifolia W.S. Davis -- accepted -- petite desertdandelion
  Malacothrix foliosa ssp. foliosa A. Gray -- accepted -- leafy desertdandelion
  Malacothrix foliosa ssp. philbrickii W.S. Davis -- accepted -- Philbrick's desertdandelion
  Malacothrix foliosa ssp. polycephala W.S. Davis -- accepted -- manyhead desertdandelion
  Malacothrix foliosa var. indecora (Greene) E.W. Williams -- not accepted
  Malacothrix foliosa var. squalida (Greene) E.W. Williams -- not accepted
  Malacothrix glabrata (A. Gray ex D.C. Eaton) A. Gray -- accepted -- smooth desertdandelion, smooth desert dandelion
  Malacothrix implicata Eastw. -- not accepted
  Malacothrix incana (Nutt.) Torr. & A. Gray -- accepted -- dunedelion
  Malacothrix incana var. succulenta (Elmer) E.W. Williams -- not accepted
  Malacothrix indecora Greene -- accepted -- Santa Cruz Island desertdandelion, Santa Cruz Island malocothrix
  Malacothrix insularis Greene -- accepted -- island desertdandelion
  Malacothrix insularis var. squalida (Greene) Ferris -- not accepted
  Malacothrix intermedia W.S. Davis -- not accepted -- intermediate desertdandelion
  Malacothrix junakii W.S. Davis -- accepted -- Junak's desertdandelion, intermediate desertdandelion
  Malacothrix obtusa Benth. -- not accepted
  Malacothrix parviflora Benth. -- not accepted
  Malacothrix phaeocarpa W.S. Davis -- accepted -- Davis' desertdandelion
  Malacothrix platyphylla A. Gray -- not accepted
  Malacothrix polycephala W.S. Davis -- not accepted -- manyhead desertdandelion
  Malacothrix saxatilis (Nutt.) Torr. & A. Gray -- accepted -- cliff desertdandelion, cliff desert dandelion
  Malacothrix saxatilis var. altissima (Greene) Ferris -- not accepted
  Malacothrix saxatilis var. arachnoidea (McGregor) E.W. Williams -- accepted -- cliff desertdandelion
  Malacothrix saxatilis var. commutata (Torr. & A. Gray) Ferris -- accepted -- cliff desertdandelion
  Malacothrix saxatilis var. implicata (Eastw.) H.M. Hall -- accepted -- cliff desertdandelion
  Malacothrix saxatilis var. saxatilis (Nutt.) Torr. & A. Gray -- accepted -- cliff desertdandelion
  Malacothrix saxatilis var. tenuifolia (Nutt.) A. Gray -- accepted -- cliff desertdandelion, cliff desert dandelion
  Malacothrix saxatilis var. tenuissima Munz -- not accepted
  Malacothrix senecioides Reiche -- not accepted
  Malacothrix similis W.S. Davis & P.H. Raven -- accepted -- twin desertdandelion
  Malacothrix sonchoides (Nutt.) Torr. & A. Gray -- accepted -- sowthistle desertdandelion, yellow-saucers, sowthistle desert dandelion
  Malacothrix sonchoides var. torreyi (A. Gray) E.W. Williams -- not accepted
  Malacothrix sonorae W.S. Davis & P.H. Raven -- accepted -- Sonoran desertdandelion, Sonoran desert dandelion
  Malacothrix squalida Greene -- accepted -- Santa Cruz desertdandelion, island malacothrix
  Malacothrix stebbinsii W.S. Davis & P.H. Raven -- accepted -- Stebbins' desertdandelion, Stebbins' desert dandelion
  Malacothrix succulenta Elmer -- not accepted
  Malacothrix tenuifolia (Nutt.) Torr. & A. Gray -- not accepted
  Malacothrix torreyi A. Gray -- accepted -- Torrey's desertdandelion, Mohave aster, Torrey's desert dandelion
  Malacothrix xanthii A. Gray -- accepted
  Malperia S. Watson -- accepted -- malperia
  Malperia tenuis S. Watson -- accepted -- brownturbans
  Mantisalca Cass. -- accepted -- mantisalca
  Mantisalca salmantica (L.) Briq. & Cavillier -- accepted -- dagger flower, dagger-flower
  Mariana mariana (L.) Hill -- not accepted
  Marshallia Schreb. -- accepted -- Barbara's buttons, marshallia
  Marshallia caespitosa Nutt. ex DC. -- accepted -- puffballs, seep marshallia
  Marshallia caespitosa var. caespitosa Nutt. ex DC. -- not accepted -- puffballs
  Marshallia caespitosa var. signata Beadle & F.E. Boynt. -- not accepted -- puffballs
  Marshallia graminifolia (Walter) Small -- accepted -- grassleaf Barbara's buttons
  Marshallia graminifolia ssp. tenuifolia (Raf.) L. Watson -- not accepted
  Marshallia graminifolia var. cynanthera (Elliot) Beadle & F.E. Boynt. -- not accepted -- grassleaf Barbara's buttons
  Marshallia graminifolia var. graminifolia (Walter) Small -- not accepted -- grassleaf Barbara's buttons
  Marshallia graminifolia var. tenuifolia (Raf.) L. Watson -- not accepted -- grassleaf Barbara's buttons
  Marshallia grandiflora Beadle & F.E. Boynt. -- accepted -- Monongahela Barbara's buttons
  Marshallia laciniarioides Small -- not accepted
  Marshallia mohrii Beadle & F.E. Boynt. -- accepted -- Mohr's Barbara's-buttons, Mohr's Barbara's buttons
  Marshallia obovata (Walter) Beadle & F.E. Boynt. -- accepted -- spoonshape Barbara's buttons
  Marshallia obovata var. obovata (Walter) Beadle & F.E. Boynt. -- not accepted -- spoonshape Barbara's buttons
  Marshallia obovata var. platyphylla (M.A. Curtis) Beadle & F.E. Boynt. -- not accepted
  Marshallia obovata var. scaposa Channell -- not accepted -- spoonshape Barbara's buttons
  Marshallia ramosa Beadle & F.E. Boynt. -- accepted -- southern Barbara's buttons
  Marshallia tenuifolia Raf. -- not accepted
  Marshallia tenuifolia var. graminifolia (Walter) Gandhi & R.D. Thomas -- not accepted
  Marshallia trinervia (Walter) Trel. -- accepted -- broadleaf Barbara's buttons
  Marshallia williamsonii Small -- not accepted
  Maruta cotula (L) DC -- not accepted
  Matricaria L. -- accepted -- mayweed
  Matricaria ambigua (Ledeb.) Krylov -- not accepted
  Matricaria chamomilla L. 1755 & 1763 non 1753 -- not accepted
  Matricaria chamomilla L. -- accepted -- German chamomile, crown mayweed
  Matricaria chamomilla var. coronata (J. Gay) Coss. & Germ. -- not accepted
  Matricaria courrantiana DC. -- not accepted -- crown mayweed
  Matricaria discoidea DC. -- accepted -- disc mayweed, pineapple weed, pineappleweed
  Matricaria globifera (Thunb.) Fenzl ex Harv. -- not accepted
  Matricaria grandiflora (Hook.) Britton -- not accepted
  Matricaria hookeri (Sch. Bip.) Czern. -- not accepted
  Matricaria inodora L. -- not accepted
  Matricaria maritima L. -- not accepted
  Matricaria maritima ssp. inodora (L.) Clapham -- not accepted
  Matricaria maritima ssp. maritima L. -- not accepted -- false mayweed
  Matricaria maritima ssp. phaeocephala (Rupr.) Rauschert -- not accepted
  Matricaria maritima var. agrestis (Knaf) Wilmott -- not accepted
  Matricaria maritima var. nana (Hook.) B. Boivin -- not accepted
  Matricaria matricarioides auct. non (Less.) Porter -- not accepted -- disc mayweed, pineappleweed
  Matricaria occidentalis Greene -- accepted -- valley mayweed
  Matricaria parthenium L. -- not accepted
  Matricaria perforata Mérat -- not accepted -- German chamomile, scentless mayweed
  Matricaria prostrata Sw. -- not accepted
  Matricaria recutita L. -- not accepted -- mayweed, German chamomile
  Matricaria suaveolens (Pursh) Buchenau non L. -- not accepted
  Matricaria suaveolens L. -- not accepted
  Matricaria suffruticosa (L.) Druce -- not accepted -- shrubby mayweed
  Mauranthemum R.Vogt & Oberpr. -- accepted
  Mauranthemum paludosum (Poir.) Vogt & Oberprieler -- accepted
  Megalodonta Greene -- not accepted -- water-marigold, watermarigold
  Megalodonta beckii (Torr. ex Spreng.) Greene -- not accepted -- Beck's watermarigold
  Megalodonta beckii var. beckii (Torr. ex Spreng.) Greene -- not accepted -- Beck's watermarigold
  Megalodonta beckii var. hendersonii Sherff -- not accepted -- Henderson's watermarigold
  Megalodonta beckii var. oregonensis Sherff -- not accepted -- Oregon watermarigold
  Melampodium L. -- accepted -- blackfoot, melampodium
  Melampodium appendiculatum B.L. Rob. -- accepted
  Melampodium australe Loefl. -- not accepted
  Melampodium cinereum DC. -- accepted -- hoary blackfoot, rockdaisy
  Melampodium cinereum var. cinereum DC. -- not accepted -- hoary blackfoot
  Melampodium cinereum var. hirtellum Stuessy -- not accepted -- hoary blackfoot
  Melampodium cinereum var. ramosissimum (DC.) A. Gray -- not accepted -- hoary blackfoot
  Melampodium divaricatum (Rich.) DC. -- accepted -- boton de oro
  Melampodium hispidum Kunth -- not accepted
  Melampodium humile Sw. -- not accepted
  Melampodium leucanthum Torr. & A. Gray -- accepted -- plains blackfoot, plains blackfoot daisy
  Melampodium longicorne A. Gray -- accepted -- Arizona blackfoot
  Melampodium perfoliatum (Cav.) Kunth -- accepted -- perfoliate blackfoot
  Melampodium ruderale Sw. -- not accepted
  Melampodium sericeum Lag. -- accepted -- rough blackfoot
  Melampodium strigosum Stuessy -- accepted -- shaggy blackfoot
  Melanthera Rohr -- accepted -- squarestem
  Melanthera angustifolia A. Rich. -- accepted -- Everglades squarestem
  Melanthera aspera (Jacq.) Steud. ex Small -- not accepted -- yerba de cabra
  Melanthera aspera var. aspera (Jacq.) Steud. ex Small -- not accepted -- yerba de cabra
  Melanthera aspera var. glabriuscula (Kuntze) J.C. Parks -- not accepted -- yerba de cabra
  Melanthera biflora (L.) Wild. -- accepted -- Honolulu nehe
  Melanthera bryanii (Sherff) W.L. Wagner & H. Rob. -- accepted -- pili nehe
  Melanthera calcicola Britton -- not accepted
  Melanthera canescens (Kuntze) O.E. Schulz -- not accepted
  Melanthera carpenteri Small -- not accepted
  Melanthera confusa Britton -- not accepted
  Melanthera deltoidea Michx. -- not accepted
  Melanthera fauriei (H. Lév.) W.L. Wagner & H. Rob. -- accepted -- Olokele Canyon nehe
  Melanthera hastata Michx. -- not accepted
  Melanthera integrifolia (Nutt.) W.L. Wagner & H. Rob. -- accepted -- Kure Atoll nehe
  Melanthera kamolensis (O. Deg.) & Sherff) W.L. Wagner & H. Rob. -- accepted -- Maui nehe
  Melanthera lavarum (Gaudich.) W.L. Wagner & H. Rob. -- accepted -- coastal nehe
  Melanthera ligulata Small -- not accepted -- pineland squarestem
  Melanthera micrantha (Nutt.) W.L. Wagner & H. Rob. -- accepted
  Melanthera micrantha ssp. exigua (O. Deg. & Sherff) W.L. Wagner & H. Rob. -- accepted -- Kauai nehe
  Melanthera micrantha ssp. micrantha (Nutt.) W.L. Wagner & H. Rob. -- accepted -- Kauai nehe
  Melanthera montana O.E. Schulz -- not accepted
  Melanthera nivea (L.) Small -- accepted -- snow squarestem, yerba de cabra, pineland squarestem
  Melanthera parvifolia Small -- accepted -- small-leaf squarestem
  Melanthera perdita (Sherff) W.L. Wagner & H. Rob. -- accepted -- ko`oko`olau
  Melanthera populifolia (Sherff) W.L. Wagner & H. Rob. -- accepted -- grassland nehe
  Melanthera radiata Small -- not accepted
  Melanthera remyi (A. Gray) W.L. Wagner & H. Rob. -- accepted -- annual nehe
  Melanthera subcordata (A. Gray) W.L. Wagner & H. Rob. -- accepted
  Melanthera tenuifolia (A. Gray) W.L. Wagner & H. Rob. -- accepted -- Waianae Range nehe
  Melanthera tenuis (O. Deg. & Sherff) W.L. Wagner & H. Rob. -- accepted -- streambed nehe
  Melanthera venosa (Sherff) W.L. Wagner & H. Rob. -- accepted -- spreading nehe
  Melanthera waimeaensis (H. St. John) W.L. Wagner & H. Rob. -- accepted -- Waimea Canyon nehe
  Mesadenia atriplicifolia (L.) Raf. -- not accepted
  Mesadenia diversifolia (Torr. & A. Gray) Greene -- not accepted
  Mesadenia elliottii Harper -- not accepted
  Mesadenia floridana (A. Gray) Greene -- not accepted
  Mesadenia lanceolata (Nutt.) Raf. -- not accepted
  Mesadenia lanceolata var. virescens Harper -- not accepted
  Mesadenia maxima Harper -- not accepted
  Mesadenia reniformis (Hook.) Raf. -- not accepted
  Mesadenia sulcata (Fernald) Harper -- not accepted
  Mesadenia tuberosa (Nutt.) Britton -- not accepted
  Micropsis DC. -- accepted
  Micropsis dasycarpa (Griseb.) Beauverd -- accepted
  Micropus L. -- accepted -- cottonseed
  Micropus amphibola A. Gray -- not accepted -- Mt. Diablo cottonseed
  Micropus amphibolus A. Gray -- accepted -- Mt. Diablo cottonseed
  Micropus californicus Fisch. & C.A. Mey. -- accepted -- q-tips
  Micropus californicus var. californicus Fisch. & C.A. Mey. -- accepted -- q-tips
  Micropus californicus var. subvestitus A. Gray -- accepted -- q-tips
  Micropus dasycarpa (Griseb.) P. Beauv. -- accepted -- desert cottonweed
  Microseris D. Don -- accepted -- silverpuffs, microseris
  Microseris acuminata Greene -- accepted -- Sierra foothill silverpuffs
  Microseris alpestris (A. Gray) Q. Jones ex Cronquist -- not accepted
  Microseris bigelovii (A. Gray) Sch. Bip. -- accepted -- coastal silverpuffs
  Microseris borealis (Bong.) Sch. Bip. -- accepted -- apargidium
  Microseris campestris Greene -- accepted -- San Joaquin silverpuffs
  Microseris cuspidata (Pursh) Sch. Bip. -- not accepted
  Microseris decipiens K.L. Chambers -- not accepted
  Microseris douglasii (DC.) Sch. Bip. -- accepted -- Douglas' silverpuffs
  Microseris douglasii ssp. douglasii (DC.) Sch. Bip. -- accepted -- Douglas' silverpuffs
  Microseris douglasii ssp. platycarpha (A. Gray) K.L. Chambers -- accepted -- Douglas' silverpuffs
  Microseris douglasii ssp. tenella (A. Gray) K.L. Chambers -- accepted -- Douglas' silverpuffs
  Microseris douglasii var. platycarpha (A. Gray) B.L. Turner -- not accepted
  Microseris elegans Greene ex A. Gray -- accepted -- elegant silverpuffs
  Microseris heterocarpa (Nutt.) K.L. Chambers -- not accepted
  Microseris howellii A. Gray -- accepted -- Howell's silverpuffs
  Microseris laciniata (Hook.) Sch. Bip. -- accepted -- cutleaf silverpuffs
  Microseris laciniata ssp. detlingii K.L. Chambers -- accepted -- Detling's silverpuffs
  Microseris laciniata ssp. laciniata (Hook.) Sch. Bip. -- accepted -- cutleaf silverpuffs
  Microseris laciniata ssp. leptosepala (Nutt.) K.L. Chambers -- accepted -- cutleaf silverpuffs
  Microseris laciniata ssp. siskiyouensis K.L. Chambers -- accepted -- cutleaf silverpuffs
  Microseris lindleyi (DC.) A. Gray -- not accepted
  Microseris linearifolia (Nutt.) Sch. Bip. -- not accepted
  Microseris nigrescens L.F. Hend. -- not accepted
  Microseris nutans (Hook.) Sch. Bip. -- accepted -- nodding microseris, nodding silverpuffs
  Microseris nutans ssp. nutans (Hook.) Sch. Bip. -- not accepted -- nodding silverpuffs
  Microseris nutans ssp. siskiyouensis K.L. Chambers -- not accepted
  Microseris paludosa (Greene) J.T. Howell -- accepted -- marsh silverpuffs
  Microseris sylvatica (Benth.) Sch. Bip. -- accepted -- sylvan scorzonella
  Microseris troximoides A. Gray -- not accepted
  Mikania Willd. -- accepted -- hempvine, mikania
  Mikania angulosa Raf. -- not accepted
  Mikania batatifolia auct. non DC. -- not accepted -- southern hempvine
  Mikania batatifolia DC. -- accepted
  Mikania congesta DC. -- accepted -- guaco
  Mikania cordata (Burm. f.) B.L. Rob. -- accepted -- heartleaf hempvine, mile-a-minute
  Mikania cordifolia (L. f.) Willd. -- accepted -- Florida Keys hempvine
  Mikania fragilis Urb. -- accepted -- fragile hempvine
  Mikania micrantha Kunth -- accepted -- bittervine, Chinese creeper, kwalo koburu, liane americaine, ovaova, wa mbosuvu, mile-a-minute
  Mikania odoratissima Urb. -- accepted -- fragrant hempvine
  Mikania pachyphylla Urb. -- accepted -- Luquillo Mountain hempvine
  Mikania porosa Urb. -- accepted -- Puerto Rico hempvine
  Mikania scandens (L.) Willd. -- accepted -- climbing hempvine, climbing hempweed
  Mikania scandens var. pubescens (Nutt.) Torr. & A. Gray -- not accepted
  Mikania stevensiana Britton -- accepted -- Maricao River hempvine
  Mirasolia diversifolia Hemsl. -- not accepted
  Molina salicifolia Ruiz & Pav. -- not accepted
  Monolopia DC. -- accepted -- monolopia
  Monolopia congdonii (A. Gray) B.G. Baldw. -- accepted -- San Joaquin woollythread
  Monolopia gracilens A. Gray -- accepted -- woodland monolopia
  Monolopia lanceolata Nutt. -- accepted -- common monolopia
  Monolopia major DC. -- accepted -- cupped monolopia
  Monolopia stricta Crum -- accepted -- Crum's monolopia
  Monoptilon Torr. & A. Gray -- accepted -- desertstar, monoptilon
  Monoptilon bellidiforme Torr. & A. Gray ex A. Gray -- accepted -- daisy desertstar, Mojave desertstar
  Monoptilon bellioides (A. Gray) H.M. Hall -- accepted -- Mojave desertstar, desertstar
  Montagnaea hibiscifolia Benth. -- not accepted
  Montanoa Llave & Lex. -- accepted -- montanoa
  Montanoa hibiscifolia (Benth.) Standl. -- accepted -- treedaisy, montanoa, tree daisy
  Mulgedium Cass. -- accepted
  Mulgedium floridanum (L) DC -- not accepted
  Mulgedium oblongifolium (Nutt.) Reveal -- accepted -- blue lettuce
  Mulgedium pulchellum (Pursh) G. Don -- not accepted
  Mulgedium spicatum auct. non (Lam.) Small -- not accepted
  Mulgedium spicatum var. integrifolium (Torr. & A. Gray) Small -- not accepted
  Mulgedium villosum (Jacq.) Small -- not accepted
  Munzothamnus P.H. Raven -- accepted
  Munzothamnus blairii (Munz & I.M. Johnst.) P.H. Raven -- accepted -- Blair's wirelettuce
  Mycelis Cass. -- accepted -- mycelis
  Mycelis muralis (L.) Dumort. -- accepted -- wall-lettuce
  Nabalus albus (L.) Hook. -- not accepted
  Nabalus altissimus (L.) Hook. -- not accepted
  Nabalus asperus (Michx.) Torr. & A. Gray -- not accepted
  Nabalus boottii DC. -- not accepted
  Nabalus crepidineus (Michx.) DC. -- not accepted
  Nabalus cylindricus Small -- not accepted
  Nabalus integrifolius Cass. -- not accepted
  Nabalus nanus (Bigelow) DC. -- not accepted
  Nabalus racemosus (Michx.) DC. -- not accepted
  Nabalus roanensis Chick. -- not accepted
  Nabalus serpentarius (Pursh) Hook. -- not accepted
  Nabalus trifoliolatus Cass. -- not accepted
  Nabalus virgatus (Michx.) DC. -- not accepted
  Nardosmia arctica (A.E. Porsild) A. Löve & D. Löve -- not accepted
  Nardosmia japonica Siebold & Zucc. -- not accepted
  Nardosmia vitifolia (Greene) A. Löve & D. Löve -- not accepted
  Neonesomia Urbatsch & R.P. Roberts -- accepted
  Neonesomia palmeri (A. Gray) Urbatsch & R.P. Roberts -- accepted -- Texas desert goldenrod, Texas goldenweed
  Nestotus R.P. Roberts, Urbatsch & Neubig -- accepted -- goldenweed
  Nestotus macleanii (Brandegee) R.P. Roberts, Urbatsch & Neubig -- accepted -- Maclean's goldenweed
  Nestotus stenophyllus (A. Gray) R.P. Roberts, Urbatsch & Neubig -- accepted -- narrowleaf mock goldenweed
  Neurolaena R. Br. -- accepted -- neurolaena
  Neurolaena lobata (L.) Cass. -- accepted -- sepi
  Nicolletia A. Gray -- accepted -- hole-in-the-sand plant, nicolletia
  Nicolletia edwardsii A. Gray -- accepted -- Edwards' hole-in-the-sand plant, Edwards' hole in the sand plant
  Nicolletia occidentalis A. Gray -- accepted -- Mojave hole-in-the-sand plant
  Nipponanthemum (Kitam.) Kitam. -- accepted
  Nipponanthemum nipponicum (Franch. ex Maxim.) Kitam. -- accepted -- Nippon daisy
  Nocca mollis (Cav.) Jacq. -- not accepted
  Nothocalais (A. Gray) Greene -- accepted -- prairie-dandelion, nothocalais
  Nothocalais alpestris (A. Gray) K.L. Chambers -- accepted -- alpine lake prairie-dandelion
  Nothocalais cuspidata (Pursh) Greene -- accepted -- sharppoint prairie-dandelion, microseris, wavy-leaf prairie-dandelion, sharppoint microseris
  Nothocalais nigrescens (L.F. Hend.) A. Heller -- accepted -- meadow prairie-dandelion
  Nothocalais troximoides (A. Gray) Greene -- accepted -- weevil prairie-dandelion, false agoseris
  Oclemena Greene -- accepted -- aster
  Oclemena acuminata (Michx.) Greene -- accepted -- whorled wood aster
  Oclemena nemoralis (Aiton) Greene -- accepted -- bog aster
  Oclemena reticulata (Pursh) G.L. Nesom -- accepted -- pine barren whitetop aster, pinebarren whitetop aster
  Oclemena X blakei (Porter) G.L. Nesom -- accepted
  Odontotrichum decompositum (A. Gray) Rydb. -- not accepted
  Oedera trinervia Spreng. -- not accepted
  Oglifa arizonica (A. Gray) Chrtek & Holub -- not accepted
  Oglifa arvensis (L.) Cass. -- not accepted
  Oglifa californica (Nutt.) Rydb. -- not accepted
  Oglifa depressa (A. Gray) Chrtek & Holub -- not accepted
  Oglifa gallica (L.) Chrtek & Holub -- not accepted
  Oglifa minima (Sm.) Rchb. -- not accepted
  Olearia Moench -- accepted -- daisy bush
  Olearia allomii T. Kirk -- accepted -- daisy bush
  Olearia cheesmanii Cockayne & Allan -- accepted -- daisy bush
  Oligoneuron Small -- accepted -- goldenrod
  Oligoneuron album (Nutt.) G.L. Nesom -- not accepted -- prairie goldenrod
  Oligoneuron canescens Rydb. -- not accepted
  Oligoneuron corymbosum var. humile (Porter) Beaudry & Kapoor -- not accepted
  Oligoneuron grandiflorum (Raf.) Small -- not accepted
  Oligoneuron houghtonii (Torr. & A. Gray ex A. Gray) G.L. Nesom -- not accepted -- Houghton's goldenrod
  Oligoneuron jacksonii (Kuntze) Small -- not accepted
  Oligoneuron nitidum (Torr. & A. Gray) Small -- not accepted -- shiny goldenrod
  Oligoneuron ohioense (Frank ex Riddell) G.N. Jones -- not accepted -- Ohio goldenrod
  Oligoneuron riddellii (Frank ex Riddell) Rydb. -- not accepted -- Riddell's goldenrod
  Oligoneuron rigidum (L.) Small -- not accepted -- stiff goldenrod
  Oligoneuron rigidum var. glabratum (E.L. Braun) G.L. Nesom -- not accepted -- stiff goldenrod
  Oligoneuron rigidum var. humile (Porter) G.L. Nesom -- not accepted -- stiff goldenrod, hardleaf goldenrod
  Oligoneuron rigidum var. rigidum (L.) Small -- not accepted -- stiff goldenrod
  Oligoneuron X bernardii (B. Boivin) G.L. Nesom -- not accepted
  Oligoneuron X krotkovii (B. Boivin) G.L. Nesom -- accepted
  Oligoneuron X lutescens (Lindl. ex DC.) G.L. Nesom -- not accepted
  Oligosporus campestris (L.) Cass. -- not accepted
  Oligosporus campestris ssp. caudatus (Michx.) W.A. Weber -- not accepted
  Oligosporus campestris ssp. pacificus (Nutt.) W.A. Weber -- not accepted
  Oligosporus caudatus (Michx.) Poljakov -- not accepted
  Oligosporus dracunculus (L.) Poljakov -- not accepted
  Oligosporus dracunculus ssp. dracunculinus (S. Watson) W.A. Weber -- not accepted
  Oligosporus dracunculus ssp. glaucus (Pall. ex Willd.) A. Löve & D. Löve -- not accepted
  Oligosporus filifolius (Torr.) W.A. Weber -- not accepted
  Oligosporus groenlandicus (Hornem.) Á. Löve & D. Löve -- not accepted
  Oligosporus pacificus (Nutt.) Poljakov -- not accepted
  Oligosporus pedatifidus (Nutt.) Poljakov -- not accepted
  Omalotheca Cass. -- accepted -- arctic cudweed
  Omalotheca norvegica (Gunnerus) Sch. Bip. & F.W. Schultz -- accepted -- Norwegian arctic cudweed
  Omalotheca supina (L) DC -- accepted -- alpine arctic cudweed
  Omalotheca sylvatica (L.) Sch. Bip. & F.W. Schultz -- accepted -- woodland arctic cudweed
  Oncosiphon Källersjö -- accepted -- oncosiphon
  Oncosiphon piluliferum (L. f.) Källersjö -- accepted -- stinknet
  Oncosiphon suffruticosum (L.) Källersjö -- accepted -- shrubby mayweed
  Onopordum L. -- accepted -- cottonthistle, cotton thistle
  Onopordum acanthium L. -- accepted -- Scotch cottonthistle, cotton thistle, heraldic thistle, Scotch cotton thistle, Scotch thistle
  Onopordum acanthium ssp. acanthium L. -- accepted -- Scotch thistle
  Onopordum illyricum L. -- accepted -- Illyrian cottonthistle
  Onopordum tauricum Willd. -- accepted -- bull cottonthistle, taurus cotton thistle, Scotch thistle
  Oonopsis (Nutt.) Greene -- accepted -- false goldenweed
  Oonopsis engelmannii (A. Gray) Greene -- accepted -- Engelmann's false goldenweed
  Oonopsis foliosa (A. Gray) Greene -- accepted -- leafy false goldenweed
  Oonopsis foliosa var. foliosa (A. Gray) Greene -- accepted -- leafy false goldenweed
  Oonopsis foliosa var. monocephala (A. Nelson) Kartesz & Gandhi -- accepted -- Raven Ridge false goldenweed
  Oonopsis multicaulis (Nutt.) Greene -- accepted -- branched false goldenweed
  Oonopsis puebloensis ? -- not accepted
  Oonopsis wardii (A. Gray) Greene -- accepted -- Ward's false goldenweed
  Oreastrum elatum Greene -- not accepted
  Oreochrysum Rydb. -- accepted -- goldenrod
  Oreochrysum parryi (A. Gray) Rydb. -- accepted -- Parry's goldenrod
  Oreostemma Greene -- accepted -- aster, oreostemma
  Oreostemma alpigenum (Torr. & A. Gray) Greene -- accepted -- tundra aster, alpine aster
  Oreostemma alpigenum ssp. haydenii (Porter) Semple -- not accepted
  Oreostemma alpigenum var. alpigenum (Torr. & A. Gray) Greene -- accepted -- tundra aster
  Oreostemma alpigenum var. andersonii (A. Gray) G.L. Nesom -- accepted -- tundra aster, alpine aster
  Oreostemma alpigenum var. haydenii (Porter) G.L. Nesom -- accepted -- tundra aster, alpine aster
  Oreostemma elatum (Greene) Greene -- accepted -- Plumas alpine aster
  Oreostemma peirsonii (C.W. Sharsmith) G.L. Nesom -- accepted -- Peirson's aster
  Ormenis mixta (L.) Dumort. -- not accepted
  Orochaenactis Coville -- accepted -- orochaenactis
  Orochaenactis thysanocarpha (A. Gray) Coville -- accepted -- California mountainpincushion
  Orthopappus angustifolius (Sw.) Gleason -- not accepted
  Osmadenia Nutt. -- accepted -- osmadenia
  Osmadenia tenella Nutt. -- accepted -- false rosinweed
  Osmia borinquensis Britton -- not accepted
  Osmia corymbosa (Aubl.) Britton & P. Wilson -- not accepted
  Osmia frustrata (B.L. Rob.) Small -- not accepted
  Osmia geraniifolia (Urb.) Britton & P. Wilson -- not accepted
  Osmia ivifolia (L.) Sch. Bip. -- not accepted
  Osmia odorata (L.) Sch. Bip. -- not accepted
  Osmia sinuata (Lam.) Britton & P. Wilson -- not accepted
  Osteospermum L. -- accepted -- daisybush
  Osteospermum calendulaceum L. f. -- accepted -- stinking roger
  Osteospermum ecklonis (DC.) Norl. -- accepted -- blue and white daisybush
  Osteospermum fruticosum (L.) Norl. -- accepted -- shrubby daisybush
  Osteospermum muricatum E. Mey. ex DC. -- accepted
  Osteospermum sinuatum (DC.) Norl. -- accepted -- glandular cape marigold
  Osteospermum spinescens Thunb. -- accepted
  Osteospermum uvedalia L. -- not accepted
  Othake callosa (Nutt.) Bush -- not accepted
  Othake sphacelata (Nutt. ex Torr.) Rydb. -- not accepted
  Oxytenia Nutt. -- accepted
  Oxytenia acerosa Nutt. -- accepted -- copperweed
  Packera Á. Löve & D. Löve -- accepted -- ragwort
  Packera actinella (Greene) W.A. Weber & A. Löve -- not accepted
  Packera anonyma (Alph. Wood) W.A. Weber & Á. Löve -- accepted -- Small's ragwort
  Packera antennariifolia (Britton) W.A. Weber & Á. Löve -- accepted -- shale barren ragwort, shalebarren ragwort
  Packera aurea (L.) Á. Löve & D. Löve -- accepted -- golden ragwort
  Packera bernardina (Greene) W.A. Weber & Á. Löve -- accepted -- San Bernardino ragwort
  Packera bolanderi (A. Gray) W.A. Weber & Á. Löve -- accepted -- Bolander's ragwort
  Packera bolanderi var. bolanderi (A. Gray) W.A. Weber & Á. Löve -- accepted -- Bolander's ragwort
  Packera bolanderi var. harfordii (Greenm.) D.K. Trock & T.M. Barkley -- accepted -- Harford's ragwort
  Packera breweri (Burtt Davy) W.A. Weber & Á. Löve -- accepted -- Brewer's ragwort
  Packera buekii D.K. Trock & T.M. Barkley -- not accepted
  Packera cana (Hook.) W.A. Weber & Á. Löve -- accepted -- woolly groundsel
  Packera cardamine (Greene) W.A. Weber & Á. Löve -- accepted -- bittercress ragwort
  Packera castoreus (S.L. Welsh) Kartesz -- accepted -- Beaver Mountain ragwort
  Packera clevelandii (Greene) W.A. Weber & Á. Löve -- accepted -- Cleveland's ragwort
  Packera contermina (Greenm.) J.F. Bain -- accepted -- northwestern groundsel
  Packera crocata (Rydb.) W.A. Weber & Á. Löve -- accepted -- saffron ragwort
  Packera cymbalaria (Pursh) W.A. Weber & Á. Löve -- accepted -- dwarf arctic ragwort
  Packera cymbalarioides (Nutt.) W.A. Weber & Á. Löve -- not accepted -- cleftleaf groundsel
  Packera cynthioides (Greene) W.A. Weber & Á. Löve -- accepted -- White Mountain ragwort
  Packera debilis (Nutt.) W.A. Weber & Á. Löve -- accepted -- weak groundsel
  Packera dimorphophylla (Greene) W.A. Weber & Á. Löve -- accepted -- splitleaf groundsel
  Packera dimorphophylla ssp. dimorphophylla (Greene) W.A. Weber & Á. Löve -- not accepted -- splitleaf groundsel
  Packera dimorphophylla ssp. intermedia (T.M. Barkley) W.A. Weber & Á. Löve -- not accepted
  Packera dimorphophylla var. dimorphophylla (Greene) W.A. Weber & Á. Löve -- accepted -- splitleaf groundsel
  Packera dimorphophylla var. intermedia (T.M. Barkley) D.K. Trock & T.M. Barkley -- accepted -- splitleaf groundsel
  Packera dimorphophylla var. paysonii (T.M. Barkley) D.K. Trock & T.M. Barkley -- accepted -- Payson's groundsel
  Packera eurycephala (Torr. & A. Gray) W.A. Weber & Á. Löve -- accepted -- widehead groundsel
  Packera eurycephala var. eurycephala (Torr. & A. Gray) W.A. Weber & Á. Löve -- accepted -- widehead groundsel
  Packera eurycephala var. lewisrosei (J.T. Howell) J.F. Bain -- accepted -- Lewis' groundsel
  Packera fendleri (A. Gray) W.A. Weber & Á. Löve -- accepted -- Fendler's ragwort
  Packera fernaldii (Greenm.) Á. Löve & D. Löve -- not accepted
  Packera flettii (Wiegand) W.A. Weber & Á. Löve -- accepted -- Flett's ragwort
  Packera franciscana (Greene) W.A. Weber & Á. Löve -- accepted -- San Francisco Peaks ragwort
  Packera ganderi (T.M. Barkley & R.M. Beauch.) W.A. Weber & Á. Löve -- accepted -- Gander's ragwort
  Packera glabella (Poir.) C. Jeffrey -- accepted -- butterweed
  Packera greenei (A. Gray) W.A. Weber & Á. Löve -- accepted -- flame ragwort
  Packera hartiana (A. Heller) W.A. Weber & Á. Löve -- accepted -- Hart's ragwort, Mogollon Mountain ragwort
  Packera hesperia (Greene) W.A. Weber & Á. Löve -- accepted -- western ragwort
  Packera hyperborealis (Greenm.) Á. Löve & D. Löve -- accepted -- northern groundsel
  Packera indecora (Greene) Á. Löve & D. Löve -- accepted -- elegant groundsel
  Packera ionophylla (Greene) W.A. Weber & Á. Löve -- accepted -- Tehachapi ragwort
  Packera layneae (Greene) W.A. Weber & Á. Löve -- accepted -- Layne's ragwort
  Packera macounii (Greene) W.A. Weber & Á. Löve -- accepted -- Siskiyou Mountain ragwort
  Packera malmstenii (S.F. Blake ex Tidestr.) Kartesz -- accepted -- Podunk ragwort
  Packera millefolia (Torr. & A. Gray) W.A. Weber & Á. Löve -- accepted -- piedmont ragwort
  Packera millelobata (Rydb.) W.A. Weber & Á. Löve -- accepted -- Uinta ragwort
  Packera moresbiensis (Calder & Roy L. Taylor) J.F. Bain -- not accepted
  Packera multilobata (Torr. & A. Gray ex A. Gray) W.A. Weber & Á. Löve -- accepted -- lobeleaf groundsel
  Packera musiniensis (S.L. Welsh) Trock -- accepted -- Musinea ragwort
  Packera neomexicana (A. Gray) W.A. Weber & Á. Löve -- accepted -- New Mexico groundsel
  Packera neomexicana var. metcalfei (Greene) D.K. Trock & T.M. Barkley -- not accepted -- Metcalf's groundsel
  Packera neomexicana var. mutabilis (Greene) W.A. Weber & Á. Löve -- accepted -- New Mexico groundsel, Metcalf's groundsel
  Packera neomexicana var. neomexicana (A. Gray) W.A. Weber & Á. Löve -- accepted -- New Mexico groundsel
  Packera neomexicana var. toumeyi (Greene) D.K. Trock & T.M. Barkley -- accepted -- Toumey's groundsel
  Packera obovata (Muhl. ex Willd.) W.A. Weber & Á. Löve -- accepted -- roundleaf ragwort
  Packera ogotorukensis (Packer) Á. Löve & D. Löve -- accepted -- Ogotoruk Creek ragwort
  Packera oodes (Rydb.) W.A. Weber -- not accepted
  Packera pauciflora (Pursh) Á. Löve & D. Löve -- accepted -- alpine groundsel
  Packera paupercula (Michx.) Á. Löve & D. Löve -- accepted -- balsam groundsel
  Packera plattensis (Nutt.) W.A. Weber & Á. Löve -- accepted -- prairie groundsel
  Packera porteri (Greene) C. Jeffrey -- accepted -- Porter's groundsel
  Packera pseudaurea (Rydb.) W.A. Weber & Á. Löve -- accepted -- falsegold groundsel
  Packera pseudaurea ssp. flavula (Greene) W.A. Weber & Á. Löve -- not accepted
  Packera pseudaurea var. flavula (Greene) D.K. Trock & T.M. Barkley -- accepted -- falsegold groundsel
  Packera pseudaurea var. pseudaurea (Rydb.) W.A. Weber & Á. Löve -- accepted -- falsegold groundsel
  Packera pseudaurea var. semicordata (Mack. & Bush) D.K. Trock & T.M. Barkley -- accepted -- falsegold groundsel
  Packera quaerens (Greene) W.A. Weber & Á. Löve -- not accepted -- Mogollon Mountain ragwort
  Packera quercetorum (Greene) C. Jeffrey -- accepted -- Oak Creek ragwort
  Packera resedifolia (Less.) Á. Löve & D. Löve -- not accepted
  Packera sanguisorboides (Rydb.) W.A. Weber & Á. Löve -- accepted -- burnet ragwort
  Packera schweinitziana (Nutt.) W.A. Weber & Á. Löve -- accepted -- Schweinitz's ragwort
  Packera spellenbergii (T.M. Barkley) C. Jeffrey -- accepted -- Carrizo Creek ragwort
  Packera streptanthifolia (Greene) W.A. Weber & Á. Löve -- accepted -- Rocky Mountain groundsel, cleftleaf groundsel
  Packera streptanthifolia var. rubricaulis (Greene) Dorn -- not accepted
  Packera streptanthifolia var. streptanthifolia (Greene) W.A. Weber & Á. Löve -- not accepted
  Packera subnuda (DC.) D.K. Trock & T.M. Barkley -- accepted -- Buek's groundsel
  Packera subnuda var. moresbiensis (Calder & Roy L. Taylor) Trock -- accepted -- cleftleaf ragwort
  Packera subnuda var. subnuda (DC.) D.K. Trock & T.M. Barkley -- accepted
  Packera tampicana (DC.) C. Jeffrey -- accepted -- Great Plains ragwort
  Packera texana O'Kennon & Trock -- accepted
  Packera tomentosa (Michx.) C. Jeffrey -- accepted -- woolly ragwort
  Packera tridenticulata (Rydb.) W.A. Weber & Á. Löve -- accepted -- threetooth ragwort
  Packera werneriifolia (A. Gray) W.A. Weber & Á. Löve -- accepted -- hoary groundsel
  Packera werneriifolia var. alpina (A. Gray) Dorn -- not accepted
  Palafoxia Lag. -- accepted -- palafox
  Palafoxia arida B.L. Turner & Morris -- accepted -- desert palafox, giant Spanish needle, desert needles, desert palafoxia
  Palafoxia arida var. arida B.L. Turner & Morris -- not accepted -- desert palafox, desert palafoxia
  Palafoxia arida var. gigantea (M.E. Jones) B.L. Turner & Morris -- not accepted -- giant Spanish needle, desert palafox
  Palafoxia callosa (Nutt.) Torr. & A. Gray -- accepted -- small palafox, small palafoxia
  Palafoxia callosa var. bella (Cory) Shinners -- not accepted
  Palafoxia feayi A. Gray -- accepted -- Feay's palafox
  Palafoxia hookeriana Torr. & A. Gray -- accepted -- sand palafox, showy palafoxia
  Palafoxia hookeriana var. hookeriana Torr. & A. Gray -- not accepted -- sand palafox
  Palafoxia hookeriana var. minor Shinners -- not accepted -- sand palafox
  Palafoxia integrifolia (Nutt.) Torr. & A. Gray -- accepted -- coastal plain palafox, coastalplain palafox
  Palafoxia linearis (Cav.) Lag. -- accepted -- palafox
  Palafoxia linearis var. gigantea M.E. Jones -- not accepted
  Palafoxia macrolepis (Rydb.) Cory -- not accepted
  Palafoxia reverchonii (Bush) Cory -- accepted -- Reverchon's palafox
  Palafoxia riograndensis Cory -- accepted -- Rio Grande palafox
  Palafoxia rosea (Bush) Cory -- accepted -- rosy palafox, pink palafoxia
  Palafoxia rosea var. ambigua Shinners -- not accepted
  Palafoxia rosea var. macrolepis (Rydb.) B.L. Turner & Morris -- not accepted -- rosy palafox
  Palafoxia rosea var. papposa Shinners -- not accepted
  Palafoxia rosea var. rosea (Bush) Cory -- not accepted -- rosy palafox
  Palafoxia sphacelata (Nutt. ex Torr.) Cory -- accepted -- othake, rayed palafoxia
  Palafoxia texana DC. -- accepted -- Texas palafox
  Palafoxia texana var. ambigua (Shinners) B.L. Turner & Morris -- not accepted -- Texas palafox
  Palafoxia texana var. macrolepis (Rydb.) Shinners -- not accepted
  Palafoxia texana var. texana DC. -- not accepted -- Texas palafox
  Palafoxia tripteris (DC.) Shinners -- not accepted
  Palafoxia tripteris var. brevis Shinners -- not accepted
  Parasenecio W.W. Sm. & Small -- accepted -- Indian plantain
  Parasenecio auriculata (DC.) J.R. Grant -- accepted -- eared Indian plantain
  Parthenice A. Gray -- accepted -- parthenice
  Parthenice mollis A. Gray -- accepted -- annual monsterwort
  Parthenium L. -- accepted -- feverfew
  Parthenium alpinum (Nutt.) Torr. & A. Gray -- accepted -- alpine feverfew, Arkansas River feverfew
  Parthenium alpinum var. ligulatum M.E. Jones -- not accepted
  Parthenium alpinum var. tetraneuris (Barneby) Rollins -- not accepted
  Parthenium argentatum A. Gray -- accepted -- guayule
  Parthenium auriculatum Britton -- not accepted
  Parthenium confertum A. Gray -- accepted -- Gray's feverfew, gray feverfew
  Parthenium confertum var. confertum A. Gray -- not accepted -- Gray's feverfew
  Parthenium confertum var. divaricatum Rollins -- not accepted -- Gray's feverfew
  Parthenium confertum var. intermedium Mears -- not accepted -- Gray's feverfew
  Parthenium confertum var. lyratum (A. Gray) Rollins -- not accepted -- Gray's feverfew
  Parthenium confertum var. microcephalum Rollins -- not accepted -- Gray's feverfew
  Parthenium hispidum Raf. -- not accepted
  Parthenium hispidum var. auriculatum (Britton) Rollins -- not accepted
  Parthenium hysterophorus L. -- accepted -- Santa Maria feverfew, ragweed parthenium, whitetop weed
  Parthenium hysterophorus var. lyratum A. Gray -- not accepted
  Parthenium incanum Kunth -- accepted -- mariola
  Parthenium integrifolium L. -- accepted -- wild quinine, American feverfew
  Parthenium integrifolium var. auriculatum (Britton) Cornelius ex Cronquist -- not accepted -- wild quinine
  Parthenium integrifolium var. henryanum Mears -- not accepted -- wild quinine
  Parthenium integrifolium var. hispidum (Raf.) Mears -- not accepted -- wild quinine
  Parthenium integrifolium var. integrifolium L. -- not accepted -- wild quinine
  Parthenium integrifolium var. mabryanum Mears -- not accepted -- wild quinine
  Parthenium ligulatum (M.E. Jones) Barneby -- accepted -- Colorado feverfew
  Parthenium lobatum Buckley -- not accepted
  Parthenium lyratum (A. Gray) A. Gray -- not accepted
  Parthenium radfordii Mears -- not accepted
  Parthenium repens Eggert -- not accepted
  Parthenium tetraneuris Barneby -- not accepted -- Arkansas River feverfew
  Pascalia Ortega -- accepted -- Pascalia
  Pascalia glauca Ortega -- accepted -- beach creeping oxeye
  Pectis L. -- accepted -- chinchweed, fetid marigold, cinchweed, fetidmarigold
  Pectis angustifolia Torr. -- accepted -- lemonscent, narrowleaf pectis
  Pectis angustifolia var. angustifolia Torr. -- accepted -- narrowleaf pectis, lemonscent
  Pectis angustifolia var. fastigiata (A. Gray) Keil -- accepted -- lemonscent
  Pectis angustifolia var. tenella (DC.) Keil -- accepted -- lemonscent
  Pectis carthusianorum Less. -- accepted -- Caribbean chinchweed, Caribbean cinchweed
  Pectis ciliaris L. -- accepted -- donkeyweed
  Pectis coulteri Harv. & A. Gray -- accepted -- Coulter's cinchweed
  Pectis cylindrica (Fernald) Rydb. -- accepted -- Sonoran chinchweed, Sonoran cinchweed
  Pectis elongata Kunth -- accepted -- tropical chinchweed, tropical cinchweed
  Pectis elongata var. elongata Kunth -- accepted -- tropical chinchweed
  Pectis elongata var. floribunda (A. Rich.) Keil -- accepted -- tropical chinchweed, tropical cinchweed
  Pectis febrifuga H.C. Hall -- not accepted
  Pectis filipes Harv. & A. Gray -- accepted -- fivebract chinchweed, fivebract cinchweed, five-bract cinchweed
  Pectis filipes var. filipes Harv. & A. Gray -- accepted
  Pectis filipes var. subnuda Fernald -- accepted -- fivebract chinchweed, fivebract cinchweed
  Pectis floribunda A. Rich. -- not accepted
  Pectis glaucescens (Cass.) Keil -- accepted -- sanddune chinchweed, sanddune cinchweed
  Pectis humifusa Sw. -- accepted -- yerba de San Juan
  Pectis imberbis A. Gray -- accepted -- beardless chinchweed, beardless cinchweed
  Pectis leptocephala (Cass.) Urb. -- not accepted
  Pectis linearifolia Urb. -- accepted -- Florida chinchweed, Florida cinchweed
  Pectis linearis Llave -- accepted -- West Indian chinchweed, West Indian cinchweed
  Pectis linifolia L. -- accepted -- romero macho, narrowleaf lemonweed
  Pectis longipes A. Gray -- accepted -- longstalk chinchweed, mat cinchweed, longstalk cinchweed
  Pectis multisetosa Rydb. -- not accepted
  Pectis palmeri S. Watson -- not accepted
  Pectis papposa Harv. & A. Gray -- accepted -- manybristle chinchweed, cinchweed, manybristle cinchweed, cinchweed fetidmarigold
  Pectis papposa var. grandis Keil -- accepted -- manybristle chinchweed, manybristle cinchweed
  Pectis papposa var. papposa Harv. & A. Gray -- accepted -- manybristle chinchweed, many-bristle cinchweed, manybristle cinchweed
  Pectis portoricensis Urb. -- not accepted
  Pectis postrata var. cylindrica Fernald -- not accepted
  Pectis prostrata Cav. -- accepted -- spreading chinchweed, spreading cinchweed
  Pectis prostrata var. cylindrica Fernald -- not accepted
  Pectis prostrata var. urceolata Fernald -- not accepted
  Pectis rusbyi Greene ex A. Gray -- accepted -- Rusby's chinchweed, Rusby's cinchweed
  Pectis tenella DC. -- not accepted
  Pectis tenuicaulis Urb. -- accepted -- island chinchweed, island cinchweed
  Pectis texana Cory -- not accepted
  Pectis X floridana Keil -- accepted -- hybrid Florida cinchweed
  Pentachaeta Nutt. -- accepted -- pygmydaisy
  Pentachaeta alsinoides Greene -- accepted -- tiny pygmydaisy
  Pentachaeta aphantochaeta (A. Gray) Greene -- not accepted
  Pentachaeta aurea Nutt. -- accepted -- golden chaetopappa
  Pentachaeta bellidiflora Greene -- accepted -- whiteray pygmydaisy, white-rayed pentachaeta
  Pentachaeta exilis (A. Gray) A. Gray -- accepted -- meager pygmydaisy
  Pentachaeta exilis ssp. aeolica Van Horn & Ornduff -- accepted -- meager pygmydaisy
  Pentachaeta exilis ssp. exilis (A. Gray) A. Gray -- accepted -- meager pygmydaisy
  Pentachaeta exilis var. aphantochaeta A. Gray -- not accepted
  Pentachaeta exilis var. discoidea A. Gray -- not accepted
  Pentachaeta exilis var. grayi Jeps. -- not accepted
  Pentachaeta fragilis Brandegee -- accepted -- fragile pygmydaisy
  Pentachaeta lyonii A. Gray -- accepted -- Lyon's pygmydaisy, Lyon's pentachaeta
  Pentachaeta orcuttii A. Gray -- not accepted
  Pentachaeta paleacea Greene -- not accepted
  Pentzia Thunb. -- accepted -- pentzia
  Pentzia incana (Thunb.) Kuntze -- accepted -- African sheepbush
  Pentzia lanata Hutch. -- accepted
  Pentzia sphaerocephala DC. -- accepted
  Pentzia virgata Less. -- not accepted
  Perezia Lagasca -- accepted
  Perezia microcephala (DC.) A. Gray -- not accepted
  Perezia multiflora (Humb. & Bonpl.) Less. -- accepted
  Perezia multiflora ssp. multiflora (Humb. & Bonpl.) Less. -- accepted
  Perezia nana A. Gray -- not accepted
  Perezia runcinata (Lag. ex D. Don) Lag. ex A. Gray -- not accepted
  Perezia sonchifolia Baker -- not accepted
  Perezia thurberi A. Gray -- not accepted
  Perezia wrightii A. Gray -- not accepted
  Pericallis Webb -- accepted -- ragwort
  Pericallis cuneata (L'Hér.) Bolle -- not accepted -- common ragwort
  Pericallis cuneata (DC.) Webb & Bethel. non (Roth) Webb & Bethel. -- not accepted
  Pericallis hybrida B. Nord. -- accepted -- common ragwort
  Pericallis murrayi (Bornm.) B. Nord. -- accepted
  Pericallis webbii (Sch. Bip.) Bolle -- accepted
  Pericome A. Gray -- accepted -- pericome
  Pericome caudata A. Gray -- accepted -- mountain tail-leaf, mountain leaftail, mountain taper leaf
  Pericome caudata var. glandulosa (Goodman) Harr. -- not accepted
  Pericome glandulosa Goodman -- not accepted
  Perityle Benth. -- accepted -- rockdaisy, rock daisy
  Perityle aglossa A. Gray -- accepted -- bluff rockdaisy
  Perityle ajoensis T.K. Todsen -- accepted -- Ajo rockdaisy
  Perityle ambrosiifolia Greene ex A. Powell & S.C. Yarborough -- accepted -- lace-leaved rockdaisy
  Perityle angustifolia (A. Gray) Shinners -- accepted -- narrow-leaved rockdaisy, rayless rockdaisy
  Perityle bisetosa (Torr. ex A. Gray) Shinners -- accepted -- twobristle rockdaisy, twospike rockdaisy
  Perityle bisetosa var. appressa A. Powell -- accepted -- twobristle rockdaisy, twospike rockdaisy
  Perityle bisetosa var. bisetosa (Torr. ex A. Gray) Shinners -- accepted -- twobristle rockdaisy, twospike rockdaisy
  Perityle bisetosa var. scalaris A. Powell -- accepted -- twobristle rockdaisy, twospike rockdaisy
  Perityle californica Benth. -- accepted -- California rockdaisy
  Perityle cernua (Greene) Shinners -- accepted -- Organ Mountain rockdaisy, nodding rockdaisy
  Perityle ciliata (L.H. Dewey) Rydb. -- accepted -- fringed rockdaisy, hairy rock-daisy
  Perityle cinerea (A. Gray) A. Powell -- accepted -- gray rockdaisy
  Perityle cochisensis (Niles) A. Powell -- accepted -- Cochise rockdaisy
  Perityle congesta (M.E. Jones) Shinners -- accepted -- Grand Canyon rockdaisy, compact rockdaisy, compacted rockdaisy
  Perityle coronopifolia A. Gray -- accepted -- crowfoot rockdaisy, Arizona rockdaisy
  Perityle dissecta (Torr.) A. Gray -- accepted -- dissected rockdaisy, slimlobe rockdaisy
  Perityle emoryi Torr. -- accepted -- Emory's rockdaisy, Emory's rocklily
  Perityle emoryi var. nuda (Torr.) A. Gray -- not accepted
  Perityle fastigiata (Brandegee) Shinners -- not accepted
  Perityle fosteri A. Powell -- accepted -- Foster's rockdaisy
  Perityle gilensis (M.E. Jones) J.F. Macbr. -- accepted -- Gila rockdaisy, Fish Creek rockdaisy
  Perityle gilensis var. gilensis (M.E. Jones) J.F. Macbr. -- accepted -- Gila rockdaisy, Fish Creek rockdaisy
  Perityle gilensis var. salensis A. Powell -- accepted -- Salt River rockdaisy, Fish Creek rockdaisy
  Perityle gracilis (M.E. Jones) Rydb. -- accepted -- three-lobed rockdaisy, grassleaf rockdaisy, grass-leaf rockdaisy, grasslike rockdaisy
  Perityle halimifolia (A. Gray) Shinners -- not accepted
  Perityle huecoensis A. Powell -- accepted -- Hueco rockdaisy, monarch rockdaisy
  Perityle intricata (Brandegee) Shinners -- accepted -- narrowleaf laphamia
  Perityle inyoensis (Ferris) A. Powell -- accepted -- Inyo rockdaisy
  Perityle lemmonii (A. Gray) J.F. Macbr. -- accepted -- Lemmon's rockdaisy
  Perityle lindheimeri (A. Gray) Shinners -- accepted -- Lindheimer's rockdaisy, bluffdaisy
  Perityle lindheimeri var. halimifolia (A. Gray) A. Powell -- accepted -- Lindheimer's rockdaisy, bluffdaisy
  Perityle lindheimeri var. lindheimeri (A. Gray) Shinners -- accepted -- Lindheimer's rockdaisy
  Perityle megalocephala (S. Watson) J.F. Macbr. -- accepted -- Nevada rockdaisy, limestone rockdaisy, bighead rockdaisy
  Perityle megalocephala var. intricata (Brandegee) A. Powell -- not accepted -- narrowleaf laphamia
  Perityle megalocephala var. megalocephala (S. Watson) J.F. Macbr. -- accepted -- Nevada rockdaisy, limestone rockdaisy
  Perityle megalocephala var. oligophylla A. Powell -- accepted -- small-leaved rockdaisy, limestone rockdaisy
  Perityle microglossa Benth. -- accepted -- shortray rockdaisy
  Perityle microglossa var. effusa A. Gray -- not accepted
  Perityle microglossa var. microglossa Benth. -- accepted -- shortray rockdaisy
  Perityle parryi A. Gray -- accepted -- Parry's rockdaisy, heartleaf rockdaisy
  Perityle plumigera Harv. & A. Gray -- not accepted
  Perityle quinqueflora (Steyerm.) Shinners -- accepted -- fiveflower rockdaisy
  Perityle rotundata (Rydb.) Shinners -- not accepted
  Perityle rupestris (A. Gray) Shinners -- accepted -- leafy rockdaisy
  Perityle rupestris var. albiflora A. Powell -- accepted -- leafy rockdaisy
  Perityle rupestris var. rupestris (A. Gray) Shinners -- accepted -- leafy rockdaisy
  Perityle saxicola (Eastw.) Shinners -- accepted -- Roosevelt Dam rockdaisy
  Perityle specuicola S.L. Welsh & Neese -- accepted -- alcove rockdaisy
  Perityle spilanthoides (Sch. Bip.) Rydb. -- not accepted
  Perityle stansburii (A. Gray) J.F. Macbr. -- not accepted -- Stansbury's rockdaisy
  Perityle stansburyi (A. Gray) J.F. Macbr. -- accepted -- Stansbury's rockdaisy
  Perityle staurophylla (Barneby) Shinners -- accepted -- New Mexico rockdaisy
  Perityle staurophylla var. homoflora T.K. Todsen -- accepted -- New Mexico rockdaisy
  Perityle staurophylla var. staurophylla (Barneby) Shinners -- accepted -- New Mexico rockdaisy
  Perityle tenella (M.E. Jones) J.F. Macbr. -- accepted -- Springdale rockdaisy
  Perityle vaseyi J.M. Coult. -- accepted -- Vasey's rockdaisy, margined rockdaisy
  Perityle villosa (S.F. Blake) Shinners -- accepted -- Hanaupah rockdaisy, Hanaupah laphamia
  Perityle vitreomontana Warnock -- accepted -- Glass Mountain rockdaisy
  Perityle warnockii A. Powell -- accepted -- Warnock's rockdaisy, river rockdaisy
  Petasites Mill. -- accepted -- butterbur
  Petasites alaskanus Rydb. -- not accepted
  Petasites arcticus A.E. Porsild -- not accepted
  Petasites corymbosus (R. Br.) Rydb. -- not accepted
  Petasites dentatus Blank. -- not accepted
  Petasites frigidus (L.) Fr. -- accepted -- arctic sweet coltsfoot, arctic sweet-colt's-foot
  Petasites frigidus ssp. arcticus (A.E. Porsild) Cody -- not accepted
  Petasites frigidus ssp. nivalis (Greene) Cody -- not accepted
  Petasites frigidus ssp. palmatus (Aiton) Cody -- not accepted
  Petasites frigidus var. corymbosus (R. Br.) Cronquist -- not accepted
  Petasites frigidus var. frigidus (L.) Fr. -- accepted -- arctic sweet coltsfoot
  Petasites frigidus var. hyperboreoides Hultén -- not accepted
  Petasites frigidus var. nivalis (Greene) Cronquist -- not accepted -- arctic sweet coltsfoot
  Petasites frigidus var. palmatus (Aiton) Cronquist -- accepted -- arctic sweet coltsfoot, arctic sweet-colt's-foot
  Petasites frigidus var. sagittatus (Banks ex Pursh) Chern. -- accepted -- arrowleaf sweet coltsfoot
  Petasites frigidus var. vitifolius (Greene) Chern. -- accepted
  Petasites gracilis Britton -- not accepted
  Petasites hookerianus (Nutt.) Rydb. -- not accepted
  Petasites hybridus (L.) G. Gaertn., B. Mey. & Scherb. -- accepted -- pestilence wort
  Petasites hyperboreus Rydb. -- not accepted
  Petasites japonicus (Siebold & Zucc.) Maxim. -- accepted -- Japanese sweet coltsfoot
  Petasites nivalis Greene -- not accepted
  Petasites nivalis ssp. vitifolius (Greene) Toman -- not accepted
  Petasites officinalis Moench -- not accepted
  Petasites palmatus (Aiton) A. Gray -- not accepted
  Petasites palmatus var. frigidus Macoun -- not accepted
  Petasites sagittatus (Banks ex Pursh) A. Gray -- not accepted -- arrow butterbur, arrow-leaf sweet-colt's-foot, arrowleaf sweet coltsfoot
  Petasites speciosus (Nutt.) Piper -- not accepted
  Petasites trigonophylla Greene -- not accepted
  Petasites vulgaris Hill -- not accepted
  Petasites warrenii H. St. John -- not accepted
  Petasites X vitifolius Greene (pro sp.) -- not accepted -- sweet coltsfoot
  Petradoria Greene -- accepted -- rockgoldenrod, rock goldenrod
  Petradoria discoidea L.C. Anderson -- not accepted
  Petradoria pumila (Nutt.) Greene -- accepted -- grassy rockgoldenrod, rock goldenrod
  Petradoria pumila ssp. graminea (Woot. & Standl.) L.C. Anderson -- accepted -- giant rockgoldenrod
  Petradoria pumila ssp. pumila (Nutt.) Greene -- accepted -- grassy rockgoldenrod, grassy rock goldenrod
  Petradoria pumila var. graminea (Woot. & Standl.) S.L. Welsh -- not accepted
  Peucephyllum A. Gray -- accepted -- pygmycedar, pygmy cedar
  Peucephyllum schottii A. Gray -- accepted -- Schott's pygmycedar, pygmy cedar, pygmycedar
  Phaethusa helianthoides (Michx.) Britton -- not accepted
  Phaethusa laciniata (Poir.) Small -- not accepted
  Phaethusa occidentalis (L.) Britton -- not accepted
  Phaethusa virginica (L.) Britton -- not accepted
  Phalacroseris A. Gray -- accepted -- mock dandelion
  Phalacroseris bolanderi A. Gray -- accepted -- Bolander's mock dandelion
  Phalacroseris bolanderi var. bolanderi A. Gray -- not accepted -- Bolander's mock dandelion
  Phalacroseris bolanderi var. coronata H.M. Hall -- not accepted -- Bolander's mock dandelion
  Phoebanthus S.F. Blake -- accepted -- false sunflower
  Phoebanthus grandiflorus (Torr. & A. Gray) S.F. Blake -- accepted -- Florida false sunflower
  Phoebanthus tenuifolius (Torr. & A. Gray) S.F. Blake -- accepted -- pineland false sunflower
  Phymaspermum Less. -- accepted
  Phymaspermum parvifolium (DC.) Benth. & Hook. f. -- accepted
  Picradenia helenioides Rydb. -- not accepted
  Picradenia odorata (DC.) Britton -- not accepted
  Picradenia richardsonii Hook. -- not accepted
  Picradenia richardsonii var. floribunda (A. Gray) W.A. Weber -- not accepted
  Picradeniopsis Rydb. ex Britton -- accepted -- bahia
  Picradeniopsis oppositifolia (Nutt.) Rydb. ex Britton -- accepted -- oppositeleaf bahia, opposite-leaf false bahia, plains bahia
  Picradeniopsis woodhousei (A. Gray) Rydb. -- accepted -- Woodhouse's bahia, Woodhouse's false bahia
  Picris L. -- accepted -- oxtongue
  Picris echioides L. -- not accepted -- bristly oxtongue
  Picris hieracioides L. -- accepted -- hawkweed oxtongue
  Picris hieracioides ssp. hieracioides L. -- not accepted -- hawkweed oxtongue
  Picris hieracioides ssp. hieracioides var. alpina Koidzumi -- not accepted -- hawkweed oxtongue
  Picris hieracioides ssp. kamtschatica (Ledeb.) Hultén -- not accepted -- hawkweed oxtongue
  Picris hieracioides var. alpina Koidzumi -- not accepted
  Picris kamtschatica Ledeb. -- not accepted
  Picris pauciflora Willd. -- accepted -- smallflower oxtongue
  Picris rhagadioloides (L.) Desf. -- accepted
  Picris sprengeriana (L.) Poir. -- accepted -- bitterweed
  Picrothamnus Nutt. -- accepted -- bud sagebrush
  Picrothamnus desertorum Nutt. -- accepted -- bud sagebrush
  Pinaropappus Less. -- accepted -- rocklettuce, rock lettuce
  Pinaropappus parvus S.F. Blake -- accepted -- small rocklettuce
  Pinaropappus roseus (Less.) Less. -- accepted -- white rocklettuce, white rock-lettuce
  Pinaropappus roseus var. foliosus (A. Heller) Shinners -- not accepted -- white rock lettuce, white rocklettuce
  Pinaropappus roseus var. roseus (Less.) Less. -- not accepted -- white rocklettuce
  Piptocarpha R. Br. -- accepted -- ashdaisy
  Piptocarpha tetrantha Urb. -- accepted -- mountain ashdaisy
  Piptocoma Cass. -- accepted -- velvetshrub
  Piptocoma acevedoi Pruski -- accepted -- Acevedo's velvetshrub
  Piptocoma antillana Urb. -- accepted -- Antilles velvetshrub
  Piptocoma rufescens auct. non Cass. -- not accepted
  Pityopsis Nutt. -- accepted -- silkgrass, pityopsis
  Pityopsis adenolepis (Fernald) Semple -- not accepted -- Carolina silkgrass
  Pityopsis aspera (Shuttlw. ex Small) Small -- accepted -- pineland silkgrass
  Pityopsis aspera var. adenolepis (Fernald) Semple & F.D. Bowers -- accepted -- Carolina silkgrass
  Pityopsis aspera var. aspera (Shuttlw. ex Small) Small -- accepted -- pineland silkgrass
  Pityopsis falcata (Pursh) Nutt. -- accepted -- sickleleaf silkgrass
  Pityopsis flexuosa (Nash) Small -- accepted -- zigzag silkgrass
  Pityopsis graminifolia (Michx.) Nutt. -- accepted -- narrowleaf silkgrass
  Pityopsis graminifolia var. aequilifolia Semple & F.D. Bowers -- accepted -- narrowleaf silkgrass
  Pityopsis graminifolia var. graminifolia (Michx.) Nutt. -- accepted -- narrowleaf silkgrass
  Pityopsis graminifolia var. latifolia (Fernald) Semple & F.D. Bowers -- accepted -- narrowleaf silkgrass
  Pityopsis graminifolia var. microcephala (Small) Semple -- not accepted
  Pityopsis graminifolia var. tenuifolia (Torr.) Semple & F.D. Bowers -- accepted -- narrowleaf silkgrass, grassleaf goldaster
  Pityopsis graminifolia var. tracyi (Small) Semple -- accepted -- Tracy's silkgrass
  Pityopsis microcephala (Small) Small -- not accepted
  Pityopsis oligantha (Chapm. ex Torr. & A. Gray) Small -- accepted -- grassleaf goldaster
  Pityopsis pinifolia (Elliot) Nutt. -- accepted -- Taylor County goldaster
  Pityopsis ruthii (Small) Small -- accepted -- Ruth's goldaster, Ruth's golden aster
  Pityopsis tracyi (Small) Small -- not accepted
  Plateilema (A. Gray) Cockerell -- accepted
  Plateilema palmeri (A. Gray) Cockerell -- accepted
  Platyschkuhria Rydb. -- accepted -- basindaisy, platyschkuhria
  Platyschkuhria integrifolia (A. Gray) Rydb. -- accepted -- basindaisy, desert basindaisy, oblongleaf basindaisy, basin daisy, oblongleaf bahia
  Platyschkuhria integrifolia var. desertorum (M.E. Jones) W. Ellison -- not accepted -- desert basindaisy
  Platyschkuhria integrifolia var. integrifolia (A. Gray) Rydb. -- not accepted -- basindaisy
  Platyschkuhria integrifolia var. oblongifolia (A. Gray) W. Ellison -- not accepted -- basin daisy, oblongleaf basindaisy, basindaisy
  Platyschkuhria integrifolia var. ourolepis (S.F. Blake) W. Ellison -- not accepted -- basindaisy
  Platyschkuhria oblongifolia (A. Gray) Rydb. -- not accepted
  Plectocephalus D. Don -- accepted
  Plectocephalus americanus (Nutt.) D. Don -- accepted -- American star-thistle
  Plectocephalus rothrockii (Greenm.) D.J.N. Hind -- accepted -- Rothrock's knapweed
  Pleiacanthus Rydb. -- accepted
  Pleiacanthus spinosus (Nutt.) Rydb. -- accepted -- thorn skeletonweed
  Pleurocoronis King & H. Rob. -- accepted -- pleurocoronis
  Pleurocoronis laphamioides (Rose) R.M. King & H. Rob. -- accepted
  Pleurocoronis pluriseta (A. Gray) King & H. Rob. -- accepted -- bush arrowleaf, arrowleaf
  Pluchea Cass. -- accepted -- camphorweed, pluchea
  Pluchea baccharis (Mill.) Pruski -- accepted -- rosy camphorweed
  Pluchea camphorata (L) DC -- accepted -- camphor pluchea, camphor weed
  Pluchea carolinensis (Jacq.) G. Don -- accepted -- cure for all
  Pluchea cortesii (Kunth) DC. -- not accepted
  Pluchea foetida (L) DC -- accepted -- stinking camphorweed
  Pluchea foetida var. foetida (L) DC -- not accepted -- stinking camphorweed
  Pluchea foetida var. imbricata Kearney -- not accepted -- stinking camphorweed
  Pluchea imbricata (Kearney) Nash -- not accepted
  Pluchea indica (L.) Less. -- accepted -- Indian camphorweed, Indian fleabane, Indian pluchea
  Pluchea longifolia Nash -- accepted -- longleaf camphorweed
  Pluchea odorata auct. non (L.) Cass. -- not accepted -- sweetscent
  Pluchea odorata (L.) Cass. -- accepted -- sweetscent, marsh fleabane
  Pluchea odorata var. odorata (L.) Cass. -- accepted -- sweetscent, marsh fleabane, sweet scent
  Pluchea odorata var. succulenta (Fernald) Cronquist -- accepted -- sweetscent
  Pluchea petiolata Cass. -- not accepted
  Pluchea purpurascens (Sw.) DC. -- not accepted
  Pluchea purpurascens var. succulenta Fernald -- not accepted
  Pluchea quitoc DC. -- not accepted
  Pluchea rosea Godfrey -- not accepted -- rosy camphorweed
  Pluchea sagittalis (Lam.) Cabrera -- accepted -- wingstem camphorweed
  Pluchea salicifolia (Mill.) S.F. Blake -- accepted -- Mexican camphorweed
  Pluchea sericea (Nutt.) Coville -- accepted -- arrowweed
  Pluchea suaveolens (Vell.) Kuntze -- not accepted
  Pluchea symphytifolia auct. non Gillis -- not accepted -- cure for all
  Pluchea symphytifolia (Mill.) Gillis -- not accepted
  Pluchea tenuifolia Small -- not accepted
  Pluchea viscida (Raf.) House -- not accepted
  Pluchea X fosbergii Cooperr. & Galang -- not accepted
  Pluchea yucatanensis G.L. Nesom -- accepted -- Yucatan camphorweed
  Plummera A. Gray -- not accepted -- plummera
  Plummera ambigens S.F. Blake -- not accepted
  Plummera floribunda A. Gray -- not accepted
  Podocoma Cass. -- accepted
  Podocoma hieracifolia (Poir.) Cass. -- accepted
  Podospermum laciniatum (L) DC -- not accepted
  Polymnia L. -- accepted -- polymnia
  Polymnia canadensis L. -- accepted -- whiteflower leafcup, rayless leafcup
  Polymnia canadensis var. radiata A. Gray -- not accepted
  Polymnia cossatotensis Pittman & V.M. Bates -- accepted -- Cossatot Mountains leafcup
  Polymnia laevigata Beadle -- accepted -- Tennessee leafcup
  Polymnia radiata (A. Gray) Small -- not accepted
  Polymnia sonchifolia Poep. & Endl. -- accepted -- yacon
  Polymnia uvedalia (L.) L. -- not accepted
  Polymnia uvedalia var. densipilis S.F. Blake -- not accepted
  Polymnia uvedalia var. floridana S.F. Blake -- not accepted
  Polypappus sericeus Nutt. -- not accepted
  Polypteris callosa (Nutt.) A. Gray -- not accepted
  Polypteris hookeriana (Torr. & A. Gray) A. Gray -- not accepted
  Polypteris integrifolia Nutt. -- not accepted
  Polypteris sphacelata (Nutt. ex Torr.) Trel. -- not accepted
  Porophyllum Adans. -- accepted -- poreleaf, porophyllum
  Porophyllum caesium Greene -- not accepted
  Porophyllum gracile Benth. -- accepted -- slender poreleaf, yerba de venado
  Porophyllum greggii A. Gray -- accepted -- Gregg's poreleaf
  Porophyllum junciforme Greene -- not accepted
  Porophyllum latifolium Benth. -- not accepted
  Porophyllum leiocarpum (Urb.) Rydb. -- accepted -- yerba de peo
  Porophyllum macrocephalum DC. -- not accepted
  Porophyllum macrocephalum var. leiocarpum Urb. -- not accepted
  Porophyllum nodosum M.E. Jones -- not accepted
  Porophyllum porophyllum (L.) Kuntze -- not accepted
  Porophyllum putidum A. Nelson -- not accepted
  Porophyllum pygmaeum Keil & J. Morefield -- accepted -- dwarf poreleaf, pygmy poreleaf
  Porophyllum ruderale (Jacq.) Cass. -- accepted -- yerba porosa
  Porophyllum ruderale ssp. macrocephalum (DC.) R.R. Johnson -- accepted -- yerba porosa
  Porophyllum ruderale ssp. ruderale (Jacq.) Cass. -- accepted -- yerba porosa
  Porophyllum ruderale var. macrocephalum (DC.) Cronquist -- not accepted
  Porophyllum scoparium A. Gray -- accepted -- Trans-Pecos poreleaf, shrubby poreleaf
  Porophyllum vaseyi Greene -- not accepted
  Prenanthella Rydb. -- accepted -- prenanthella
  Prenanthella exigua (A. Gray) Rydb. -- accepted -- brightwhite, feeble prenanthella
  Prenanthes L. -- accepted -- rattlesnakeroot
  Prenanthes alata (Hook.) D. Dietr. -- accepted -- western rattlesnakeroot
  Prenanthes alata var. sagittata A. Gray -- not accepted
  Prenanthes alba L. -- accepted -- white rattlesnakeroot, white rattlesnake-root
  Prenanthes alba var. alba L. -- not accepted
  Prenanthes alba var. pallida Milstead -- not accepted
  Prenanthes altissima L. -- accepted -- tall rattlesnakeroot, rattlesnakeroot
  Prenanthes altissima var. cinnamomea Fernald -- not accepted
  Prenanthes aspera Michx. -- accepted -- rough rattlesnakeroot
  Prenanthes autumnalis Walter -- accepted -- slender rattlesnakeroot
  Prenanthes barbata (Torr. & A. Gray) Milstead -- accepted -- barbed rattlesnakeroot
  Prenanthes boottii (DC.) A. Gray -- accepted -- alpine rattlesnakeroot
  Prenanthes carrii Singhurst -- accepted
  Prenanthes crepidinea Michx. -- accepted -- nodding rattlesnakeroot
  Prenanthes cylindrica (Small) E.L. Braun -- not accepted
  Prenanthes integrifolia (Cass.) Small -- not accepted
  Prenanthes lessingii Hultén -- not accepted
  Prenanthes nana (Bigelow) Torr. -- not accepted -- dwarf rattlesnakeroot
  Prenanthes racemosa Michx. -- accepted -- purple rattlesnakeroot, purple rattlesnake-root
  Prenanthes racemosa ssp. multiflora Cronquist -- not accepted -- purple rattlesnake-root, purple rattlesnakeroot
  Prenanthes racemosa ssp. racemosa Michx. -- not accepted -- purple rattlesnakeroot
  Prenanthes racemosa ssp. racemosa var. pinnatifida A. Gray -- not accepted -- purple rattlesnakeroot
  Prenanthes racemosa ssp. racemosa var. racemosa Michx. -- not accepted -- purple rattlesnakeroot
  Prenanthes racemosa var. multiflora (Cronquist) Dorn -- not accepted
  Prenanthes racemosa var. pinnatifida A. Gray -- not accepted
  Prenanthes racemosa var. racemosa Michx. -- not accepted
  Prenanthes roanensis (Chick.) Chick. -- accepted -- Roan Mountain rattlesnakeroot
  Prenanthes sagittata (A. Gray) A. Nelson -- accepted -- arrowleaf rattlesnakeroot
  Prenanthes serpentaria Pursh -- accepted -- cankerweed
  Prenanthes serpentaria var. barbata Torr. & A. Gray -- not accepted
  Prenanthes trifoliolata (Cass.) Fernald -- accepted -- gall of the earth, dwarf rattlesnakeroot
  Prenanthes trifoliolata var. nana (Bigelow) Fernald -- not accepted
  Prenanthes virgata Michx. -- not accepted
  Prenanthes X mainensis A. Gray (pro sp.) -- accepted -- rattlesnakeroot
  Prionopsis Nutt. -- not accepted -- prionopsis
  Prionopsis ciliata (Nutt.) Nutt. -- not accepted
  Proustia Lag. -- accepted -- proustia
  Proustia krugiana Urb. -- not accepted
  Proustia vanillosma C. Wright -- not accepted -- sweet yellowcrown
  Psacalium Cass. -- accepted -- Indianbush, psacalium
  Psacalium decompositum (A. Gray) H. Rob. & Brettell -- accepted -- desert Indianbush, psacalium
  Psathyrotes A. Gray -- accepted -- turtleback, psathyrotes
  Psathyrotes annua (Nutt.) A. Gray -- accepted -- annual psathyrotes, turtleback, mealy rosettes
  Psathyrotes pilifera A. Gray -- accepted -- hairybeast turtleback, hairy-beast turtleback, hairybeast brittlestem
  Psathyrotes ramosissima (Torr.) A. Gray -- accepted -- velvet turtleback, turtleback
  Psathyrotes scaposa A. Gray -- not accepted -- naked turtleback
  Psathyrotopsis Rydb. -- accepted
  Psathyrotopsis scaposa (A. Gray) H. Rob. -- accepted -- naked turtleback
  Pseudelephantopus Rohr -- accepted -- dog's-tongue
  Pseudelephantopus spicatus (Juss. ex Aubl.) C.F. Baker -- accepted -- dog's-tongue
  Pseudelephantopus spiralis (Less.) Cronquist -- accepted -- spiral dog's-tongue
  Pseudobahia Rydb. -- accepted -- sunburst
  Pseudobahia bahiifolia (Benth.) Rydb. -- accepted -- Hartweg's golden sunburst
  Pseudobahia bahiifolia var. pinnatifida A. Gray -- not accepted
  Pseudobahia heermannii (Durand) Rydb. -- accepted -- foothill sunburst
  Pseudobahia peirsonii Munz -- accepted -- San Joaquin adobe sunburst
  Pseudoclappia Rydb. -- accepted -- false clapdaisy, pseudoclappia
  Pseudoclappia arenaria Rydb. -- accepted -- Trans-Pecos false clapdaisy
  Pseudoclappia watsonii A. Powell & B.L. Turner -- accepted -- Watson's false clapdaisy
  Pseudognaphalium Kirp. -- accepted -- cudweed, pseudognaphalium, false cudweed
  Pseudognaphalium arizonicum (A. Gray) Anderb. -- accepted -- Arizona cudweed
  Pseudognaphalium attenuatum (DC.) Anderb. -- accepted -- tapered cudweed
  Pseudognaphalium austrotexanum G.L. Nesom -- accepted -- Texas rabbit-tobacco
  Pseudognaphalium beneolens (Davidson) Anderb. -- accepted -- Wright's cudweed
  Pseudognaphalium bicolor (Bioletti) Anderb. -- not accepted -- twocolor cudweed
  Pseudognaphalium biolettii Anderb. -- accepted -- two-color rabbit-tobacco, twocolor cudweed
  Pseudognaphalium brachypterum (DC.) Anderb. -- accepted
  Pseudognaphalium californicum (DC.) Anderb. -- accepted -- ladies' tobacco
  Pseudognaphalium canescens (DC.) W.A. Weber -- accepted -- Wright's cudweed, pseudognaphalium
  Pseudognaphalium canescens ssp. beneolens (Davidson) Kartesz -- not accepted -- Wright's cudweed
  Pseudognaphalium canescens ssp. canescens (DC.) W.A. Weber -- accepted -- Wright's cudweed, cudweed, everlasting
  Pseudognaphalium canescens ssp. microcephalum (Nutt.) Kartesz -- not accepted -- Wright's cudweed
  Pseudognaphalium canescens ssp. thermale (E.E. Nelson) Kartesz -- not accepted -- Wright's cudweed
  Pseudognaphalium domingense (Lam.) Anderb. -- not accepted -- Dominican cudweed
  Pseudognaphalium elegans (Kunth) Kartesz -- accepted -- royal cudweed
  Pseudognaphalium helleri (Britton) Anderb. -- accepted -- Heller's cudweed
  Pseudognaphalium helleri ssp. helleri (Britton) Anderb. -- accepted -- Heller's cudweed
  Pseudognaphalium helleri ssp. micradenium (Weath.) Kartesz -- not accepted -- Heller's cudweed
  Pseudognaphalium jaliscense (Greenm.) Anderb. -- accepted -- Jalisco rabbit-tobacco
  Pseudognaphalium leucocephalum (A. Gray) Anderb. -- accepted -- white cudweed
  Pseudognaphalium luteoalbum (L.) Hilliard & B.L. Burtt -- accepted -- Jersey cudweed, winged cudweed
  Pseudognaphalium macounii (Greene) Kartesz -- accepted -- Macoun's cudweed
  Pseudognaphalium micradenium (Weath.) G.L. Nesom -- accepted -- Heller's cudweed
  Pseudognaphalium microcephalum (Nutt.) Anderb. -- accepted -- Wright's cudweed
  Pseudognaphalium microcephalum var. thermale (E.E. Nelson) Dorn -- not accepted
  Pseudognaphalium obtusifolium (L.) Hilliard & B.L. Burtt -- accepted -- rabbit-tobacco, rabbittobacco
  Pseudognaphalium obtusifolium ssp. obtusifolium (L.) Hilliard & B.L. Burtt -- not accepted -- rabbittobacco
  Pseudognaphalium obtusifolium ssp. praecox (Fernald) Kartesz -- not accepted -- rabbittobacco
  Pseudognaphalium obtusifolium ssp. saxicola (Fassett) Kartesz -- not accepted -- rabbittobacco
  Pseudognaphalium pringlei (A. Gray) Anderb. -- accepted -- Pringle's cudweed
  Pseudognaphalium ramosissimum (Nutt.) Anderb. -- accepted -- pink cudweed
  Pseudognaphalium roseum (Kunth) Anderb. -- accepted -- rosy cudweed
  Pseudognaphalium sandwicensium (Gaudich.) Anderb. -- accepted -- `ena`ena
  Pseudognaphalium sandwicensium ssp. hawaiiense (O. Deg. & Sherff) Kartesz -- not accepted -- `ena`ena
  Pseudognaphalium sandwicensium ssp. kilaueanum (O. Deg. & Sherff) Kartesz -- not accepted
  Pseudognaphalium sandwicensium ssp. molokaiense (O. Deg. & Sherff) Kartesz -- not accepted -- `ena`ena
  Pseudognaphalium sandwicensium ssp. sandwicensium (Gaudich.) Anderb. -- not accepted -- `ena`ena
  Pseudognaphalium sandwicensium var. hawaiiense (O. Deg. & Sherff) W.L. Wagner -- accepted -- `ena`ena
  Pseudognaphalium sandwicensium var. kilaueanum (O. Deg. & Sherff) W.L. Wagner -- accepted -- `ena`ena
  Pseudognaphalium sandwicensium var. molokaiense (O. Deg. & Sherff) W.L. Wagner -- accepted -- `ena`ena, enaena
  Pseudognaphalium sandwicensium var. sandwicensium (Gaudich.) Anderb. -- accepted -- `ena`ena
  Pseudognaphalium saxicola (Fassett) H.E. Ballard & Feller -- accepted -- rabbit-tobacco
  Pseudognaphalium stramineum (Kunth) Anderb. -- accepted -- cottonbatting plant, annual cudweed, cotton cudweed, cottonbatting cudweed
  Pseudognaphalium thermale (E.E. Nelson) G.L. Nesom -- accepted -- Wright's cudweed
  Pseudognaphalium viscosum auct. non (Kunth) W.A. Weber -- not accepted
  Pseudognaphalium viscosum (Kunth) W.A. Weber -- accepted -- winged cudweed
  Pseudogynoxys (Greenm.) Cabrera -- accepted -- pseudogynoxys
  Pseudogynoxys chenopodioides (Kunth) Cabrera -- accepted -- Mexican flamevine
  Psilactis A. Gray -- accepted -- tansyaster, psilactis
  Psilactis asteroides A. Gray -- accepted -- New Mexico tansyaster, New Mexico tansy-aster, hoary aster
  Psilactis brevilingulata Sch. Bip. ex Hemsl. -- accepted -- Trans-Pecos tansyaster
  Psilactis coulteri auct. non A. Gray -- not accepted
  Psilactis gentryi (Standl.) D. Morgan -- accepted -- Mexican tansyaster, Mexican tansy-aster
  Psilactis heterocarpa (R.L. Hartm. & M.A. Lane) D. Morgan -- accepted -- San Patricio tansyaster
  Psilactis leptos Shinners -- not accepted
  Psilactis tenuis S. Watson -- accepted -- slender tansyaster
  Psilocarphus Nutt. -- accepted -- woollyheads, woolyheads
  Psilocarphus brevissimus Nutt. -- accepted -- short woollyheads, dwarf woolyheads
  Psilocarphus brevissimus var. brevissimus Nutt. -- accepted -- short woollyheads
  Psilocarphus brevissimus var. multiflorus Cronquist -- accepted -- dwarf woollyheads
  Psilocarphus chilensis A. Gray -- accepted -- slender woollyheads
  Psilocarphus elatior (A. Gray) A. Gray -- accepted -- meadow woollyheads
  Psilocarphus oregonus Nutt. -- accepted -- Oregon woollyheads
  Psilocarphus tenellus Nutt. -- accepted -- slender woollyheads
  Psilocarphus tenellus var. globiferus (Bertero ex DC.) Morefield -- not accepted -- slender woollyheads
  Psilocarphus tenellus var. tenellus Nutt. -- not accepted -- slender woollyheads
  Psilocarphus tenellus var. tenuis (Eastw.) Cronquist -- not accepted
  Psilochenia acuminata (Nutt.) W.A. Weber -- not accepted
  Psilochenia acuminata ssp. pluriflora (Babc. & Stebbins) W.A. Weber -- not accepted
  Psilochenia atribarba (A. Heller) W.A. Weber -- not accepted
  Psilochenia bakeri (Greene) W.A. Weber -- not accepted
  Psilochenia bakeri ssp. cusickii (Eastw.) W.A. Weber -- not accepted
  Psilochenia bakeri ssp. idahoensis (Babc. & Stebbins) W.A. Weber -- not accepted
  Psilochenia intermedia (A. Gray) W.A. Weber -- not accepted
  Psilochenia modocensis (Greene) W.A. Weber -- not accepted
  Psilochenia modocensis ssp. glareosa (Piper) W.A. Weber -- not accepted
  Psilochenia modocensis ssp. rostrata (Coville) W.A. Weber -- not accepted
  Psilochenia modocensis ssp. subacaulis (Kellogg) W.A. Weber -- not accepted
  Psilochenia monticola (Coville) W.A. Weber -- not accepted
  Psilochenia occidentalis (Nutt.) Nutt. -- not accepted
  Psilochenia occidentalis ssp. conjuncta (Jeps.) W.A. Weber -- not accepted
  Psilochenia occidentalis ssp. costata (A. Gray) W.A. Weber -- not accepted
  Psilochenia pleurocarpa (A. Gray) W.A. Weber -- not accepted
  Psilochenia runcinata (James) A. Löve & D. Löve -- not accepted
  Psilochenia runcinata ssp. andersonii (A. Gray) W.A. Weber -- not accepted
  Psilochenia runcinata ssp. barberi (Greenm.) W.A. Weber -- not accepted
  Psilochenia runcinata ssp. glauca (Nutt.) W.A. Weber -- not accepted
  Psilochenia runcinata ssp. hallii (Babc. & Stebbins) W.A. Weber -- not accepted
  Psilochenia runcinata ssp. hispidulosa (Howell ex Rydb.) W.A. Weber -- not accepted
  Psilochenia runcinata ssp. imbricata (Babc. & Stebbins) W.A. Weber -- not accepted
  Psilostrophe DC. -- accepted -- paperflower
  Psilostrophe bakeri Greene -- accepted -- Baker's paperflower
  Psilostrophe cooperi (A. Gray) Greene -- accepted -- whitestem paperflower
  Psilostrophe gnaphalioides DC. -- accepted -- dudweed, cudweed paperflower
  Psilostrophe sparsiflora (A. Gray) A. Nelson -- accepted -- greenstem paperflower
  Psilostrophe tagetina (Nutt.) Greene -- accepted -- woolly paperflower, wooly paperflower
  Psilostrophe tagetina var. cerifera (A. Nelson) B.L. Turner -- not accepted -- paperflower, woolly paperflower, hairy paperflower
  Psilostrophe tagetina var. grandiflora (Rydb.) Heiser -- not accepted
  Psilostrophe tagetina var. lanata A. Nelson -- not accepted
  Psilostrophe tagetina var. tagetina (Nutt.) Greene -- not accepted -- wooly paperflower, woolly paperflower
  Psilostrophe villosa Rydb. -- accepted -- woolly paperflower
  Pterocaulon Elliot -- accepted -- blackroot, pterocaulon
  Pterocaulon alopecuroideum (Lam.) DC. -- not accepted
  Pterocaulon alopecuroidies (Lam.) DC. -- accepted -- fox-tail blackroot
  Pterocaulon pycnostachyum (Michx.) Elliot -- accepted -- dense-spike blackroot
  Pterocaulon undulatum (Walter) C. Mohr -- not accepted
  Pterocaulon virgatum (L) DC -- accepted -- wand blackroot
  Pteronia porophylla Cav. -- not accepted
  Pterophyton aristatum (Elliot) Alexander -- not accepted
  Pterophyton helianthoides (Michx.) Alexander -- not accepted
  Pterophyton heterophyllum (Chapm.) Alexander -- not accepted
  Pterophyton pauciflorum (Nutt.) Alexander -- not accepted
  Ptilocalais nutans (Hook.) Greene -- not accepted
  Ptiloria pauciflora (Torr.) Raf. -- not accepted
  Ptiloria ramosa Rydb. -- not accepted
  Pugiopappus bigelovii A. Gray -- not accepted
  Pulicaria Gaertn. -- accepted -- false fleabane
  Pulicaria arabica (L.) Cass. -- accepted -- ladies' false fleabane
  Pulicaria dysenterica (L.) Bernh. -- accepted -- meadow false fleabane
  Pulicaria hispanica (Boiss.) Boiss. -- not accepted
  Pulicaria paludosa Link -- accepted -- Spanish false fleabane
  Pyrethrum anethifolium Willd. -- not accepted
  Pyrethrum cinerariifolium Trevir. -- not accepted
  Pyrethrum majus (Desf.) Tzvelev -- not accepted
  Pyrrhopappus DC. -- accepted -- desert-chicory, desert chicory, desertchicory
  Pyrrhopappus carolinianus (Walter) DC. -- accepted -- Carolina desert-chicory, Carolina false dandelion, Carolina desert chicory, Carolina false-dandelion
  Pyrrhopappus carolinianus var. carolinianus (Walter) DC. -- not accepted -- Carolina desertchicory
  Pyrrhopappus carolinianus var. georgianus (Shinners) H.E. Ahles -- not accepted
  Pyrrhopappus geiseri Shinners -- not accepted
  Pyrrhopappus georgianus Shinners -- not accepted
  Pyrrhopappus grandiflorus (Nutt.) Nutt. -- accepted -- tuberous desert-chicory, tuberous desertchicory
  Pyrrhopappus multicaulis DC. -- not accepted
  Pyrrhopappus multicaulis var. geiseri (Shinners) Northington -- not accepted
  Pyrrhopappus multicaulis var. multicaulis DC. -- not accepted -- desertchicory
  Pyrrhopappus pauciflorus (D. Don) DC. -- accepted -- smallflower desert-chicory, desert chicory, desertchicory, manystemmed false-dandelion
  Pyrrhopappus rothrockii A. Gray -- accepted
  Pyrrhopappus scaposus DC. -- not accepted
  Pyrrocoma Hook. -- accepted -- goldenweed
  Pyrrocoma apargioides (A. Gray) Greene -- accepted -- alpineflames
  Pyrrocoma carthamoides Hook. -- accepted -- largeflower goldenweed
  Pyrrocoma carthamoides var. carthamoides Hook. -- accepted -- largeflower goldenweed
  Pyrrocoma carthamoides var. cusickii (A. Gray) Kartesz & Gandhi -- accepted -- largeflower goldenweed, narrowhead goldenweed
  Pyrrocoma carthamoides var. subsquarrosa (Greene) G. Brown & Keil -- accepted -- largeflower goldenweed
  Pyrrocoma clementis Rydb. -- accepted -- tranquil goldenweed
  Pyrrocoma clementis var. clementis Rydb. -- accepted -- tranquil goldenweed
  Pyrrocoma clementis var. villosa (Rydb.) Mayes ex G. Brown & Keil -- accepted -- tranquil goldenweed
  Pyrrocoma congesta Greene -- not accepted
  Pyrrocoma crocea (A. Gray) Greene -- accepted -- curlyhead goldenweed
  Pyrrocoma crocea var. crocea (A. Gray) Greene -- accepted -- curlyhead goldenweed
  Pyrrocoma crocea var. genuflexa (Greene) Mayes ex G. Brown & Keil -- accepted -- curlyhead goldenweed
  Pyrrocoma genuflexa Greene -- not accepted
  Pyrrocoma gossypina Greene -- not accepted
  Pyrrocoma hirta (A. Gray) Greene -- accepted -- tacky goldenweed
  Pyrrocoma hirta var. hirta (A. Gray) Greene -- accepted -- tacky goldenweed, sticky goldenweed
  Pyrrocoma hirta var. lanulosa (Greene) Mayes ex G. Brown & Keil -- accepted -- tacky goldenweed
  Pyrrocoma hirta var. sonchifolia (Greene) Kartesz & Gandhi -- accepted -- tacky goldenweed
  Pyrrocoma howellii (A. Gray) Greene -- not accepted
  Pyrrocoma insecticruris L.F. Hend. -- accepted -- wholeleaf goldenweed
  Pyrrocoma integrifolia (Porter ex A. Gray) Greene -- accepted -- many-stemmed goldenweed, entireleaf goldenweed, manysted goldenweed
  Pyrrocoma lanceolata (Hook.) Greene -- accepted -- lanceleaf goldenweed, lance-leaf goldenweed
  Pyrrocoma lanceolata var. lanceolata (Hook.) Greene -- accepted -- lanceleaf goldenweed, lance goldenweed, Intermountain goldenweed
  Pyrrocoma lanceolata var. subviscosa (Greene) Mayes ex G. Brown & Keil -- accepted -- lanceleaf goldenweed
  Pyrrocoma lanulosa Greene -- not accepted
  Pyrrocoma liatriformis Greene -- accepted -- smallhead goldenweed
  Pyrrocoma linearis (D.D. Keck) Kartesz & Gandhi -- accepted -- thinleaf goldenhead
  Pyrrocoma lucida (D.D. Keck) Kartesz & Gandhi -- accepted -- sticky goldenweed
  Pyrrocoma racemosa (Nutt.) Torr. & A. Gray -- accepted -- clustered goldenweed
  Pyrrocoma racemosa var. congesta (Greene) Mayes ex G. Brown & Keil -- accepted -- clustered goldenweed
  Pyrrocoma racemosa var. paniculata (Nutt.) Kartesz & Gandhi -- accepted -- clustered goldenweed
  Pyrrocoma racemosa var. pinetorum (D.D. Keck) Kartesz & Gandhi -- accepted -- clustered goldenweed
  Pyrrocoma racemosa var. racemosa (Nutt.) Torr. & A. Gray -- accepted -- clustered goldenweed
  Pyrrocoma racemosa var. sessiliflora (Greene) Mayes ex G. Brown & Keil -- accepted -- clustered goldenweed
  Pyrrocoma radiata Nutt. -- accepted -- ray goldenweed, Snake River goldenweed
  Pyrrocoma sessiliflora Greene -- not accepted
  Pyrrocoma sonchifolia Greene -- not accepted
  Pyrrocoma subsquarrosa Greene -- not accepted
  Pyrrocoma subviscosa Greene -- not accepted
  Pyrrocoma uniflora (Hook.) Greene -- accepted -- plantain goldenweed
  Pyrrocoma uniflora var. gossypina (Greene) Kartesz & Gandhi -- accepted -- plantain goldenweed
  Pyrrocoma uniflora var. uniflora (Hook.) Greene -- accepted -- plantain goldenweed, singlehead goldenweed
  Pyrrocoma villosa Rydb. -- not accepted
  Rafinesquia Nutt. -- accepted -- plumeseed, California chicory, chicory
  Rafinesquia californica Nutt. -- accepted -- California plumeseed, California chicory
  Rafinesquia neomexicana A. Gray -- accepted -- New Mexico plumeseed, desert chicory
  Raillardella (A. Gray) Benth. -- accepted -- raillardella, silvermat
  Raillardella argentea (A. Gray) A. Gray -- accepted -- silky raillardella, silvermat
  Raillardella minima Rydb. -- not accepted
  Raillardella muirii A. Gray -- not accepted
  Raillardella pringlei Greene -- accepted -- showy raillardella
  Raillardella scabrida Eastw. -- not accepted
  Raillardella scaposa (A. Gray) A. Gray -- accepted -- stem raillardella, greenleaf silvermat
  Raillardia argentea A. Gray -- not accepted
  Raillardiopsis Rydb. -- not accepted -- raillardiopsis
  Raillardiopsis muirii (A. Gray) Rydb. -- not accepted -- Muir's raillardiopsis
  Raillardiopsis scabrida (Eastw.) Rydb. -- not accepted -- leafy raillardiopsis
  Railliardia arborea A. Gray -- not accepted
  Railliardia ciliolata DC. -- not accepted
  Railliardia ciliolata var. juniperoides A. Gray -- not accepted
  Railliardia ciliolata var. leptocephala O. Deg. & Sherff -- not accepted
  Railliardia ciliolata var. trinervia (Hillebr.) D.D. Keck -- not accepted
  Railliardia demissifolia Sherff -- not accepted
  Railliardia demissifolia var. dolichophylla H. St. John -- not accepted
  Railliardia herbstobatae (G.D. Carr) H. St. John -- not accepted
  Railliardia hillebrandii H. Mann -- not accepted
  Railliardia kohalae Skottsb. -- not accepted
  Railliardia latifolia A. Gray -- not accepted
  Railliardia latifolia var. helleri Sherff -- not accepted
  Railliardia linearis Gaudich. -- not accepted
  Railliardia linearis var. opposita Sherff -- not accepted
  Railliardia lonchophylla var. stipitata (Sherff) Sherff -- not accepted
  Railliardia menziesii A. Gray -- not accepted
  Railliardia menziesii var. angustifolia Sherff -- not accepted
  Railliardia molokaiensis Hillebr. -- not accepted
  Railliardia molokaiensis var. oppositifolia Sherff -- not accepted
  Railliardia molokaiensis var. stipitata Sherff -- not accepted
  Railliardia montana H. Mann -- not accepted
  Railliardia montana var. longifolia Sherff -- not accepted
  Railliardia montana var. robustior Sherff -- not accepted
  Railliardia platyphylla A. Gray -- not accepted
  Railliardia platyphylla var. leptophylla Sherff -- not accepted
  Railliardia platyphylla var. trillioidea O. Deg. & Sherff -- not accepted
  Railliardia reticulata Sherff -- not accepted
  Railliardia rockii Sherff -- not accepted
  Railliardia scabra var. leiophylla A. Gray -- not accepted
  Railliardia scabra var. munroi Sherff -- not accepted
  Railliardia sherffiana (Fosberg) Sherff -- not accepted
  Railliardia sherffiana var. paucinervia O. Deg. & Sherff -- not accepted
  Railliardia struthioloides A. Gray -- not accepted
  Railliardia ternifolia Sherff -- not accepted
  Railliardia thyrsiflora Sherff -- not accepted
  Railliardia thyrsiflora var. cernua Sherff -- not accepted
  Railliardia waianapanapaenis (G.D. Carr) H. St. John -- not accepted
  Railliardia X dolosa O. Deg. & Sherff -- not accepted
  Railliautia Sherff -- not accepted
  Railliautia X fallax (Sherff) Sherff -- not accepted
  Railliautia X fucosa (Sherff) Sherff -- not accepted
  Rainiera Greene -- accepted -- rainiera
  Rainiera stricta (Greene) Greene -- accepted -- false silverback
  Ratibida Raf. -- accepted -- prairie coneflower
  Ratibida columnaris (Pursh) D. Don -- not accepted
  Ratibida columnaris var. pulcherrima (DC.) D. Don -- not accepted
  Ratibida columnifera (Nutt.) Woot. & Standl. -- accepted -- upright prairie coneflower, prairie coneflower, redspike Mexican hat
  Ratibida peduncularis (Torr. & A. Gray) Barnhart -- accepted -- naked Mexicanhat, naked prairie coneflower
  Ratibida peduncularis var. peduncularis (Torr. & A. Gray) Barnhart -- accepted -- naked Mexicanhat
  Ratibida peduncularis var. picta (A. Gray) Sharp -- accepted -- naked Mexicanhat
  Ratibida picta (A. Gray) Small -- not accepted
  Ratibida pinnata (Vent.) Barnhart -- accepted -- pinnate prairie coneflower, grayhead prairieconeflower
  Ratibida tagetes (James) Barnhart -- accepted -- green prairie coneflower, green Mexican-hat, shortray prairieconeflower, shortray prairie coneflower
  Rayjacksonia R.L. Hartm. & M.A. Lane -- accepted -- tansyaster
  Rayjacksonia annua (Rydb.) R.L. Hartm. & M.A. Lane -- accepted -- viscid tansyaster
  Rayjacksonia aurea (A. Gray) R.L. Hartm. & M.A. Lane -- accepted -- Houston tansyaster
  Rayjacksonia phyllocephala (DC.) R.L. Hartm. & M.A. Lane -- accepted -- camphor daisy
  Reichardia Roth -- accepted -- brighteyes
  Reichardia picroides (L.) Roth -- accepted -- common brighteyes
  Reichardia tingitana (L.) Roth -- accepted -- false sowthistle
  Remya Hillebr. ex Benth. -- accepted -- remya
  Remya kauaiensis Hillebr. -- accepted -- Kauai remya
  Remya kauaiensis var. magnifica O. Deg. & Sherff -- not accepted
  Remya kauaiensis var. magnifolia O. Deg. & Sherff -- not accepted
  Remya mauiensis Hillebr. -- accepted -- Maui remya
  Remya montgomeryi W.L. Wagner & D.R. Herbst -- accepted -- Kalalau Valley remya
  Rhagadiolus Juss. -- accepted -- rhagadiolus
  Rhagadiolus edulis Gaertn. -- not accepted
  Rhagadiolus stellatus (L.) Gaertn. -- accepted -- endive daisy
  Rhaponticum Vaill. -- accepted
  Rhaponticum repens (L.) Hidalgo -- accepted -- hardheads
  Rhodanthe Lindl. -- accepted
  Rhodanthe chlorocephala (Turcz.) P. Wilson -- accepted -- rosy sunray
  Rhodanthe chlorocephala ssp. chlorocephala (Turcz.) P. Wilson -- accepted
  Rhodanthe chlorocephala ssp. rosea (Hook.) P. Wilson -- accepted
  Ridan alternifolia (L.) Britton -- not accepted
  Ridan paniculata (Walter) Small -- not accepted
  Riddellia cooperi A. Gray -- not accepted
  Riddellia tagetina (Nutt.) Greene -- not accepted
  Riddellia tagetina var. sparsiflora A. Gray -- not accepted
  Rigiopappus A. Gray -- accepted -- rigiopappus
  Rigiopappus leptocladus A. Gray -- accepted -- wireweed
  Rolandra Rottb. -- accepted -- yerba de plata
  Rolandra fruticosa (L.) Kuntze -- accepted -- yerba de plata
  Roldana Llave ex Lex. -- accepted -- groundsel
  Roldana carlomasonii (B.L. Turner & T.M. Barkley) C. Jeffrey -- not accepted
  Roldana hartwegii (Benth.) H. Rob. & Brettell -- accepted -- Hartweg's groundsel
  Roldana petasitis (Sims) H. Rob. & Brettell -- accepted -- velvet groundsel, California geranium
  Rudbeckia L. -- accepted -- coneflower
  Rudbeckia acuminata C.L. Boynt. & Beadle -- not accepted
  Rudbeckia alismifolia Torr. & A. Gray -- not accepted
  Rudbeckia alpicola Piper -- accepted -- showy coneflower
  Rudbeckia ampla A. Nelson -- not accepted
  Rudbeckia amplectens T.V. Moore -- not accepted
  Rudbeckia amplexicaulis Vahl -- accepted -- clasping coneflower
  Rudbeckia auriculata (Perdue) Kral -- accepted -- eared coneflower
  Rudbeckia beadlei Small -- not accepted
  Rudbeckia bicolor Nutt. -- not accepted -- pinewoods coneflower
  Rudbeckia brittonii Small -- not accepted
  Rudbeckia californica A. Gray -- accepted -- California coneflower
  Rudbeckia californica var. californica A. Gray -- not accepted -- California coneflower
  Rudbeckia californica var. glauca S.F. Blake -- not accepted
  Rudbeckia californica var. intermedia Perdue -- not accepted
  Rudbeckia chapmanii C.L. Boynt. & Beadle -- not accepted
  Rudbeckia columnaris Pursh non Sims -- not accepted
  Rudbeckia columnaris Sims -- not accepted
  Rudbeckia columnifera Nutt. -- not accepted
  Rudbeckia deamii S.F. Blake -- not accepted
  Rudbeckia divergens T.V. Moore -- not accepted
  Rudbeckia floridana T.V. Moore -- not accepted
  Rudbeckia floridana var. angustifolia T.V. Moore -- not accepted
  Rudbeckia foliosa C.L. Boynt. & Beadle -- not accepted
  Rudbeckia fulgida Aiton -- accepted -- orange coneflower
  Rudbeckia fulgida var. auriculata Perdue -- not accepted
  Rudbeckia fulgida var. deamii (S.F. Blake) Perdue -- accepted -- Deam's coneflower
  Rudbeckia fulgida var. fulgida Aiton -- accepted -- orange coneflower
  Rudbeckia fulgida var. missouriensis (Engelm. ex C.L. Boynt. & Beadle) Cronquist -- not accepted
  Rudbeckia fulgida var. palustris (Eggert ex C.L. Boynt. & Beadle) Perdue -- accepted -- prairie coneflower, orange coneflower
  Rudbeckia fulgida var. spathulata (Michx.) Perdue -- accepted -- orange coneflower
  Rudbeckia fulgida var. speciosa (Wender.) Perdue -- accepted -- orange coneflower
  Rudbeckia fulgida var. sullivantii (C.L. Boynt. & Beadle) Cronquist -- accepted -- Sullivant's coneflower
  Rudbeckia fulgida var. umbrosa (C.L. Boynt. & Beadle) Cronquist -- accepted -- orange coneflower
  Rudbeckia glabra DC. -- not accepted
  Rudbeckia glaucescens Eastw. -- accepted -- waxy coneflower
  Rudbeckia globosa Nutt. -- not accepted
  Rudbeckia gloriosa hort. -- not accepted
  Rudbeckia graminifolia (Torr. & A. Gray) C.L. Boynt. & Beadle -- accepted -- grassleaf coneflower
  Rudbeckia grandiflora (D. Don) J.F. Gmel. ex DC. -- accepted -- rough coneflower
  Rudbeckia grandiflora var. alismifolia (Torr. & A. Gray) Cronquist -- accepted -- rough coneflower
  Rudbeckia grandiflora var. grandiflora (D. Don) J.F. Gmel. ex DC. -- accepted -- rough coneflower
  Rudbeckia heliopsidis Torr. & A. Gray -- accepted -- sunfacing coneflower
  Rudbeckia heterophylla Torr. & A. Gray -- not accepted
  Rudbeckia hirta L. -- accepted -- blackeyed Susan, black-eyed Susan
  Rudbeckia hirta var. angustifolia (T.V. Moore) Perdue -- accepted -- blackeyed Susan
  Rudbeckia hirta var. brittonii (Small) Fernald -- not accepted
  Rudbeckia hirta var. corymbifera Fernald -- not accepted
  Rudbeckia hirta var. floridana (T.V. Moore) Perdue -- accepted -- blackeyed Susan
  Rudbeckia hirta var. hirta L. -- accepted -- blackeyed Susan
  Rudbeckia hirta var. lanceolata (Bisch.) Core -- not accepted
  Rudbeckia hirta var. monticola (Small) Fernald -- not accepted
  Rudbeckia hirta var. pulcherrima Farw. -- accepted -- blackeyed Susan, pinewoods coneflower
  Rudbeckia hirta var. sericea (T.V. Moore) Fernald -- not accepted
  Rudbeckia hirta var. serotina (Nutt.) Core -- not accepted
  Rudbeckia klamathensis P. Cox & Urbatsch -- accepted -- Klamath coneflower
  Rudbeckia laciniata L. -- accepted -- cutleaf coneflower, green-head coneflower
  Rudbeckia laciniata ssp. ampla (A. Nelson) W.A. Weber -- not accepted
  Rudbeckia laciniata var. ampla (A. Nelson) Cronquist -- accepted -- cutleaf coneflower, green-head coneflower
  Rudbeckia laciniata var. bipinnata Perdue -- accepted -- cutleaf coneflower
  Rudbeckia laciniata var. digitata (Mill.) Fiori -- not accepted -- cutleaf coneflower
  Rudbeckia laciniata var. heterophylla (Torr. & A. Gray) Fernald & B.G. Schub. -- accepted
  Rudbeckia laciniata var. hortensis L.H. Bailey -- not accepted
  Rudbeckia laciniata var. humilis A. Gray -- accepted -- greenhead coneflower, cutleaf coneflower
  Rudbeckia laciniata var. laciniata L. -- accepted -- cutleaf coneflower
  Rudbeckia longipes T.V. Moore -- not accepted
  Rudbeckia maxima Nutt. -- accepted -- great coneflower
  Rudbeckia missouriensis Engelm. ex C.L. Boynt. & Beadle -- accepted -- Missouri orange coneflower, Missouri coneflower
  Rudbeckia mohrii A. Gray -- accepted -- Mohr's coneflower
  Rudbeckia mollis Elliot -- accepted -- softhair coneflower
  Rudbeckia montana A. Gray -- accepted -- montane coneflower
  Rudbeckia monticola Small -- not accepted
  Rudbeckia nitida Nutt. -- accepted -- shiny coneflower
  Rudbeckia nitida var. texana Perdue -- not accepted
  Rudbeckia occidentalis Nutt. -- accepted -- western coneflower
  Rudbeckia occidentalis var. alpicola (Piper) Cronquist -- not accepted
  Rudbeckia occidentalis var. montana (A. Gray) Perdue -- not accepted
  Rudbeckia occidentalis var. occidentalis Nutt. -- not accepted -- western coneflower
  Rudbeckia pallida Nutt. -- not accepted
  Rudbeckia palustris Eggert ex C.L. Boynt. & Beadle -- not accepted
  Rudbeckia pinnata Vent. -- not accepted
  Rudbeckia pinnatiloba (Torr. & A. Gray) Beadle -- not accepted
  Rudbeckia purpurea L. -- not accepted
  Rudbeckia rupestris Chick. -- not accepted
  Rudbeckia scabrifolia L.E. Brown -- accepted -- roughleaf coneflower
  Rudbeckia sericea T.V. Moore -- not accepted
  Rudbeckia serotina Nutt. -- not accepted
  Rudbeckia serotina var. corymbifera (Fernald) Fernald & B.G. Schub. -- not accepted
  Rudbeckia serotina var. lanceolata (Bisch.) Fernald & B.G. Schub. -- not accepted
  Rudbeckia serotina var. sericea (T.V. Moore) Fernald & B.G. Schub. -- not accepted
  Rudbeckia spathulata Michx. -- not accepted
  Rudbeckia speciosa Wender. -- not accepted
  Rudbeckia speciosa var. sullivantii (C.L. Boynt. & Beadle) B.L. Rob. -- not accepted
  Rudbeckia subtomentosa Pursh -- accepted -- sweet coneflower
  Rudbeckia sullivantii C.L. Boynt. & Beadle -- not accepted
  Rudbeckia tagetes James -- not accepted
  Rudbeckia tenax C.L. Boynt. & Beadle -- not accepted
  Rudbeckia texana (Perdue) P. Cox & Urbatsch -- accepted -- Texas coneflower, Rudbeckia texana
  Rudbeckia triloba L. -- accepted -- browneyed Susan
  Rudbeckia triloba var. beadlei (Small) Fernald -- not accepted
  Rudbeckia triloba var. pinnatiloba Torr. & A. Gray -- accepted -- browneyed Susan
  Rudbeckia triloba var. rupestris (Chick.) A. Gray -- accepted -- browneyed Susan
  Rudbeckia triloba var. triloba L. -- accepted -- browneyed Susan
  Rudbeckia truncata Small -- not accepted
  Rudbeckia umbrosa C.L. Boynt. & Beadle -- not accepted
  Rugelia Shuttlw. ex Chapm. -- accepted -- Rugel's Indianplantain
  Rugelia nudicaulis Shuttlw. ex Chapm. -- accepted -- Rugel's Indianplantain
  Rydbergia brandegeei (Porter ex A. Gray) Rydb. -- not accepted
  Rydbergia grandiflora (Torr. & A. Gray ex A. Gray) Greene -- not accepted
  Sachsia Griseb. -- accepted -- sachsia
  Sachsia bahamensis Urb. -- not accepted
  Sachsia polycephala Griseb. -- accepted -- Bahama sachsia
  Salmea DC. -- accepted -- bejuco de miel
  Salmea scandens (L) DC -- accepted -- bejuco de miel
  Santolina L. -- accepted -- lavender cotton
  Santolina chamaecyparissus L. -- accepted -- lavender cotton
  Santolina neapolitana Jord. & Fourr. -- accepted
  Santolina rosmarinifolia L. -- accepted
  Santolina suaveolens Pursh -- not accepted
  Santolina virens Mill. -- not accepted
  Sanvitalia Lam. -- accepted -- creeping zinnia, sanvitalia
  Sanvitalia abertii A. Gray -- accepted -- Albert's creeping zinnia
  Sanvitalia angustifolia A. Gray -- not accepted
  Sanvitalia ocymoides DC. -- accepted -- yellow creeping zinnia
  Sanvitalia procumbens Lam. -- accepted -- Mexican creeping zinnia
  Sartwellia A. Gray -- accepted -- glowwort, sartwellia
  Sartwellia flaveriae A. Gray -- accepted -- threadleaf glowwort
  Sartwellia gypsophila Powell & B.L. Turner -- accepted -- gypsum glowwort
  Sartwellia puberula Rydb. -- not accepted
  Saussurea DC. -- accepted -- saw-wort
  Saussurea alpina (L) DC -- not accepted -- alpine sawwort
  Saussurea amara (L) DC -- accepted -- saussurea
  Saussurea amara var. amara (L) DC -- accepted
  Saussurea amara var. glomerata (Poir.) Trautv. -- accepted
  Saussurea americana D.C. Eaton -- accepted -- American saw-wort
  Saussurea angustifolia (Willd.) DC. -- accepted -- narrowleaf saw-wort
  Saussurea angustifolia ssp. yukonensis (A.E. Porsild) Cody -- not accepted
  Saussurea angustifolia var. angustifolia (Willd.) DC. -- accepted -- narrowleaf saw-wort
  Saussurea angustifolia var. viscida (Hultén) S.L. Welsh -- accepted -- sticky saw-wort
  Saussurea angustifolia var. yukonensis A.E. Porsild -- accepted -- narrowleaf saw-wort
  Saussurea densa (Hook.) Rydb. -- not accepted -- clustered sawwort
  Saussurea glomerata Poir. -- not accepted
  Saussurea nuda Ledeb. -- accepted -- nutty saw-wort, clustered sawwort
  Saussurea nuda ssp. densa (Hook.) G.W. Douglas -- not accepted
  Saussurea nuda var. densa (Hook.) Hultén -- not accepted
  Saussurea tilesii (Ledeb.) Ledeb. -- accepted -- Tiles' saussurea
  Saussurea triangulata Trautv. & C.A. Meyer -- accepted
  Saussurea viscida Hultén -- not accepted -- sticky saw-wort
  Saussurea viscida var. yukonensis (A.E. Porsild) Hultén -- not accepted
  Saussurea weberi Hultén -- accepted -- Weber's saw-wort
  Saussurea X tschuktschorum Lipsch. (pro sp.) -- accepted -- Tschuktsch's saussurea
  Scabrethia W.A. Weber -- accepted
  Scabrethia scabra (Hook.) W.A. Weber -- accepted -- badlands mule-ears
  Scabrethia scabra ssp. attenuata (W.A. Weber) W.A. Weber -- accepted -- badlands mule-ears
  Scabrethia scabra ssp. canescens (W.A. Weber) W.A. Weber -- accepted -- badlands mule-ears
  Scabrethia scabra ssp. scabra (Hook.) W.A. Weber -- accepted -- badlands mule-ears
  Schkuhria Roth -- accepted -- false threadleaf
  Schkuhria anthemoidea (DC.) J.M. Coult. -- not accepted -- Wright's false threadleaf
  Schkuhria anthemoidea var. anthemoidea (DC.) J.M. Coult. -- not accepted -- Wright's false threadleaf
  Schkuhria anthemoidea var. wrightii (A. Gray) Heiser -- not accepted -- Wright's false threadleaf
  Schkuhria multiflora Hook. & Arn. -- accepted -- manyflower false threadleaf, many-flower false threadleaf
  Schkuhria multiflora var. multiflora Hook. & Arn. -- not accepted
  Schkuhria pinnata (Lam.) Kuntze ex Thell. -- accepted -- pinnate false threadleaf, Wright's false threadleaf, Wislizenus' false threadleaf
  Schkuhria pinnata var. guatemalensis (Rydb.) McVaugh -- not accepted
  Schkuhria pinnata var. pinnata (Lam.) Kuntze ex Thell. -- not accepted -- pinnate false threadleaf
  Schkuhria pinnata var. wislizeni (A. Gray) B.L. Turner -- not accepted -- Wislizenus' false threadleaf
  Schkuhria wislizeni A. Gray -- not accepted -- Wislizenus' false threadleaf
  Schkuhria wislizeni var. frustrata S.F. Blake -- not accepted -- Wislizenus' false threadleaf
  Schkuhria wislizeni var. wislizeni A. Gray -- not accepted -- Wislizenus' false threadleaf
  Schkuhria wislizeni var. wrightii (A. Gray) S.F. Blake -- not accepted
  Sclerocarpus Jacq. -- accepted -- bonebract, sclerocarpus
  Sclerocarpus africanus Jacq. -- accepted -- African bonebract
  Sclerocarpus uniserialis (Benth.) Hemsl. -- accepted -- Mexican bonebract
  Sclerocarpus uniserialis var. austrotexanus B.L. Turner -- not accepted -- Mexican bonebract
  Sclerocarpus uniserialis var. uniserialis (Benth.) Hemsl. -- not accepted -- Mexican bonebract
  Sclerolepis Cass. -- accepted -- bogbutton
  Sclerolepis uniflora (Walter) Britton, Sterns & Poggenb. -- accepted -- pink bogbutton
  Scolymus L. -- accepted -- goldenthistle
  Scolymus grandiflorus Desf. -- not accepted
  Scolymus hispanicus L. -- accepted -- common goldenthistle, golden thistle
  Scolymus maculatus L. -- accepted -- spotted goldenthistle
  Scorzonella Nutt. -- not accepted
  Scorzonella laciniata (Hook.) Sch. Bip. -- not accepted
  Scorzonella laciniata var. bolanderi (A. Gray) Jeps. -- not accepted
  Scorzonella laciniata var. pratensis (Greene) Jeps. -- not accepted
  Scorzonella leachiana M. Peck -- not accepted
  Scorzonella leptosepala Nutt. -- not accepted
  Scorzonella nutans Hook. -- not accepted
  Scorzonella nutans var. major (A. Gray) M. Peck -- not accepted
  Scorzonella procera Greene -- not accepted
  Scorzonella troximoides (A. Gray) Jeps. -- not accepted
  Scorzonera L. -- accepted -- scorzonera
  Scorzonera hispanica L. -- accepted -- black salsify
  Scorzonera laciniata L. -- accepted -- cutleaf vipergrass
  Selloa glutinosa Spreng. -- not accepted
  Senecio L. -- accepted -- ragwort, groundsel
  Senecio actinella Greene -- accepted -- Flagstaff ragwort
  Senecio actinella var. mogollonicus (Greene) Greenm. -- not accepted
  Senecio acutidens Rydb. -- not accepted
  Senecio adamsii Howell -- not accepted
  Senecio admirabilis Greene -- not accepted
  Senecio alabamensis Britton ex Small -- not accepted
  Senecio alaskanus Hultén -- not accepted
  Senecio ambrosioides Rydb. -- not accepted
  Senecio amplectens A. Gray -- accepted -- showy alpine ragwort, showy alpine groundsel, alpine groundsel
  Senecio amplectens var. amplectens A. Gray -- accepted -- showy alpine ragwort
  Senecio amplectens var. holmii (Greene) H.D. Harr. -- accepted -- Holm's ragwort, Holm's groundsel
  Senecio amplectens var. taraxacoides A. Gray -- not accepted
  Senecio ampullaceus Hook. -- accepted -- Texas ragwort
  Senecio anonymus Alph. Wood -- not accepted -- Small's ragwort
  Senecio antennariifolius Britton -- not accepted -- shalebarren ragwort
  Senecio anteuphorbium (L.) Sch. Bip. -- not accepted
  Senecio aphanactis Greene -- accepted -- chaparral ragwort
  Senecio aquaticus Hill -- not accepted
  Senecio aquaticus ssp. barbareifolius (Wimm. & Grab.) S.M. Walters -- not accepted
  Senecio argutus A. Rich. -- not accepted
  Senecio arizonicus Greene -- accepted -- Arizona ragwort
  Senecio aronicoides DC. -- accepted -- rayless ragwort
  Senecio astephanus Greene -- accepted -- San Gabriel ragwort
  Senecio atratus Greene -- accepted -- tall blacktip ragwort
  Senecio atropurpureus (Ledeb.) Fedtsch. -- not accepted -- arctic senecio
  Senecio atropurpureus ssp. frigidus (Richardson) Hultén -- not accepted
  Senecio atropurpureus ssp. tomentosus (Kjellm.) Hultén -- not accepted
  Senecio atropurpureus var. dentatus (A. Gray) Hultén -- not accepted
  Senecio atropurpureus var. ulmeri (Steffen) A.E. Porsild -- not accepted
  Senecio aureus L. -- not accepted -- golden ragwort
  Senecio aureus var. aquilonius Fernald -- not accepted
  Senecio aureus var. borealis Torr. & A. Gray -- not accepted
  Senecio aureus var. gracilis (Pursh) Hook. -- not accepted
  Senecio aureus var. intercursus Fernald -- not accepted
  Senecio aureus var. semicordatus (Mack. & Bush) Greenm. -- not accepted
  Senecio aureus var. werneriifolius A. Gray -- not accepted
  Senecio balsamitae Muhl. ex Willd. -- not accepted
  Senecio bernardinus Greene -- not accepted -- San Bernardino ragwort
  Senecio bicolor (Willd.) Todaro -- not accepted -- silver ragwort
  Senecio bicolor ssp. cineraria (DC.) Chater -- not accepted -- silver ragwort
  Senecio bigelovii A. Gray -- accepted -- nodding ragwort
  Senecio bigelovii var. bigelovii A. Gray -- accepted -- nodding ragwort, Bigelow ragwort, Bigelow's ragwort
  Senecio bigelovii var. hallii A. Gray -- accepted -- Hall's ragwort
  Senecio bivestitus Cronquist -- not accepted
  Senecio blitoides Greene -- not accepted
  Senecio blochmaniae Greene -- accepted -- dune ragwort
  Senecio bolanderi A. Gray -- not accepted -- Bolander's ragwort
  Senecio bolanderi var. bolanderi A. Gray -- not accepted -- Bolander's ragwort
  Senecio bolanderi var. harfordii (Greenm.) T.M. Barkley -- not accepted -- Harford's ragwort
  Senecio breweri Burtt Davy -- not accepted -- Brewer's ragwort
  Senecio cacalioides Fisch. ex Spreng. -- not accepted
  Senecio californicus DC. -- accepted -- California ragwort
  Senecio cannabifolius Less. -- not accepted -- Aleutian ragwort
  Senecio cannabinifolius Hook. & Arn. -- accepted -- hempleaf ragwort
  Senecio canus Hook. -- not accepted -- woolly groundsel
  Senecio capillaris Gaudich. -- not accepted
  Senecio cardamine Greene -- not accepted -- bittercress ragwort
  Senecio carlomasonii B.L. Turner & T.M. Barkley -- not accepted -- Carl Mason's ragwort
  Senecio carthamoides Greene -- not accepted
  Senecio castoreus S.L. Welsh -- not accepted
  Senecio cernuus A. Gray non L. f. -- not accepted
  Senecio cineraria DC. -- not accepted
  Senecio clarkianus A. Gray -- accepted -- Clark's ragwort
  Senecio clevelandii Greene -- not accepted -- Cleveland's ragwort
  Senecio clevelandii var. heterophyllus Hoover -- not accepted
  Senecio clivorum Maxim. -- not accepted -- summer ragwort
  Senecio columbianus Greene -- not accepted
  Senecio confusus Britten -- not accepted
  Senecio congestus (R. Br.) DC. -- not accepted -- marsh fleabane, clustered marsh ragwort
  Senecio congestus ssp. tonsus (Fernald) Á. Löve & D. Löve -- not accepted
  Senecio congestus var. palustris (L.) Fernald -- not accepted
  Senecio congestus var. tonsus Fernald -- not accepted
  Senecio conterminus Greenm. -- not accepted -- senecio
  Senecio convallium Greenm. -- not accepted
  Senecio covillei Greene -- not accepted
  Senecio covillei var. scorzonella (Greene) Jeps. -- not accepted
  Senecio crassulus A. Gray -- accepted -- thickleaf ragwort, thickleaf groundsel, meadow groundsel
  Senecio crassulus var. cusickii (Piper) Greenm. -- not accepted
  Senecio crawfordii Britton -- not accepted
  Senecio crepidineus Greene -- not accepted
  Senecio crocatus Rydb. -- not accepted -- saffron ragwort
  Senecio crocatus var. wolfii Greenm. -- not accepted
  Senecio cruentus DC. -- not accepted
  Senecio cymbalaria Pursh -- not accepted -- dwarf arctic ragwort, dwarf arctic groundsel, séneçon fausse-cymbalaire
  Senecio cymbalarioides Nutt. non Senecio cymbalarioides H. Buek -- not accepted -- cleftleaf groundsel
  Senecio cymbalarioides H. Buek -- not accepted
  Senecio cymbalarioides ssp. moresbiensis Calder & Roy L. Taylor -- not accepted
  Senecio cymbalarioides var. borealis (Torr. & A. Gray) Greenm. -- not accepted
  Senecio cymbalarioides var. suksdorfii (Greenm.) M. Peck -- not accepted
  Senecio cynthioides Greene -- not accepted -- White Mountain ragwort
  Senecio debilis Nutt. -- not accepted -- weak groundsel
  Senecio densus Greene -- not accepted
  Senecio dimorphophyllus Greene -- not accepted -- splitleaf groundsel
  Senecio dimorphophyllus var. dimorphophyllus Greene -- not accepted -- splitleaf groundsel
  Senecio dimorphophyllus var. intermedius T.M. Barkley -- not accepted -- splitleaf groundsel
  Senecio dimorphophyllus var. paysonii T.M. Barkley -- not accepted -- Payson's groundsel
  Senecio discoideus (Hook.) Britton -- not accepted
  Senecio douglasii DC. -- not accepted
  Senecio douglasii ssp. longilobus (Benth.) W.A. Weber -- not accepted
  Senecio douglasii var. jamesii (Torr. & A. Gray) Ediger ex Correll & M.C. Johnst. -- not accepted
  Senecio douglasii var. longilobus (Benth.) L.D. Benson -- not accepted
  Senecio douglasii var. monoensis (Greene) Jeps. -- not accepted
  Senecio douglasii var. tularensis Munz -- not accepted
  Senecio elegans L. -- accepted -- redpurple ragwort
  Senecio elmeri Piper -- accepted -- Elmer's ragwort
  Senecio eremophilus Richardson -- accepted -- desert ragwort, desert groundsel
  Senecio eremophilus ssp. kingii (Rydb.) G.W. Douglas & G. Ruyle-Douglas -- not accepted
  Senecio eremophilus ssp. macdougalii (A. Heller) G.W. Douglas & G. Ruyle-Douglas -- not accepted
  Senecio eremophilus var. eremophilus Richardson -- accepted -- desert ragwort
  Senecio eremophilus var. kingii (Rydb.) Greenm. -- accepted -- King's ragwort, King's groundsel, ragwort groundsel
  Senecio eremophilus var. macdougalii (A. Heller) Cronquist -- accepted -- MacDougal's ragwort, MacDougal's groundsel
  Senecio erraticus Bertol. -- not accepted
  Senecio ertterae T.M. Barkley -- accepted -- Ertter's ragwort
  Senecio erucifolius L. -- not accepted -- hoary ragwort
  Senecio eurycephalus Torr. & A. Gray -- not accepted -- widehead groundsel
  Senecio eurycephalus var. eurycephalus Torr. & A. Gray -- not accepted -- Siskiyou ragwort
  Senecio eurycephalus var. lewisrosei (J.T. Howell) T.M. Barkley -- not accepted -- Lewis' groundsel
  Senecio eurypterus Greenm. -- not accepted
  Senecio exaltatus Nutt. -- not accepted
  Senecio fedifolius Rydb. -- not accepted
  Senecio fendleri A. Gray -- not accepted -- Fendler's ragwort
  Senecio fendleri var. lanatus Osterh. -- not accepted
  Senecio filifolius Nutt. non P.J. Bergius -- not accepted
  Senecio flaccidus Less. -- accepted -- threadleaf ragwort, threadleaf groundsel
  Senecio flaccidus var. douglasii (DC.) B.L. Turner & T.M. Barkley -- accepted -- Douglas' ragwort, Douglas' senecio, Douglas' groundsel
  Senecio flaccidus var. flaccidus Less. -- accepted -- threadleaf ragwort, threadleaf groundsel
  Senecio flaccidus var. monoensis (Greene) B.L. Turner & T.M. Barkley -- accepted -- Mono ragwort, green groundsel, Mono groundsel
  Senecio flavulus Greene -- not accepted
  Senecio flettii Wiegand -- not accepted -- Flett's ragwort
  Senecio flocciferus DC. -- not accepted
  Senecio foetidus J.T. Howell -- not accepted
  Senecio foetidus var. hydrophiloides (Rydb.) T.M. Barkley ex Cronquist -- not accepted
  Senecio franciscanus Greene -- not accepted -- San Francisco Peaks ragwort, San Francisco Peaks groundsel
  Senecio fremontii Torr. & A. Gray -- accepted -- dwarf mountain ragwort, Fremont's groundsel
  Senecio fremontii ssp. blitoides (Greene) W.A. Weber -- not accepted
  Senecio fremontii ssp. occidentalis (A. Gray) G.W. Douglas & G. Ruyle-Douglas -- not accepted
  Senecio fremontii var. blitoides (Greene) Cronquist -- accepted -- dwarf mountain ragwort
  Senecio fremontii var. fremontii Torr. & A. Gray -- accepted -- dwarf mountain ragwort
  Senecio fremontii var. inexpectatus Cronquist -- accepted -- dwarf mountain ragwort
  Senecio fremontii var. occidentalis A. Gray -- accepted -- dwarf mountain ragwort, western groundsel
  Senecio frigidus (Richardson) Less. -- not accepted
  Senecio fulgens Rydb. -- not accepted
  Senecio fuscatus auct. non Hayek -- not accepted -- fuscatus groundsel
  Senecio ganderi T.M. Barkley & R.M. Beauch. -- not accepted -- Gander's ragwort
  Senecio gaspensis Greenm. -- not accepted
  Senecio gaspensis var. firmifolius (Greenm.) Fernald -- not accepted
  Senecio gibbsonsii Greene -- not accepted
  Senecio glabellus Poir. -- not accepted -- butterweed, cressleaf, cressleaf groundsel
  Senecio glaucifolius Rydb. -- not accepted
  Senecio glomeratus Desf. ex Poir. -- accepted -- cutleaf burnweed
  Senecio gracilis Pursh -- not accepted
  Senecio grandifolius Less. -- not accepted
  Senecio greenei A. Gray -- not accepted -- flame ragwort
  Senecio greggii Rydb. -- not accepted
  Senecio hallii Britton -- not accepted
  Senecio hallii var. discoidea W.A. Weber -- not accepted
  Senecio harbourii Rydb. -- not accepted
  Senecio harfordii Greenm. -- not accepted
  Senecio hartianus A. Heller -- not accepted -- Hart's ragwort
  Senecio hartwegii Benth. -- not accepted
  Senecio hesperius Greene -- not accepted -- western ragwort
  Senecio heterodoxus Greene ex Rydb. -- not accepted
  Senecio hieraciifolius L. -- not accepted
  Senecio holmii Greene -- not accepted
  Senecio hookeri Torr. & A. Gray -- not accepted
  Senecio howellii Greene -- not accepted
  Senecio huachucanus A. Gray -- not accepted
  Senecio hybridus (Willd.) Regel -- not accepted
  Senecio hydrophiloides Rydb. -- accepted -- tall groundsel
  Senecio hydrophilus Nutt. -- accepted -- water ragwort, water groundsel, alkali marsh groundsel
  Senecio hyperborealis Greenm. -- not accepted -- northern groundsel
  Senecio imparipinnatus Klatt -- not accepted
  Senecio indecorus Greene -- not accepted -- elegant groundsel
  Senecio integerrimus Nutt. -- accepted -- lambstongue ragwort, lamb-tongue ragwort, lambstongue groundsel
  Senecio integerrimus var. exaltatus (Nutt.) Cronquist -- accepted -- Columbia ragwort, Columbia groundsel
  Senecio integerrimus var. integerrimus Nutt. -- accepted -- lambstongue ragwort
  Senecio integerrimus var. lugens (Richardson) B. Boivin -- not accepted
  Senecio integerrimus var. major (A. Gray) Cronquist -- accepted -- lambstongue ragwort, lambstongue groundsel
  Senecio integerrimus var. ochroleucus (A. Gray) Cronquist -- accepted -- paleyellow ragwort
  Senecio integerrimus var. scribneri (Rydb.) T.M. Barkley -- accepted -- Scribner's ragwort
  Senecio integerrimus var. vaseyi (Greenm.) Cronquist -- not accepted
  Senecio integrifolius (L.) Clairv. -- not accepted
  Senecio ionophyllus Greene -- not accepted -- Tehachapi ragwort
  Senecio ionophyllus var. sparsilobatus (Parish) H.M. Hall -- not accepted
  Senecio jacobaea L. -- not accepted -- stinking willie, tansy ragwort, ragwort
  Senecio jonesii Rydb. -- not accepted
  Senecio kingii Rydb. -- not accepted
  Senecio kjellmanii A.E. Porsild -- not accepted
  Senecio laetiflorus Greene -- not accepted
  Senecio layneae Greene -- not accepted -- Layne's ragwort, Layne's butterweed
  Senecio lemmonii A. Gray -- accepted -- Lemmon's ragwort, Lemmon's groundsel
  Senecio leonardii Rydb. -- not accepted
  Senecio lewisrosei J.T. Howell -- not accepted
  Senecio ligulifolius Greene -- not accepted
  Senecio lindstroemii (Ostenf.) A.E. Porsild -- not accepted
  Senecio lobatus Pers. -- not accepted
  Senecio longilobus Benth. -- not accepted
  Senecio longipetiolatus Rydb. -- not accepted
  Senecio lugens Richardson -- accepted -- small blacktip ragwort
  Senecio lugens var. exaltatus (Nutt.) A. Gray -- not accepted
  Senecio lugens var. ochroleucus A. Gray -- not accepted
  Senecio lynceus Greene -- not accepted
  Senecio lynceus var. leucoreus (Greenm.) S.F. Blake -- not accepted
  Senecio lyonii A. Gray -- accepted -- island senecio
  Senecio macdougalii A. Heller -- not accepted
  Senecio macounii Greene -- not accepted -- Siskiyou Mountain ragwort
  Senecio madagascariensis Poir. -- accepted -- Madagascar ragwort, fireweed, Madagascar groundsel
  Senecio magnificus F. Muell. -- accepted -- tall yellowtop
  Senecio malmstenii S.F. Blake ex Tidestr. -- not accepted
  Senecio mandraliscae (Tineo) H. Jacobsen -- not accepted
  Senecio manitobensis Greenm. -- not accepted
  Senecio megacephalus Nutt. -- accepted -- rocky ragwort
  Senecio memmingeri Britton -- not accepted
  Senecio metcalfei Greene -- not accepted
  Senecio mikanioides Otto -- not accepted -- Cape-ivy, capeivy
  Senecio millefolium Torr. & A. Gray -- not accepted -- piedmont ragwort
  Senecio millelobatus Rydb. -- not accepted -- Uinta ragwort
  Senecio minimus Poir. -- not accepted
  Senecio mohavensis A. Gray -- accepted -- Mojave ragwort, Mohave groundsel
  Senecio molinarius Greenm. -- not accepted
  Senecio monoensis Greene -- not accepted
  Senecio moresbiensis (Calder & Roy L. Taylor) G.W. Douglas & G. Ruyle-Douglas -- not accepted -- cleftleaf ragwort
  Senecio muehlenbergii Sch. Bip. -- not accepted
  Senecio muirii Greenm. -- not accepted
  Senecio multicapitatus Greenm. ex Rydb. -- not accepted
  Senecio multidentatus Sch. Bip. ex Hemsl. -- accepted -- Huachuca Mountain ragwort
  Senecio multidentatus var. huachucanus (A. Gray) T.M. Barkley -- accepted -- Huachuca Mountain ragwort
  Senecio multidentatus var. multidentatus Sch. Bip. ex Hemsl. -- accepted
  Senecio multilobatus Torr. & A. Gray ex A. Gray -- not accepted -- lobeleaf groundsel
  Senecio murrayi Bornm. -- not accepted
  Senecio musiniensis S.L. Welsh -- not accepted -- Musinea ragwort
  Senecio mutabilis Greene -- not accepted
  Senecio neomexicanus A. Gray -- not accepted -- New Mexico groundsel
  Senecio neomexicanus var. griffithsii Greenm. -- not accepted
  Senecio neomexicanus var. metcalfei (Greene) T.M. Barkley -- not accepted -- Metcalf's groundsel
  Senecio neomexicanus var. mutabilis (Greene) T.M. Barkley -- not accepted -- New Mexico groundsel
  Senecio neomexicanus var. neomexicanus Gray -- not accepted -- New Mexico groundsel
  Senecio neomexicanus var. toumeyi (Greene) T.M. Barkley -- not accepted -- Toumey's groundsel
  Senecio neowebsteri S.F. Blake -- accepted -- Olympic Mountain ragwort
  Senecio newcombei Greene -- not accepted -- Newcombe's ragwort
  Senecio obovatus Muhl. ex Willd. -- not accepted -- roundleaf ragwort, round-leaf groundsel, séneçon ŕ feuilles obovales
  Senecio obovatus var. elliottii (Torr. & A. Gray) Fernald -- not accepted
  Senecio obovatus var. rotundus Britton -- not accepted
  Senecio ogotorukensis Packer -- not accepted -- Ogotoruk Creek ragwort
  Senecio oodes Rydb. -- not accepted
  Senecio oresbius Greenm. -- not accepted
  Senecio palmensis (Nees) C. Sm. ex Link -- not accepted
  Senecio palustris (L.) Hook. -- not accepted
  Senecio pammelii Greenm. -- not accepted
  Senecio parryi A. Gray -- accepted -- mountain ragwort, Parry's groundsel
  Senecio pattersonensis Hoover -- accepted -- Patterson's senecio, Mono groundsel
  Senecio pauciflorus Pursh -- not accepted -- alpine groundsel
  Senecio pauciflorus var. fallax (Greenm.) Greenm. -- not accepted
  Senecio pauciflorus var. jucundulus Jeps. -- not accepted
  Senecio pauperculus Michx. -- not accepted -- balsam groundsel
  Senecio pauperculus var. balsamitae (Muhl. ex Willd.) Fernald -- not accepted
  Senecio pauperculus var. crawfordii (Britton) T.M. Barkley -- not accepted
  Senecio pauperculus var. firmifolius (Greenm.) Greenm. -- not accepted
  Senecio pauperculus var. neoscoticus Fernald -- not accepted
  Senecio pauperculus var. praelongus (Greenm.) House -- not accepted
  Senecio pauperculus var. thompsoniensis (Greenm.) B. Boivin -- not accepted
  Senecio pereziifolius Rydb. -- not accepted
  Senecio petasitis (Sims) DC. -- not accepted
  Senecio plattensis Nutt. -- not accepted -- prairie groundsel
  Senecio platylobus Rydb. -- not accepted
  Senecio porteri Greene -- not accepted -- Porter's groundsel
  Senecio pseudaureus Rydb. -- not accepted -- falsegold groundsel
  Senecio pseudaureus ssp. flavulus (Greene) G.W. Douglas & G. Ruyle-Douglas -- not accepted
  Senecio pseudaureus ssp. semicordatus (Mack. & Bush) G.W. Douglas & G. Ruyle-Douglas -- not accepted
  Senecio pseudaureus var. flavulus (Greene) Greenm. -- not accepted -- falsegold groundsel
  Senecio pseudaureus var. pseudaureus Rydb. -- not accepted -- falsegold groundsel
  Senecio pseudaureus var. semicordatus (Mack. & Bush) T.M. Barkley -- not accepted -- falsegold groundsel
  Senecio pseudoarnica Less. -- accepted -- seaside ragwort
  Senecio pseudotomentosus Mack. & Bush -- not accepted
  Senecio pudicus Greene -- accepted -- bashful ragwort
  Senecio purshianus Nutt. -- not accepted
  Senecio quaerens Greene -- not accepted -- Mogollon Mountain ragwort
  Senecio quaylei T.M. Barkley -- accepted -- Quayle's ragwort
  Senecio quercetorum Greene -- not accepted -- Oak Creek ragwort
  Senecio rapifolius Nutt. -- accepted -- openwoods ragwort
  Senecio resedifolius Less. -- not accepted
  Senecio riddellii Torr. & A. Gray -- accepted -- Riddell's ragwort, Riddell's groundsel, sand groundsel
  Senecio robbinsii Oakes ex Rusby -- not accepted
  Senecio rotundus (Britton) Small -- not accepted
  Senecio rubricaulis Greene -- not accepted
  Senecio rugelia A. Gray -- not accepted
  Senecio rupestris Waldst. & Kit. -- accepted -- rock ragwort
  Senecio sacramentanus Woot. & Standl. -- accepted -- Sacramento ragwort
  Senecio salignus DC. -- not accepted -- willow ragwort
  Senecio sandvicensis auct. non Less. -- not accepted
  Senecio sandwicensis auct. non Less. -- not accepted
  Senecio sanguisorboides Rydb. -- not accepted -- burnet ragwort
  Senecio saxosus Klatt -- not accepted
  Senecio saxosus var. toiyabensis Greenm. -- not accepted
  Senecio schweinitzianus Nutt. -- not accepted -- Schweinitz's ragwort
  Senecio scorzonella Greene -- accepted -- Sierra ragwort, Sierra groundsel
  Senecio scribneri Rydb. -- not accepted
  Senecio seemanii auct. non Sch. Bip. ex Seem. -- not accepted
  Senecio semicordatus Mack. & Bush -- not accepted
  Senecio serra Hook. -- accepted -- tall ragwort, butterweed groundsel, butterweed
  Senecio serra var. admirabilis (Greene) A. Nelson -- accepted -- tall ragwort
  Senecio serra var. altior Jeps. -- not accepted
  Senecio serra var. integriusculus A. Gray -- not accepted
  Senecio serra var. serra Hook. -- accepted -- tall ragwort, tall groundsel
  Senecio sheldonensis A.E. Porsild -- accepted -- Mt. Sheldon ragwort
  Senecio smallii Britton -- not accepted
  Senecio soldanella A. Gray -- accepted -- Colorado ragwort
  Senecio spartioides Torr. & A. Gray -- accepted -- broom-like ragwort, broom groundsel, broomlike ragwort
  Senecio spartioides var. fremontii (Torr. & A. Gray) Greenm. -- not accepted
  Senecio spartioides var. granularis Maguire & A.H. Holmgren ex Cronquist -- not accepted
  Senecio spartioides var. multicapitatus (Greenm. ex Rydb.) S.L. Welsh -- not accepted -- broom-like ragwort, many-head ragwort, ragwort groundsel
  Senecio spartioides var. parksii (Cory) Shinners -- not accepted
  Senecio spartioides var. spartioides Torr. & A. Gray -- not accepted -- broom-like ragwort
  Senecio spellenbergii T.M. Barkley -- not accepted -- Carrizo Creek ragwort
  Senecio sphaerocephalus Greene -- accepted -- ballhead ragwort, marsh groundsel
  Senecio spribillei W.A. Weber -- accepted
  Senecio squalidus L. -- accepted -- Oxford ragwort
  Senecio streptanthifolius Greene -- not accepted -- cleftleaf groundsel
  Senecio streptanthifolius var. borealis (Torr. & A. Gray) J.F. Bain -- not accepted -- Rocky Mountain groundsel
  Senecio streptanthifolius var. kluanei J.F. Bain -- not accepted -- Kluane's senecio
  Senecio streptanthifolius var. laetiflorus (Greene) J.F. Bain -- not accepted -- Rocky Mountain groundsel
  Senecio streptanthifolius var. moresbiensis (Calder & Roy L. Taylor) B. Boivin -- not accepted
  Senecio streptanthifolius var. oodes (Rydb.) J.F. Bain -- not accepted -- Rocky Mountain groundsel
  Senecio streptanthifolius var. rubricaulis (Greene) J.F. Bain -- not accepted -- Rocky Mountain groundsel
  Senecio streptanthifolius var. streptanthifolius Greene -- not accepted -- cleftleaf groundsel
  Senecio streptanthifolius var. wallowensis J.F. Bain -- not accepted -- Wallowa senecio
  Senecio stygius Greene -- not accepted
  Senecio suaveolens (L.) Ell. -- accepted -- false Indian plantain
  Senecio subcuneatus Rydb. -- not accepted
  Senecio subnudus DC. -- not accepted
  Senecio suksdorfii Greenm. -- not accepted
  Senecio sylvaticus L. -- accepted -- woodland ragwort
  Senecio tampicanus DC. -- not accepted -- Great Plains ragwort
  Senecio taraxacoides (A. Gray) Greene -- accepted -- dandelion ragwort
  Senecio thornberi Greenm. -- not accepted
  Senecio thurberi A. Gray -- not accepted
  Senecio tichomirovii auct. non Schischkin -- not accepted
  Senecio toiyabensis S.L. Welsh & Goodrich -- not accepted
  Senecio tomentosus Michx. -- not accepted -- woolly ragwort
  Senecio toumeyi Greene -- not accepted
  Senecio triangularis Hook. -- accepted -- arrowleaf ragwort, arrowleaf groundsel
  Senecio triangularis var. angustifolius G.N. Jones -- not accepted
  Senecio tridenticulatus Rydb. -- not accepted -- threetooth ragwort
  Senecio tundricola auct. non Tolm. -- not accepted
  Senecio tweedyi Rydb. -- not accepted
  Senecio uintahensis (A. Nelson) Greenm. -- not accepted
  Senecio valerianifolius Link ex Spreng. -- not accepted
  Senecio vaseyi Greenm. -- not accepted
  Senecio viscosus L. -- accepted -- sticky ragwort
  Senecio vulgaris L. -- accepted -- old-man-in-the-spring, common groundsel
  Senecio wardii Greene -- not accepted
  Senecio warnockii Shinners -- accepted -- Warnock's ragwort
  Senecio webbii (Sch. Bip.) Christ -- not accepted
  Senecio websteri Greenm. non Hook. f. -- not accepted
  Senecio werneriifolius (A. Gray) A. Gray -- not accepted -- hoary groundsel
  Senecio werneriifolius var. alpinus (A. Gray) Dorn -- not accepted
  Senecio werneriifolius var. incertus Greenm. -- not accepted
  Senecio wootonii Greene -- accepted -- Wooton's ragwort
  Senecio wrightii Greenm. -- not accepted
  Senecio X hybridus (Willd.) Regel -- not accepted -- common ragwort, florist's cineraria
  Senecio yukonensis A.E. Porsild -- not accepted -- Yukon groundsel
  Senecioides cinerea (L.) Kuntze ex Britton & P. Wilson -- not accepted
  Sericocarpus Greene -- accepted -- whitetop aster
  Sericocarpus acutisquamosus (Nash) Small -- not accepted
  Sericocarpus asteroides (L.) Britton, Sterns & Poggenb. -- accepted -- toothed whitetop aster
  Sericocarpus bifoliatus (Walter) Porter -- not accepted
  Sericocarpus californicus Durand -- not accepted
  Sericocarpus linifolius (L.) Britton, Sterns & Poggenb. -- accepted -- narrowleaf whitetop aster
  Sericocarpus oregonensis Nutt. -- accepted -- Oregon whitetop aster
  Sericocarpus oregonensis ssp. californicus (Durand) Ferris -- accepted -- Oregon whitetop aster
  Sericocarpus oregonensis ssp. oregonensis Nutt. -- accepted -- Oregon whitetop aster
  Sericocarpus oregonensis var. californicus (Durand) G.L. Nesom -- not accepted -- Oregon whitetop aster
  Sericocarpus oregonensis var. oregonensis Nutt. -- not accepted -- Oregon whitetop aster
  Sericocarpus rigidus Lindl. -- accepted -- Columbian whitetop aster
  Sericocarpus tomentellus Greene -- not accepted
  Sericocarpus tortifolius (Michx.) Nees -- accepted -- Dixie whitetop aster
  Serinia oppositifolia (Raf.) Kuntze -- not accepted
  Seriphidium arbusculum (Nutt.) W.A. Weber -- not accepted
  Seriphidium arbusculum ssp. longilobum (Osterh.) W.A. Weber -- not accepted
  Seriphidium canum (Pursh) W.A. Weber -- not accepted
  Seriphidium canum ssp. bolanderi (A. Gray) W.A. Weber -- not accepted
  Seriphidium canum ssp. viscidulum (Osterh.) W.A. Weber -- not accepted
  Seriphidium novum (A. Nelson) W.A. Weber -- not accepted
  Seriphidium pygmaeum (A. Gray) W.A. Weber -- not accepted
  Seriphidium rigidum (Nutt.) W.A. Weber -- not accepted
  Seriphidium rothrockii (A. Gray) W.A. Weber -- not accepted
  Seriphidium tridentatum (Nutt.) W.A. Weber -- not accepted
  Seriphidium tridentatum ssp. parishii (A. Gray) W.A. Weber -- not accepted
  Seriphidium tridentatum ssp. vaseyanum (Rydb.) W.A. Weber -- not accepted
  Seriphidium tridentatum ssp. wyomingense (Beetle & Young) W.A. Weber -- not accepted
  Seriphidium tripartitum (Rydb.) W.A. Weber -- not accepted
  Seriphidium vaseyanum (Rydb.) W.A. Weber -- not accepted
  Serratula L. -- accepted -- plumeless saw-wort
  Serratula alpina L. -- not accepted
  Serratula arvensis L. -- not accepted
  Serratula tinctoria L. -- accepted -- Dyer's plumeless saw-wort
  Shinnersia R.M.King & H. Rob. -- accepted
  Shinnersia rivularis (A. Gray) King & H. Rob. -- accepted -- Rio Grande bugheal
  Shinnersoseris S. Tomb -- accepted -- beaked skeletonweed, shinnersoseris
  Shinnersoseris rostrata (A. Gray) S. Tomb -- accepted -- beaked skeletonweed, beaked-skeleton-weed
  Sideranthus annuus Rydb. -- not accepted
  Sideranthus aureus (A. Gray) Small -- not accepted
  Sideranthus australis (Greene) Rydb. -- not accepted
  Sideranthus cotula Small -- not accepted
  Sideranthus glaberrimus Rydb. -- not accepted
  Sideranthus gooddingii A. Nelson -- not accepted
  Sideranthus gracilis (Nutt.) A. Nelson -- not accepted
  Sideranthus grindelioides (Nutt.) Britton -- not accepted
  Sideranthus laevis Woot. & Standl. -- not accepted
  Sideranthus machaerantherus Small -- not accepted
  Sideranthus megacephalus (Nash) Small -- not accepted
  Sideranthus puberulus Rydb. -- not accepted
  Sideranthus spinulosus (Pursh) Sweet ex Rydb. -- not accepted
  Sideranthus spinulosus var. glaberrimus (Rydb.) A. Nelson -- not accepted
  Sideranthus turbinellus Rydb. -- not accepted
  Sideranthus wootonii (Greene) Standl. -- not accepted
  Sigesbeckia L. -- accepted -- St. Paul's wort
  Sigesbeckia jorullensis Kunth -- accepted
  Sigesbeckia laciniata Poir. -- not accepted
  Sigesbeckia orientalis L. -- accepted -- common St. Paul's wort
  Silphium L. -- accepted -- rosinweed
  Silphium albiflorum A. Gray -- accepted -- white rosinweed
  Silphium angustum (A. Gray) Small -- not accepted
  Silphium asperrimum Hook. -- not accepted
  Silphium asteriscus L. -- accepted -- starry rosinweed
  Silphium asteriscus ssp. trifoliatum (L.) Weber & Fisher -- not accepted
  Silphium asteriscus var. angustatum A. Gray -- not accepted -- starry rosinweed
  Silphium asteriscus var. asteriscus L. -- accepted -- starry rosinweed, roughleaf rosinweed
  Silphium asteriscus var. dentatum (Elliott) Chapm. -- accepted -- starry rosinweed
  Silphium asteriscus var. laevicaule DC. -- not accepted -- starry rosinweed
  Silphium asteriscus var. latifolium (A. Gray) J.A. Clevinger -- accepted -- whorled rosinweed
  Silphium asteriscus var. scabrum Nutt. -- not accepted
  Silphium asteriscus var. simpsonii (Greene) J.A. Clevinger -- accepted -- Simpson's rosinweed
  Silphium asteriscus var. trifoliatum (L.) J.A. Clevinger -- accepted -- whorled rosinweed
  Silphium atropurpureum Retz. ex Willd. -- not accepted
  Silphium brachiatum Gattinger -- accepted -- Cumberland rosinweed
  Silphium chickamaugense Canby -- not accepted
  Silphium compositum Michx. -- accepted -- kidneyleaf rosinweed
  Silphium compositum ssp. ovatifolium (Torr. & A. Gray) Sweeny & T.R. Fisher -- not accepted
  Silphium compositum ssp. reniforme (Raf. ex Nutt.) Sweeny & T.R. Fisher -- not accepted
  Silphium compositum ssp. venosum (Small) Sweeny & T.R. Fisher -- not accepted
  Silphium compositum var. compositum Michx. -- not accepted -- kidneyleaf rosinweed
  Silphium compositum var. ovatifolium Torr. & A. Gray -- not accepted -- kidneyleaf rosinweed
  Silphium compositum var. reniforme (Raf. ex Nutt.) Torr. & A. Gray -- not accepted -- kidneyleaf rosinweed
  Silphium compositum var. venosum (Small) Kartesz & Gandhi -- not accepted -- kidneyleaf rosinweed
  Silphium confertifolium Small -- not accepted
  Silphium connatum L. -- not accepted
  Silphium dentatum Elliott -- not accepted
  Silphium dentatum var. angustatum (A. Gray) L.M. Perry -- not accepted
  Silphium dentatum var. gatesii (C. Mohr) H.E. Ahles -- not accepted
  Silphium elliottii Small -- not accepted
  Silphium gatesii C. Mohr -- not accepted
  Silphium glabrum Eggert ex Small -- not accepted
  Silphium glutinosum J. Allison -- accepted -- sticky rosinweed
  Silphium gracile A. Gray -- not accepted -- slender rosinweed
  Silphium incisum Greene -- not accepted
  Silphium integrifolium Michx. -- accepted -- wholeleaf rosinweed
  Silphium integrifolium var. asperrimum (Hook.) B.L. Turner -- not accepted
  Silphium integrifolium var. deamii L.M. Perry -- not accepted -- Deam's rosinweed
  Silphium integrifolium var. gattingeri L.M. Perry -- not accepted -- Gattinger's rosinweed
  Silphium integrifolium var. integrifolium Michx. -- accepted -- wholeleaf rosinweed
  Silphium integrifolium var. laeve Torr. & A. Gray -- accepted -- wholeleaf rosinweed
  Silphium integrifolium var. neglectum Settle & T.R. Fisher -- not accepted -- wholeleaf rosinweed
  Silphium laciniatum L. -- accepted -- compassplant, compass plant
  Silphium laciniatum var. laciniatum L. -- not accepted -- compassplant
  Silphium laciniatum var. robinsonii L.M. Perry -- not accepted -- Robinson's compassplant
  Silphium laevigatum Elliot non Pursh -- not accepted
  Silphium laevigatum Pursh -- not accepted
  Silphium lapsuum Small -- not accepted
  Silphium mohrii Small -- accepted -- Mohr's rosinweed
  Silphium nodum Small -- not accepted
  Silphium orae Small -- not accepted
  Silphium ovatifolium (Torr. & A. Gray) Small -- not accepted
  Silphium perfoliatum L. -- accepted -- cup plant, cup-plant, cupleaf rosinweed, squarestem rosinweed
  Silphium perfoliatum ssp. connatum (L.) Cruden -- not accepted
  Silphium perfoliatum var. connatum (L.) Cronquist -- accepted -- cup plant
  Silphium perfoliatum var. perfoliatum L. -- accepted -- cup plant
  Silphium perplexum J. Allison -- accepted -- Old Cahaba rosinweed
  Silphium pinnatifidum Elliot -- not accepted -- tansy rosinweed
  Silphium radula Nutt. -- accepted -- roughstem rosinweed, starry rosinweed
  Silphium radula var. gracile (A. Gray) J.A. Clevinger -- accepted -- slender rosinweed
  Silphium radula var. radula Nutt. -- accepted -- Reverchon's rosinweed
  Silphium reniforme Raf. ex Nutt. -- not accepted
  Silphium reverchonii Bush -- not accepted -- Reverchon's rosinweed
  Silphium rumicifolium Small -- not accepted
  Silphium scaberrimum Elliot -- not accepted -- roughleaf rosinweed
  Silphium scabrum Moench non Walter -- not accepted
  Silphium simpsonii Greene -- not accepted -- Simpson's rosinweed
  Silphium simpsonii var. wrightii L.M. Perry -- not accepted
  Silphium speciosum Nutt. -- not accepted
  Silphium terebinthinaceum Elliot non Jacq. -- not accepted -- prairie rosinweed
  Silphium terebinthinaceum Jacq. -- accepted -- prairie rosinweed
  Silphium terebinthinaceum var. luciae-brauniae Steyerm. -- not accepted -- Lucy Braun's rosinweed
  Silphium terebinthinaceum var. pinnatifidum (Elliot) A. Gray -- accepted -- tansy rosinweed
  Silphium terebinthinaceum var. terebinthinaceum Jacq. -- accepted -- prairie rosinweed
  Silphium trifoliatum L. -- accepted -- whorled rosinweed
  Silphium trifoliatum var. latifolium A. Gray -- not accepted -- whorled rosinweed
  Silphium trifoliatum var. trifoliatum L. -- not accepted -- whorled rosinweed
  Silphium trilobatum L. -- not accepted
  Silphium venosum Small -- not accepted
  Silphium wasiotense M. Medley -- accepted -- Appalachian rosinweed
  Silybum Adans. -- accepted -- milkthistle, milk thistle
  Silybum eburneum Coss. & Durieu -- accepted
  Silybum marianum (L.) Gaertn. -- accepted -- blessed milkthistle, blessed milk-thistle, spotted thistle, variegated thistle, milk thistle
  Simsia Pers. -- accepted -- bush sunflower
  Simsia calva (Engelm. & A. Gray) A. Gray -- accepted -- awnless bushsunflower
  Simsia exaristata A. Gray -- not accepted
  Simsia exaristata var. perplexa S.F. Blake -- not accepted
  Simsia frutescens A. Gray -- not accepted
  Simsia lagasceiformis DC. -- accepted -- annual bushsunflower, annual bush sunflower
  Simsia scaposa A. Gray -- not accepted
  Sinosenecio B. Nord. -- accepted -- butterweed
  Sinosenecio newcombei (Greene) J.P. Janovec & T.M. Barkley -- accepted -- Newcombe's butterweed
  Sitilias caroliniana (Walter) Raf. -- not accepted
  Sitilias grandiflora (Nutt.) Greene -- not accepted
  Sitilias multicaulis (DC.) Greene -- not accepted
  Smallanthus Mack. ex Small -- accepted -- smallanthus
  Smallanthus uvedalia (L.) Mack. ex Small -- accepted -- hairy leafcup
  Smallanthus uvedalius (L.) Mack. ex Small -- not accepted -- hairy leafcup
  Solidago L. -- accepted -- goldenrod, verges d'or
  Solidago aestivalis E.P. Bicknell -- not accepted
  Solidago albopilosa E.L. Braun -- accepted -- whitehair goldenrod, white-haired goldenrod
  Solidago altiplanities C.E.S. Taylor & R.J. Taylor -- accepted -- high plains goldenrod
  Solidago altissima L. -- accepted -- Canada goldenrod
  Solidago altissima ssp. altissima L. -- accepted -- late goldenrod, Canada goldenrod
  Solidago altissima ssp. gilvocanescens (Rydb.) Semple -- accepted -- Great Plains late goldendrod, shorthair goldenrod
  Solidago altissima var. altissima L. -- not accepted
  Solidago altissima var. canescens (A. Gray) M.C. Johnst. -- not accepted
  Solidago altissima var. gilvocanescens (Rydb.) Semple -- not accepted
  Solidago altissima var. pluricephala M.C. Johnst. -- not accepted
  Solidago altissima var. procera (Aiton) Fernald -- not accepted
  Solidago amplexicaulis Torr. & A. Gray ex A. Gray non M. Martens -- not accepted
  Solidago angusta Torr. & A. Gray -- not accepted
  Solidago angustifolia Elliot -- not accepted
  Solidago anticostensis Fernald -- not accepted
  Solidago arenicola D.B. Keener & Kral -- accepted -- southern racemose goldenrod
  Solidago arguta Aiton -- accepted -- Atlantic goldenrod
  Solidago arguta ssp. arguta Aiton -- accepted
  Solidago arguta ssp. boottii (Hook.) G. Morton -- not accepted
  Solidago arguta ssp. caroliniana (A. Gray) G. Morton -- accepted -- Atlantic goldenrod
  Solidago arguta ssp. pseudoyadkinensis G. Morton -- not accepted
  Solidago arguta var. arguta Aiton -- accepted -- Atlantic goldenrod
  Solidago arguta var. boottii (Hook.) Palmer & Steyerm. -- accepted -- Boott's goldenrod
  Solidago arguta var. caroliniana A. Gray -- accepted -- Atlantic goldenrod
  Solidago arguta var. harrisii (Steele) Cronquist -- accepted -- Harris' goldenrod
  Solidago arguta var. neurolepis (Fernald) Steyerm. -- not accepted -- Atlantic goldenrod
  Solidago arguta var. strigosa (Small) Steyerm. -- not accepted
  Solidago arizonica (A. Gray) Woot. & Standl. -- not accepted
  Solidago aspera Aiton -- not accepted
  Solidago asteroides Semple -- not accepted
  Solidago auriculata Shuttlw. ex S.F. Blake -- accepted -- eared goldenrod
  Solidago austrina Small -- not accepted
  Solidago axillaris Pursh -- not accepted
  Solidago bartramiana Fernald -- not accepted
  Solidago bellidifolia Greene -- not accepted
  Solidago bicolor L. -- accepted -- white goldenrod
  Solidago bicolor var. concolor Torr. & A. Gray -- not accepted
  Solidago bicolor var. lanata (Hook.) Seymour -- not accepted
  Solidago bicolor var. ovalis Farw. -- not accepted
  Solidago bicolor var. tonsa (Fernald) B. Boivin -- not accepted
  Solidago bigelovii A. Gray -- not accepted
  Solidago bigelovii var. wrightii (A. Gray) A. Gray -- not accepted
  Solidago boottii Hook. -- not accepted
  Solidago boottii var. brachyphylla (Chapm. ex Torr. & A. Gray) A. Gray -- not accepted
  Solidago boottii var. caroliniana (A. Gray) Cronquist -- not accepted
  Solidago boottii var. ludoviciana A. Gray -- not accepted
  Solidago brachyphylla Chapm. ex Torr. & A. Gray -- accepted -- Dixie goldenrod
  Solidago buckleyi Torr. & A. Gray -- accepted -- Buckley's goldenrod
  Solidago caesia L. -- accepted -- wreath goldenrod
  Solidago caesia var. axillaris (Pursh) A. Gray -- not accepted
  Solidago caesia var. caesia L. -- accepted -- wreath goldenrod
  Solidago caesia var. curtisii (Torr. & A. Gray) Alph. Wood -- not accepted -- mountain decumbent goldenrod
  Solidago caesia var. hispida Alph. Wood -- not accepted
  Solidago caesia var. paniculata A. Gray -- not accepted
  Solidago caesia var. zedia R.E. Cook & Semple -- accepted
  Solidago calcicola Fernald -- not accepted -- limestone goldenrod
  Solidago californica Nutt. -- not accepted -- California goldenrod
  Solidago californica var. nevadensis A. Gray -- not accepted
  Solidago camporum (Greene) A. Nelson -- not accepted
  Solidago canadensis L. -- accepted -- Canada goldenrod, Canadian goldenrod, common goldenrod
  Solidago canadensis ssp. elongata (Nutt.) D.D. Keck -- not accepted
  Solidago canadensis ssp. salebrosa (Piper) D.D. Keck -- not accepted
  Solidago canadensis var. arizonica A. Gray -- not accepted
  Solidago canadensis var. bartramiana (Fernald) Beaudry -- not accepted -- Bartram's goldenrod
  Solidago canadensis var. canadensis L. -- accepted -- Canada goldenrod, Canadian goldenrod
  Solidago canadensis var. canescens A. Gray -- not accepted
  Solidago canadensis var. elongata (Nutt.) M. Peck -- not accepted
  Solidago canadensis var. gilvocanescens Rydb. -- not accepted -- shorthair goldenrod, Canadian goldenrod
  Solidago canadensis var. hargeri Fernald -- accepted -- Harger's goldenrod, Canadian goldenrod
  Solidago canadensis var. lepida (DC.) Cronquist -- not accepted -- Canada goldenrod
  Solidago canadensis var. rupestris (Raf.) Porter -- not accepted
  Solidago canadensis var. salebrosa (Piper) M.E. Jones -- not accepted -- salebrosa goldenrod, Canadian goldenrod
  Solidago canadensis var. scabra Torr. & A. Gray -- not accepted -- Canada goldenrod, Canadian goldenrod
  Solidago canadensis var. subserrata (DC.) Cronquist -- not accepted
  Solidago canescens (Rydb.) Friesner -- not accepted
  Solidago caroliniana (L.) Britton, Sterns & Poggenb. -- not accepted
  Solidago celtidifolia Small -- not accepted
  Solidago chapmanii A. Gray -- not accepted
  Solidago chlorolepis Fernald -- not accepted
  Solidago chrysolepis Fernald -- not accepted
  Solidago chrysothamnoides (Greene) Bush -- not accepted
  Solidago ciliosa Greene -- not accepted
  Solidago conferta Mill. -- not accepted
  Solidago confinis A. Gray -- accepted -- Nevada goldenrod
  Solidago corymbosa Elliot -- not accepted
  Solidago curtisii Torr. & A. Gray -- accepted -- mountain decumbent goldenrod
  Solidago curtisii var. curtisii Torr. & A. Gray -- accepted
  Solidago curtisii var. flaccidifolia (Small) R.E. Cook & Semple -- accepted -- mountain goldenrod
  Solidago curtisii var. pubens (M.A. Curtis) A. Gray -- not accepted
  Solidago cutleri Fernald -- not accepted -- Cutler's alpine goldenrod
  Solidago deamii Fernald -- not accepted -- Deam's goldenrod
  Solidago decemflora DC. -- not accepted
  Solidago decumbens Greene -- not accepted
  Solidago decumbens var. chlorolepis (Fernald) Beaudry -- not accepted
  Solidago decumbens var. oreophila (Rydb.) Fernald -- not accepted
  Solidago delicatula Small -- accepted -- elmleaf goldenrod
  Solidago discoidea Elliott -- not accepted -- rayless mock goldenrod
  Solidago dispersa Small -- not accepted
  Solidago drummondii Torr. & A. Gray -- accepted -- Drummond's goldenrod
  Solidago dumetorum Lunell -- not accepted -- Turtle Mountain goldenrod
  Solidago edisoniana Mack. -- not accepted
  Solidago elliottii Torr. & A. Gray -- not accepted
  Solidago elliottii var. ascendens Fernald -- not accepted
  Solidago elliottii var. edisoniana (Mack.) Fernald -- not accepted
  Solidago elliottii var. pedicellata Fernald -- not accepted
  Solidago elliptica Aiton -- not accepted
  Solidago elongata Nutt. -- accepted
  Solidago erecta Pursh -- accepted -- showy goldenrod
  Solidago farwellii Fernald -- not accepted
  Solidago faucibus Wieboldt -- accepted
  Solidago fistulosa Mill. -- accepted -- pine barren goldenrod, pinebarren goldenrod
  Solidago flaccidifolia Small -- not accepted -- mountain goldenrod
  Solidago flavovirens Chapm. -- not accepted
  Solidago flexicaulis L. -- accepted -- zigzag goldenrod
  Solidago galetorum (Greene) Friesner -- not accepted
  Solidago gattingeri Chapm. ex A. Gray -- accepted -- Gattinger's goldenrod
  Solidago gigantea Aiton -- accepted -- giant goldenrod
  Solidago gigantea ssp. serotina (Kuntze) McNeill -- not accepted
  Solidago gigantea var. leiophylla Fernald -- not accepted
  Solidago gigantea var. pitcheri (Nutt.) Shinners -- not accepted
  Solidago gigantea var. serotina (Kuntze) Cronquist -- not accepted
  Solidago gigantea var. shinnersii Beaudry -- not accepted
  Solidago gillmanii (A. Gray) Steele -- not accepted
  Solidago gilvocanescens (Rydb.) Smyth -- not accepted
  Solidago glaberrima M. Martens -- not accepted
  Solidago glaberrima var. moritura (Steele) Palmer & Steyerm. -- not accepted
  Solidago glomerata Michx. -- accepted -- clustered goldenrod
  Solidago glutinosa Nutt. -- not accepted
  Solidago glutinosa ssp. randii (Porter) Cronquist -- not accepted
  Solidago glutinosa var. chlorolepis (Fernald) G.S. Ringius -- not accepted
  Solidago glutinosa var. gillmanii (A. Gray) Cronquist -- not accepted
  Solidago glutinosa var. nana (A. Gray) Cronquist -- not accepted
  Solidago glutinosa var. ontarioensis G.S. Ringius -- not accepted
  Solidago glutinosa var. racemosa (Greene) Cronquist -- not accepted
  Solidago gracilis Poir. -- not accepted
  Solidago gracillima Torr. & A. Gray -- not accepted -- Virginia goldenrod
  Solidago graminea (Woot. & Standl.) S.F. Blake -- not accepted
  Solidago graminifolia (L.) Salisb. -- not accepted
  Solidago graminifolia var. galetorum (Greene) House -- not accepted
  Solidago graminifolia var. gymnospermoides (Greene) Croat -- not accepted
  Solidago graminifolia var. major (Michx.) Fernald -- not accepted
  Solidago graminifolia var. media (Greene) S.K. Harris -- not accepted
  Solidago graminifolia var. nuttallii (Greene) Fernald -- not accepted
  Solidago graminifolia var. polycephala (Fernald) Fernald -- not accepted
  Solidago grandiflora Raf. -- not accepted
  Solidago guiradonis A. Gray -- accepted -- Guirado goldenrod
  Solidago gymnospermoides (Greene) Fernald -- not accepted
  Solidago gymnospermoides var. callosa S.K. Harris -- not accepted
  Solidago harperi Mack. -- not accepted
  Solidago harrisii Steele -- not accepted
  Solidago helleri Small -- not accepted
  Solidago hirsutissima Mill. -- not accepted
  Solidago hirtella (Greene) Bush -- not accepted
  Solidago hispida Muhl. ex Willd. -- accepted -- hairy goldenrod
  Solidago hispida var. arnoglossa Fernald -- not accepted -- hairy goldenrod
  Solidago hispida var. hispida Muhl. ex Willd. -- not accepted -- hairy goldenrod
  Solidago hispida var. lanata (Hook.) Fernald -- not accepted -- hairy goldenrod
  Solidago hispida var. tonsa Fernald -- not accepted -- hairy goldenrod
  Solidago houghtonii Torr. & A. Gray ex A. Gray -- accepted -- Houghton's goldenrod
  Solidago howellii Woot. & Standl. -- not accepted
  Solidago jacksonii (Kuntze) Fernald -- not accepted
  Solidago jacksonii var. humilis (Porter) Beaudry -- not accepted
  Solidago jejunifolia E.S. Steele -- not accepted
  Solidago juliae G.L. Nesom -- accepted -- Julia's goldenrod
  Solidago juncea Aiton -- accepted -- early goldenrod
  Solidago juncea var. juncea Aiton -- not accepted -- early goldenrod
  Solidago juncea var. neobohemica Fernald -- not accepted
  Solidago juncea var. ramosa Porter & Britton -- not accepted
  Solidago kralii Semple -- accepted -- Kral's goldenrod
  Solidago lancifolia Torr. & A. Gray -- accepted -- lance-leaf goldenrod
  Solidago lateriflora L. -- not accepted
  Solidago latifolia L. -- not accepted
  Solidago latissimifolia Mill. -- accepted -- Elliott's goldenrod
  Solidago leavenworthii Torr. & A. Gray -- accepted -- Leavenworth's goldenrod
  Solidago leiocarpa DC. in DC. & A. DC. -- accepted -- Cutler's alpine goldenrod
  Solidago lepida DC. -- accepted -- Canada goldenrod
  Solidago lepida ssp. fallax (Fernald) Semple -- accepted
  Solidago lepida ssp. lepida DC. -- accepted
  Solidago lepida var. elongata (Nutt.) Fernald -- not accepted
  Solidago lepida var. fallax Fernald -- not accepted
  Solidago lepida var. lepida DC. -- accepted -- Canada goldenrod
  Solidago lepida var. molina Fernald -- not accepted
  Solidago lepida var. salebrosa (Piper) Semple -- accepted -- salebrosa goldenrod
  Solidago leptocephala Torr. & A. Gray -- not accepted
  Solidago lindheimeriana Scheele -- not accepted
  Solidago longipetiolata Mack. & Bush -- not accepted
  Solidago ludoviciana (A. Gray) Small -- accepted -- Louisiana goldenrod
  Solidago lunellii Rydb. -- not accepted
  Solidago macrophylla Banks ex Pursh -- accepted -- largeleaf goldenrod
  Solidago macrophylla var. thyrsoidea (E. Mey.) Fernald -- not accepted
  Solidago maxonii Pollard -- not accepted
  Solidago media (Greene) Bush -- not accepted
  Solidago mensalis Fernald -- not accepted
  Solidago mexicana L. -- not accepted
  Solidago microcephala (Greene) Bush -- not accepted
  Solidago microphylla (A. Gray) Engelm. ex Small -- not accepted
  Solidago microphylla (Greene) Bush -- not accepted
  Solidago milleriana Mack. -- not accepted
  Solidago minor (Michx.) Fernald -- not accepted
  Solidago mirabilis Small -- not accepted
  Solidago missouriensis Nutt. -- accepted -- Missouri goldenrod, Tolmie's goldenrod, prairie goldenrod
  Solidago missouriensis var. extraria A. Gray -- not accepted
  Solidago missouriensis var. fasciculata Holz. -- not accepted -- Missouri goldenrod
  Solidago missouriensis var. glaberrima (M. Martens) Rosend. & Cronquist -- not accepted
  Solidago missouriensis var. missouriensis Nutt. -- not accepted -- Missouri goldenrod
  Solidago missouriensis var. montana A. Gray -- not accepted
  Solidago missouriensis var. tenuissima (Woot. & Standl.) C.E.S. Taylor & R.J. Taylor -- not accepted -- Missouri goldenrod
  Solidago missouriensis var. tolmieana (A. Gray) Cronquist -- not accepted -- Tolmie's goldenrod
  Solidago mollis Bartlett -- accepted -- velvety goldenrod, ashy goldenrod, soft goldenrod, woolly goldenrod
  Solidago mollis var. angustata Shinners -- not accepted -- velvety goldenrod
  Solidago mollis var. mollis Bartlett -- not accepted -- velvety goldenrod, velvet goldenrod
  Solidago monticola Torr. & A. Gray -- not accepted
  Solidago moseleyi Fernald -- not accepted
  Solidago multiradiata Aiton -- accepted -- Rocky Mountain goldenrod, manyray goldenrod, arctic goldenrod, mountain goldenrod
  Solidago multiradiata ssp. scopulorum (A. Gray) W.A. Weber -- not accepted
  Solidago multiradiata var. arctica (DC.) Fernald -- not accepted -- arctic goldenrod
  Solidago multiradiata var. multiradiata Aiton -- not accepted -- Rocky Mountain goldenrod
  Solidago multiradiata var. scopulorum A. Gray -- not accepted -- manyray goldenrod, Rocky Mountain goldenrod
  Solidago nana Nutt. -- accepted -- baby goldenrod, gray goldenrod
  Solidago neglecta Torr. & A. Gray -- not accepted
  Solidago nemoralis Aiton -- accepted -- gray goldenrod, dyersweed goldenrod
  Solidago nemoralis ssp. decemflora (DC.) Brammall -- accepted -- gray goldenrod
  Solidago nemoralis ssp. haleana (Fernald) G.W. Douglas -- not accepted
  Solidago nemoralis ssp. longipetiolata (Mack. & Bush) G.W. Douglas -- not accepted
  Solidago nemoralis ssp. nemoralis Aiton -- accepted -- gray goldenrod
  Solidago nemoralis var. decemflora (DC.) Fernald -- not accepted
  Solidago nemoralis var. haleana Fernald -- not accepted
  Solidago nemoralis var. longipetiolata (Mack. & Bush) Palmer & Steyerm. -- not accepted -- gray goldenrod
  Solidago nemoralis var. nemoralis Aiton -- not accepted -- gray goldenrod
  Solidago neomexicana (A. Gray) Woot. & Standl. -- not accepted
  Solidago neurolepis Fernald -- not accepted
  Solidago nitida Torr. & A. Gray -- accepted -- shiny goldenrod
  Solidago notabilis Mack. -- not accepted
  Solidago nuttallii (Greene) Bush -- not accepted
  Solidago occidentalis (Nutt.) Torr. & A. Gray -- not accepted
  Solidago odora Aiton -- accepted -- anise-scented goldenrod, fragrant goldenrod
  Solidago odora ssp. chapmanii (A. Gray) Semple -- accepted -- Chapman's goldenrod
  Solidago odora ssp. odora Aiton -- accepted -- anise-scented goldenrod
  Solidago odora var. chapmanii (A. Gray) Cronquist -- not accepted -- Chapman's goldenrod
  Solidago ohioensis Riddell -- accepted
  Solidago oreophila Rydb. -- not accepted
  Solidago ouachitensis C.E.S. Taylor & R.J. Taylor -- accepted -- Ouachita Mountain goldenrod
  Solidago pallida (Porter) Rydb. -- not accepted
  Solidago parryi (A. Gray) Greene -- not accepted -- Parry's goldenrod
  Solidago parvirigida Beaudry -- not accepted
  Solidago patula Muhl. ex Willd. -- accepted -- roundleaf goldenrod
  Solidago patula ssp. patula Muhl. ex Willd. -- accepted -- roundleaf goldenrod
  Solidago patula ssp. strictula Torr. & A. Gray -- accepted -- roundleaf goldenrod
  Solidago patula var. strictula Torr. & A. Gray -- not accepted -- roundleaf goldenrod
  Solidago pauciflosculosa Michx. -- not accepted
  Solidago pendula Small -- not accepted
  Solidago perglabra Friesner -- not accepted
  Solidago perlonga Fernald -- not accepted
  Solidago petiolaris Aiton -- accepted -- downy ragged goldenrod, downy goldenrod
  Solidago petiolaris var. angusta (Torr. & A. Gray) A. Gray -- not accepted -- downy ragged goldenrod
  Solidago petiolaris var. petiolaris Aiton -- not accepted -- downy ragged goldenrod
  Solidago petiolaris var. wardii (Britton) Fernald -- not accepted
  Solidago petiolata auct. non Mill. -- not accepted
  Solidago petradoria S.F. Blake -- not accepted
  Solidago pinetorum Small -- accepted -- Small's goldenrod
  Solidago pitcheri Nutt. -- not accepted
  Solidago plumosa Small -- accepted -- plumed goldenrod, Yadkin River Goldenrod
  Solidago polycephala Fernald -- not accepted
  Solidago porteri Small -- not accepted -- Porter's goldenrod
  Solidago pruinosa Greene -- not accepted
  Solidago ptarmicoides (Torr. & A. Gray) B. Boivin -- accepted -- white flat-top goldenrod, upland white aster, prairie goldenrod, verge-d'or faux-ptarmica
  Solidago pubens M.A. Curtis -- not accepted
  Solidago puberula Nutt. -- accepted -- downy goldenrod
  Solidago puberula ssp. puberula Nutt. -- accepted -- downy goldenrod
  Solidago puberula ssp. pulverulenta (Nutt.) Semple -- accepted -- downy goldenrod
  Solidago puberula var. puberula Nutt. -- not accepted -- downy goldenrod
  Solidago puberula var. pulverulenta (Nutt.) Chapm. -- not accepted -- downy goldenrod
  Solidago pulcherrima A. Nelson -- not accepted
  Solidago pulchra Small -- accepted -- Carolina goldenrod
  Solidago pulverulenta Nutt. -- not accepted
  Solidago purshii Porter -- not accepted
  Solidago racemosa Greene -- not accepted
  Solidago racemosa var. gillmanii (A. Gray) Fernald -- not accepted
  Solidago radula Nutt. -- accepted -- western rough goldenrod, rough goldenrod
  Solidago radula var. laeta (Greene) Fernald -- not accepted -- western rough goldenrod
  Solidago radula var. radula Nutt. -- not accepted -- western rough goldenrod
  Solidago radula var. stenolepis Fernald -- not accepted -- western rough goldenrod
  Solidago randii (Porter) Britton -- not accepted
  Solidago randii var. monticola (Porter) Fernald -- not accepted
  Solidago remota (Greene) Friesner -- not accepted
  Solidago riddellii Frank ex Riddell -- accepted -- Riddell's goldenrod
  Solidago rigida L. -- accepted -- stiff-leaved goldenrod
  Solidago rigida ssp. glabrata (E.L. Braun) S.B. Heard & Semple -- accepted
  Solidago rigida ssp. humilis (Porter) S.B. Heard & Semple -- accepted
  Solidago rigida ssp. rigida L. -- accepted -- stiff goldenrod
  Solidago rigida var. glabrata E.L. Braun -- not accepted
  Solidago rigida var. humilis Porter -- not accepted
  Solidago rigida var. laevicaulis Shinners -- not accepted
  Solidago rigidiuscula (Torr. & A. Gray) Porter -- not accepted
  Solidago roanensis Porter -- accepted -- Roan Mountain goldenrod
  Solidago roanensis var. monticola (Torr. & A. Gray) Fernald -- not accepted
  Solidago rotundifolia DC. -- not accepted
  Solidago rugosa Mill. -- accepted -- wrinkleleaf goldenrod
  Solidago rugosa ssp. aspera (Aiton) Cronquist -- accepted -- wrinkleleaf goldenrod, wrinkled goldenrod
  Solidago rugosa ssp. rugosa Mill. -- accepted -- wrinkleleaf goldenrod
  Solidago rugosa ssp. rugosa var. villosa (Pursh) Fernald -- not accepted -- wrinkleleaf goldenrod
  Solidago rugosa var. celtidifolia (Small) Fernald -- not accepted
  Solidago rugosa var. cronquistiana Semple -- accepted
  Solidago rugosa var. rugosa Mill. -- accepted -- wrinkleleaf goldenrod
  Solidago rugosa var. sphagnophila Graves -- accepted -- wrinkleleaf goldenrod
  Solidago rugosa var. villosa (Pursh) Fern. -- not accepted -- wrinkleleaf goldenrod
  Solidago rupestris Raf. -- accepted -- rock goldenrod
  Solidago salicina Elliot -- not accepted
  Solidago sarothrae Pursh -- not accepted
  Solidago scaberrima Torr. & A. Gray -- not accepted
  Solidago scabra Muhl. ex Willd. non Muhl. -- not accepted
  Solidago sciaphila Steele -- accepted -- shadowy goldenrod
  Solidago scopulorum (A. Gray) A. Nelson -- not accepted
  Solidago sempervirens L. -- accepted -- seaside goldenrod
  Solidago sempervirens ssp. mexicana (L.) Semple -- accepted -- seaside goldenrod
  Solidago sempervirens ssp. sempervirens L. -- accepted -- seaside goldenrod
  Solidago sempervirens var. mexicana (L.) Fernald -- not accepted -- seaside goldenrod
  Solidago sempervirens var. sempervirens L. -- not accepted -- seaside goldenrod
  Solidago serotina Aiton non Retz. -- not accepted
  Solidago serotinoides Á. Löve & D. Löve -- not accepted
  Solidago shortii Torr. & A. Gray -- accepted -- Short's goldenrod
  Solidago simplex Kunth -- accepted -- Mt. Albert goldenrod
  Solidago simplex ssp. randii (Porter) G.S. Ringius -- accepted -- Rand's goldenrod
  Solidago simplex ssp. randii var. gillmanii (A. Gray) G.S. Ringius -- not accepted -- Rand's goldenrod
  Solidago simplex ssp. randii var. monticola (Porter) G.S. Ringius -- not accepted -- Rand's goldenrod
  Solidago simplex ssp. randii var. ontarioensis (G.S. Ringius) G.S. Ringius -- not accepted -- Ontario goldenrod
  Solidago simplex ssp. randii var. randii (Porter) Kartesz & Gandhi -- not accepted -- Rand's goldenrod, mountain goldenrod, verge-d'or simple variété de Rand
  Solidago simplex ssp. simplex Kunth -- accepted -- Mt. Albert goldenrod
  Solidago simplex ssp. simplex var. chlorolepis (Fernald) G.S. Ringius -- not accepted -- Mt. Albert goldenrod, verge-d'or simple variété ŕ bractées vertes
  Solidago simplex ssp. simplex var. nana (A. Gray) G.S. Ringius -- not accepted -- dwarf goldenrod
  Solidago simplex ssp. simplex var. simplex Kunth -- not accepted -- Mt. Albert goldenrod, New Mexican goldenrod
  Solidago simplex ssp. simplex var. spathulata (DC.) Cronquist -- not accepted
  Solidago simplex var. chlorolepis (Fernald) G.S. Ringius -- accepted
  Solidago simplex var. gillmanii (A. Gray) G.S. Ringius -- accepted -- Rand's goldenrod, Deam's goldenrod
  Solidago simplex var. monticola (Porter) G.S. Ringius -- accepted -- Rand's goldenrod
  Solidago simplex var. nana (A. Gray) G.S. Ringius -- accepted -- dwarf goldenrod
  Solidago simplex var. ontarioensis (G.S. Ringius) G.S. Ringius -- accepted -- Ontario goldenrod
  Solidago simplex var. racemosa (Greene) G.S. Ringius -- accepted -- Rand's goldenrod
  Solidago simplex var. randii (Porter) Kartesz & Gandhi -- accepted -- Rand's goldenrod
  Solidago simplex var. simplex Kunth -- accepted -- Mt. Albert goldenrod
  Solidago simplex var. spathulata (DC.) Cronq. -- not accepted -- Mt. Albert goldenrod
  Solidago simulans Fernald -- not accepted -- fall goldenrod
  Solidago sparsiflora A. Gray -- not accepted
  Solidago spathulata DC. -- accepted -- coast goldenrod, Mt. Albert goldenrod
  Solidago spathulata ssp. glutinosa (Nutt.) D.D. Keck -- not accepted
  Solidago spathulata ssp. randii (Porter) Gleason -- not accepted
  Solidago spathulata ssp. spathulata DC. -- not accepted
  Solidago spathulata var. gillmanii (A. Gray) Gleason -- not accepted
  Solidago spathulata var. nana (A. Gray) Cronquist -- not accepted
  Solidago spathulata var. neomexicana (A. Gray) Cronquist -- not accepted
  Solidago spathulata var. racemosa (Greene) Gleason -- not accepted
  Solidago spathulata var. spathulata DC. -- not accepted -- coastaldune goldenrod
  Solidago spathulata var. subcinerea A. Gray -- not accepted
  Solidago speciosa Nutt. -- accepted -- showy goldenrod, noble goldenrod
  Solidago speciosa ssp. pallida (Porter) Semple -- accepted
  Solidago speciosa ssp. speciosa Nutt. -- accepted
  Solidago speciosa var. angustata Torr. & A. Gray -- not accepted
  Solidago speciosa var. erecta (Pursh) MacMill. -- not accepted -- showy goldenrod
  Solidago speciosa var. jejunifolia (E.S. Steele) Cronquist -- not accepted -- showy goldenrod
  Solidago speciosa var. pallida Porter -- accepted -- showy goldenrod
  Solidago speciosa var. rigidiuscula Torr. & A. Gray -- accepted -- showy goldenrod
  Solidago speciosa var. speciosa Nutt. -- accepted -- showy goldenrod
  Solidago spectabilis (D.C. Eaton) A. Gray -- accepted -- Nevada goldenrod
  Solidago spectabilis var. confinis (A. Gray) Cronquist -- not accepted -- Nevada goldenrod
  Solidago spectabilis var. spectabilis (D.C. Eaton) A. Gray -- accepted -- Nevada goldenrod
  Solidago sphacelata Raf. -- accepted -- autumn goldenrod
  Solidago spithamaea M.A. Curtis -- accepted -- Blue Ridge goldenrod
  Solidago squarrosa Nutt. -- accepted -- stout goldenrod
  Solidago stricta Aiton -- accepted -- wand goldenrod
  Solidago stricta ssp. gracillima (Torr. & A. Gray) Semple -- accepted -- Virginia goldenrod
  Solidago stricta ssp. stricta Aiton -- accepted
  Solidago strigosa Small -- not accepted
  Solidago suaveolens Schoepf -- not accepted
  Solidago tarda Mack. -- accepted -- Atlantic goldenrod
  Solidago tenuifolia Pursh -- not accepted
  Solidago tenuifolia var. pycnocephala Fernald -- not accepted
  Solidago tenuissima Woot. & Standl. -- not accepted
  Solidago texensis Friesner -- not accepted
  Solidago tortifolia Elliot -- accepted -- twistleaf goldenrod
  Solidago trinervata Greene -- not accepted
  Solidago uliginosa Nutt. -- accepted -- bog goldenrod, fall goldenrod
  Solidago uliginosa var. jejunifolia (E.S. Steele) B. Boivin -- not accepted
  Solidago uliginosa var. levipes (Fernald) Fernald -- not accepted -- bog goldenrod
  Solidago uliginosa var. linoides (Torr. & A. Gray) Fernald -- not accepted -- bog goldenrod
  Solidago uliginosa var. neglecta (Torr. & A. Gray) Fernald -- not accepted
  Solidago uliginosa var. peracuta (Fernald) Friesner -- not accepted
  Solidago uliginosa var. terrae-novae (Torr. & A. Gray) Fernald -- not accepted -- bog goldenrod
  Solidago uliginosa var. uliginosa Nutt. -- not accepted -- bog goldenrod
  Solidago ulmifolia Muhl. ex Willd. -- accepted -- elmleaf goldenrod
  Solidago ulmifolia var. microphylla A. Gray -- not accepted -- elmleaf goldenrod
  Solidago ulmifolia var. palmeri Cronquist -- accepted -- Palmer's goldenrod
  Solidago ulmifolia var. ulmifolia Muhl. ex Willd. -- accepted -- elmleaf goldenrod
  Solidago uniligulata (DC.) Porter -- not accepted
  Solidago uniligulata var. levipes Fernald -- not accepted
  Solidago velutina DC. -- accepted -- threenerve goldenrod, sparse goldenrod, three-nerve goldenrod
  Solidago velutina ssp. califonica (Nutt.) Semple -- accepted -- California goldenrod
  Solidago velutina ssp. sparsiflora (A. Gray) Semple -- accepted
  Solidago velutina ssp. velutina DC. -- accepted
  Solidago velutina var. nevadensis (A. Gray) C.E.S. Taylor & R.J. Taylor -- not accepted
  Solidago verna M.A. Curtis ex Torr. & A. Gray -- accepted -- springflowering goldenrod
  Solidago victorinii Fernald -- not accepted -- Victorin's goldenrod
  Solidago villosicarpa LeBlond -- accepted -- hairy-seed goldenrod
  Solidago virgauera var. arctica DC. -- not accepted
  Solidago wardii Britton -- not accepted
  Solidago wrightii A. Gray -- accepted -- Wright's goldenrod
  Solidago wrightii var. adenophora S.F. Blake -- not accepted -- Wright's goldenrod
  Solidago wrightii var. wrightii A. Gray -- not accepted -- Wright's goldenrod
  Solidago X asperula Desf. (pro sp.) -- accepted -- goldenrod
  Solidago X bartramiana Fernald (pro sp.) -- accepted
  Solidago X beaudryi B. Boivin -- accepted -- Beaudry's goldenrod
  Solidago X bernardii B. Boivin -- accepted
  Solidago X calcicola (Fernald) Fernald -- accepted -- limestone goldenrod
  Solidago X erskinei B. Boivin -- accepted -- Erskine's goldenrod
  Solidago X hirtipes Fernald -- not accepted
  Solidago X krotkovii B. Boivin -- not accepted
  Solidago X leiophallax Friesner -- not accepted
  Solidago X lutescens (Lindl. ex DC.) B. Boivin -- accepted
  Solidago X neurolepis Fernald (pro sp.) -- accepted -- Atlantic goldenrod
  Solidago X ovata Friesner (pro sp.) -- accepted -- goldenrod
  Solidago X ulmicaesia Friesner -- accepted -- goldenrod
  Solidago yadkinensis (Porter) Small -- not accepted
  Solidaster luteus (Everett) M.L. Green ex Dress -- not accepted
  Solidaster X luteus (Everett) M.L. Green ex Dress -- not accepted
  Soliva Ruiz & Pav. -- accepted -- burrweed, soliva
  Soliva anthemifolia (Juss.) R. Br. ex Less. -- accepted -- button burrweed, Mutis' burrweed
  Soliva daucifolia Nutt. -- not accepted
  Soliva mutisii Kunth -- not accepted -- Mutis' burrweed
  Soliva nasturtiifolia auct. non (Juss.) DC. -- not accepted
  Soliva pterosperma (Juss.) Less. -- not accepted -- field burrweed
  Soliva sessilis Ruiz & Pav. -- accepted -- field burrweed, field soliva
  Soliva stolonifera (Brot.) Sweet -- accepted -- carpet burrweed
  Sonchus L. -- accepted -- sowthistle, sow thistle
  Sonchus arvensis L. -- accepted -- field sowthistle, field sow-thistle, sowthistle, creeping sowthistle, perennial sowthistle
  Sonchus arvensis ssp. arvensis L. -- accepted -- field sowthistle, field sow-thistle, creeping sowthistle, perennial sowthistle
  Sonchus arvensis ssp. uliginosus (M. Bieb.) Nyman -- accepted -- moist sowthistle, field sow-thistle, marsh sowthistle, field sowthistle, perennial sowthistle, sowthistle
  Sonchus arvensis var. glabrescens Guenth., Grab. & Wimm. -- not accepted
  Sonchus arvensis var. shumovichii B. Boivin -- not accepted
  Sonchus asper (L.) Hill -- accepted -- spiny sowthistle, prickly sow thistle, prickly sowthistle, spiny-leaf sow-thistle, perennial sowthistle
  Sonchus asper ssp. asper (L.) Hill -- not accepted -- spiny sowthistle
  Sonchus asper ssp. glaucescens (Jord.) J. Ball -- not accepted -- spiny sowthistle
  Sonchus nymanii Tineo & Guss. -- not accepted
  Sonchus oleraceus L. -- accepted -- common sowthistle, sow-thistle, common sow-thistle, annual sowthistle, pualele, sow thistle
  Sonchus palustris L. -- accepted -- marsh sowthistle
  Sonchus tataricus L. -- not accepted
  Sonchus tenerrimus L. -- accepted -- slender sowthistle
  Sonchus uliginosus M. Bieb. -- not accepted
  Sparganophorus Vaill. ex Crantz -- accepted
  Sparganophorus sparganophora (L.) C. Jeffrey -- accepted -- yerba de faja
  Sphaeromeria Nutt. -- accepted -- chickensage, sphaeromeria
  Sphaeromeria argentea Nutt. -- accepted -- silver chickensage
  Sphaeromeria cana (D.C. Eaton) A. Heller -- accepted -- gray chickensage, gray tansey
  Sphaeromeria capitata Nutt. -- accepted -- rock tansy
  Sphaeromeria compacta (H.M. Hall) A.H. Holmgren, L.M. Shultz & Lowrey -- accepted -- compact chickensage, Charleston tansy
  Sphaeromeria diversifolia (D.C. Eaton) Rydb. -- accepted -- separateleaf chickensage
  Sphaeromeria potentilloides (A. Gray) A. Heller -- accepted -- fivefinger chickensage, cinquefoil chickensage
  Sphaeromeria potentilloides var. nitrophila (Cronquist) A.H. Holmgren, L.M. Shultz & Lowrey -- accepted -- fivefinger chickensage, alkali chickensage
  Sphaeromeria potentilloides var. potentilloides (A. Gray) A. Heller -- accepted -- fivefinger chickensage, false chicken-sage
  Sphaeromeria ruthiae A.H. Holmgren, L.M. Shultz & Lowrey -- accepted -- Zion chickensage
  Sphaeromeria simplex (A. Nelson) A. Heller -- accepted -- Laramie chickensage
  Sphagneticola O. Hoffm. -- accepted -- creeping-oxeye
  Sphagneticola gracilis (Rich.) Pruski -- accepted -- slender creeping-oxeye
  Sphagneticola trilobata (L.) Pruski -- accepted -- Bay Biscayne creeping-oxeye
  Spilanthes Jacq. -- accepted -- spilanthes
  Spilanthes acmella (L.) L. -- accepted -- para cress
  Spilanthes americana auct. non Hieron. -- not accepted
  Spilanthes americana var. repens (Walter) A.H. Moore -- not accepted
  Spilanthes americana var. stolonifera (DC.) A.H. Moore -- not accepted
  Spilanthes iodiscaea A.H. Moore -- not accepted
  Spilanthes oleracea L. -- accepted -- spilanthes
  Spilanthes pusilla Hook. & Arn. -- not accepted
  Spilanthes stolonifera DC. -- not accepted
  Spilanthes uliginosa Sw. -- not accepted
  Spilanthes urens Jacq. -- accepted -- pigeoncoop
  Spiracantha Kunth -- accepted -- dogwoodleaf
  Spiracantha cornifolia Kunth -- accepted -- dogwoodleaf
  Starkea pinnata Nutt. -- not accepted
  Stebbinsoseris K.L. Chambers -- accepted -- silverpuffs
  Stebbinsoseris decipiens (K.L. Chambers) Chambers -- accepted -- Santa Cruz silverpuffs
  Stebbinsoseris heterocarpa (Nutt.) K.L. Chambers -- accepted -- grassland silverpuffs, silverpuffs
  Stenactis annua (L.) Nees -- not accepted
  Stenactis strigosa (Muhl. ex Willd.) DC. -- not accepted
  Stenotopsis interior (Coville) Rydb. -- not accepted
  Stenotopsis linearifolia (DC.) Rydb. -- not accepted
  Stenotopsis linearifolia var. interior (Coville) H.M. Hall -- not accepted
  Stenotus Nutt. -- accepted -- mock goldenweed, stenotus
  Stenotus acaulis (Nutt.) Nutt. -- accepted -- stemless mock goldenweed, stemless goldenweed
  Stenotus acaulis var. acaulis (Nutt.) Nutt. -- not accepted -- stemless goldenweed, stemless mock goldenweed
  Stenotus acaulis var. glabratus (D.C. Eaton) Kartesz & Gandhi -- not accepted -- stemless mock goldenweed
  Stenotus andersonii Rydb. -- not accepted
  Stenotus armerioides Nutt. -- accepted -- thrift mock goldenweed
  Stenotus armerioides var. armerioides Nutt. -- accepted -- thrift mock goldenweed, goldenweed, thrifty goldenweed
  Stenotus armerioides var. gramineus (S.L. Welsh & F.J. Sm.) Kartesz & Gandhi -- accepted -- grass-like mock goldenweed, grasslike mock goldenweed
  Stenotus lanuginosus (A. Gray) Greene -- accepted -- woolly mock goldenweed
  Stenotus lanuginosus var. andersonii (Rydb.) H.M. Hall -- accepted -- Anderson's mock goldenweed, Anderson's goldenweed
  Stenotus lanuginosus var. lanuginosus (A. Gray) Greene -- accepted -- woolly mock goldenweed
  Stenotus macleanii (Brandegee) A. Heller -- not accepted
  Stenotus stenophyllus (A. Gray) Greene -- not accepted -- narrowleaf mock goldenweed, linearleaf goldenbush
  Stephanomeria Nutt. -- accepted -- wirelettuce, wire lettuce
  Stephanomeria blairii Munz & I.M. Johnst. -- not accepted -- Blair's wirelettuce
  Stephanomeria carotifera Hoover -- not accepted
  Stephanomeria cichoriacea A. Gray -- accepted -- chicoryleaf wirelettuce
  Stephanomeria cinerea (S.F. Blake) S.F. Blake -- not accepted
  Stephanomeria coronaria Greene -- not accepted
  Stephanomeria diegensis Gottlieb -- accepted -- wreathplant
  Stephanomeria elata Nutt. -- accepted -- Santa Barbara wirelettuce
  Stephanomeria exigua Nutt. -- accepted -- small wirelettuce, wire lettuce
  Stephanomeria exigua ssp. carotifera (Hoover) Gottlieb -- accepted -- whiteplume wirelettuce
  Stephanomeria exigua ssp. coronaria (Greene) Gottlieb -- accepted -- whiteplume wirelettuce
  Stephanomeria exigua ssp. deanei (J.F. Macbr.) Gottlieb -- accepted -- Deane's wirelettuce
  Stephanomeria exigua ssp. exigua Nutt. -- accepted -- small wirelettuce, Schott's wirelettuce, wire lettuce
  Stephanomeria exigua ssp. macrocarpa Gottlieb -- accepted -- whiteplume wirelettuce
  Stephanomeria exigua ssp. pentachaeta D.C. Eaton -- not accepted
  Stephanomeria exigua var. coronaria (Greene) Jeps. -- not accepted
  Stephanomeria exigua var. deanei J.F. Macbr. -- not accepted
  Stephanomeria exigua var. pentachaeta (D.C. Eaton) H.M. Hall -- not accepted
  Stephanomeria fluminea Gottlieb -- accepted -- Teton wirelettuce
  Stephanomeria lactucina A. Gray -- accepted -- lettuce wirelettuce, creeping wirelettuce
  Stephanomeria lygodesmoides M.E. Jones -- not accepted -- skeletonweed, skeleton wirelettuce
  Stephanomeria malheurensis Gottlieb -- accepted -- Malheur wirelettuce, Malheur wire lettuce, Malheur wire-lettuce
  Stephanomeria minor (Hook.) Nutt. -- not accepted -- lesser wirelettuce
  Stephanomeria minor var. minor (Hook.) Nutt. -- not accepted -- narrowleaf wirelettuce
  Stephanomeria minor var. myrioclada (D.C. Eaton) Kartesz -- not accepted -- narrowleaf wirelettuce
  Stephanomeria minor var. uintaensis (Goodrich & S.L. Welsh) Kartesz -- not accepted -- Uinta wirelettuce
  Stephanomeria myrioclada D.C. Eaton -- not accepted
  Stephanomeria neomexicana (Greene) Cory -- not accepted
  Stephanomeria paniculata Nutt. -- accepted -- tufted wirelettuce
  Stephanomeria parryi A. Gray -- accepted -- Parry's wirelettuce, Parry's wire lettuce
  Stephanomeria pauciflora (Torr.) A. Nelson -- accepted -- brownplume wirelettuce, skeletonweed, wire-lettuce, wire lettuce, fewflower wirelettuce
  Stephanomeria pauciflora var. parishii (Jeps.) Munz -- not accepted
  Stephanomeria pauciflora var. pauciflora (Torr.) A. Nelson -- not accepted
  Stephanomeria runcinata Nutt. -- accepted -- desert wirelettuce, flowering-straw
  Stephanomeria schottii A. Gray -- not accepted -- Schott's wirelettuce, Schott's wire lettuce
  Stephanomeria spinosa (Nutt.) S. Tomb -- not accepted -- thorn skeletonweed, thorny wire-lettuce, spiny skeletonweed
  Stephanomeria tenuifolia (Raf.) H.M. Hall -- accepted -- narrowleaf wirelettuce, Uinta wirelettuce, lesser wirelettuce, Wright's wirelettuce
  Stephanomeria tenuifolia var. myrioclada (D.C. Eaton) Cronquist -- not accepted -- narrowleaf wirelettuce
  Stephanomeria tenuifolia var. tenuifolia (Raf.) H.M. Hall -- not accepted -- narrowleaf wirelettuce
  Stephanomeria tenuifolia var. uintaensis Goodrich & S.L. Welsh -- not accepted -- Uinta wirelettuce
  Stephanomeria thurberi A. Gray -- accepted -- Thurber's wirelettuce, Thurber's wire lettuce
  Stephanomeria virgata Benth. -- accepted -- rod wirelettuce, tall wirelettuce
  Stephanomeria virgata ssp. pleurocarpa (Greene) Gottlieb -- accepted -- wand wirelettuce
  Stephanomeria virgata ssp. virgata Benth. -- accepted -- rod wirelettuce
  Stephanomeria virgata var. tomentosa (Greene) Munz -- not accepted
  Stephanomeria wrightii A. Gray -- not accepted -- Wright's wirelettuce
  Stevia Cav. -- accepted -- candyleaf
  Stevia lemmonii (A. Gray) A. Gray -- accepted -- Lemmon's candyleaf, Lemmon's stevia
  Stevia micrantha Lag. -- accepted -- annual candyleaf
  Stevia ovata Willd. -- accepted -- roundleaf candyleaf
  Stevia ovata var. ovata Willd. -- accepted -- roundleaf candyleaf
  Stevia ovata var. texana Grashoff -- accepted -- Texan candyleaf
  Stevia plummerae A. Gray -- accepted -- Plummer's candyleaf
  Stevia plummerae var. alba A. Gray -- not accepted -- Plummer's candyleaf
  Stevia plummerae var. plummerae A. Gray -- accepted -- Plummer's candyleaf
  Stevia rebaudiana (Bertoni) Bertoni -- accepted -- candyleaf
  Stevia rhombifolia Kunth -- not accepted
  Stevia salicifolia Cav. -- accepted -- willowleaf candyleaf
  Stevia salicifolia var. stenophylla (A. Gray) B.L. Rob. -- not accepted
  Stevia serrata Cav. -- accepted -- sawtooth candyleaf, saw-tooth candyleaf
  Stevia serrata var. haplopappa B.L. Rob. -- not accepted
  Stevia serrata var. ivifolia (Willd.) B.L. Rob. -- not accepted
  Stevia stenophylla A. Gray -- not accepted
  Stevia viscida Kunth -- accepted -- viscid candyleaf
  Stokesia L'Hér. -- accepted -- stokesia
  Stokesia laevis (Hill) Greene -- accepted -- Stokes' aster
  Struchium P. Br. -- accepted -- struchium
  Struchium sparganophorum (L.) Kuntze -- not accepted -- yerba de faja
  Stylocline Nutt. -- accepted -- neststraw, stylocline
  Stylocline acaulis Kellogg -- not accepted
  Stylocline amphibola (A. Gray) J.T. Howell -- not accepted
  Stylocline citroleum Morefield -- accepted -- oil neststraw
  Stylocline filaginea (A. Gray) A. Gray -- not accepted
  Stylocline filaginea var. depressa Jeps. -- not accepted
  Stylocline gnaphalioides Nutt. -- not accepted -- mountain neststraw
  Stylocline gnaphaloides Nutt. -- accepted -- mountain neststraw
  Stylocline intertexta Morefield -- accepted -- Morefield's neststraw
  Stylocline masonii Morefield -- accepted -- Mason's neststraw
  Stylocline micropoides A. Gray -- accepted -- woollyhead neststraw, desert neststraw, woolly neststraw
  Stylocline psilocarphoides M. Peck -- accepted -- baretwig neststraw
  Stylocline sonorensis Wiggins -- accepted -- Sonoran neststraw
  Stylopappus elatus Nutt. -- not accepted
  Symphyotrichum Nees -- accepted -- aster
  Symphyotrichum adnatum (Nutt.) G.L. Nesom -- accepted -- scaleleaf aster
  Symphyotrichum anomalum (Engelm. ex Torr. & A. Gray) G.L. Nesom -- accepted -- manyray aster
  Symphyotrichum anticostense (Fernald) G.L. Nesom -- accepted -- Anticosti Island aster
  Symphyotrichum ascendens (Lindl.) G.L. Nesom -- accepted -- western aster
  Symphyotrichum bahamense (Britton) G.L. Nesom -- not accepted -- Bahaman aster
  Symphyotrichum boreale (Torr. & A. Gray) A. Löve & D. Löve -- accepted -- northern bog aster
  Symphyotrichum bracei (Britton ex Small) G.L. Nesom -- not accepted -- Brace's aster
  Symphyotrichum bracteolatum auct. non (Nutt.) G.L. Nesom -- not accepted
  Symphyotrichum campestre (Nutt.) G.L. Nesom -- accepted -- western meadow aster
  Symphyotrichum campestre var. bloomeri (Nutt.) G.L. Nesom -- not accepted -- Bloomer's aster
  Symphyotrichum campestre var. campestre (Nutt.) G.L. Nesom -- not accepted -- western meadow aster
  Symphyotrichum chapmanii (Torr. & A. Gray) Semple & Brouillet -- accepted -- savannah aster
  Symphyotrichum chilense (Nees) G.L. Nesom -- accepted -- Pacific aster
  Symphyotrichum chilense var. chilense (Nees) G.L. Nesom -- not accepted -- Pacific aster
  Symphyotrichum chilense var. invenustum (Greene) G.L. Nesom -- not accepted -- Pacific aster
  Symphyotrichum chilense var. medium (Jeps.) G.L. Nesom -- not accepted -- Pacific aster
  Symphyotrichum ciliatum (Ledeb.) G.L. Nesom -- accepted -- rayless alkali aster
  Symphyotrichum ciliolatum (Lindl.) A. Löve & D. Löve -- accepted -- Lindley's aster
  Symphyotrichum ciliolatum var. comatum (Fernald) G.L. Nesom -- not accepted
  Symphyotrichum ciliolatum var. maccallae (Rydb.) G.L. Nesom -- not accepted
  Symphyotrichum ciliolatum var. wilsonii (Rydb.) G.L. Nesom -- not accepted
  Symphyotrichum concolor (L.) G.L. Nesom -- accepted -- eastern silver aster
  Symphyotrichum concolor var. concolor (L.) G.L. Nesom -- accepted -- eastern silvery aster
  Symphyotrichum concolor var. devestitum (S.F. Blake) Semple -- accepted
  Symphyotrichum cordifolium (L.) G.L. Nesom -- accepted -- common blue wood aster
  Symphyotrichum cordifolium var. furbishiae (Fernald) G.L. Nesom -- not accepted
  Symphyotrichum cordifolium var. lanceolatum (Porter) G.L. Nesom -- not accepted
  Symphyotrichum cordifolium var. moratum (Shinners) G.L. Nesom -- not accepted
  Symphyotrichum cordifolium var. polycephalum (Porter) G.L. Nesom -- not accepted
  Symphyotrichum cordifolium var. racemiflorum (Fernald) G.L. Nesom -- not accepted
  Symphyotrichum crenifolium (Fernald) G.L. Nesom -- not accepted
  Symphyotrichum cusickii (A. Gray) G.L. Nesom -- accepted -- Cusick's aster
  Symphyotrichum defoliatum (Parish) G.L. Nesom -- accepted -- San Bernardino aster
  Symphyotrichum depauperatum (Fernald) G.L. Nesom -- accepted -- serpentine aster
  Symphyotrichum divaricatum (Nutt.) G.L. Nesom -- not accepted -- southern annual saltmarsh aster
  Symphyotrichum drummondii (Lindl.) G.L. Nesom -- accepted -- Drummond's aster
  Symphyotrichum drummondii var. drummondii (Lindl.) G.L. Nesom -- accepted -- Drummond's aster
  Symphyotrichum drummondii var. parviceps (Shinners) G.L. Nesom -- not accepted
  Symphyotrichum drummondii var. texanum (E.S. Burgess) G.L. Nesom -- accepted -- Drummond's aster
  Symphyotrichum dumosum (L.) G.L. Nesom -- accepted -- rice button aster
  Symphyotrichum dumosum var. dodgei (Fernald) G.L. Nesom -- not accepted
  Symphyotrichum dumosum var. dumosum (L.) G.L. Nesom -- accepted -- rice button aster
  Symphyotrichum dumosum var. gracilipes (Wiegand) G.L. Nesom -- accepted -- rice button aster
  Symphyotrichum dumosum var. pergracile (Wiegand) G.L. Nesom -- accepted -- rice button aster
  Symphyotrichum dumosum var. strictior (Torr. & A. Gray) G.L. Nesom -- accepted -- rice button aster
  Symphyotrichum dumosum var. subulifolium (Torr. & A. Gray) G.L. Nesom -- accepted -- rice button aster
  Symphyotrichum eatonii (A. Gray) G.L. Nesom -- accepted -- Eaton's aster
  Symphyotrichum elliotii (Torr. & A. Gray) G.L. Nesom -- accepted -- Elliott's aster
  Symphyotrichum ericoides (L.) G.L. Nesom -- accepted -- white heath aster
  Symphyotrichum ericoides var. ericoides (L.) G.L. Nesom -- accepted -- white heath aster
  Symphyotrichum ericoides var. pansum (S.F. Blake) G.L. Nesom -- accepted -- manyflowered aster
  Symphyotrichum ericoides var. prostratum (Kuntze) G.L. Nesom -- not accepted -- white heath aster
  Symphyotrichum ericoides var. stricticaule (Torr. & A. Gray) G.L. Nesom -- not accepted -- white heath aster
  Symphyotrichum eulae (Shinners) G.L. Nesom -- accepted -- Texas aster
  Symphyotrichum expansum (Poepp. ex Spreng.) G.L. Nesom -- not accepted -- southwestern annual saltmarsh aster
  Symphyotrichum falcatum (Lindl.) G.L. Nesom -- accepted -- white prairie aster
  Symphyotrichum falcatum var. commutatum (Torr. & A. Gray) G.L. Nesom -- accepted -- white prairie aster
  Symphyotrichum falcatum var. crassulum (Rydb.) G.L. Nesom -- not accepted -- white prairie aster
  Symphyotrichum falcatum var. falcatum (Lindl.) G.L. Nesom -- accepted -- white prairie aster
  Symphyotrichum fendleri (A. Gray) G.L. Nesom -- accepted -- Fendler's aster
  Symphyotrichum firmum (Nees) G.L. Nesom -- accepted -- glossy-leaved aster
  Symphyotrichum foliaceum (Lindl. ex DC.) G.L. Nesom -- accepted -- alpine leafybract aster
  Symphyotrichum foliaceum var. apricum (A. Gray) G.L. Nesom -- accepted -- alpine leafybract aster
  Symphyotrichum foliaceum var. canbyi (A. Gray) G.L. Nesom -- accepted -- Canby's aster
  Symphyotrichum foliaceum var. foliaceum (Lindl. ex DC.) G.L. Nesom -- accepted -- alpine leafybract aster
  Symphyotrichum foliaceum var. parryi (D.C. Eaton) G.L. Nesom -- accepted -- Parry's aster
  Symphyotrichum fontinale (Alexander) G.L. Nesom -- accepted -- Florida water aster
  Symphyotrichum frondosum (Nutt.) G.L. Nesom -- accepted -- short-rayed alkali aster
  Symphyotrichum georgianum (Alexander) G.L. Nesom -- accepted -- Georgia aster
  Symphyotrichum grandiflorum (L.) G.L. Nesom -- accepted -- largeflower aster
  Symphyotrichum greatae (Parish) G.L. Nesom -- accepted -- Greata's aster
  Symphyotrichum hallii (A. Gray) G.L. Nesom -- accepted -- Hall's aster
  Symphyotrichum hendersonii (Fernald) G.L. Nesom -- accepted -- Lyall aster
  Symphyotrichum hesperium (A. Gray) Á. Löve & D. Löve -- not accepted
  Symphyotrichum jessicae (Piper) G.L. Nesom -- accepted -- Jessica's aster
  Symphyotrichum kralii G.L. Nesom -- accepted -- Kral's aster
  Symphyotrichum laeve (L.) Á. Löve & D. Löve -- accepted -- smooth blue aster
  Symphyotrichum laeve var. concinnum (Willd.) G.L. Nesom -- accepted -- smooth blue aster
  Symphyotrichum laeve var. geyeri (A. Gray) G.L. Nesom -- accepted -- Geyer's aster
  Symphyotrichum laeve var. laeve (L.) Á. Löve & D. Löve -- accepted -- smooth blue aster
  Symphyotrichum laeve var. purpuratum (Nees) G.L. Nesom -- accepted -- smooth blue aster
  Symphyotrichum lanceolatum (Willd.) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lanceolatum ssp. hesperium (A. Gray) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lanceolatum ssp. hesperium var. hesperium (A. Gray) G.L. Nesom -- not accepted
  Symphyotrichum lanceolatum ssp. lanceolatum (Willd.) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lanceolatum ssp. lanceolatum var. hirsuticaule (Semple & Chmiel.) G.L. Nesom -- not accepted
  Symphyotrichum lanceolatum ssp. lanceolatum var. interior (Wiegand) G.L. Nesom -- not accepted
  Symphyotrichum lanceolatum ssp. lanceolatum var. lanceolatum (Willd.) G.L. Nesom -- not accepted
  Symphyotrichum lanceolatum ssp. lanceolatum var. latifolium (Semple & Chmiel.) G.L. Nesom -- not accepted
  Symphyotrichum lanceolatum var. hesperium (A. Gray) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lanceolatum var. hirsuticaule (Semple & Chmiel.) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lanceolatum var. interior (Wiegand) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lanceolatum var. lanceolatum (Willd.) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lanceolatum var. latifolium (Semple & Chmiel.) G.L. Nesom -- accepted -- white panicle aster
  Symphyotrichum lateriflorum (L.) Á. Löve & D. Löve -- accepted -- calico aster
  Symphyotrichum lateriflorum var. angustifolium (Wiegand) G.L. Nesom -- accepted -- calico aster
  Symphyotrichum lateriflorum var. flagellare (Shinners) G.L. Nesom -- accepted -- calico aster
  Symphyotrichum lateriflorum var. hirsuticaule (Lindl. ex DC.) G.L. Nesom -- not accepted -- calico aster
  Symphyotrichum lateriflorum var. horizontale (Desf.) G.L. Nesom -- accepted -- calico aster
  Symphyotrichum lateriflorum var. lateriflorum (L.) Á. Löve & D. Löve -- accepted -- calico aster
  Symphyotrichum lateriflorum var. spatelliforme (Burgess) G.L. Nesom -- accepted -- calico aster
  Symphyotrichum lateriflorum var. tenuipes (Wiegand) G.L. Nesom -- accepted -- calico aster
  Symphyotrichum laurentianum (Fernald) G.L. Nesom -- accepted -- Gulf of St. Lawrence aster
  Symphyotrichum lentum (Greene) G.L. Nesom -- accepted -- Suisun Marsh aster
  Symphyotrichum longifolium sensu G.L. Nesom non Lam. -- not accepted
  Symphyotrichum longifolium (Lam.) G.L. Nesom, as to type -- not accepted
  Symphyotrichum lowrieanum (Porter) G.L. Nesom -- not accepted -- Lowrie's blue wood aster
  Symphyotrichum molle (Rydb.) G.L. Nesom -- accepted -- soft aster
  Symphyotrichum nahanniense (Cody) Semple -- accepted -- Nahanni aster
  Symphyotrichum novae-angliae (L.) G.L. Nesom -- accepted -- New England aster
  Symphyotrichum novi-belgii (L.) G.L. Nesom -- accepted -- New York aster
  Symphyotrichum novi-belgii var. crenifolium (Fernald) J. Labrecque & L. Brouillet -- accepted -- Newfoundland aster
  Symphyotrichum novi-belgii var. elodes (Torr. & A. Gray) G.L. Nesom -- accepted -- New York aster
  Symphyotrichum novi-belgii var. litoreum (A. Gray) G.L. Nesom -- not accepted
  Symphyotrichum novi-belgii var. novi-belgii (L.) G.L. Nesom -- accepted -- New York aster
  Symphyotrichum novi-belgii var. tardiflorum (L.) G.L. Nesom -- not accepted
  Symphyotrichum novi-belgii var. villicaule (A. Gray) J. Labrecque & L. Brouillet -- accepted -- hairy New York aster
  Symphyotrichum oblongifolium (Nutt.) G.L. Nesom -- accepted -- aromatic aster
  Symphyotrichum ontarione (Wiegand) G.L. Nesom -- not accepted -- bottomland aster
  Symphyotrichum ontarione var. glabratum (Semple) L. Brouillet & Bouchard -- not accepted
  Symphyotrichum ontarionis (Wiegand) G.L. Nesom -- accepted -- bottomland aster, Ontario aster
  Symphyotrichum ontarionis var. glabratum (Semple) L. Brouillet & Bouchard -- accepted -- bottomland aster, Ontario aster
  Symphyotrichum ontarionis var. ontarionis (Wiegand) G.L. Nesom -- accepted
  Symphyotrichum oolentangiense (Riddell) G.L. Nesom -- accepted -- skyblue aster
  Symphyotrichum oolentangiense var. oolentangiense (Riddell) G.L. Nesom -- not accepted -- skyblue aster
  Symphyotrichum oolentangiense var. poaceum (Burgess) G.L. Nesom -- not accepted -- skyblue aster
  Symphyotrichum parviceps (E.S. Burgess) G.L. Nesom -- accepted -- smallhead aster
  Symphyotrichum patens (Aiton) G.L. Nesom -- accepted -- late purple aster
  Symphyotrichum patens var. gracile (Hook.) G.L. Nesom -- accepted -- late purple aster
  Symphyotrichum patens var. patens (Aiton) G.L. Nesom -- accepted -- late purple aster
  Symphyotrichum patens var. patentissimum (Lindl. ex DC.) G.L. Nesom -- accepted -- late purple aster
  Symphyotrichum phlogifolium (Muhl. ex Willd.) G.L. Nesom -- accepted -- thinleaf late purple aster
  Symphyotrichum pilosum (Willd.) G.L. Nesom -- accepted -- hairy white oldfield aster
  Symphyotrichum pilosum var. pilosum (Willd.) G.L. Nesom -- accepted -- hairy white oldfield aster
  Symphyotrichum pilosum var. pringlei (A. Gray) G.L. Nesom -- accepted -- Pringle's aster
  Symphyotrichum plumosum (Small) Semple -- accepted
  Symphyotrichum porteri (A. Gray) G.L. Nesom -- accepted -- smooth white aster
  Symphyotrichum potosinum (A. Gray) G.L. Nesom -- accepted -- Santa Rita Mountain aster
  Symphyotrichum praealtum (Poir.) G.L. Nesom -- accepted -- willowleaf aster
  Symphyotrichum praealtum var. angustior (Wiegand) G.L. Nesom -- not accepted -- willowleaf aster
  Symphyotrichum praealtum var. nebraskense (Britton) G.L. Nesom -- not accepted -- Nebraska aster
  Symphyotrichum praealtum var. praealtum (Poir.) G.L. Nesom -- not accepted -- willowleaf aster
  Symphyotrichum praealtum var. subasperum (Lindl.) G.L. Nesom -- not accepted -- willowleaf aster
  Symphyotrichum praealtum var. texicola (Wiegand) G.L. Nesom -- not accepted
  Symphyotrichum pratense (Raf.) G.L. Nesom -- accepted -- barrens silky aster
  Symphyotrichum prenanthoides (Muhl. ex Willd.) G.L. Nesom -- accepted -- crookedstem aster
  Symphyotrichum priceae (Britton) G.L. Nesom -- accepted -- lavender oldfield aster
  Symphyotrichum puniceum (L.) Á. Löve & D. Löve -- accepted -- purplestem aster
  Symphyotrichum puniceum var. calderi (Boivin) G.L. Nesom -- not accepted
  Symphyotrichum puniceum var. puniceum (L.) Á. Löve & D. Löve -- accepted -- purplestem aster
  Symphyotrichum puniceum var. scabricaule (Shinners) G.L. Nesom -- accepted -- purplestem aster
  Symphyotrichum pygmaeum (Lindl.) Brouillet & S. Selliah -- accepted -- pygmy aster
  Symphyotrichum racemosum (Elliot) G.L. Nesom -- accepted -- smooth white oldfield aster
  Symphyotrichum racemosum var. subdumosum (Wiegand) G.L. Nesom -- not accepted
  Symphyotrichum retroflexum (Lindl. ex DC.) G.L. Nesom -- accepted -- rigid whitetop aster
  Symphyotrichum rhiannon Weakley & Govus -- accepted -- Rhiannon's aster
  Symphyotrichum robynsianum (Rouss.) L. Brouillet & Labrecque -- accepted -- longleaf aster
  Symphyotrichum sagittifolium (Wedem. ex Willd.) G.L. Nesom -- not accepted
  Symphyotrichum sericeum (Vent.) G.L. Nesom -- accepted -- western silver aster
  Symphyotrichum shortii (Lindl.) G.L. Nesom -- accepted -- Short's aster
  Symphyotrichum simmondsii (Small) G.L. Nesom -- accepted -- Simmonds' aster
  Symphyotrichum simplex (Willd.) A. Löve & D. Löve -- not accepted
  Symphyotrichum spathulatum (Lindl.) G.L. Nesom -- accepted -- western mountain aster
  Symphyotrichum spathulatum var. fremontii (Torr. & A. Gray) G.L. Nesom -- not accepted
  Symphyotrichum spathulatum var. intermedium (A. Gray) G.L. Nesom -- accepted -- larger western mountain aster
  Symphyotrichum spathulatum var. spathulatum (Lindl.) G.L. Nesom -- accepted -- western mountain aster
  Symphyotrichum spathulatum var. yosemitanum (A. Gray) G.L. Nesom -- accepted -- western bog aster
  Symphyotrichum squamatum (Spreng.) G.L. Nesom -- not accepted -- southeastern annual saltmarsh aster
  Symphyotrichum subgeminatum (Fernald) G.L. Nesom -- not accepted
  Symphyotrichum subspicatum (Nees) G.L. Nesom -- accepted -- Douglas aster
  Symphyotrichum subspicatum var. grayi (Suksd.) G.L. Nesom -- not accepted -- Gray's aster
  Symphyotrichum subspicatum var. subspicatum (Nees) G.L. Nesom -- not accepted -- Douglas aster
  Symphyotrichum subulatum (Michx.) G.L. Nesom -- accepted -- eastern annual saltmarsh aster
  Symphyotrichum subulatum var. elongatum (Bosserdet ex A.G. Jones & Lowry) S.D. Sundb. -- accepted -- Bahaman aster
  Symphyotrichum subulatum var. ligulatum (Shinners) S.D. Sundb. -- accepted -- southern annual saltmarsh aster
  Symphyotrichum subulatum var. parviflorum (Nees) S.D. Sundb. -- accepted -- southwestern annual saltmarsh aster
  Symphyotrichum subulatum var. squamatum (Sprengel) S.D. Sundb. -- accepted -- southeastern annual saltmarsh aster
  Symphyotrichum subulatum var. subulatum (Michx.) G.L. Nesom -- accepted -- eastern annual saltmarsh aster
  Symphyotrichum tardiflorum (L.) Greuter, M.V. Agab. & Wagenitz (pro hybrid) -- not accepted
  Symphyotrichum tenuifolium (L.) G.L. Nesom -- accepted -- perennial saltmarsh aster
  Symphyotrichum tenuifolium var. aphyllum (R.W. Long) S.D. Sundb. -- accepted -- Brace's aster
  Symphyotrichum tenuifolium var. tenuifolium (L.) G.L. Nesom -- accepted
  Symphyotrichum tradescantii (L.) G.L. Nesom -- accepted -- shore aster
  Symphyotrichum turbinellum (Lindl.) G.L. Nesom -- accepted -- smooth violet prairie aster
  Symphyotrichum undulatum (L.) G.L. Nesom -- accepted -- wavyleaf aster, waxyleaf aster
  Symphyotrichum urophyllum (Lindl.) G.L. Nesom -- accepted -- white arrowleaf aster
  Symphyotrichum vahlii (Gaudich.) G.L. Nesom -- accepted
  Symphyotrichum vahlii var. vahlii (Gaudich.) G.L. Nesom -- accepted
  Symphyotrichum walteri (Alexander) G.L. Nesom -- accepted -- Walter's aster
  Symphyotrichum welshii (Cronquist) G.L. Nesom -- accepted -- Welsh's aster
  Symphyotrichum X amethystinum (Nutt.) G.L. Nesom -- accepted
  Symphyotrichum X batesii (Rydb.) G.L. Nesom -- accepted
  Symphyotrichum X columbianum (Piper) G.L. Nesom -- accepted
  Symphyotrichum X finkii (Rydb.) G.L. Nesom (pro sp.) -- accepted
  Symphyotrichum X gravesii (Burgess) G.L. Nesom -- accepted
  Symphyotrichum X longulum (Sheldon) G.L. Nesom -- accepted
  Symphyotrichum X salignum (Willd.) G.L. Nesom -- accepted
  Symphyotrichum X schistosum (Steele) G.L. Nesom -- accepted
  Symphyotrichum X subgeminatum (Fernald) G.L. Nesom (pro sp.) -- accepted
  Symphyotrichum X tardiflorum (L.) Greuter, M.V. Agab. & Wagenitz -- accepted
  Symphyotrichum X versicolor (Willd.) G.L. Nesom -- accepted
  Symphyotrichum X woldenii (Rydb.) G.L. Nesom -- accepted
  Symphyotrichum yukonense (Cronquist) G.L. Nesom -- accepted -- Yukon aster
  Synedrella Gaertn. -- accepted -- synedrella
  Synedrella nodiflora (L.) Gaertn. -- accepted -- nodeweed
  Synedrella vialis (Less.) A. Gray -- not accepted
  Synedrellopsis grisebachii auct. non Hieron. & Kuntze -- not accepted
  Synosma Raf. ex Britt. -- not accepted -- synosma
  Synosma suaveolens (L.) Raf. ex Britton -- not accepted
  Syntrichopappus A. Gray -- accepted -- Fremont's-gold, Fremont's gold
  Syntrichopappus fremontii A. Gray -- accepted -- yellowray Fremont's-gold, yellow-ray Fremont's-gold, Fremont's gold
  Syntrichopappus lemmonii (A. Gray) A. Gray -- accepted -- pinkray Fremont's-gold
  Tagetes L. -- accepted -- marigold
  Tagetes alamensis Rydb. -- not accepted
  Tagetes bonariensis Pers. -- not accepted
  Tagetes corymbosa Sweet -- not accepted
  Tagetes erecta L. -- accepted -- Aztec marigold, French marigold
  Tagetes fragrantissima Sessé & Moc. -- not accepted
  Tagetes glandulifera Schrank -- not accepted
  Tagetes glandulosa Schrank ex Link -- not accepted
  Tagetes lemmonii A. Gray -- accepted -- Lemmon's marigold
  Tagetes lucida Cav. -- accepted -- sweetscented marigold
  Tagetes major Gaertn. -- not accepted
  Tagetes micrantha Cav. -- accepted -- licorice marigold
  Tagetes minima L. -- accepted -- miniature marigold
  Tagetes minuta L. -- accepted -- muster John Henry, wild marigold, marigold, stinkweed
  Tagetes palmeri A. Gray -- not accepted
  Tagetes papposa Vent. -- not accepted
  Tagetes patula L. -- not accepted -- French marigold
  Tagetes porophylla Vell. -- not accepted
  Tagetes pusilla Kunth -- not accepted -- lesser marigold
  Tagetes remotiflora Kunze -- not accepted
  Tagetes rotundifolia Mill. -- not accepted
  Tagetes signata Bartling -- not accepted
  Tagetes tenuifolia Millsp. -- not accepted
  Tamaulipa King & H. Rob. -- accepted -- boneset
  Tamaulipa azurea (DC.) King & H. Rob. -- accepted -- blue boneset
  Tanacetum L. -- accepted -- tansy
  Tanacetum balsamita L. -- accepted -- costmary
  Tanacetum bipinnatum (L.) Sch. Bip. -- accepted -- Lake Huron tansy, camphor tansy
  Tanacetum bipinnatum ssp. bipinnatum (L.) Sch. Bip. -- not accepted -- Lake Huron tansy
  Tanacetum bipinnatum ssp. huronense (Nutt.) Breitung -- not accepted -- Lake Huron tansy
  Tanacetum boreale Fisch. ex DC. -- not accepted
  Tanacetum camphoratum Less. -- not accepted -- camphor tansy
  Tanacetum canum D.C. Eaton -- not accepted
  Tanacetum capitatum (Nutt.) Torr. & A. Gray -- not accepted
  Tanacetum cinerariifolium (Trevir.) Sch. Bip. -- not accepted
  Tanacetum coccineum (Willd.) Grierson -- accepted -- pyrethum daisy
  Tanacetum compactum H.M. Hall -- not accepted
  Tanacetum corymbosum (L.) Sch. Bip. -- accepted -- corymbflower tansy
  Tanacetum diversifolium D.C. Eaton -- not accepted
  Tanacetum douglasii DC. -- not accepted
  Tanacetum huronense Nutt. -- not accepted
  Tanacetum huronense var. bifarium Fernald -- not accepted
  Tanacetum huronense var. floccosum Raup -- not accepted
  Tanacetum huronense var. johannense Fernald -- not accepted
  Tanacetum huronense var. terrae-novae Fernald -- not accepted
  Tanacetum nuttallii Torr. & A. Gray -- not accepted
  Tanacetum parthenium (L.) Sch. Bip. -- accepted -- feverfew
  Tanacetum potentilloides (A. Gray) A. Gray -- not accepted
  Tanacetum potentilloides var. nitrophilum Cronquist -- not accepted
  Tanacetum serotinum (L.) Sch. Bip. -- not accepted
  Tanacetum simplex A. Nelson -- not accepted
  Tanacetum suaveolens (Pursh) Hook. -- not accepted
  Tanacetum vulgare L. -- accepted -- common tansy, tansy, golden-buttons, hierba lombriguera, garden tansy
  Tanacetum vulgare var. crispum DC. -- not accepted
  Taraxacum F.H. Wigg. -- accepted -- dandelion
  Taraxacum alaskanum Rydb. -- accepted
  Taraxacum ambigens Fernald -- not accepted
  Taraxacum ambigens var. flutius Fernald -- not accepted
  Taraxacum amphiphron Böcher -- not accepted
  Taraxacum arcticum (Trautv.) Dahlst. -- not accepted
  Taraxacum arctogenum Dahlst. -- not accepted
  Taraxacum atroglaucum M.P. Christ. -- not accepted
  Taraxacum brachyceras Dahlst. -- not accepted
  Taraxacum californicum Munz & I.M. Johnst. -- accepted -- California dandelion, California taraxacum
  Taraxacum campylodes G.E. Haglund -- not accepted
  Taraxacum carneocoloratum A. Nelson -- accepted -- fleshy dandelion
  Taraxacum carthamopsis A.E. Porsild -- not accepted
  Taraxacum ceratophorum (Ledeb.) DC. -- accepted -- common dandelion, woolbearing dandelion
  Taraxacum croceum auct. non Dahlst. -- not accepted
  Taraxacum curvidens M.P. Christ. -- not accepted
  Taraxacum cyclocentrum M.P. Christ. -- not accepted
  Taraxacum dahlstedtii Lindb. f. -- not accepted
  Taraxacum davidssonii M.P. Christ. -- not accepted
  Taraxacum devians Dahlst. -- not accepted
  Taraxacum dilutisquameum M.P. Christ. -- not accepted
  Taraxacum disseminatum G.E. Haglund -- not accepted
  Taraxacum dumetorum Greene -- not accepted
  Taraxacum eriophorum Rydb. -- not accepted -- woolbearing dandelion
  Taraxacum erythrospermum Andrz. ex Besser -- accepted -- rock dandelion
  Taraxacum eurylepium Dahlst. -- not accepted
  Taraxacum firmum Dahlst. -- not accepted
  Taraxacum holmenianum Sahlin -- accepted
  Taraxacum hyparcticum Dahlst. -- accepted
  Taraxacum hyperboreum Dahlst. -- not accepted
  Taraxacum integratum G.E. Haglund -- not accepted
  Taraxacum islandiciforme Dahlst. -- not accepted
  Taraxacum kamtschaticum Dahlst. -- not accepted
  Taraxacum kok-saghyz auct. non Rodin -- not accepted
  Taraxacum lacerum Greene -- not accepted
  Taraxacum lacistophyllum (Dahlst.) Raunk. -- not accepted
  Taraxacum laevigatum (Willd.) DC. -- not accepted -- rock dandelion, red-seed dandelion
  Taraxacum lapponicum Kihlm. ex Hand.-Maz. -- accepted -- showy dandelion
  Taraxacum lateritium Dahlst. -- not accepted
  Taraxacum latilobum DC. -- accepted -- broad-lobe dandelion
  Taraxacum latispinulosum M.P. Christ. -- not accepted
  Taraxacum laurentianum Fernald -- accepted -- St. Lawrence dandelion, pissenlit du Saint-Laurent
  Taraxacum longii Fernald -- not accepted
  Taraxacum lyratum (Ledeb.) DC. -- not accepted -- harp dandelion, alpine dandelion, rock dandelion
  Taraxacum mackenziense A.E. Porsild -- not accepted
  Taraxacum malteanum Dahlst. -- not accepted
  Taraxacum maurolepium G.E. Haglund -- not accepted
  Taraxacum mitratum G.E. Haglund -- not accepted
  Taraxacum multesimum G.E. Haglund -- not accepted
  Taraxacum naevosum Dahlst. -- not accepted
  Taraxacum officinale F.H. Wigg. -- accepted -- common dandelion, blowball, faceclock, dandelion
  Taraxacum officinale ssp. ceratophorum (Ledeb.) Schinz ex Thell. -- not accepted -- common dandelion, fleshy dandelion, horned dandelion, rough dandelion
  Taraxacum officinale ssp. officinale F.H. Wigg. -- accepted -- common dandelion, lesser hawkbit, wandering dandelion
  Taraxacum officinale ssp. vulgare (Lam.) Schinz & R. Keller -- not accepted -- common dandelion
  Taraxacum officinale var. palustre (Lyons) Blytt -- not accepted
  Taraxacum olympicum G.N. Jones -- not accepted
  Taraxacum ovinum Rydb. -- not accepted
  Taraxacum palustre (Lyons) Symons -- accepted -- marsh dandelion
  Taraxacum palustre var. vulgare (Lam.) Fernald -- not accepted
  Taraxacum paucisquamosum M. Peck -- not accepted
  Taraxacum pellianum A.E. Porsild -- not accepted
  Taraxacum phymatocarpum J. Vahl -- accepted -- northern dandelion
  Taraxacum pleniflorum M.P. Christ. -- not accepted
  Taraxacum pseudonorvegicum Dahlst. -- not accepted
  Taraxacum pumilum Dahlst. -- not accepted
  Taraxacum purpuridens Dahlst. -- not accepted
  Taraxacum retroflexum Lindb. f. -- not accepted
  Taraxacum rhodolepis Dahlst. -- not accepted
  Taraxacum scanicum Dahlst. -- not accepted
  Taraxacum scopulorum (A. Gray) Rydb. -- accepted -- harp dandelion
  Taraxacum sibiricum auct. non Dahlst. -- not accepted
  Taraxacum spectabile Dahlst. -- not accepted -- showy dandelion
  Taraxacum torngatense Fernald -- not accepted
  Taraxacum trigonolobum Dahlst. -- accepted
  Taraxacum turfosum (Sch. Bip.) Soest -- not accepted
  Taraxacum umbrinum Dahlst. -- not accepted
  Taraxacum undulatum Lindb. f. & Marklund -- not accepted
  Taraxacum vagans G.E. Haglund -- not accepted
  Taraxacum vulgare Lam. -- not accepted
  Taraxacum xanthostigma Lindb. f. -- not accepted
  Telanthophora H. Rob. & Brettell -- accepted
  Telanthophora grandifolia (Less.) H. Rob. & Brettell -- accepted
  Tephroseris (Rchb.) Rchb. -- accepted -- groundsel
  Tephroseris atropurpurea (Ledeb.) Holub -- not accepted -- arctic groundsel
  Tephroseris atropurpurea ssp. atropurpurea (Ledeb.) Holub -- not accepted
  Tephroseris atropurpurea ssp. frigida (Richardson) A. Löve & D. Löve -- not accepted
  Tephroseris atropurpurea ssp. tomentosa (Kjellm.) A. Löve & D. Löve -- not accepted
  Tephroseris frigida (Richardson) Holub -- accepted
  Tephroseris integrifolia (L.) Holub -- accepted
  Tephroseris integrifolia ssp. atropurpurea (Ledeb.) B. Nord. -- accepted -- arctic groundsel
  Tephroseris kjellmanii (A.E. Porsild) Holub -- accepted -- Kjellman's groundsel
  Tephroseris lindstroemii (Ostenf.) A. Löve & D. Löve -- accepted -- fuscate groundsel
  Tephroseris palustris (L.) Reichenbach -- accepted -- marsh fleabane
  Tephroseris tundricola (Tolm.) Holub -- accepted
  Tephroseris tundricola var. lindstroemii (Ostenf.) V. Yu. -- not accepted
  Tephroseris yukonensis (A.E. Porsild) Holub -- accepted -- Yukon groundsel
  Tepion alatum (L.) Britton -- not accepted
  Tessaria sericea (Nutt.) Shinners -- not accepted
  Tetradymia DC. -- accepted -- horsebrush, tetradymia
  Tetradymia argyraea Munz & Roos -- accepted -- striped cottonthorn, striped horsebrush
  Tetradymia axillaris A. Nelson -- accepted -- longspine horsebrush
  Tetradymia axillaris var. axillaris A. Nelson -- accepted -- longspine horsebrush
  Tetradymia axillaris var. longispina (M.E. Jones) Strother -- accepted -- longspine horsebrush
  Tetradymia canescens DC. -- accepted -- spineless horsebrush, gray horsebrush
  Tetradymia canescens var. inermis (Rydb.) Payson -- not accepted
  Tetradymia comosa A. Gray -- accepted -- hairy horsebrush
  Tetradymia comosa ssp. tetrameres S.F. Blake -- not accepted
  Tetradymia filifolia Greene -- accepted -- threadleaf horsebrush
  Tetradymia glabrata Torr. & A. Gray -- accepted -- littleleaf horsebrush
  Tetradymia nuttallii Torr. & A. Gray -- accepted -- Nuttall's horsebrush
  Tetradymia ramosissima Torr. -- not accepted
  Tetradymia spinosa Hook. & Arn. -- accepted -- shortspine horsebrush, spiny horsebrush
  Tetradymia spinosa var. longispina M.E. Jones -- not accepted
  Tetradymia stenolepis Greene -- accepted -- Mojave cottonthorn, Mojave horsebrush
  Tetradymia tetrameres (S.F. Blake) Strother -- accepted -- fourpart horsebrush, four-part horsebrush
  Tetragonotheca L. -- accepted -- nerveray
  Tetragonotheca helianthoides L. -- accepted -- pineland nerveray
  Tetragonotheca ludoviciana (Torr. & A. Gray) A. Gray ex H.M. Hall -- accepted -- Louisiana nerveray
  Tetragonotheca repanda (Buckley) Small -- accepted -- showy nerveray
  Tetragonotheca texana Engelm. & A. Gray ex A. Gray -- accepted -- squarebud daisy
  Tetramolopium Nees -- accepted -- tetramolopium
  Tetramolopium arbusculum (A. Gray) Sherff -- not accepted
  Tetramolopium arenarium (A. Gray) Hillebr. -- accepted -- Maui tetramolopium
  Tetramolopium arenarium ssp. arenarium (A. Gray) Hillebr. -- accepted -- Maui tetramolopium
  Tetramolopium arenarium ssp. laxum Lowrey -- accepted -- Maui tetramolopium
  Tetramolopium arenarium var. arenarium (A. Gray) Hillebr. -- accepted -- Maui tetramolopium
  Tetramolopium arenarium var. confertum Sherff -- accepted -- Maui tetramolopium
  Tetramolopium arenarium var. dentatum Hillebr. -- not accepted
  Tetramolopium calcisabulorum (H. St. John) H. St. John -- not accepted
  Tetramolopium capillare (Gaudich.) H. St. John -- accepted -- pamakani
  Tetramolopium consanguineum (A. Gray) Hillebr. -- accepted -- forest tetramolopium
  Tetramolopium consanguineum ssp. consanguineum (A. Gray) Hillebr. -- accepted -- forest tetramolopium
  Tetramolopium consanguineum ssp. leptophyllum (Sherff) Lowrey -- accepted -- forest tetramolopium, Kauai tetramolopium
  Tetramolopium conyzoides (A. Gray) Hillebr. -- accepted -- smallhead tetramolopium
  Tetramolopium conyzoides var. dentatum (H. Mann) Sherff -- not accepted
  Tetramolopium filiforme Sherff -- accepted -- ridgetop tetramolopium
  Tetramolopium filiforme var. filiforme Sherff -- accepted -- ridgetop tetramolopium
  Tetramolopium filiforme var. polyphyllum (Sherff) Lowrey -- accepted -- ridgetop tetramolopium
  Tetramolopium humile (A. Gray) Hillebr. -- accepted -- alpine tetramolopium
  Tetramolopium humile ssp. haleakalae Lowrey -- accepted -- Haleakala tetramolopium
  Tetramolopium humile ssp. humile (A. Gray) Hillebr. -- accepted -- alpine tetramolopium
  Tetramolopium humile ssp. humile var. humile (A. Gray) Hillebr. -- not accepted -- alpine tetramolopium
  Tetramolopium humile ssp. humile var. sublaeve Sherff -- not accepted -- alpine tetramolopium
  Tetramolopium humile var. humile (A. Gray) Hillebr. -- accepted -- alpine tetramolopium
  Tetramolopium humile var. skottsbergii Sherff -- not accepted
  Tetramolopium humile var. sublaeve Sherff -- accepted -- alpine tetramolopium
  Tetramolopium lepidotum (Less.) Sherff -- accepted -- Waianae Range tetramolopium
  Tetramolopium lepidotum ssp. arbusculum (A. Gray) Lowrey -- accepted -- Waianae Range tetramolopium
  Tetramolopium lepidotum ssp. lepidotum (Less.) Sherff -- accepted -- Waianae Range tetramolopium
  Tetramolopium lepidotum var. luxurians (Hillebr.) Sherff -- not accepted
  Tetramolopium polyphyllum Sherff -- not accepted
  Tetramolopium remyi (A. Gray) Hillebr. -- accepted -- Awalua Ridge tetramolopium
  Tetramolopium rockii Sherff -- accepted -- dune tetramolopium
  Tetramolopium rockii var. calcisabulorum (H. St. John) Lowrey -- accepted -- dune tetramolopium
  Tetramolopium rockii var. rockii Sherff -- accepted -- dune tetramolopium
  Tetramolopium sylvae Lowrey -- accepted -- seacliff tetramolopium
  Tetramolopium tenerrimum (Less.) Nees -- accepted -- Oahu tetramolopium
  Tetraneuris Greene -- accepted -- four-nerve daisy
  Tetraneuris acaulis (Pursh) Greene -- accepted -- stemless four-nerve daisy, stemless actinea, stemless four-nerve-daisy, stemless hymenoxys
  Tetraneuris acaulis var. acaulis (Pursh) Greene -- accepted -- stemless four-nerve daisy, stemless four-nerve-daisy, stemless bitterweed
  Tetraneuris acaulis var. arizonica (Greene) K.F. Parker -- accepted -- Arizona four-nerve daisy, stemless four-nerve daisy
  Tetraneuris acaulis var. caespitosa A. Nelson -- accepted -- caespitose four-nerve daisy
  Tetraneuris acaulis var. epunctata (A. Nelson) Kartesz & Gandhi -- accepted -- stemless four-nerve daisy
  Tetraneuris acaulis var. nana (S.L. Welsh) Kartesz & Gandhi -- not accepted -- stemless four-nerve daisy
  Tetraneuris argentea (A. Gray) Greene -- accepted -- perkysue
  Tetraneuris brandegeei (Porter ex A. Gray) K.F. Parker -- not accepted -- Brandegee's four-nerve daisy
  Tetraneuris brevifolia Greene -- not accepted
  Tetraneuris depressa (Torr. & A. Gray ex A. Gray) Greene -- not accepted -- flat four-nerve daisy
  Tetraneuris epunctata A. Nelson -- not accepted
  Tetraneuris fastigiata Greene -- not accepted
  Tetraneuris glabra (Nutt.) Greene -- not accepted
  Tetraneuris grandiflora (Torr. & A. Gray ex A. Gray) K.F. Parker -- not accepted -- graylocks four-nerve daisy
  Tetraneuris herbacea Greene -- accepted -- eastern fournerved daisy
  Tetraneuris ivesiana Greene -- accepted -- Ives' fournerved daisy, Ives' four-nerve-daisy
  Tetraneuris linearifolia (Hook.) Greene -- accepted -- fineleaf fournerved daisy, slimleaf actinea
  Tetraneuris linearifolia var. arenicola Bierner -- accepted -- fineleaf fournerved daisy
  Tetraneuris linearifolia var. linearifolia (Hook.) Greene -- accepted -- fineleaf fournerved daisy
  Tetraneuris mancosensis A. Nelson -- not accepted
  Tetraneuris pilosa Cockerell -- not accepted
  Tetraneuris scaposa (DC.) Greene -- accepted -- stemmy four-nerve daisy
  Tetraneuris scaposa var. argyrocaulon (K.F. Parker) K.F. Parker -- accepted -- stemmy four-nerve daisy
  Tetraneuris scaposa var. linearis (Nutt.) Parker -- not accepted -- stemmy four-nerve daisy, plains tetraneuris
  Tetraneuris scaposa var. scaposa (DC.) Greene -- accepted -- stemmy four-nerve daisy, villous four-nerve daisy
  Tetraneuris scaposa var. villosa (Shinners) Shinners -- not accepted -- villous four-nerve daisy, villous hymenoxys
  Tetraneuris simplex A. Nelson -- not accepted
  Tetraneuris stenophylla Rydb. -- not accepted
  Tetraneuris torreyana (Nutt.) Greene -- accepted -- Torrey's four-nerve daisy, stone rubberweed, flat four-nerve daisy
  Tetraneuris turneri (K.F. Parker) K.F. Parker -- accepted -- Turner's four-nerve daisy
  Tetraneuris verdiensis R.A. Denham & B.L. Turner -- accepted
  Thelechitonia gracilis (Rich.) H. Rob. & Cuatrec. -- not accepted
  Thelechitonia trilobata (L.) H. Rob. & Cuatrec. -- not accepted
  Thelesperma Less. -- accepted -- greenthread
  Thelesperma ambiguum A. Gray -- accepted -- Colorado greenthread
  Thelesperma burridgeanum (Regel, Korn. & Rach.) S.F. Blake -- accepted -- Burridge's greenthread
  Thelesperma caespitosum Dorn -- not accepted -- low greenthread
  Thelesperma curvicarpum T.E. Melchert -- not accepted -- Edwards Plateau greenthread
  Thelesperma filifolium (Hook.) A. Gray -- accepted -- stiff greenthread, plains greenthread, greenthread
  Thelesperma filifolium var. filifolium (Hook.) A. Gray -- not accepted -- stiff greenthread
  Thelesperma filifolium var. intermedium (Rydb.) Shinners -- not accepted -- stiff greenthread
  Thelesperma flavodiscum (Shinners) B.L. Turner -- accepted -- East Texas greenthread
  Thelesperma fraternum Shinners -- not accepted
  Thelesperma gracile (Torr.) A. Gray -- not accepted
  Thelesperma intermedium Rydb. -- not accepted
  Thelesperma longipes A. Gray -- accepted -- longstalk greenthread, long-stalk greenthread, rayless greenthread
  Thelesperma marginatum Rydb. -- not accepted
  Thelesperma megapotamicum (Spreng.) Kuntze -- accepted -- Hopi tea greenthread, green threads
  Thelesperma megapotamicum var. ambiguum (A. Gray) Shinners -- not accepted
  Thelesperma nuecense B.L. Turner -- accepted -- Rio Grande greenthread
  Thelesperma pubescens Dorn -- not accepted -- hairy greenthread
  Thelesperma simplicifolium A. Gray -- accepted -- slender greenthread, Edwards Plateau greenthread
  Thelesperma subnudum A. Gray -- accepted -- Navajo tea, hairy greenthread, low greenthread, Navajo-tea, sand fringedpod
  Thelesperma subnudum var. alpinum S.L. Welsh -- not accepted
  Thelesperma subnudum var. caespitosum (Dorn) S.L. Welsh -- not accepted
  Thelesperma subnudum var. marginatum (Rydb.) T.E. Melchert ex Cronquist -- not accepted -- Navajo tea, greenthread, Navajo-tea
  Thelesperma subnudum var. subnudum A. Gray -- not accepted -- Navajo tea
  Thelesperma trifidum (Poir.) Britton -- not accepted
  Thurovia Rose -- accepted -- thurovia
  Thurovia triflora Rose -- accepted -- threeflower snakeweed
  Thymophylla Lag. -- accepted -- pricklyleaf, thymophylla
  Thymophylla acerosa (DC.) Strother -- accepted -- pricklyleaf dogweed, prickleaf dogweed, Texas dogweed
  Thymophylla aurea (A. Gray) Greene ex Britton -- accepted -- manyawn pricklyleaf
  Thymophylla aurea var. aurea (A. Gray) Greene ex Britton -- accepted -- manyawn pricklyleaf
  Thymophylla aurea var. polychaeta (A. Gray) Strother -- accepted -- manyawn pricklyleaf
  Thymophylla concinna (A. Gray) Strother -- accepted -- Sonoran pricklyleaf
  Thymophylla micropoides (DC.) Strother -- accepted -- woolly pricklyleaf
  Thymophylla pentachaeta (DC.) Small -- accepted -- fiveneedle pricklyleaf, five-needle pricklyleaf
  Thymophylla pentachaeta var. belenidium (DC.) Strother -- accepted -- fiveneedle pricklyleaf, firehair dogweed
  Thymophylla pentachaeta var. hartwegii (A. Gray) Strother -- accepted -- Hartweg's pricklyleaf, common dogweed
  Thymophylla pentachaeta var. pentachaeta (DC.) Small -- accepted -- fiveneedle pricklyleaf, common dogweed
  Thymophylla pentachaeta var. puberula (Rydb.) Strother -- accepted -- fiveneedle pricklyleaf
  Thymophylla polychaeta A. Gray -- not accepted
  Thymophylla setifolia Lag. -- accepted -- Texas pricklyleaf
  Thymophylla setifolia var. greggii (A. Gray) Strother -- accepted -- Texas pricklyleaf
  Thymophylla setifolia var. radiata (A. Gray) Strother -- not accepted -- Texas pricklyleaf
  Thymophylla setifolia var. setifolia Lag. -- accepted -- Texas pricklyleaf
  Thymophylla tenuiloba (DC.) Small -- accepted -- bristleleaf pricklyleaf
  Thymophylla tenuiloba var. tenuiloba (DC.) Small -- accepted -- bristleleaf pricklyleaf
  Thymophylla tenuiloba var. texana (Cory) Strother -- accepted -- Texas bristleleaf, Texas dogbane
  Thymophylla tenuiloba var. treculii (A. Gray) Strother -- accepted -- Trecul's pricklyleaf
  Thymophylla tenuiloba var. wrightii (A. Gray) Strother -- accepted -- Wright's pricklyleaf
  Thymophylla tephroleuca (S.F. Blake) Strother -- accepted -- ashy pricklyleaf, ashy dogweed
  Tithonia Desf. ex Juss. -- accepted -- tithonia
  Tithonia argophylla D.C. Eaton -- not accepted
  Tithonia diversifolia (Hemsl.) A. Gray -- accepted -- tree marigold
  Tithonia rotundifolia (Mill.) S.F. Blake -- accepted -- clavel de muerto
  Tithonia speciosa (Hook.) Griseb. -- not accepted
  Tithonia thurberi A. Gray -- accepted -- Arizona sunflowerweed, Arizona sunflower weed
  Toiyabea R.P. Roberts, Urbatsch & Neubig -- accepted
  Toiyabea alpina (L.C. Anderson & Goodrich) R.P. Roberts, Urbatsch & Neubig -- accepted -- alpine serpentweed
  Tolpis Adans. -- accepted -- umbrella milkwort
  Tolpis barbata (L.) Gaertn. -- accepted -- European umbrella milkwort
  Tolpis umbellata Bertol. -- not accepted
  Tonestus A. Nelson -- accepted -- serpentweed, tonestus
  Tonestus aberrans (A. Nelson) G.L. Nesom & D. Morgan -- not accepted -- Idaho goldenweed
  Tonestus alpinus (L.C. Anderson & Goodrich) G.L. Nesom & D. Morgan -- not accepted -- alpine serpentweed, alpine goldenbush
  Tonestus eximius (H.M. Hall) A. Nelson & J.F. Macbr. -- accepted -- Lake Tahoe serpentweed, Tahoe goldenweed
  Tonestus graniticus (Tiehm & L.M. Shultz) G.L. Nesom & D. Morgan -- accepted -- granite serpentweed, granite goldenweed
  Tonestus kingii (D.C. Eaton) G.L. Nesom -- not accepted -- King's serpentweed
  Tonestus kingii var. barnebyana (S.L. Welsh & Goodrich) G.L. Nesom -- not accepted -- Barneby's serpentweed
  Tonestus kingii var. kingii (D.C. Eaton) G.L. Nesom -- not accepted -- King's serpentweed
  Tonestus lyallii (A. Gray) A. Nelson -- accepted -- Lyall's goldenweed, alpine goldenweed
  Tonestus microcephalus (Cronquist) G.L. Nesom & D. Morgan -- not accepted -- smallhead heathgoldenrod
  Tonestus peirsonii (D.D. Keck) G.L. Nesom & D. Morgan -- not accepted -- Peirson's serpentweed
  Tonestus pygmaeus (Torr. & A. Gray) A. Nelson -- accepted -- pygmy goldenweed
  Townsendia Hook. -- accepted -- Townsend daisy, townsendia
  Townsendia alpigena Piper -- not accepted -- Wyoming Townsend daisy
  Townsendia alpigena var. alpigena Piper -- not accepted -- Wyoming Townsend daisy
  Townsendia alpigena var. caelilinensis (S.L. Welsh) Kartesz & Gandhi -- not accepted -- Wyoming Townsend daisy
  Townsendia alpigena var. minima (Eastw.) Dorn -- not accepted -- Wyoming Townsend daisy
  Townsendia annua Beaman -- accepted -- annual Townsend daisy, annual Townsend-daisy
  Townsendia anomala Heiser -- not accepted
  Townsendia aprica S.L. Welsh & Reveal -- accepted -- last chance Townsend daisy, Last Chance townsendia
  Townsendia arizonica A. Gray -- not accepted
  Townsendia condensata Parry ex A. Gray -- accepted -- cushion Townsend daisy
  Townsendia condensata var. anomala (Heiser) Dorn -- not accepted -- cushion Townsend daisy
  Townsendia condensata var. condensata Parry ex A. Gray -- not accepted -- cushion Townsend daisy
  Townsendia eximia A. Gray -- accepted -- tall Townsend daisy, tall townsendia
  Townsendia exscapa (Richardson) Porter -- accepted -- stemless Townsend daisy, stemless townsend-daisy, stemless townsendia
  Townsendia fendleri A. Gray -- accepted -- Fendler's Townsend daisy
  Townsendia florifer (Hook.) A. Gray -- accepted -- showy Townsend daisy
  Townsendia florifer var. watsonii (A. Gray) Cronquist -- not accepted
  Townsendia florifera (Hook.) A. Gray -- not accepted -- showy Townsend daisy, showy townsendia
  Townsendia florifera var. watsonii (A. Gray) Cronquist -- not accepted
  Townsendia formosa Greene -- accepted -- smooth Townsend daisy, smooth townsend-daisy
  Townsendia glabella A. Gray -- accepted -- Gray's Townsend daisy
  Townsendia grandiflora Nutt. -- accepted -- largeflower Townsend daisy
  Townsendia gypsophila T.K. Lowrey & P.J. Knight -- accepted -- gypsum-loving Townsend daisy
  Townsendia hookeri Beaman -- accepted -- Hooker's Townsend daisy, Hooker's townsendia, Hooker's townsend-daisy
  Townsendia incana Nutt. -- accepted -- hoary Townsend daisy, hoary townsend-daisy, hoary townsendia
  Townsendia intermedia Rydb. -- not accepted
  Townsendia jonesii (Beaman) Reveal -- accepted -- Jones' Townsend daisy, Jones' townsendia
  Townsendia jonesii var. jonesii (Beaman) Reveal -- accepted -- Jones' Townsend daisy, Jones' townsendia
  Townsendia jonesii var. lutea S.L. Welsh -- not accepted
  Townsendia jonesii var. tumulosa Reveal -- not accepted -- Jones' Townsend daisy, Charleston townsendia
  Townsendia leptotes (A. Gray) Osterh. -- accepted -- common Townsend daisy, common townsendia
  Townsendia mensana M.E. Jones -- accepted -- table Townsend daisy
  Townsendia mensana var. jonesii Beaman -- not accepted
  Townsendia microcephala Dorn -- accepted -- smallheaded Townsend daisy
  Townsendia minima Eastw. -- accepted -- Wyoming Townsend daisy
  Townsendia montana M.E. Jones -- accepted -- Wyoming Townsend daisy
  Townsendia montana var. caelilinensis S.L. Welsh -- not accepted
  Townsendia montana var. minima (Eastw.) Beaman -- not accepted
  Townsendia nuttallii Dorn -- not accepted -- Nuttall's Townsend daisy
  Townsendia parryi D.C. Eaton -- accepted -- Parry's Townsend daisy, Parry's townsendia
  Townsendia pinetorum Greene ex A. Nelson -- not accepted
  Townsendia rothrockii A. Gray ex Rothr. -- accepted -- Rothrock's Townsend daisy, Rothrock's townsendia
  Townsendia scapigera D.C. Eaton -- accepted -- tufted Townsend daisy, ground townsendia
  Townsendia sericea Hook. -- not accepted
  Townsendia sericea var. leptotes A. Gray -- not accepted
  Townsendia smithii L.M. Shultz & A.H. Holmgren -- accepted -- Black Rock Townsend daisy, Black Rock townsend-daisy
  Townsendia spathulata Nutt. -- accepted -- sword Townsend daisy
  Townsendia strigosa Nutt. -- accepted -- hairy Townsend daisy, hairy Townsend-daisy, hairy townsendia
  Townsendia texensis Larsen -- accepted -- Texas Townsend daisy, Texas townsendia
  Townsendia vreelandii Rydb. -- not accepted
  Townsendia wrightii (A. Gray) A. Gray -- not accepted
  Tracyina S.F. Blake -- accepted -- Indian headdress
  Tracyina rostrata S.F. Blake -- accepted -- Indian headdress
  Tragopogon L. -- accepted -- goatsbeard, salsify
  Tragopogon dubius Scop. -- accepted -- yellow salsify, goat's beard, salsifis majeur, western goat's beard, western salsify, wild oysterplant, yellow goat's beard, salsify, common salsify, goatsbeard, meadow goat's-beard
  Tragopogon dubius ssp. major (Jacq.) Voll. -- not accepted
  Tragopogon floccosus Waldst. & Kit. -- accepted -- woolly goatsbeard
  Tragopogon hybridus L. -- accepted -- pasture goatsbeard
  Tragopogon lamottei Rouy -- not accepted
  Tragopogon major Jacq. -- not accepted
  Tragopogon mirabilis Rouy -- accepted -- Ontario goatsbeard, Ontario goat's-beard
  Tragopogon mirus Ownbey -- accepted -- remarkable goatsbeard, remarkable goat's-beard
  Tragopogon miscellus Ownbey -- accepted -- Moscow salsify, hybrid goat's-beard
  Tragopogon orientalis L. -- not accepted
  Tragopogon porrifolius L. -- accepted -- salsify, purple salsify, common salsify, goatsbeard
  Tragopogon pratensis L. -- accepted -- Jack-go-to-bed-at-noon, meadow salsify
  Tragopogon pratensis ssp. orientalis (L.) Celak. -- not accepted -- oriental salsify
  Tragopogon pratensis ssp. pratensis L. -- not accepted -- Jack-go-to-bed-at-noon
  Tragopogon X crantzii Dichlt. -- accepted -- Crantz's salsify
  Tragopogon X neohybridus Farw. -- accepted -- newhybrid salsify
  Trichocoronis A. Gray -- accepted -- bugheal
  Trichocoronis riparia (Greene) Greene -- not accepted -- river bugheal
  Trichocoronis rivularis A. Gray -- not accepted -- Rio Grande bugheal
  Trichocoronis wrightii (Torr. & A. Gray) A. Gray -- accepted -- limestone bugheal, river bugheal
  Trichocoronis wrightii var. wrightii (Torr. & A. Gray) A. Gray -- not accepted
  Trichoptilium A. Gray -- accepted -- trichoptilium
  Trichoptilium incisum (A. Gray) A. Gray -- accepted -- yellowdome, yellow dome, yellowhead
  Tridax L. -- accepted -- tridax
  Tridax accedens S.F. Blake -- not accepted
  Tridax procumbens L. -- accepted -- coatbuttons, cadillo chisaca, tridax, coat buttons
  Trilisa odoratissima (J.F. Gmel.) Cass. -- not accepted
  Trilisa paniculata (J.F. Gmel.) Cass. -- not accepted
  Trimorpha acris auct. non (L.) Gray -- not accepted -- bitter boreal daisy
  Trimorpha acris var. asteroides (Andrz. ex Besser) G.L. Nesom -- not accepted
  Trimorpha acris var. debilis (A. Gray) G.L. Nesom -- not accepted
  Trimorpha acris var. kamtschatica (DC.) G.L. Nesom -- not accepted
  Trimorpha borealis Vierh. -- not accepted
  Trimorpha elata (Hook.) G.L. Nesom -- not accepted
  Trimorpha elongata (Ledeb.) Vierh. -- not accepted
  Trimorpha lonchophylla (Hook.) G.L. Nesom -- not accepted
  Trimorpha lonchophylla var. laurentiana (Victorin) Kartesz & Gandhi -- not accepted -- shortray boreal daisy
  Trimorpha lonchophylla var. lonchophylla (Hook.) Nesom -- not accepted -- spearleaf fleabane
  Trimorpha scotteri (B. Boivin) G.L. Nesom -- not accepted
  Triniteurybia Brouillet, Urbatsch & R.P. Roberts -- accepted
  Triniteurybia aberrans (A. Nelson) Brouillet, Urbatsch & R.P. Roberts -- accepted -- Idaho goldenweed
  Tripleurospermum Sch. Bip. -- accepted -- mayweed
  Tripleurospermum inodorum (L.) Sch. Bip. -- accepted -- scentless false mayweed
  Tripleurospermum maritima (L.) W.D.J. Koch -- accepted -- false mayweed
  Tripleurospermum maritima ssp. maritima (L.) W.D.J. Koch -- accepted -- false mayweed, mayweed
  Tripleurospermum maritima ssp. phaeocephala (Rupr.) Hämet-Ahti -- accepted -- false mayweed
  Tripleurospermum perforata (Mérat) M. Lainz -- not accepted -- scentless false mayweed
  Tripleurospermum phaeocephalum (Rupr.) Pobed. -- not accepted
  Tripolium Nees -- accepted -- sea aster
  Tripolium angustum Lindl. -- not accepted
  Tripolium frondosum Nutt. -- not accepted
  Tripolium occidentale Nutt. -- not accepted
  Tripolium oregonum Nutt. -- not accepted
  Tripolium pannonicum (Jacq.) Dobrocz. -- accepted -- sea aster
  Tripolium subulatum var. parviflorum Nees -- not accepted
  Trixis P. Br. -- accepted -- threefold, trixis
  Trixis californica Kellogg -- accepted -- American threefold, California trixis, American trixis
  Trixis californica var. californica Kellogg -- accepted -- American threefold, California threefold
  Trixis inula Crantz -- accepted -- tropical threefold
  Trixis radialis (L.) Kuntze -- not accepted
  Troximon apargioides Less. -- not accepted
  Troximon aurantiacum Hook. -- not accepted
  Troximon glaucum Pursh -- not accepted
  Troximon glaucum var. dasycephalum Torr. & A. Gray -- not accepted
  Troximon grandiflorum Nutt. -- not accepted
  Troximon parviflorum Nutt. -- not accepted
  Tuckermannia gigantea (Kellogg) M.E. Jones -- not accepted
  Tuckermannia maritima Nutt. -- not accepted
  Tussilago L. -- accepted -- coltsfoot
  Tussilago farfara L. -- accepted -- coltsfoot, colts foot
  Tussilago nutans L. -- not accepted
  Unamia alba (Nutt.) Rydb. -- not accepted
  Unamia lutescens (Lindl. ex DC.) Rydb. -- not accepted
  Uropappus Nutt. -- accepted -- silverpuffs, Uropappus
  Uropappus lindleyi (DC.) Nutt. -- accepted -- Lindley's silverpuffs
  Uropappus linearifolius Nutt. -- not accepted
  Urospermum Scop. -- accepted -- urospermum
  Urospermum picroides (L.) Scop. ex F.W. Schmidt -- accepted -- prickly goldenfleece
  Vanclevea Greene -- not accepted -- vanclevea
  Vanclevea stylosa (Eastw.) Greene -- not accepted -- pillar false gumweed
  Varilla A. Gray -- accepted -- varilla
  Varilla texana A. Gray -- accepted -- Texas varilla
  Venegasia DC. -- accepted -- venegasia
  Venegasia carpesioides DC. -- accepted -- canyon sunflower
  Venidium Less. -- accepted -- venidium
  Venidium fastuosum (Jacq.) Stapf -- accepted -- monarch of the veld
  Verbesina L. -- accepted -- crownbeard
  Verbesina alata L. -- accepted -- capitaneja
  Verbesina alba L. -- not accepted
  Verbesina alternifolia (L.) Britton ex Kearney -- accepted -- wingstem
  Verbesina aristata (Elliot) A. Heller -- accepted -- coastal plain crownbeard, coastalplain crownbeard
  Verbesina chapmanii J.R. Coleman -- accepted -- Chapman's crownbeard
  Verbesina dissita A. Gray -- accepted -- bigleaf crownbeard, big-leaved crown-beard, big-leaved crownbeard
  Verbesina encelioides (Cav.) Benth. & Hook. f. ex A. Gray -- accepted -- golden crownbeard
  Verbesina encelioides ssp. encelioides (Cav.) Benth. & Hook. f. ex A. Gray -- not accepted -- golden crownbeard
  Verbesina encelioides ssp. exauriculata (B.L. Rob. & Greenm.) J.R. Coleman -- not accepted -- golden crownbeard
  Verbesina encelioides var. exauriculata B.L. Rob. & Greenm. -- not accepted
  Verbesina exauriculata (B.L. Rob. & Greenm.) Cockerell -- not accepted
  Verbesina hastata Kellogg ex Curran -- accepted
  Verbesina helianthoides Michx. -- accepted -- gravelweed, gravelweed crownbeard
  Verbesina heterophylla (Chapm.) A. Gray -- accepted -- diverseleaf crownbeard
  Verbesina laciniata (Poir.) Nutt. -- not accepted
  Verbesina lavenia L. -- not accepted
  Verbesina lindheimeri B.L. Rob. & Greenm. -- accepted -- Lindheimer's crownbeard
  Verbesina longifolia (A. Gray) A. Gray -- accepted -- longleaf crownbeard, long-leaf crownbeard
  Verbesina microptera (DC.) Herter non DC. -- not accepted -- Texas crownbeard
  Verbesina microptera DC. -- accepted -- Texas crownbeard
  Verbesina microptera var. mollissima B.L. Rob. & Greenm. -- not accepted
  Verbesina nana (A. Gray) B.L. Rob. & Greenm. -- accepted -- dwarf crownbeard
  Verbesina nodiflora L. -- not accepted
  Verbesina nudicaulis (Nutt.) A. Gray -- not accepted
  Verbesina occidentalis (L.) Walter -- accepted -- yellow crownbeard
  Verbesina oreophila Woot. & Standl. -- accepted -- mountain crownbeard
  Verbesina pauciflora (Nutt.) Small non Hemsl. -- not accepted
  Verbesina podocephala A. Gray -- not accepted
  Verbesina prostrata L. -- not accepted
  Verbesina rothrockii B.L. Rob. & Greenm. -- accepted -- Rothrock's crownbeard
  Verbesina sinuata Elliot -- not accepted
  Verbesina texana Buckley -- not accepted
  Verbesina virginica L. -- accepted -- white crownbeard, Virginia crownbeard, iceweed
  Verbesina virginica var. insularis B.L. Rob. & Greenm. -- not accepted
  Verbesina virginica var. laciniata (Poir.) A. Gray -- not accepted -- white crownbeard
  Verbesina virginica var. virginica L. -- not accepted -- white crownbeard, maritime groundcherry
  Verbesina walteri Shinners -- accepted -- Carolina crownbeard
  Verbesina warei A. Gray -- not accepted
  Vernonia Schreb. -- accepted -- ironweed
  Vernonia aborigina Gleason -- not accepted
  Vernonia acaulis (Walter) Gleason -- accepted -- stemless ironweed
  Vernonia albicaulis Pers. -- not accepted -- Santa Maria
  Vernonia altissima Nutt. -- not accepted
  Vernonia altissima var. lilacina Clute -- not accepted
  Vernonia altissima var. taeniotricha S.F. Blake -- not accepted
  Vernonia angustifolia Michx. -- accepted -- tall ironweed
  Vernonia angustifolia ssp. angustifolia Michx. -- not accepted -- tall ironweed
  Vernonia angustifolia ssp. mohrii (S.B. Jones) S.B. Jones & Faust -- not accepted -- Mohr's ironweed
  Vernonia angustifolia ssp. scaberrima (Nutt.) S.B. Jones & Faust -- not accepted -- tall ironweed
  Vernonia angustifolia var. mohrii S.B. Jones -- not accepted
  Vernonia angustifolia var. scaberrima (Nutt.) A. Gray -- not accepted
  Vernonia anthelmintica (L.) Willd. -- accepted -- ironweed
  Vernonia arkansana DC. -- accepted -- Arkansas ironweed
  Vernonia baldwinii Torr. -- accepted -- Baldwin's ironweed, interior ironweed, western ironweed, ironweed
  Vernonia baldwinii ssp. baldwinii Torr. -- not accepted -- Baldwin's ironweed
  Vernonia baldwinii ssp. interior (Small) Faust -- not accepted -- interior ironweed
  Vernonia blodgettii Small -- accepted -- Florida ironweed
  Vernonia borinquensis Urb. -- not accepted -- Puerto Rico ironweed
  Vernonia cinerea (L.) Less. -- not accepted -- little ironweed
  Vernonia cinerea var. parviflora (Reinw.) DC. -- not accepted
  Vernonia crinita Raf. -- not accepted
  Vernonia fasciculata Michx. -- accepted -- prairie ironweed, western ironweed
  Vernonia fasciculata ssp. corymbosa (Schwein. ex Keating) S.B. Jones -- not accepted -- prairie ironweed, western ironweed
  Vernonia fasciculata ssp. fasciculata Michx. -- not accepted -- prairie ironweed
  Vernonia fasciculata var. corymbosa (Schwein. ex Keating) Daniels -- not accepted
  Vernonia flaccidifolia Small -- accepted -- Tennessee ironweed
  Vernonia galamensis (Cass.) Less. -- accepted -- ironweed
  Vernonia gigantea (Walter) Trel. -- accepted -- giant ironweed, tall ironweed
  Vernonia gigantea ssp. gigantea (Walter) Trel. -- not accepted -- giant ironweed
  Vernonia gigantea ssp. ovalifolia (Torr. & A. Gray) Urbatsch -- not accepted -- giant ironweed
  Vernonia glauca (L.) Willd. -- accepted -- broadleaf ironweed
  Vernonia harperi Gleason -- not accepted
  Vernonia interior Small -- not accepted
  Vernonia larseniae B.L. King & S.B. Jones -- accepted -- Larsen's ironweed
  Vernonia larsenii B.L. King & S.B. Jones -- not accepted -- Larsen's ironweed
  Vernonia lettermannii Engelm. ex A. Gray -- accepted -- narrowleaf ironweed, slimleaf ironweed
  Vernonia lindheimeri A. Gray & Engelm. -- accepted -- woolly ironweed
  Vernonia lindheimeri var. leucophylla Larsen -- not accepted
  Vernonia marginata (Torr.) Raf. -- accepted -- plains ironweed, ironplant
  Vernonia marginata var. tenuifolia (Small) Shinners -- not accepted
  Vernonia missurica Raf. -- accepted -- Missouri ironweed
  Vernonia noveboracensis (L.) Michx. -- accepted -- New York ironweed
  Vernonia noveboracensis var. tomentosa (Elliot) Britton -- not accepted
  Vernonia ovalifolia Torr. & A. Gray -- not accepted
  Vernonia pauciflora (Willd.) Less. -- not accepted
  Vernonia proctorii Urbatsch -- not accepted
  Vernonia pulchella Small -- accepted -- Georgia ironweed
  Vernonia recurva Gleason -- not accepted
  Vernonia scaberrima Nutt. -- not accepted
  Vernonia sericea Rich. -- not accepted -- longshoot
  Vernonia texana (A. Gray) Small -- accepted -- Texas ironweed
  Vernonia X concinna Gleason (pro sp.) -- accepted -- ironweed
  Vernonia X dissimilis Gleason (pro sp.) -- accepted -- ironweed
  Vernonia X georgiana Bartlett (pro sp.) -- accepted -- ironweed
  Vernonia X guadalupensis A. Heller (pro sp.) -- accepted -- Guadalupe ironweed
  Vernonia X illinoensis Gleason -- accepted -- Illinois ironweed
  Vernonia X peralta Daniels -- accepted -- ironweed
  Vernonia X recurva Gleason (pro sp.) -- accepted
  Vernonia X vulturina Shinners (pro sp.) -- accepted -- ironweed
  Vesicarpa Rydb. -- accepted
  Vesicarpa potentilloides (A. Gray) Rydb. -- not accepted
  Vesicarpa potentilloides var. nitrophilum (Cronquist) Kartesz -- not accepted
  Vesicarpa potentilloides var. potentilloides (A. Gray) Rydb. -- not accepted
  Vicoa auriculata auct. non Cass. -- not accepted
  Viguiera Kunth -- accepted -- goldeneye
  Viguiera annua (M.E. Jones) S.F. Blake -- not accepted
  Viguiera ciliata (B.L. Rob. & Greenm.) S.F. Blake -- not accepted
  Viguiera cordifolia A. Gray -- accepted -- heartleaf goldeneye, mountain goldeneye
  Viguiera deltoidea A. Gray -- accepted -- triangle goldeneye
  Viguiera deltoidea var. deltoidea A. Gray -- not accepted -- triangle goldeneye
  Viguiera deltoidea var. genuina S.F. Blake -- not accepted
  Viguiera deltoidea var. parishii (Greene) Vasey & Rose -- not accepted
  Viguiera dentata (Cav.) Spreng. -- accepted -- toothleaf goldeneye, sunflower goldeneye
  Viguiera dentata var. dentata (Cav.) Spreng. -- accepted -- toothleaf goldeneye
  Viguiera dentata var. lancifolia S.F. Blake -- accepted -- toothleaf goldeneye, lanceleaf goldeneye
  Viguiera laciniata A. Gray -- not accepted -- torhleaf goldeneye
  Viguiera longifolia (B.L. Rob. & Greenm.) S.F. Blake -- not accepted
  Viguiera longifolia var. annua (M.E. Jones) S.L. Welsh -- not accepted
  Viguiera ludens (Shinners) M.C. Johnst. -- not accepted
  Viguiera multiflora (Nutt.) S.F. Blake -- not accepted
  Viguiera multiflora var. macrocephala (Heiser) B.L. Turner -- not accepted
  Viguiera multiflora var. nevadensis (A. Nelson) S.F. Blake -- not accepted
  Viguiera ovalis S.F. Blake -- not accepted
  Viguiera parishii Greene -- not accepted -- Parish's goldeneye
  Viguiera phenax S.F. Blake -- accepted -- field goldeneye
  Viguiera porteri (A. Gray) S.F. Blake -- not accepted
  Viguiera reticulata S. Watson -- not accepted -- netvein goldeneye, Death Valley goldeneye
  Viguiera soliceps Barneby -- not accepted
  Viguiera stenoloba S.F. Blake -- accepted -- resinbush, skeletonleaf goldeneye
  Viguiera stenoloba var. chihuahuensis Butterwick -- not accepted -- Chihuahua resinbush
  Viguiera stenoloba var. stenoloba S.F. Blake -- accepted -- resinbush
  Viguiera triloba (A. Gray) J. Olsen -- not accepted -- yellow streamers, yellow-streamers
  Virgulaster ascendens (Lindl.) Semple -- not accepted
  Virgulaster bernardinus (H.M. Hall) Semple -- not accepted
  Virgulus adnatus (Nutt.) Reveal & Keener -- not accepted
  Virgulus campestris (Nutt.) Reveal & Keener -- not accepted
  Virgulus carolinianus (Walter) Reveal & Keener -- not accepted
  Virgulus concolor (L.) Reveal & Keener -- not accepted
  Virgulus ericoides (L.) Reveal & Keener -- not accepted
  Virgulus falcatus (Lindl.) Reveal & Keener -- not accepted
  Virgulus fendleri (A. Gray) Reveal & Keener -- not accepted
  Virgulus georgianus (Alexander) Semple -- not accepted
  Virgulus grandiflorus (L.) Reveal & Keener -- not accepted
  Virgulus novae-angliae (L.) Reveal & Keener -- not accepted
  Virgulus oblongifolius (Nutt.) Reveal & Keener -- not accepted
  Virgulus patens (Aiton) Reveal & Keener -- not accepted
  Virgulus patens var. georgianus (Alexander) Reveal & Keener -- not accepted
  Virgulus patens var. gracilis (Hook.) Reveal & Keener -- not accepted
  Virgulus patens var. patentissimus (Lindl. ex DC.) Reveal & Keener -- not accepted
  Virgulus patens var. phlogifolius (Muhl. ex Willd.) Reveal & Keener -- not accepted
  Virgulus pratensis (Raf.) Reveal & Keener -- not accepted
  Virgulus sericeus (Vent.) Reveal & Keener -- not accepted
  Virgulus walteri (Alexander) Reveal & Keener -- not accepted
  Virgulus X amethystinus (Nutt.) Reveal & Keener -- not accepted
  Virgulus yukonensis (Cronquist) Reveal & Keener -- not accepted
  Vittadinia remyi A. Gray -- not accepted
  Volutaria Cass. -- accepted
  Volutaria muricata (L.) Maire -- accepted -- Morocco knapweed
  Weberaster modestus (Lindl.) A. Löve & D. Löve -- not accepted
  Weberaster radulinus (A. Gray) Á. Löve & D. Löve -- not accepted
  Wedelia Jacq. -- accepted -- creepingoxeye, wedelia
  Wedelia acapulcensis Kunth -- accepted -- Acapulco wedelia
  Wedelia acapulcensis var. acapulcensis Kunth -- accepted
  Wedelia acapulcensis var. hispida auct. non (Kunth) Strother -- not accepted -- hairy wedelia
  Wedelia acapulcensis var. hispida (Kunth) Strother -- accepted -- hairy wedelia
  Wedelia carnosa Rich. -- not accepted
  Wedelia fruticosa Jacq. -- accepted -- coastal plain creepingoxeye, smallflower creepingoxeye, coastalplain creepingoxeye
  Wedelia glauca (Ortega) Hoffm. ex Hicken -- not accepted
  Wedelia gracilis Rich. -- not accepted
  Wedelia hispida auct. non Kunth -- not accepted
  Wedelia lanceolata DC. -- accepted -- riverbank creepingoxeye
  Wedelia reticulata DC. -- accepted -- manazanilla del monte
  Wedelia texana (A. Gray) B.L. Turner -- not accepted -- hairy wedelia
  Wedelia trilobata (L.) Hitchc. -- not accepted -- Bay Biscayne creeping oxeye, wedelia
  Whitneya A. Gray -- not accepted -- whitneya
  Whitneya dealbata A. Gray -- not accepted -- mock leopardbane
  Wilkesia A. Gray -- accepted -- iliau
  Wilkesia grayana Hillebr. -- not accepted
  Wilkesia gymnoxiphium A. Gray -- accepted -- iliau
  Wilkesia hobdyi H. St. John -- accepted -- dwarf iliau
  Willoughbya halei Small -- not accepted
  Willoughbya heterophylla Small -- not accepted
  Wollastonia DC. ex Decn. -- accepted
  Wollastonia biflora (L) DC -- not accepted
  Wootonella nana (A. Gray) Standl. -- not accepted
  Wyethia Nutt. -- accepted -- mule-ears, wyethia
  Wyethia amplexicaulis (Nutt.) Nutt. -- accepted -- mule-ears, mulesear wyethia, mule's ear wyethia
  Wyethia angustifolia (DC.) Nutt. -- accepted -- California compassplant
  Wyethia angustifolia var. foliosa (Congd.) H.M. Hall -- not accepted
  Wyethia arizonica A. Gray -- accepted -- Arizona mule-ears, Arizona mulesears
  Wyethia bolanderi (A. Gray) W.A. Weber -- not accepted -- Bolander's mule-ears
  Wyethia elata H.M. Hall -- not accepted -- Hall's mule-ears
  Wyethia glabra A. Gray -- accepted -- Coast Range mule-ears
  Wyethia helenioides (DC.) Nutt. -- accepted -- whitehead mule-ears
  Wyethia helianthoides Nutt. -- accepted -- sunflower mule-ears, whitehead wyethia
  Wyethia invenusta (Greene) W.A. Weber -- not accepted -- Coville's mule-ears
  Wyethia longicaulis A. Gray -- accepted -- Humboldt mule-ears
  Wyethia mollis A. Gray -- accepted -- woolly mule-ears, wooly wyethia
  Wyethia ovata Torr. & A. Gray ex Torr. -- not accepted -- southern mule-ears
  Wyethia reticulata Greene -- not accepted -- El Dorado mule-ears
  Wyethia scabra Hook. -- not accepted -- badlands mule-ears, badlands mulesears, badlands wyethia
  Wyethia scabra var. attenuata W.A. Weber -- not accepted -- badlands mule-ears, badlands mulesears
  Wyethia scabra var. canescens W.A. Weber -- not accepted -- badlands mule-ears, badlands mulesears
  Wyethia scabra var. scabra Hook. -- not accepted -- badlands mule-ears, badlands mulesears
  Wyethia X cusickii Piper (pro sp.) -- accepted -- Cusick's mulesears
  Wyethia X magna A. Nelson (pro sp.) -- accepted -- wyethia
  X Argyrautia Sherff -- accepted -- argyrautia
  X Argyrautia degeneri Sherff -- accepted -- Degener's argyrautia
  X Solidaster H.R. Wehrh. -- not accepted
  Xanthisma DC. -- accepted -- sleepydaisy, xanthium
  Xanthisma blephariphyllum (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted
  Xanthisma coloradoense (A. Gray) D.R. Morgan & R.L. Hartm. -- accepted
  Xanthisma gracile (Nutt.) D.R. Morgan & R.L. Hartm. -- accepted -- slender goldenweed
  Xanthisma grindelioides (Nutt.) D.R. Morgan & R.L. Hartm. -- accepted -- goldenweed, gumweed aster, rayless tansyaster
  Xanthisma grindelioides var. depressum (Maguire) D.R. Morgan & R.L. Hartm. -- accepted -- rayless tansyaster
  Xanthisma grindelioides var. grindelioides (Nutt.) D.R. Morgan & R.L. Hartm. -- accepted -- goldenweed, gumweed aster
  Xanthisma gypsophilum (B.L. Turner) D.R. Morgan & R.L. Hartm. -- accepted -- gypsum tansyaster
  Xanthisma junceum (Greene) D.R. Morgan & R.L. Hartm. -- accepted -- rush bristleweed
  Xanthisma spinulosum (Pursh) D.R. Morgan & R.L. Hartm. -- accepted -- cut-leaf ironplant, spiny goldenweed, lacy tansyaster
  Xanthisma spinulosum var. chihuahuanum (B.L. Turner & R.L. Hartm.) D.R. Morgan & R.L. Hartm. -- accepted
  Xanthisma spinulosum var. glaberrimum (Rydberg) D.R. Morgan & R.L. Hartm. -- accepted
  Xanthisma spinulosum var. gooddingii (A. Nelson) D.R. Morgan & R.L. Hartm. -- accepted
  Xanthisma spinulosum var. paradoxum (B.L. Turner & R.L. Hartm.) D.R. Morgan & R.L. Hartm. -- accepted
  Xanthisma spinulosum var. spinulosum (Pursh) D.R. Morgan & R.L. Hartm. -- accepted
  Xanthisma texanum DC. -- accepted -- Texas sleepydaisy, Texas sleepy-daisy
  Xanthisma texanum ssp. drummondii (Torr. & A. Gray) Semple -- not accepted -- Drummond's sleepydaisy
  Xanthisma texanum ssp. texanum DC. -- not accepted -- Texas sleepydaisy
  Xanthisma texanum ssp. texanum var. orientale Semple -- not accepted -- Texas sleepydaisy
  Xanthisma texanum ssp. texanum var. texanum DC. -- not accepted -- Texas sleepydaisy
  Xanthisma texanum var. drummondii (Torr. & A. Gray) A. Gray -- accepted -- Drummond's sleepydaisy
  Xanthisma texanum var. orientale Semple -- accepted -- Texas sleepydaisy
  Xanthisma texanum var. texanum DC. -- accepted -- Texas sleepydaisy
  Xanthisma viscidum (Woot. & Standl.) D.R. Morgan & R.L. Hartm. -- accepted -- sticky tansyaster
  Xanthium L. -- accepted -- cocklebur
  Xanthium acerosum Greene -- not accepted
  Xanthium ambrosioides Hook. & Arn. -- not accepted -- cocklebur
  Xanthium americanum Walter -- not accepted
  Xanthium californicum Greene -- not accepted
  Xanthium californicum var. rotundifolium Widder -- not accepted
  Xanthium calvum Millsp. & Sherff -- not accepted
  Xanthium campestre Greene -- not accepted
  Xanthium canadense Mill. -- not accepted
  Xanthium cavanillesii Schouw -- not accepted
  Xanthium cenchroides Millsp. & Sherff -- not accepted
  Xanthium chasei Fernald -- not accepted
  Xanthium chinense Mill. -- not accepted
  Xanthium commune Britton -- not accepted
  Xanthium curvescens Millsp. & Sherff -- not accepted
  Xanthium cylindraceum Millsp. & Sherff -- not accepted
  Xanthium echinatum Murray -- not accepted
  Xanthium echinellum Greene -- not accepted
  Xanthium glanduliferum Greene -- not accepted
  Xanthium globosum Shull -- not accepted
  Xanthium inflexum Mack. & Bush -- not accepted
  Xanthium italicum Moretti -- not accepted
  Xanthium macounii Britton -- not accepted
  Xanthium macrocarpum var. glabratum DC. -- not accepted
  Xanthium occidentale Bertol. -- not accepted
  Xanthium oligacanthum Piper -- not accepted
  Xanthium orientale L. -- not accepted
  Xanthium oviforme Wallr. -- not accepted
  Xanthium pensylvanicum Wallr. -- not accepted -- common cocklebur
  Xanthium saccharatum Wallr. -- not accepted
  Xanthium speciosum Kearney -- not accepted
  Xanthium spinosum L. -- accepted -- spiny cocklebur, Bathurst burr, cocklebur, spiny cockleburr
  Xanthium spinosum var. inerme Bel -- not accepted
  Xanthium strumarium L. -- accepted -- rough cocklebur, Canada cocklebur, cocklebur, common cocklebur, rough cockleburr, cockleburr
  Xanthium strumarium ssp. italicum (Moretti) D. Löve -- not accepted
  Xanthium strumarium var. canadense (Mill.) Torr. & A. Gray -- not accepted -- rough cocklebur, cocklebur, common cocklebur, Canada cockleburr, rough cockleburr, Canada cocklebur
  Xanthium strumarium var. glabratum (DC.) Cronquist -- not accepted -- cocklebur, common cocklebur, rough cocklebur, rough cockleburr
  Xanthium strumarium var. oviforme (Wallr.) M. Peck -- not accepted
  Xanthium strumarium var. pensylvanicum (Wallr.) M. Peck -- not accepted
  Xanthium strumarium var. strumarium L. -- not accepted -- common cocklebur, rough cocklebur, cocklebur, rough cockleburr
  Xanthium strumarium var. wootonii (Cockerell) W.C. Martin & C.R. Hutchins -- not accepted
  Xanthium varians Greene -- not accepted
  Xanthium wootonii Cockerell -- not accepted
  Xanthocephalum Willd. -- accepted -- xanthocephalum
  Xanthocephalum amoenum Shinners -- not accepted
  Xanthocephalum amoenum var. intermedium Shinners -- not accepted
  Xanthocephalum arizonicum (A. Gray) Shinners -- not accepted
  Xanthocephalum dracunculoides (DC.) Shinners -- not accepted
  Xanthocephalum glutinosum (Spreng.) Shinners -- not accepted
  Xanthocephalum gymnospermoides (A. Gray) Benth. & Hook. f. -- accepted -- San Pedro matchweed, matchweed
  Xanthocephalum lucidum Greene -- not accepted
  Xanthocephalum microcephalum (DC.) Shinners -- not accepted
  Xanthocephalum petradoria S.L. Welsh & Goodrich -- not accepted
  Xanthocephalum sarothrae (Pursh) Shinners -- not accepted
  Xanthocephalum sarothrae var. pomariense (S.L. Welsh) S.L. Welsh -- not accepted
  Xanthocephalum sphaerocephalum (A. Gray) Shinners -- not accepted
  Xanthocephalum sphaerocephalum var. eriocarpum (A. Gray) Shinners -- not accepted
  Xanthocephalum tenue (Greene) Shinners -- not accepted
  Xanthocephalum texanum (DC.) Shinners -- not accepted
  Xanthocephalum wrightii (A. Gray) A. Gray -- not accepted
  Xeranthemum bracteatum Vent. -- not accepted
  Xerochrysum Tzvelev -- accepted
  Xerochrysum bracteatum (Vent.) Tzvelev -- accepted -- bracted strawflower
  Ximenesia encelioides Cav. -- not accepted
  Ximenesia encelioides var. cana DC. -- not accepted
  Ximenesia encelioides var. exauriculata (B.L. Rob. & Greenm.) F.C. Gates -- not accepted
  Ximenesia encelioides var. nana A. Gray -- not accepted
  Ximenesia exauriculata (B.L. Rob. & Greenm.) Rydb. -- not accepted
  Ximenesia microptera DC. -- not accepted
  Ximenesia nana (A. Gray) Shinners -- not accepted
  Xylorhiza Nutt. -- accepted -- woodyaster, xylorhiza
  Xylorhiza cognata (H.M. Hall) T.J. Watson -- accepted -- Mecca woodyaster
  Xylorhiza coloradoensis (A. Gray) Rydb. -- not accepted
  Xylorhiza confertifolia (Cronquist) T.J. Watson -- accepted -- Henrieville woodyaster
  Xylorhiza cronquistii S.L. Welsh & N.D. Atwood -- accepted -- Cronquist's woodyaster
  Xylorhiza glabriuscula Nutt. -- accepted -- smooth woodyaster, woody aster, common woody aster
  Xylorhiza glabriuscula var. glabriuscula Nutt. -- not accepted -- smooth woodyaster
  Xylorhiza glabriuscula var. linearifolia T.J. Watson -- not accepted -- smooth woodyaster
  Xylorhiza glabriuscula var. villosa (Nutt.) A. Nelson -- not accepted -- villous woodyaster
  Xylorhiza lanceolata Rydb. -- not accepted
  Xylorhiza orcuttii (Vasey & Rose) Greene -- accepted -- Orcutt's aster
  Xylorhiza scopulorum A. Nelson -- not accepted
  Xylorhiza standleyi (Davidson) Davidson -- not accepted
  Xylorhiza tortifolia (Torr. & A. Gray) Greene -- accepted -- Mojave woodyaster, Mojave aster
  Xylorhiza tortifolia var. imberbis (Cronquist) T.J. Watson -- accepted -- imberis woodyaster
  Xylorhiza tortifolia var. tortifolia (Torr. & A. Gray) Greene -- accepted -- Mojave woodyaster, Mojave aster
  Xylorhiza venusta (M.E. Jones) A. Heller -- accepted -- charming woodyaster
  Xylorhiza villosa Nutt. -- not accepted
  Xylorhiza wrightii (A. Gray) Greene -- accepted -- Big Bend woodyaster
  Xylothamia G.L. Nesom, Suh, D. Morgan & Simpson -- not accepted -- desert goldenrod, xylothamia
  Xylothamia palmeri (A. Gray) G.L. Nesom -- not accepted -- Texas desert goldenrod, ericameria
  Xylothamia palmeri var. pachylepis (H.M. Hall) G.L. Nesom ex M. Lane & R.L. Hartm. -- not accepted
  Xylothamia triantha (S.F. Blake) G.L. Nesom -- not accepted -- Trans-Pecos desert goldenrod
  Yermo Dorn -- accepted -- desert yellowhead
  Yermo xanthocephalus Dorn -- accepted -- desert yellowhead
  Youngia Cass. -- accepted -- youngia
  Youngia japonica (L) DC -- accepted -- oriental false hawksbeard
  Youngia japonica ssp. elstonii (Hochr.) Stebbins -- not accepted
  Youngia japonica var. japonica (L) DC -- not accepted
  Youngia thunbergiana DC. -- not accepted
  Zaluzania Pers. -- accepted
  Zaluzania grayana B.L. Rob. & Greenm. -- accepted -- yellow streamers
  Zexmenia brevifolia A. Gray -- not accepted
  Zexmenia hispida auct. non (Kunth) A. Gray ex Small -- not accepted
  Zexmenia podocephala (A. Gray) A. Gray -- not accepted
  Zinnia L. -- accepted -- zinnia
  Zinnia acerosa (DC.) A. Gray -- accepted -- desert zinnia, spinyleaf zinnia
  Zinnia angustifolia Kunth -- accepted -- narrowleaf zinnia
  Zinnia anomala A. Gray -- accepted -- shortray zinnia
  Zinnia elegans Jacq. -- not accepted
  Zinnia grandiflora Nutt. -- accepted -- Rocky Mountain zinnia, plains zinnia, Texas zinnia
  Zinnia maritima Kunth -- accepted -- Palmer's zinnia
  Zinnia maritima var. palmeri (A. Gray) B.L. Turner -- not accepted -- Palmer's zinnia
  Zinnia multiflora L. -- not accepted
  Zinnia palmeri A. Gray -- accepted -- Palmer's zinnia
  Zinnia pauciflora L. -- not accepted
  Zinnia peruviana (L.) L. -- accepted -- Peruvian zinnia
  Zinnia pumila A. Gray -- not accepted
  Zinnia violacea Cav. -- accepted -- elegant zinnia
  Zollikoferia elquiensis Phil. -- not accepted
   

A gray bar