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 Lam. -- not accepted -- longleaf aster
  Aster longifolius sensu Semple & Heard non Lam. -- not accepted
  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 (Walter) Britton non Nutt. -- not accepted -- soft goldenaster
  Chrysopsis pilosa Nutt. -- not accepted -- soft goldenaster, soft goldaster
  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) Green