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Composite List of Weeds
The WSSA composite list of weeds includes 3756 plants (2847 unique species and 909 synonymic names) compiled by the Standardized Plant Names subcommittee. Download the WSSA Composite List of Weeds 2023 Update (Excel file)
Please note
Not all plants included on the list are weedy in all environments and common crop plants and tree species are also included in the list.
SEARCH WEEDS
| Common Name | Latin Name | Bayer Code | US Code | family |
|---|---|---|---|---|
| black acacia | Acacia melanoxylon R. Br. | ACAME | ACME | Fabaceae |
| blackbrush acacia | Vachellia rigidula (Benth.) Seigler & Ebinger | ACARI | VARI | Fabaceae |
| catclaw acacia | Senegalia greggii (A. Gray) Britton & Rose | ACAGR | SEGR4 | Fabaceae |
| everblooming acacia | Acacia retinodes Schltdl. | ACART | ACRE2 | Fabaceae |
| mescat acacia | Vachellia constricta (Benth.) Seigler & Ebinger | ACACS | ACCO2 | Fabaceae |
| sweet acacia | Vachellia farnesiana (L.) Wight & Arn. | ACAFA | VAFA | Fabaceae |
| twisted acacia | Vachellia tortuosa (L.) Seigler & Ebinger | ACATT | VATO2 | Fabaceae |
| acuate | Lagascea mollis Cav. | LAGMO | LAMO5 | Asteraceae |
| pheasanteye adonis | Adonis annua L. | ADOAN | ADAN | Ranunculaceae |
| spring adonis | Adonis vernalis L. | ADOVE | ADVE | Ranunculaceae |
| tropic ageratum | Ageratum conyzoides L. | AGECO | AGCO | Asteraceae |
| common agrimony | Agrimonia gryposepala Wallr. | AGIGR | AGGR2 | Rosaceae |
| roadside agrimony | Agrimonia striata Michx. | AGIST | AGST | Rosaceae |
| air-potato | Dioscorea bulbifera L. | DIUBU | DIBU | Dioscoreaceae |
| albizia | Albizia procera (Roxb.) Benth. | ALBPR | ALPR | Fabaceae |
| European alder | Alnus glutinosa (L.) Gaertn. | ALUGL | ALGL2 | Betulaceae |
| red alder | Alnus rubra Bong. | ALURB | ALRU2 | Betulaceae |
| speckled alder | Alnus incana (L.) Moench ssp. rugosa (Du Roi) R. T. Clausen | ALURG | ALINR | Betulaceae |
| alexandergrass | Urochloa plantaginea (Link) R.D. Webster | BRAPL | URPL | Poaceae |
| smallflowered alexandergrass | Urochloa subquadripara (Trin.) R.D. Webster | BRASU | URSU2 | Poaceae |
| alfalfa | Medicago sativa L. | MEDSA | MESA | Fabaceae |
| alfombrilla | Drymaria arenarioides Humb. & Bonpl. ex Schult. | DRYAR | DRAR7 | Caryophyllaceae |
| European alkaligrass | Puccinellia distans (Jacq.) Parl. | PUCDI | PUDI | Poaceae |
| alkalisink goldfields | Lasthenia chrysantha (Greene ex A. Gray) Greene | LTECH | LACH2 | Asteraceae |
| alkaliweed | Cressa truxillensis Kunth | CSVTR | CRTR5 | Convolvulaceae |
| bent alligator-flag | Thalia geniculata L. | THAGE | THGE2 | Marantaceae |
| alligatorweed | Alternanthera philoxeroides (Mart.) Griseb. | ALRPH | ALPH | Amaranthaceae |
| alyceclover | Alysicarpus vaginalis (L.) DC. | ALZVA | ALVA2 | Fabaceae |
| alyssum | Alyssum simplex Rudolphi | ALSI8 | Brassicaceae | |
| dwarf alyssum | Alyssum desertorum Stapf | AYSDE | ALDE | Brassicaceae |
| hoary alyssum | Berteroa incana (L.) DC. | BEFIN | BEIN2 | Brassicaceae |
| sweet alyssum | Lobularia maritima (L.) Desv. | LOUMA | LOMA | Brassicaceae |
| yellow alyssum | Alyssum alyssoides (L.) L. | AYSAL | ALAL3 | Brassicaceae |
| giant amaranth | Amaranthus australis (A. Gray) Sauer | AMAAU | AMAU | Amaranthaceae |
| livid amaranth | Amaranthus blitum L. | AMALI | AMBL2 | Amaranthaceae |
| low amaranth | Amaranthus deflexus L. | AMADE | AMDE | Amaranthaceae |
| Palmer amaranth | Amaranthus palmeri S. Watson | AMAPA | AMPA | Amaranthaceae |
| Powell amaranth | Amaranthus powellii S. Watson | AMAPO | AMPO2 | Amaranthaceae |
| sandhills amaranth | Amaranthus arenicola I.M. Johnst. | AMAAR | AMAR | Amaranthaceae |
| slender amaranth | Amaranthus viridis L. | AMAVI | AMVI | Amaranthaceae |
| spiny amaranth | Amaranthus spinosus L. | AMASP | AMSP | Amaranthaceae |
| spleen amaranth | Amaranthus dubius Mart. ex Thell. | AMADU | AMDU | Amaranthaceae |
| Torrey amaranth | Amaranthus torreyi (A. Gray) Benth. ex S. Watson | AMATO | AMTO6 | Amaranthaceae |
| ambulia | Limnophila indica (L.) Druce | LIOIN | LIIN5 | Plantaginaceae |
| pink ammannia | Ammannia latifolia L. | AMMLA | AMLA3 | Lythraceae |
| purple ammannia | Ammannia robusta Heer & Regel | AMMRB | AMRO3 | Lythraceae |
| greater ammi | Ammi majus L. | AMIMA | AMMA | Apiaceae |
| toothpick ammi | Ammi visnaga (L.) Lam. | AMIVI | AMVI2 | Apiaceae |
| northern androsace | Androsace septentrionalis L. | ANSSE | ANSE4 | Primulaceae |
| purplestem angelica | Angelica atropurpurea L. | ANKAT | ANAT | Apiaceae |
| woodland angelica | Angelica sylvestris L. | ANKSY | ANSY2 | Apiaceae |
| spurred anoda | Anoda cristata (L.) Schltdl. | ANVCR | ANCR2 | Malvaceae |
| green antelopehorn | Asclepia viridis Walter | ASVI2 | Apocynaceae | |
| apple of Peru | Nicandra physalodes (L.) Gaertn. | NICPH | NIPH | Solanaceae |
| yellow archangel | Lamiastrum galeobdolon (L.) Ehrend. & Polatschek | LSTGA | LAGA2 | Lamiaceae |
| shoebutton ardisia | Ardisia elliptica Thunb. | ADAEL | AREL4 | Myrsinaceae |
| green arrow arum | Peltandra virginica (L.) Schott | PETVI | PEVI | Araceae |
| marsh arrowgrass | Triglochin palustris L. | TRLPA | TRPA28 | Juncaginaceae |
| seaside arrowgrass | Triglochin maritima L. | TRLMA | TRMA20 | Juncaginaceae |
| arrowhead | Sagittaria sagittifolia L. | SAGSA | SASA7 | Alismataceae |
| awl leaf arrowhead | Sagittaria subulata (L.) Buchenau | SAGSU | SASU | Alismataceae |
| California arrowhead | Sagittaria montevidensis Cham. & Schltdl. | SAGMO | SAMO | Alismataceae |
| common arrowhead | Sagittaria latifolia Willd. | SAGLT | SALA2 | Alismataceae |
| delta arrowhead | Sagittaria platyphylla (Engelm.) J.G. Sm. | SAGPL | SAPL | Alismataceae |
| grassy arrowhead | Sagittaria graminea Michx. | SAGGR | SAGR | Alismataceae |
| Gregg arrowhead | Sagittaria longiloba Engelm. ex J.G. Sm. | SAGLO | SALO2 | Alismataceae |
| lanceleaf arrowhead | Sagittaria lancifolia L. | SAGFA | SALA | Alismataceae |
| quillwort arrowhead | Sagittaria isoetiformis J.G. Sm. | SAGIS | SAIS | Alismataceae |
| wedgeleaf arrowhead | Sagittaria cuneata Sheldon | SAGCU | SACU | Alismataceae |
| jointhead arthraxon | Arthraxon hispidus (Thunb.) Makino | ARAHI | ARHI3 | Poaceae |
| Jerusalem artichoke | Helianthus tuberosus L. | HELTU | HETU | Asteraceae |
| artillery weed | Pilea microphylla (L.) Liebm. | PILMI | PIMI2 | Urticaceae |
| Italian arum | Arum italicum Mill. | ABGIT | ARIT | Araceae |
| shamel ash | Fraxinus uhdei (Wenzig) Lingelsh. | FRXUH | FRUH | Oleaceae |
| green ash | Fraxinus pennsylvanica Marshall | FRXPE | FRPE | Oleaceae |
| white ash | Fraxinus americana L. | FRXAM | FRAM2 | Oleaceae |
| asparagus | Asparagus officinalis L. | ASPOF | ASOF | Asparagaceae |
| quaking aspen | Populus tremuloides Michx. | POPTM | POTR5 | Salicaceae |
| bushy aster | Symphyotrichum dumosum (L.) G. L. Nesom | ASTDU | SYDU2 | Asteraceae |
| bushy aster | Symphyotrichum lateriflorum (L.) Á. Löve & D. Löve | ASTLF | SYLA4 | Asteraceae |
| heath aster | Symphyotrichum ericoides (L.) G. L. Nesom | ASTER | SYER | Asteraceae |
| New England aster | Symphyotrichum novae-angliae (L.) G. L. Nesom | ASTNA | SYNO2 | Asteraceae |
| savoryleaf aster | Ionactis linariifolius (L.) Greene | ASTLI | IOLI2 | Asteraceae |
| slender aster | Symphyotrichum divaricatum (Nutt.) Nesom | ZMYDI | SYDI2 | Asteraceae |
| spiny aster | Chloracantha spinosa (Benth.) G. L. Nesom | ASTSN | CHSP11 | Asteraceae |
| western mountain aster | Symphyotrichum spathulatum (Lindl.) G. L. Nesom | ZMYSP | SYSP | Asteraceae |
| white heath aster | Symphyotrichum pilosum (Willd.) G. L. Nesom | ASTPI | SYPI2 | Asteraceae |
| white panicle aster | Symphyotrichum lanceolatum (Willd.) G. L. Nesom | ASTLN | SYLA6 | Asteraceae |
| white prairie aster | Symphyotrichum falcatum (Lindl.) G. L. Nesom | ZMYFA | SYFA | Asteraceae |
| beach sheoak | Casuarina equisetifolia L. | CSUEQ | CAEQ | Casuarinaceae |
| autumn olive | Elaeagnus umbellata Thunb. | ELGUM | ELUM | Elaeagnaceae |
| white avens | Geum canadense Jacq. | GEUCA | GECA7 | Rosaceae |
| yellow avens | Geum aleppicum Jacq. | GEUAL | GEAL3 | Rosaceae |
| baby blue eyes | Nemophila menziesii Hook. & Arn. | NMPME | NEME | Hydrophyllaceae |
| smallflower baby blue eyes | Nemophila aphylla (L.) Brummitt | NEAP | Hydrophyllaceae | |
| babysbreath | Gypsophila paniculata L. | GYPPA | GYPA | Caryophyllaceae |
| eastern baccharis | Baccharis halimifolia L. | BACHA | BAHA | Asteraceae |
| willow baccharis | Baccharis glutinosa Pers. | BACGL | BAGL2 | Asteraceae |
| bagpod | Sesbania vesicaria (Jacq.) Elliott | SEBVE | SEVE | Fabaceae |
| bahiagrass | Paspalum notatum Flueggé | PASNO | PANO2 | Poaceae |
| Pensacola bahiagrass | Paspalum notatum Flueggé var. saurae Parodi | PASNS | PANOS | Poaceae |
| balloonvine | Cardiospermum halicacabum L. | CRIHA | CAHA13 | Sapindaceae |
| lemon balm | Melissa officinalis L. | MLSOF | MEOF2 | Lamiaceae |
| balm of Gilead | Populus x jackii Sarg. [balsamifera x deltoides] | POPBS | POJA2 | Salicaceae |
| garden balsam | Impatiens balsamina L. | IPABA | IMBA | Balsaminaceae |
| balsam apple | Momordica charantia L. | MOMCH | MOCH2 | Cucurbitaceae |
| golden bamboo | Phyllostachys aurea Carrière ex A. Rivière & C. Rivière | PLLAR | PHAU8 | Poaceae |
| bamboovine | Smilax laurifolia L. | SMILA | SMLA | Smilacaceae |
| wild bamboovine | Smilax auriculata Walter | SMIAU | SMAU | Smilacaceae |
| red baneberry | Actaea rubra (Ait.) Willd. | AATSR | ACRU2 | Ranunculaceae |
| Beale barberry | Berberis bealei Fortune | MAHBE | Berberidaceae | |
| European barberry | Berberis vulgaris L. | BEBVU | BEVU | Berberidaceae |
| Japanese barberry | Berberis thunbergii DC. | BEBTH | BETH | Berberidaceae |
| barbgrass | Hainardia cylindrica (Willd.) Greuter | MNRCY | HACY | Poaceae |
| barbwire grass | Cymbopogon refractus (R. Br.) A. Camus | CYGRE | CYRE | Poaceae |
| barley | Hordeum vulgare L. | HORVX | HOVU | Poaceae |
| Arizona barley | Hordeum arizonicum Covas | HORAR | HOAR | Poaceae |
| foxtail barley | Hordeum jubatum L. | HORJU | HOJU | Poaceae |
| hare barley | Hordeum murinum L. ssp. leporinum (Link) Arcang. | HORLE | HOMUL | Poaceae |
| little barley | Hordeum pusillum Nutt. | HORPU | HOPU | Poaceae |
| meadow barley | Hordeum brachyantherum Nevski | HORBR | HOBR2 | Poaceae |
| Mediterranean barley | Hordeum marinum Huds. ssp. gussoneanum (Parl.) Thell. | HORMG | HOMAG | Poaceae |
| mouse barley | Hordeum murinum L. | HORMU | HOMU | Poaceae |
| smooth barley | Hordeum murinum L. ssp. glaucum (Steud.) Tzvelev | HORMC | HOMUG | Poaceae |
| spontaneous barley | Hordeum vulgare L. ssp. spontaneum (K. Koch) Thell. | HORSP | HOSP | Poaceae |
| wall barley | Hordeum murinum L. ssp. murinum | HORMU | HOMUM | Poaceae |
| barnyardgrass | Echinochloa crus-galli (L.) P. Beauv. | ECHCG | ECCR | Poaceae |
| rough barnyardgrass | Echinochloa muricata (P. Beauv.) Fernald | ECHPU | ECMU2 | Poaceae |
| western barnyardgrass | Echinochloa muricata (P. Beauv.) Fernald var. microstachya Wiegand | ECHCM | ECMUM | Poaceae |
| common bartsia | Odontites vulgaris Moench | ODOVU | ODVU | Scrophulariaceae |
| red bartsia | Odontites vernus (Bellardi) Dumort. ssp. serotinus (Dumort.) Corb. | ODVES | Scrophulariaceae | |
| wild basil | Clinopodium vulgare L. | STIVU | CLVU | Lamiaceae |
| basketgrass | Oplismenus hirtellus (L.) P. Beauv. | OPLHI | OPHI | Poaceae |
| fivehook bassia | Bassia hyssopifolia (Pall.) Kuntze | BAFHY | BAHY | Chenopodiaceae |
| bayberry | Morella pensylvanica (Mirb.) Kartesz | MYRPE | MOPE6 | Myricaceae |
| European beachgrass | Ammophila arenaria (L.) Link | AMOAR | AMAR4 | Poaceae |
| horned beakrush | Rhynchospora corniculata (Lam.) A. Gray | RHCCN | RHCO2 | Cyperaceae |
| pinehill beakrush | Rhynchospora globularis (Chapm.) Small | RHCGL | RHGL2 | Cyperaceae |
| precatory bean | Abrus precatorius L. | ABRPR | ABPR3 | Fabaceae |
| Syrian beancaper | Zygophyllum fabago L. | ZYGFA | ZYFA | Zygophyllaceae |
| bearberry | Arctostaphylos uva-ursi (L.) Spreng. | ARYUU | ARUV | Ericaceae |
| cane beardgrass | Bothriochloa barbinodis (Lag.) Herter | ANOBA | BOBA3 | Poaceae |
| pitted beardgrass | Bothriochloa pertusa (L.) A. Camus | ANOPE | BOPE2 | Poaceae |
| silver beardgrass | Bothriochloa saccharoides (Sw.) Rydb. | ANOSA | BOSA | Poaceae |
| prostrate ceanothus | Ceanothus prostratus Benth. | CEAPR | CEPR | Rhamnaceae |
| American beautyberry | Callicarpa americana L. | CLIAM | CAAM2 | Verbenaceae |
| catchweed bedstraw | Galium aparine L. | GALAP | GAAP2 | Rubiaceae |
| heath bedstraw | Galium saxatile L. | GALHA | GASA2 | Rubiaceae |
| Lamarck bedstraw | Galium divaricatum Pourr. ex Lam. | GALDI | GADI | Rubiaceae |
| northern bedstraw | Galium boreale L. | GALBO | GABO2 | Rubiaceae |
| rough bedstraw | Galium asprellum Michx. | GALAS | GAAS2 | Rubiaceae |
| smooth bedstraw | Cruciata laevipes Opiz. | CCTLA | CRLA13 | Rubiaceae |
| smooth bedstraw | Galium mollugo L. | GALMO | GAMO | Rubiaceae |
| threehorn bedstraw | Galium tricornutum Dandy | GALTC | GATR6 | Rubiaceae |
| tiny bedstraw | Galium murale (L.) All. | GALMU | GAMU4 | Rubiaceae |
| wall bedstraw | Galium parisiense L. | GALPR | GAPA5 | Rubiaceae |
| yellow bedstraw | Galium verum L. | GALVE | GAVE | Rubiaceae |
| lemon beebalm | Monarda citriodora Cerv. ex Lag. | MOACI | MOCI | Lamiaceae |
| pony beebalm | Monarda pectinata Nutt. | MOAPE | MOPE | Lamiaceae |
| spotted beebalm | Monarda punctata L. | MOAPU | MOPU | Lamiaceae |
| longflower beeblossom | Oenothera filiformis (Small) W. L. Wagner & Hoch | GAALO | OEFI2 | Onagraceae |
| river sheoak | Casuarina cunninghamiana Miq. | CSUCU | CACU8 | Casuarinaceae |
| gray sheoak | Casuarina glauca Sieber ex Spreng. | CSUGL | CAGL11 | Casuarinaceae |
| Rocky Mountain beeplant | Cleome serrulata Pursh | CLESE | CLSE | Cleomaceae |
| yellow beeplant | Cleome lutea Hook. | CLELU | CLLU2 | Cleomaceae |
| beggarslice | Hackelia virginiana (L.) I. M. Johnst. | HACVI | HAVI2 | Boraginaceae |
| bearded beggarticks | Bidens aristosa (Michx.) Britton | BIDAR | BIAR | Asteraceae |
| Bigelow beggarticks | Bidens bigelovii A. Gray | BIDBG | BIBI | Asteraceae |
| bur beggarticks | Bidens tripartita L. | BIDTR | BITR | Asteraceae |
| crown beggarticks | Bidens trichosperma (Michx.) Britton | BIDCO | BITR2 | Asteraceae |
| devils beggarticks | Bidens frondosa L. | BIDFR | BIFR | Asteraceae |
| hairy beggarticks | Bidens pilosa L. | BIDPI | BIPI | Asteraceae |
| marsh beggarticks | Bidens mitis (Michx.) Sherff | BIDMI | BIMI | Asteraceae |
| nodding beggarticks | Bidens cernua L. | BIDCE | BICE | Asteraceae |
| tall beggarticks | Bidens vulgata Greene | BIDVU | BIVU | Asteraceae |
| creeping beggarweed | Desmodium incanum DC. | DEDCA | DEIN3 | Fabaceae |
| Florida beggarweed | Desmodium tortuosum (Sw.) DC. | DEDTO | DETO | Fabaceae |
| threeflower beggarweed | Desmodium triflorum (L.) DC. | DEDTR | DETR4 | Fabaceae |
| bellardia | Bellardia trixago (L.) All. | BEQTR | BETR | Orobanchaceae |
| American bellflower | Campanula americana L. | CMPAM | CAAM6 | Campanulaceae |
| Asiatic bellflower | Wahlenbergia marginata (Thunb.) A. DC. | WAHMA | WAMA | Campanulaceae |
| clustered bellflower | Campanula glomerata L. | CMPGL | CAGL2 | Campanulaceae |
| creeping bellflower | Campanula rapunculoides L. | CMPRA | CARA | Campanulaceae |
| little bellwort | Uvularia sessilifolia L. | UVLSE | UVSE | Colchicaceae |
| autumn bentgrass | Agrostis perennans (Walter) Tuck. | AGSPE | AGPE | Poaceae |
| colonial bentgrass | Agrostis capillaris L. | AGSTE | AGCA5 | Poaceae |
| creeping bentgrass | Agrostis stolonifera L. | AGSST | AGST2 | Poaceae |
| Pacific bentgrass | Agrostis avenacea J. F. Gmel. | AGSAV | AGAV | Poaceae |
| rough bentgrass | Agrostis scabra Willd. | AGSSC | AGSC5 | Poaceae |
| velvet bentgrass | Agrostis canina L. | AGSCA | AGCA4 | Poaceae |
| winter bentgrass | Agrostis hyemalis (Walter) Britton, Sterns & Poggenb. | AGSHI | AGHY | Poaceae |
| wild bergamot | Monarda fistulosa L. | MOAFI | MOFI | Lamiaceae |
| bermudagrass | Cynodon dactylon (L.) Pers. | CYNDA | CYDA | Poaceae |
| African bermudagrass | Cynodon transvaalensis Burtt Davy | CYNTR | CYTR | Poaceae |
| hybrid bermudagrass | Cynodon dactylon hybrids | CYNDH | Poaceae | |
| hybrid bermudagrass | Cynodon transvaalensis Burtt Davy x dactylon (L.) Pers. | Poaceae | ||
| Himalayan berry | Rubus bifrons Vest ex Tratt. | RUBBF | RUBI | Rosaceae |
| fieldnettle betony | Stachys arvensis (L.) L. | STAAR | STAR | Lamiaceae |
| Florida betony | Stachys floridana Shuttlw. ex Benth. | STAFL | STFL4 | Lamiaceae |
| hedgenettle betony | Stachys annua (L.) L. | STAAN | STAN | Lamiaceae |
| biddy biddy | Acaena novae-zelandiae Kirk | ACENZ | ACNO7 | Rosaceae |
| pale biddy biddy | Acaena pallida (Kirk) Allan | ACEPA | ACPA14 | Rosaceae |
| field bindweed | Convolvulus arvensis L. | CONAR | COAR4 | Convolvulaceae |
| hairy bindweed | Calystegia pubescens Lindl. | CAGPU | CAPU17 | Convolvulaceae |
| hedge bindweed | Calystegia sepium (L.) R. Br. | CAGSE | CASE13 | Convolvulaceae |
| hollyhock bindweed | Convolvulus althaeoides L. | CONAL | COAL4 | Convolvulaceae |
| Texas bindweed | Convolvulus equitans Benth. | CONEQ | COEQ | Convolvulaceae |
| gray birch | Betula populifolia Marshall | BETPO | BEPO | Betulaceae |
| river birch | Betula nigra L. | BETNI | BENI | Betulaceae |
| biscuitroot | Lomatium bicolor (S. Watson) J. M. Coult. & Rose | LOMLE | LOBI | Apiaceae |
| mock bishopsweed | Ptilimnium capillaceum (Michx.) Raf. | PMMCA | PTCA | Apiaceae |
| bittercherry | Prunus emarginata (Douglas) Eaton | PRNEM | PREM | Rosaceae |
| cuckoo bittercress | Cardamine pratensis L. | CARPR | CAPR3 | Brassicaceae |
| flexuous bittercress | Cardamine flexuosa With. | CARFL | CAFL14 | Brassicaceae |
| hairy bittercress | Cardamine hirsuta L. | CARHI | CAHI3 | Brassicaceae |
| little bittercress | Cardamine oligosperma Nutt. | CAROL | CAOL | Brassicaceae |
| narrowleaf bittercress | Cardamine impatiens L. | CARIM | CAIM | Brassicaceae |
| Pennsylvania bittercress | Cardamine pensylvanica Muhl. ex. Willd. | CARPE | CAPE3 | Brassicaceae |
| smallflowered bittercress | Cardamine parviflora L. | CARPA | CAPA12 | Brassicaceae |
| American bittersweet | Celastrus scandens L. | CELSC | CESC | Celastraceae |
| roundleaf bittersweet | Celastrus orbiculatus Thunb. | CELOR | CEOR7 | Celastraceae |
| Allegheny blackberry | Rubus allegheniensis Porter | RUBAL | RUAL | Rosaceae |
| cutleaf blackberry | Rubus laciniatus Willd. | RUBLA | RULA | Rosaceae |
| European blackberry | Rubus fruticosus L. | RUBFR | RUFR80 | Rosaceae |
| European blackberry | Rubus vestitus Weihe & Nees | RUBVS | RUVE | Rosaceae |
| highbush blackberry | Rubus argutus Link | RUBAG | RUAR2 | Rosaceae |
| Himalaya blackberry | Rubus armeniacus Focke | RUBAE | RUAR9 | Rosaceae |
| Pacific blackberry | Rubus ursinus Cham. & Schldl. | RUBUR | RUUR | Rosaceae |
| Pennsylvania blackberry | Rubus pensilvanicus Poir. | RUBPS | RUPE3 | Rosaceae |
| sand blackberry | Rubus cuneifolius Pursh | RUBCU | RUCU | Rosaceae |
| yellow Himalaya blackberry | Rubus ellipticus Sm. | RUBEL | RUEL3 | Rosaceae |
| blackeyed Susan | Rudbeckia hirta L. var. pulcherrima Farw. | RUDHP | RUHIP | Asteraceae |
| blackgrass | Alopecurus myosuroides Huds. | ALOMY | ALMY | Poaceae |
| blackgum | Nyssa sylvatica Marshall | NYSSY | NYSY | Cornaceae |
| bladderflower | Araujia sericifera Brot. | AJASE | ARSE8 | Asclepiadaceae |
| Gordon bladderpod | Physaria gordonii (A. Gray) O'Kane & Al-Shehbaz | LEUGO | Brassicaceae | |
| common bladderwort | Utricularia vulgaris L. | UTRVU | UTVU | Lentibulariaceae |
| floating bladderwort | Utricularia inflata Walter | UTRIN | UTIN | Lentibulariaceae |
| Florida bladderwort | Utricularia floridana Nash | UTRFL | UTFL | Lentibulariaceae |
| humped bladderwort | Utricularia gibba L. | UTRBI | UTGI | Lentibulariaceae |
| leafy bladderwort | Utricularia foliosa L. | UTRFO | UTFO | Lentibulariaceae |
| minute bladderwort | Utricularia olivacea C. Wright ex Griseb. | UTROL | UTOL | Lentibulariaceae |
| purple bladderwort | Utricularia purpurea Walter | UTRPU | UTPU | Lentibulariaceae |
| swollen bladderwort | Utricularia radiata Small | UTRRA | UTRA | Lentibulariaceae |
| bractless blazingstar | Mentzelia nuda (Pursh) Torr. & A. Gray | MNZMU | MENU | Loasaceae |
| cusp blazingstar | Liatris punctata Hook. var. mucronata (DC.) B. L. Turner | LIPUM2 | Asteraceae | |
| smoothstem blazingstar | Mentzelia laevicaulis (Hook.) Torr. & A. Gray | MNZLA | MELA2 | Loasaceae |
| bloodberry | Rivina humilis L. | RIVHU | RIHU2 | Phytolaccaceae |
| Tasmanian blue gum | Eucalyptus globulus Labill. | EUCGL | EUGL | Myrtaceae |
| bluebead lily | Clintonia borealis (Ait.) Raf. | CJXBO | CLBO3 | Liliaceae |
| northern bluebells | Mertensia paniculata (Aiton) G. Don | MTSPA | MEPA | Boraginaceae |
| alpine blueberry | Vaccinium uliginosum L. | VACUL | VAUL | Ericaceae |
| low blueberry | Vaccinium pallidum Aiton | VACPL | VAPA4 | Ericaceae |
| blueblossom | Ceanothus thrysiflorus Eschsch. | CEATH | CETH | Rhamnaceae |
| bluebuttons | Knautia arvensis (L.) Coult. | KNAAR | KNAR | Caprifoliaceae |
| bluedicks | Dichelostemma capitatum (Benth.) Alph. Wood | DKLCA | DICA14 | Asparagaceae |
| Montana blue eyed grass | Sisyrinchium montanum Greene | SISMO | SIMO2 | Iridaceae |
| narrowleaf blue eyed grass | Sisyrinchium angustifolium Mill. | SISAN | SIAN3 | Iridaceae |
| annual bluegrass | Poa annua L. | POAAN | POAN | Poaceae |
| bulbous bluegrass | Poa bulbosa L. | POABU | POBU | Poaceae |
| Canada bluegrass | Poa compressa L. | POACO | POCO | Poaceae |
| Kentucky bluegrass | Poa pratensis L. | POAPR | POPR | Poaceae |
| roughstalk bluegrass | Poa trivialis L. | POATR | POTR2 | Poaceae |
| wood bluegrass | Poa nemoralis L. | POANE | PONE | Poaceae |
| Angleton bluestem | Dichanthium aristatum (Poir.) C. E. Hubbard | DIHAR | DIAR5 | Poaceae |
| big bluestem | Andropogon gerardi Vitman | ANOGE | ANGE | Poaceae |
| bushy bluestem | Andropogon glomeratus (Walter) Britton, Sterns & Poggenb. | ANOGL | ANGL2 | Poaceae |
| little bluestem | Schizachyrium scoparium (Michx.) Nash | ANOSC | SCSC | Poaceae |
| plains bluestem | Bothriochloa ischaemum (L.) Keng var. ischaemum | DIHIS | BOIS | Poaceae |
| silky bluestem | Dichanthium sericeum (R. Br.) A. Camus | DIHSE | DISE5 | Poaceae |
| splitbeard bluestem | Andropogon ternarius Michx. | ANOTE | ANTE2 | Poaceae |
| yellow bluestem | Bothriochloa ischaemum (L.) Keng var. songarica (Rupr. ex Fisch. & C. A. Mey.) Celarier & J. R. Harlan | BOTIS | BOISS | Poaceae |
| roundleaf bluet | Houstonia procumbens (Walter ex J. F. Gmel.) Standl. | HYOPR | HOPR | Rubiaceae |
| bluets | Houstonia caerulea L. | HOUCA | HOCA4 | Rubiaceae |
| blueweed | Echium vulgare L. | EHIVU | ECVU | Boraginaceae |
| Texas blueweed | Helianthus ciliaris DC. | HELCI | HECI | Asteraceae |
| bogmat | Wolffiella gladiata (Hegelm.) Hegelm. | WOFGL | WOGL2 | Araceae |
| bogmoss | Mayaca fluviatilis Aubl. | MJYFL | MAFL2 | Mayacaceae |
| boneset | Eupatorium perfoliatum L. | EUPPE | EUPE3 | Asteraceae |
| false boneset | Brickellia eupatorioides (L.) Shinners | KUHEU | BREU | Asteraceae |
| hyssopleaved boneset | Eupatorium hyssopifolium L. | EUPHY | EUHY | Asteraceae |
| late boneset | Eupatorium serotinum Michx. | EUPSE | EUSE2 | Asteraceae |
| common borage | Borago officinalis L. | BOROF | BOOF | Boraginaceae |
| bouncingbet | Saponaria officinalis L. | SAWOF | SAOF4 | Caryophyllaceae |
| hoary bowlesia | Bowlesia incana Ruiz & Pav. | BOWIN | BOIN3 | Apiaceae |
| victorian box | Pittosporum undulatum Vent. | PTUUN | PIUN2 | Pittosporaceae |
| boxelder | Acer negundo L. | ACRNE | ACNE2 | Sapindaceae |
| African boxthorn | Lycium ferocissimum Miers | LYUFE | LYFE4 | Solanaceae |
| brackenfern | Pteridium aquilinum (L.) Kuhn | PTEAQ | PTAQ | Dennstaedtiaceae |
| eastern brackenfern | Pteridium aquilinum (L.) Kuhn var. latiusculum (Desv.) Underw. ex A. Heller | PTEAL | PTAQL | Dennstaedtiaceae |
| western brackenfern | Pteridium aquilinum (L.) Kuhn var. pubescens Underw. | PTEAP | PTAQP2 | Dennstaedtiaceae |
| bractscale | Atriplex serenana A. Nelson | ATXSR | ATSE2 | Chenopodiaceae |
| brasil | Condalia hookeri M.C. Johnst. | CNCHO | COHO | Rhamnaceae |
| brassbuttons | Cotula coronopifolia L. | CULCO | COCO7 | Asteraceae |
| Mexican brassbuttons | Cotula mexicana (DC.) Cabrera | CULME | COME15 | Asteraceae |
| southern brassbuttons | Cotula australis (Sieber ex Spreng.) Hook. f. | CULAU | COAU3 | Asteraceae |
| African bristlegrass | Setaria sphacelata (Schumach.) Stapf & C. E. Hubb. | SETSP | SESP5 | Poaceae |
| giant bristlegrass | Setaria magna Griseb. | SETMG | SEMA6 | Poaceae |
| bristly sarsaparilla | Aralia hispida Vent. | ARLHI | ARHI2 | Araliaceae |
| Arizona brome | Bromus arizonicus (Shear) Stebbins | BROAZ | BRAR4 | Poaceae |
| bald brome | Bromus racemosus L. | BRORA | BRRA2 | Poaceae |
| California brome | Bromus carinatus Hook. & Arn. | BROCN | BRCA5 | Poaceae |
| cheatgrass | Bromus tectorum L. | BROTE | BRTE | Poaceae |
| field brome | Bromus arvensis L. | BROAV | BRAR5 | Poaceae |
| foxtail brome | Bromus madritensis L. | BROMA | BRMA3 | Poaceae |
| Japanese brome | Bromus japonicus Houtt. | BROJA | BRJA | Poaceae |
| meadow brome | Bromus erectus Huds. | BROER | BRER3 | Poaceae |
| poverty brome | Bromus sterilis L. | BROST | BRST2 | Poaceae |
| rattlesnake brome | Bromus briziformis Fisch. & C. A. Mey. | BROBR | BRBR5 | Poaceae |
| red brome | Bromus rubens L. | BRORU | BRRU2 | Poaceae |
| ripgut brome | Bromus diandrus Roth | BRODI | BRDIR2 | Poaceae |
| smooth brome | Bromus inermis Leyss. | BROIN | BRIN2 | Poaceae |
| soft brome | Bromus hordeaceus L. | BROMO | BRHO2 | Poaceae |
| weedy brome | Bromus alopecuros Poir. | BROAL | BRAL2 | Poaceae |
| bridal broom | Retama monosperma L. | LGOMO | REMO2 | Fabaceae |
| Canary Island broom | Genista canariensis L. | CZSCA | GECA16 | Fabaceae |
| French broom | Genista monspessulana (L.) L. A. S. Johnson | TLNMO | GEMO2 | Fabaceae |
| Portuguese broom | Cytisus striatus (Hill) Rothm. | CZSST | CYST7 | Fabaceae |
| Scotch broom | Cytisus scoparius (L.) Link | SAOSC | CYSC4 | Fabaceae |
| Spanish broom | Spartium junceum L. | SPUJU | SPJU2 | Fabaceae |
| branched broomrape | Phelipanche ramosa (L.) Pomel | ORARA | Orobanchaceae | |
| Cooper broomrape | Orobanche cooperi (A. Gray) A. Heller | ORACO | ORCO4 | Orobanchaceae |
| crenate broomrape | Orobanche crenata Forssk. | ORACR | ORCR | Orobanchaceae |
| Louisiana broomrape | Orobanche ludoviciana Nutt. | ORALU | ORLU | Orobanchaceae |
| nodding broomrape | Orobanche cernua Loefl. | ORACE | ORCE | Orobanchaceae |
| small broomrape | Orobanche minor Sm. | ORAMI | ORMI | Orobanchaceae |
| broomsedge | Andropogon virginicus L. | ANOVI | ANVI2 | Poaceae |
| common broomweed | Amphiachyris dracunculoides (DC.) Nutt. | GUEDR | AMDR | Asteraceae |
| browneyed Susan | Rudbeckia triloba L. | RUDTR | RUTR2 | Asteraceae |
| white bryony | Bryonia alba L. | BYOAL | BRAL4 | Cucurbitaceae |
| buckbrush | Ceanothus cuneatus (Hook.) Nutt. | CEACU | CECU | Rhamnaceae |
| alder buckthorn | Frangula alnus Mill. | RHAFR | FRAL4 | Rhamnaceae |
| European buckthorn | Rhamnus cathartica L. | RHACT | RHCA3 | Rhamnaceae |
| buckwheat | Fagopyrum esculentum Moench | FAGES | FAES2 | Polygonaceae |
| annual buckwheat | Eriogonum annuum Nutt. | ERGAN | ERAN4 | Polygonaceae |
| flatcrown buckwheat | Eriogonum deflexum Torr. | ERGDE | ERDE6 | Polygonaceae |
| Tartary buckwheat | Fagopyrum tataricum (L.) Gaertn. | FAGTA | FATA | Polygonaceae |
| wild buckwheat | Fallopia convolvulus (L.) Á. Löve | POLCO | FACO | Polygonaceae |
| russet buffaloberry | Shepherdia canadensis (L.) Nutt. | SHPCA | SHCA | Elaeagnaceae |
| buffalobur | Solanum rostratum Dunal | SOLRS | SORO | Solanaceae |
| buffalograss | Bouteloua dactyloides (Nutt.) Columbus | BUDCA | BODA2 | Poaceae |
| false buffalograss | Munroa squarrosa (Nutt.) Torr. | MUOSQ | MOSQ | Poaceae |
| buffelgrass | Pennisetum ciliare (L.) Link | PESCI | PECI | Poaceae |
| buffpetal | Rhynchosida physocalyx (A. Gray) Fryxell | SIDPH | RHPH2 | Malvaceae |
| carpet bugle | Ajuga reptans L. | AIURE | AJRE | Lamiaceae |
| Geneva bugle | Ajuga genevensis L. | AIUGE | AJGE | Lamiaceae |
| American bugleweed | Lycopus americanus Muhl. ex W. P. C. Barton | LYAAM | LYAM | Lamiaceae |
| European bugleweed | Lycopus europaeus L. | LYAEU | LYEU | Lamiaceae |
| rough bugleweed | Lycopus asper Greene | LYAAS | LYAS | Lamiaceae |
| slender bugleweed | Lycopus uniflorus Michx. | LYAUN | LYUN | Lamiaceae |
| common bugloss | Anchusa officinalis L. | ANCOF | ANOF | Boraginaceae |
| Italian bugloss | Anchusa azurea Mill. | ANCIT | ANAZ | Boraginaceae |
| small bugloss | Anchusa arvensis (L.) M. Bieb. | LYCAR | ANAR16 | Boraginaceae |
| vipers bugloss | Echium plantagineum L. | EHIPL | ECPL | Boraginaceae |
| American bugseed | Corispermum americanum (Nutt.) Nutt. | CRQAM | COAM8 | Chenopodiaceae |
| hairy bugseed | Corispermum villosum Rydb. | CRQVI | COVI5 | Chenopodiaceae |
| bullnettle | Cnidoscolus stimulosus (Michx.) Engelm. & A. Gray | CXFST | CNST | Euphorbiaceae |
| Texas bullnettle | Cnidoscolus texanus (Muell.-Arg.) Small | CXFTE | CNTE | Euphorbiaceae |
| black bulrush | Scirpus atrovirens Willd. | SCPAT | SCAT2 | Cyperaceae |
| California bulrush | Schoenoplectus californicus (C.A. Mey.) Palla | SCPCA | SCCA11 | Cyperaceae |
| hardstem bulrush | Schoenoplectus acutus (Muhl. ex Bigelow) A.& D. Löve | SCPAC | SCAC3 | Cyperaceae |
| keeled bulrush | Isolepis carinata Hook. & Arn. ex Torr. | SCPKL | ISCA6 | Cyperaceae |
| lined bulrush | Scirpus pendulus Muhl. | SCPPE | SCPE4 | Cyperaceae |
| ricefield bulrush | Schoenoplectiella mucronata (L.) J. Jung & H. K. Choi | SCPMU | SCMU15 | Cyperaceae |
| river bulrush | Bolboschoenus fluviatilis (Torr.) Soják | SCPFV | BOFL3 | Cyperaceae |
| softstem bulrush | Schoenoplectus tabernaemontani (K. C. Gmel.) Palla | SCPTA | SCTA2 | Cyperaceae |
| woolgrass bulrush | Scirpus cyperinus (L.) Kunth | SCPCY | SCCY | Cyperaceae |
| bunchberry | Cornus canadensis L. | CRWCA | COCA13 | Cornaceae |
| Illinois bundleflower | Desmanthus illinoensis (Michx.) MacMill. ex B. L. Rob. & Fernald | DEMIL | DEIL | Fabaceae |
| crested bunias | Bunias erucago L. | BUNER | BUER | Brassicaceae |
| California burclover | Medicago polymorpha L. | MEDPO | MEPO3 | Fabaceae |
| little burclover | Medicago minima (L.) Bartal. | MEDMI | MEMI | Fabaceae |
| spotted burclover | Medicago arabica (L.) Huds. | MEDAB | MEAR | Fabaceae |
| burcucumber | Sicyos angulatus L. | SIYAN | SIAN | Cucurbitaceae |
| common burdock | Arctium minus (Hill) Bernh. | ARFMI | ARMI2 | Asteraceae |
| great burdock | Arctium lappa L. | ARFLA | ARLA3 | Asteraceae |
| woolly burdock | Arctium tomentosum P. Mill. | ARFTO | ARTO | Asteraceae |
| bur gherkin | Cucumis anguria L. | CUMAN | CUAN | Cucurbitaceae |
| creeping burhead | Echinodorus cordifolius (L.) Griseb. | ECOCO | ECCO3 | Alismataceae |
| upright burhead | Echinodorus berteroi (Spreng.) Fassett | ECOBE | ECBE2 | Alismataceae |
| burmareed | Neyraudia reynaudiana (Kunth) Keng ex Hitchc. | NEYRE | NERE | Poaceae |
| smooth beggarticks | Bidens laevis (L.) Britton, Sterns & Poggenb. | BIDLA | BILA | Asteraceae |
| great burnet | Sanguisorba officinalis L. | SANOF | SAOF3 | Rosaceae |
| prairie burnet | Sanguisorba annua (Nutt. ex Hook.) Nutt. ex Torr. & A. Gray | QODAN | SAAN2 | Rosaceae |
| salad burnet | Sanguisorba minor Scop. | SANMI | SAMI3 | Rosaceae |
| burnet saxifrage | Pimpinella saxifraga L. | PIMSA | PISA | Apiaceae |
| winged burningbush | Euonymus alatus (Thunb.) Siebold | EUOAL | EUAL13 | Celastraceae |
| American burnweed | Erechtites hieraciifolius (L.) Raf. ex DC. | EREHI | ERHI12 | Asteraceae |
| Australian burnweed | Senecio minimus Poir. | EREPR | Asteraceae | |
| cutleaf burnweed | Erechtites glomeratus (Desf. ex Poir.) DC. | ERGL11 | Asteraceae | |
| branched burreed | Sparganium erectum L. | SPGER | SPER | Typhaceae |
| giant burreed | Sparganium eurycarpum Engelm. | SPGEU | SPEU | Typhaceae |
| greenfruit burreed | Sparganium erectum L. ssp. stoloniferum (Graebn.) H. Hara | SPGES | SPERS2 | Typhaceae |
| narrowleaf burreed | Sparganium angustifolium Michx. | SPGAN | SPAN2 | Typhaceae |
| threesquare burreed | Sparganium americanum Nutt. | SPGAM | SPAM | Typhaceae |
| water burreed | Sparganium fluctuans (Engelm. ex Morong) B. L. Rob. | SPGFL | SPFL | Typhaceae |
| annual bursage | Ambrosia acanthicarpa Hook. | FRSAC | AMAC2 | Asteraceae |
| skeletonleaf bursage | Ambrosia tomentosa Nutt. | FRSTO | AMTO3 | Asteraceae |
| slimleaf bursage | Ambrosia confertiflora DC. | FRSCO | AMCO3 | Asteraceae |
| woollyleaf bursage | Ambrosia grayi (A. Nelson) Shinners | AMBGR | AMGR5 | Asteraceae |
| lawn burweed | Soliva sessilis Ruiz & Pav. | SOVSE | SOSE2 | Asteraceae |
| bellyache bush | Jatropha gossypifolia L. | IATGO | JAGO | Euphorbiaceae |
| birdfoot buttercup | Ranunculus orthorhynchus Hook. | RANOR | RAOR3 | Ranunculaceae |
| bulbous buttercup | Ranunculus bulbosus L. | RANBU | RABU | Ranunculaceae |
| bur buttercup | Ceratocephala testiculata (Crantz) Roth | CCFTE | CETE5 | Ranunculaceae |
| California buttercup | Ranunculus californicus Benth. | RANCF | RACA2 | Ranunculaceae |
| corn buttercup | Ranunculus arvensis L. | RANAR | RAAR3 | Ranunculaceae |
| creeping buttercup | Ranunculus repens L. | RANRE | RARE3 | Ranunculaceae |
| crowfoot buttercup | Ranunculus sceleratus L. | RANSC | RASC3 | Ranunculaceae |
| hairy buttercup | Ranunculus sardous Crantz | RANSA | RASA | Ranunculaceae |
| roughseed buttercup | Ranunculus muricatus L. | RANMU | RAMU2 | Ranunculaceae |
| shore buttercup | Halerpestes cymbalaria (Pursh) Greene | RANCY | HACY2 | Ranunculaceae |
| smallflower buttercup | Ranunculus abortivus L. | RANAB | RAAB | Ranunculaceae |
| smallflower buttercup | Ranunculus parviflorus L. | RANPF | RAPA3 | Ranunculaceae |
| tall buttercup | Ranunculus acris L. | RANAC | RAAC3 | Ranunculaceae |
| western field buttercup | Ranunculus occidentalis Nutt. | RANOC | RAOC | Ranunculaceae |
| orange eye butterflybush | Buddleja davidii Franch. | BUDDA | BUDA2 | Scrophulariaceae |
| buttonbush | Cephalanthus occidentalis L. | CPLOC | CEOC2 | Rubiaceae |
| coat buttons | Tridax procumbens L. | TRQPR | TRPR5 | Asteraceae |
| broadleaf buttonweed | Spermacoce alata Aubl. | BOILF | SPAL3 | Rubiaceae |
| smooth false buttonweed | Spermacoce glabra Michx. | SPCGL | SPGL2 | Rubiaceae |
| Virginia buttonweed | Diodia virginiana L. | DIQVI | DIVI3 | Rubiaceae |
| cabbage tree | Cordyline australis Hook. f. | CDLAU | COAU12 | Asparagaceae |
| Mediterranean cabbage | Brassica fruticulosa Cirillo | BRSFR | BRFR3 | Brassicaceae |
| steppe cabbage | Rapistrum perenne (L.) All. | RASPE | RAPE4 | Brassicaceae |
| spiny tree cactus | Cereus hildmannianus K. Schum. | CEEHI | CEHI3 | Cactaceae |
| cadillo | Urena lobata L. | URNLO | URLO | Malvaceae |
| lesser calamint | Clinopodium nepeta (L.) Kuntze | STICA | CANEN | Lamiaceae |
| calamus | Acorus calamus L. | ACSCA | ACCA4 | Acoraceae |
| camelthorn | Alhagi maurorum Medik. | ALHPS | ALMA12 | Fabaceae |
| camphorweed | Heterotheca subaxillaris (Lam.) Britton & Rusby | HTTSU | HESU3 | Asteraceae |
| biennial campion | Silene csereii Baumg. | SILCS | SICS | Caryophyllaceae |
| bladder campion | Silene vulgaris (Moench) Garcke | SILVU | SIVU | Caryophyllaceae |
| meadow campion | Silene flos-cuculi (L.) Greuter & Burdet | LYHFC | SIFL5 | Caryophyllaceae |
| red campion | Silene dioica (L.) Clairv. | MELRU | SIDI4 | Caryophyllaceae |
| rose campion | Lychnis coronaria (L.) Desr. | LYHCO | LYCO | Caryophyllaceae |
| rose campion | Silene coronaria (L.) Clairv. | LYHCO | SICO15 | Caryophyllaceae |
| white campion | Silene latifolia Poir. | MELAL | SILA21 | Caryophyllaceae |
| canarygrass | Phalaris canariensis L. | PHACA | PHCA5 | Poaceae |
| Carolina canarygrass | Phalaris caroliniana Walt. | PHACL | PHCA6 | Poaceae |
| hood canarygrass | Phalaris paradoxa L. | PHAPA | PHPA5 | Poaceae |
| littleseed canarygrass | Phalaris minor Retz. | PHAMI | PHMI3 | Poaceae |
| reed canarygrass | Phalaris arundinacea L. | TYPAR | PHAR3 | Poaceae |
| shortspike canarygrass | Phalaris brachystachys Link | PHABR | PHBR3 | Poaceae |
| timothy canarygrass | Phalaris angusta Nees ex Trin. | PHAAN | PHAN2 | Poaceae |
| canker root | Coptis trifolia (L.) Salisb. | CPXTR | COTR2 | Ranunculaceae |
| canna | Canna flaccida Salisb. | CNNFL | CAFL11 | Cannaceae |
| glandular cape marigold | Dimorphotheca sinuata DC. | DMPSI | DISI4 | Asteraceae |
| capeweed | Arctotheca calendula (L.) Levyns | AROCA | ARCA45 | Asteraceae |
| caraway | Carum carvi L. | CRYCA | CACA19 | Apiaceae |
| cardinalflower | Lobelia cardinalis L. | LOBCA | LOCA2 | Campanulaceae |
| blue cardinal flower | Lobelia siphilitica L. | LOBSI | LOSI | Campanulaceae |
| Geraldton carnation weed | Euphorbia terracina L. | EPHTE | EUTE10 | Euphorbiaceae |
| carpenters square | Scrophularia marilandica L. | SCUMA | SCMA2 | Scrophulariaceae |
| carpetgrass | Axonopus fissifolius (Raddi) Kuhlm. | AXOAF | AXFI | Poaceae |
| big carpetgrass | Axonopus furcatus (Flueggé) Hitchc. | AXOFU | AXFU | Poaceae |
| carpetweed | Mollugo verticillata L. | MOLVE | MOVE | Molluginaceae |
| southwestern carrot | Daucus pusillus Michx. | DAUPU | DAPU3 | Apiaceae |
| wild carrot | Daucus carota L. | DAUCA | DACA6 | Apiaceae |
| carrotwood | Cupaniopsis anacardioides (A. Rich.) Radik. | CJQAN | CUAN4 | Sapindaceae |
| cascara buckthorn | Frangula purshiana (DC.) A. Gray | RHAPU | FRPU7 | Rhamnaceae |
| Coves cassia | Senna covesii (A. Gray) H. S. Irwin & Barneby | SJNCV | SECO10 | Fabaceae |
| castorbean | Ricinus communis L. | RIICO | RICO3 | Euphorbiaceae |
| southern catalpa | Catalpa bignonioides Walter | CTLBI | CABI8 | Bignoniaceae |
| catbriar | Smilax bona-nox L. | SMIBN | SMBO2 | Smilacaceae |
| cone catchfly | Silene conoidea L. | SILCD | SICO4 | Caryophyllaceae |
| English catchfly | Silene gallica L. | SILGA | SIGA | Caryophyllaceae |
| garden catchfly | Silene armeria L. | SILAR | SIAR | Caryophyllaceae |
| German catchfly | Silene viscaria (L.) Borkh. | LYHVI | SIVI8 | Caryophyllaceae |
| hairy catchfly | Silene dichotoma Ehrh. | SILDI | SIDI2 | Caryophyllaceae |
| nightflowering catchfly | Silene noctiflora L. | MELNO | SINO | Caryophyllaceae |
| nodding catchfly | Silene pendula L. | SILPE | SIPE3 | Caryophyllaceae |
| sand catchfly | Silene conica L. | SILCN | SICO3 | Caryophyllaceae |
| sleepy catchfly | Silene antirrhina L. | SILAN | SIAN2 | Caryophyllaceae |
| catchfly grass | Leersia lenticularis Michx. | LERLE | LELE2 | Poaceae |
| catchweed | Asperugo procumbens L. | ASGPR | ASPR | Boraginaceae |
| catclaw-vine | Dolichandra unguis-cati (L.) L. G. Lohmann | BIGUC | Bignoniaceae | |
| catnip | Nepeta cataria L. | NEPCA | NECA2 | Lamiaceae |
| common catsear | Hypochaeris radicata L. | HRYRA | HYRA3 | Asteraceae |
| smooth catsear | Hypochaeris glabra L. | HRYGL | HYGL2 | Asteraceae |
| annual catstail | Rostraria cristata (L.) Tzvelev | LPHCR | ROCR3 | Poaceae |
| blue cattail | Typha x glauca Godr. (pro sp.) [angustifolia or domingensis × latifolia] | TYHGL | TYGL | Typhaceae |
| common cattail | Typha latifolia L. | TYHLA | TYLA | Typhaceae |
| narrowleaf cattail | Typha angustifolia L. | TYHAN | TYAN | Typhaceae |
| southern cattail | Typha domingensis Pers. | TYHDO | TYDO | Typhaceae |
| greater celandine | Chelidonium majus L. | CHQMA | CHMA2 | Papaveraceae |
| lesser celandine | Ficaria verna Huds. | FICVE | FIVE2 | Ranunculaceae |
| wild celery | Cyclospermum leptophyllum (Pers.) Sprague ex Britton & P. Wilson | APULE | CYLE7 | Apiaceae |
| silver cocks comb | Celosia argentea L. | CEOAR | CEAR3 | Amaranthaceae |
| ceniza | Leucophyllum frutescens (Berland.) I. M. Johnst. | LCPFR | LEFR3 | Scrophulariaceae |
| erect centella | Centella erecta (L. f.) Fernald | CLLAS | CEER2 | Apiaceae |
| centipede grass | Eremochloa ophiuroides (Munro) Hack. | ERLOP | EROP | Poaceae |
| Japanese chaff flower | Achyranthes japonica (Miq.) Nakai | ACYJA | ACJA | Amaranthaceae |
| mat chaff-flower | Alternanthera caracasana Kunth | ALRPE | ALCA5 | Amaranthaceae |
| chamber bitter | Phyllanthus urinaria L. | PYLUR | PHUR | Phyllanthaceae |
| corn chamomile | Anthemis arvensis L. | ANTAR | ANAR6 | Asteraceae |
| mayweed chamomile | Anthemis cotula L. | ANTCO | AMCO2 | Asteraceae |
| Roman chamomile | Chamaemelum nobile (L.) All. | ANTNO | CHNO3 | Asteraceae |
| scentless chamomile | Tripleurospermum inodorum (L.) Sch. Bip. | MATIN | TRIN11 | Asteraceae |
| wild chamomile | Matricaria chamomilla L. | MATCH | MACH2 | Asteraceae |
| yellow chamomile | Anthemis tinctoria L. | ANTTI | ANTI | Asteraceae |
| chaparral | Larrea divaricata Cav. | LARDI | LADI2 | Zygophyllaceae |
| lilac chastetree | Vitex agnus-castus L. | VIXAC | VIAG | Verbenaceae |
| cheat | Bromus secalinus L. | BROSE | BRSE | Poaceae |
| black cherry | Prunus serotina Ehrh. | PRNSO | PRSE2 | Rosaceae |
| European bird cherry | Prunus padus L. | PRNPA | PRPA5 | Rosaceae |
| Mahaleb cherry | Prunus mahaleb L. | PRNMH | PRMA | Rosaceae |
| pin cherry | Prunus pensylvanica L. f. | PRNPE | PRPE2 | Rosaceae |
| sour cherry | Prunus cerasus L. | PRNCE | PRCE | Rosaceae |
| sweet cherry | Prunus avium (L.) L. | PRNAV | PRAV | Rosaceae |
| chervil | Anthriscus cerefolium (L.) Hoffm. | ANRCE | ANCE | Apiaceae |
| bur chervil | Anthriscus caucalis M. Bieb. | ANRCA | ANCA14 | Apiaceae |
| hairyfruit chervil | Chaerophyllum tainturieri Hook. | CHPTA | CHTA | Apiaceae |
| wild chervil | Anthriscus sylvestris (L.) Hoffm. | ANRSY | ANSY | Apiaceae |
| Australian chess | Bromus arenarius Labill. | BROAR | BRAR3 | Poaceae |
| hairy chess | Bromus commutatus Schrad. | BROCO | BRCO4 | Poaceae |
| Alaska chickweed | Stellaria longipes Goldie | STELA | STLO2 | Caryophyllaceae |
| big chickweed | Cerastium fontanum Baumg. | CERFO | CEFO2 | Caryophyllaceae |
| common chickweed | Stellaria media (L.) Vill. | STEME | STME2 | Caryophyllaceae |
| field chickweed | Cerastium arvense L. | CERAR | CEAR4 | Caryophyllaceae |
| mouseear chickweed | Cerastium fontanum Baumg. ssp. vulgare (Hartm.) Greuter & Burdet | CERVU | CEFOV2 | Caryophyllaceae |
| nodding chickweed | Cerastium nutans Raf. | CERNU | CENU2 | Caryophyllaceae |
| shortstalk chickweed | Cerastium brachypodum (Engelm. ex A. Gray) B. L. Rob. | CERBP | CEBR3 | Caryophyllaceae |
| star chickweed | Stellaria pubera Michx. | STEPB | STPU | Caryophyllaceae |
| sticky chickweed | Cerastium glomeratum Thuill. | CERGL | CEGL2 | Caryophyllaceae |
| chicory | Cichorium intybus L. | CICIN | CIIN | Asteraceae |
| chinaberry | Melia azedarach L. | MEIAZ | MEAZ | Meliaceae |
| Chinese lantern plant | Physalis alkekengi L. | PHYAL | PHAL5 | Solanaceae |
| bush chinquapin | Chrysolepis sempervirens (Kellogg) Hjelmq. | CSOSE | CHSE11 | Fagaceae |
| giant chinquapin | Chrysolepis chrysophylla (Douglas ex Hook.) Hjelmq. | CSOCH | CHCH7 | Fagaceae |
| fringed chloris | Chloris ciliata Sw. | CHRCI | CHCI | Poaceae |
| black chokecherry | Prunus virginiana L. var. melanocarpa (A. Nelson) Sarg. | PRNVM | PRVIM | Rosaceae |
| common chokecherry | Prunus virginiana L. | PRNVG | PRVI | Rosaceae |
| western chokecherry | Prunus virginiana L. var. demissa (Nutt.) Torr. | PRNVD | PRVID | Rosaceae |
| jumping cholla | Cylindropuntia fulgida (Engelm.) F. M. Knuth | OPUFU | CYFU10 | Cactaceae |
| staghorn cholla | Cylindropuntia versicolor (Engelm. ex J. M. Coult.) F. M. Knuth | OPUVE | CYVE3 | Cactaceae |
| walkingstick cholla | Cylindropuntia imbricata (Haw.) F. M. Knuth | OPUIM | CYIMI | Cactaceae |
| biennial cinquefoil | Potentilla biennis Greene | PTLBN | POBI7 | Rosaceae |
| bush cinquefoil | Dasiphora floribunda (Pursh) Raf. | PTLFF | DAFL3 | Rosaceae |
| bush cinquefoil | Dasiphora fruticosa (L.) Rydb. ssp. floribunda (Pursh) Kartesz | PTLFF | DAFRF | Rosaceae |
| creeping cinquefoil | Potentilla reptans L. | PTLRE | PORE6 | Rosaceae |
| downy cinquefoil | Potentilla intermedia L. | PTLIN | POIN8 | Rosaceae |
| dwarf cinquefoil | Potentilla canadensis L. | PTLCA | POCA17 | Rosaceae |
| oldfield cinquefoil | Potentilla simplex Michx. | PTLSI | POSI2 | Rosaceae |
| rough cinquefoil | Potentilla norvegica L. | PTLNO | PONO3 | Rosaceae |
| shrubby cinquefoil | Dasiphora fruticosa (L.) Rydb. | PTLFR | DAFR6 | Rosaceae |
| silverweed cinquefoil | Potentilla anserina L. | PTLAN | POAN5 | Rosaceae |
| silver cinquefoil | Potentilla argentea L. | PTLAG | POAR8 | Rosaceae |
| slender cinquefoil | Potentilla gracilis Dougl. ex Hook. | PTLGR | POGR9 | Rosaceae |
| sticky cinquefoil | Potentilla glandulosa Lindl. | PTLGL | POGL9 | Rosaceae |
| sulfur cinquefoil | Potentilla recta L. | PTLRC | PORE5 | Rosaceae |
| three toothed cinquefoil | Potentilla tridentata Aiton | PTLTR | POTR7 | Rosaceae |
| white cinquefoil | Potentilla arguta Pursh | PTLAR | POAR7 | Rosaceae |
| citronmelon | Citrullus lanatus (Thunb.) Matsum. & Nakai var. citroides (L. H. Bailey) Mansf. | CITLC | CILAC | Cucurbitaceae |
| roughseed clammyweed | Polanisia dodecandra (L.) DC. | PONGR | PODO3 | Cleomaceae |
| western clammyweed | Polanisia dodecandra (L.) DC. ssp. trachysperma (Torr. & A. Gray) H. H. Iltis | PONTR | PODOT | Cleomaceae |
| Balkan clary | Salvia x sylvestris L. (pro sp.) [nemorosa × pratensis] | SALSV | SASY | Lamiaceae |
| clearweed | Pilea pumila (L.) A. Gray | PILPU | PIPU2 | Urticaceae |
| false cleavers | Galium spurium L. | GALSP | GASP3 | Rubiaceae |
| Chinese clematis | Clematis orientalis L. | CLVOR | CLOR | Ranunculaceae |
| golden clematis | Clematis tangutica (Maxim.) Korsh. | CLTVA | CLTA2 | Ranunculaceae |
| western clematis | Clematis ligusticifolia Nutt. | CLVLI | CLLI2 | Ranunculaceae |
| Japanese climbing fern | Lygodium japonicum (Thunb.) Sw. | LYFJA | LYJA | Lygodiaceae |
| old world climbing fern | Lygodium microphyllum (Cav.) R. Br. | LYFMI | LYMI | Lygodiaceae |
| alsike clover | Trifolium hybridum L. | TRFHY | TRHY | Fabaceae |
| bear clover | Chamaebatia foliolosa Benth. | CHMFO | CHFO | Rosaceae |
| buffalo clover | Trifolium reflexum L. | TRFRF | TRRE2 | Fabaceae |
| clustered clover | Trifolium glomeratum L. | TRFGL | TRGL4 | Fabaceae |
| cow clover | Trifolium wormskioldii Lehm. | TRFWO | TRWO | Fabaceae |
| crimson clover | Trifolium incarnatum L. | TRFIN | TRIN3 | Fabaceae |
| hop clover | Trifolium aureum Pollich | TRFAU | TRAU2 | Fabaceae |
| large hop clover | Trifolium campestre Schreb. | TRFCA | TRCA5 | Fabaceae |
| narrowleaved clover | Trifolium angustifolium L. | TRFAN | TRAN6 | Fabaceae |
| rabbitfoot clover | Trifolium arvense L. | TRFAR | TRAR4 | Fabaceae |
| red clover | Trifolium pratense L. | TRFPR | TRPR2 | Fabaceae |
| rose clover | Trifolium hirtum All. | TRFHI | TRHI4 | Fabaceae |
| small hop clover | Trifolium dubium Sibth. | TRFDU | TRDU2 | Fabaceae |
| strawberry clover | Trifolium fragiferum L. | TRFFR | TRFR2 | Fabaceae |
| subterranean clover | Trifolium subterraneum L. | TRFSU | TRSU3 | Fabaceae |
| white clover | Trifolium repens L. | TRFRE | TRRE3 | Fabaceae |
| Cuban club rush | Oxycaryum cubense (Poepp. & Kunth) Lye | SCPCU | OXCU2 | Cyperaceae |
| clusterflower | Flaveria trinervia (Spreng.) C. Mohr | FLATN | FLTR | Asteraceae |
| corn cockle | Agrostemma githago L. | AGOGI | AGGI | Caryophyllaceae |
| Canada cocklebur | Xanthium strumarium L. var. canadense (Mill.) Torr. & A. Gray | XANSI | XASTC | Asteraceae |
| common cocklebur | Xanthium strumarium L. | XANST | XAST | Asteraceae |
| spiny cocklebur | Xanthium spinosum L. | XANSP | XASP2 | Asteraceae |
| coast cockspur | Echinochloa walteri (Pursh) A. Heller | ECHWA | ECWA | Poaceae |
| gulf cockspur | Echinochloa crus-pavonis (Kunth) J.A. Schultes | ECHCV | ECCR2 | Poaceae |
| California buckthorn | Frangula californica (Eschsch.) A. Gray | RHACA | FRCA12 | Rhamnaceae |
| red buckthorn | Frangula rubra (Greene) Grubov | FGLRU | FRRU | Rhamnaceae |
| cogongrass | Imperata cylindrica (L.) P. Beauv. | IMPCY | IMCY | Poaceae |
| black cohosh | Actaea racemosa L. | AATRA | ACRAR | Ranunculaceae |
| coincya | Coincya monensis (L.) Greuter & Burdet | RYNMO | COMO9 | Brassicaceae |
| colocynth | Citrullus colocynthis (L.) Schrad. | CITCO | CICO7 | Cucurbitaceae |
| coltsfoot | Tussilago farfara L. | TUSFA | TUFA | Asteraceae |
| European columbine | Aquilegia vulgaris L. | AQIVU | AQVU | Ranunculaceae |
| common comfrey | Symphytum officinale L. | SYMOF | SYOF | Boraginaceae |
| prickly comfrey | Symphytum asperum Lepech. | SYMAS | SYAS | Boraginaceae |
| common fiddleneck | Amsinckia intermedia Fisch. & C.A. Mey. | AMSIN | AMIN3 | Boraginaceae |
| compassplant | Silphium laciniatum L. | SIPLA | SILA3 | Asteraceae |
| coneflower | Rudbeckia amplexicaulis Vahl | DRCAM | DRAM | Asteraceae |
| cutleaf coneflower | Rudbeckia laciniata L. | RUDLA | RULA3 | Asteraceae |
| hairy coneflower | Rudbeckia hirta L. | RUDHI | RUHI2 | Asteraceae |
| pinnate prairie coneflower | Ratibida pinnata (Vent.) Barnhart | RATPI | RAPI | Asteraceae |
| purple coneflower | Echinacea purpurea (L.) Moench | RUDPU | ECPU | Asteraceae |
| upright prairie coneflower | Ratibida columnifera (Nutt.) Wooton & Standl. | RATCO | RACO3 | Asteraceae |
| Coulter conyza | Laennecia coulteri (A. Gray) G. L. Nesom | LNCCO | LACO13 | Asteraceae |
| coontail | Ceratophyllum demersum L. | CEYDE | CEDE4 | Ceratophyllaceae |
| hophornbeam copperleaf | Acalypha ostryifolia Riddell | ACCOS | ACOS | Euphorbiaceae |
| New Mexico copperleaf | Acalypha neomexicana Müll. Arg. | ACCNE | ACNE | Euphorbiaceae |
| rhombic copperleaf | Acalypha rhomboidea Raf. | ACCRH | ACRH | Euphorbiaceae |
| slender copperleaf | Acalypha gracilens A. Gray | ACCGR | ACGR2 | Euphorbiaceae |
| Virginia copperleaf | Acalypha virginica L. | ACCVI | ACVI | Euphorbiaceae |
| copperweed | Oxytenia acerosa Nutt. | OXTAC | OXAC4 | Asteraceae |
| coralberry | Symphoricarpos orbiculatus Moench | SYPOR | SYOR | Caprifoliaceae |
| common cordgrass | Spartina anglica C.E. Hubbard | SPTAN | SPAN5 | Poaceae |
| denseflower cordgrass | Spartina densiflora Brongn. | SPDTE | SPDE2 | Poaceae |
| prairie cordgrass | Spartina pectinata Link | SPTPE | SPPE | Poaceae |
| saltmeadow cordgrass | Spartina patens (Aiton) Muhl. | SPTPA | SPPA | Poaceae |
| smooth cordgrass | Spartina alterniflora Loisel. | SPTAL | SPAL | Poaceae |
| garden coreopsis | Coreopsis lanceolata L. | CRLLA | COLA5 | Asteraceae |
| plains coreopsis | Coreopsis tinctoria Nutt. | CRLTI | COTI3 | Asteraceae |
| whorled coreopsis | Coreopsis verticillata L. | CRLVE | COVE5 | Asteraceae |
| coriander | Coriandrum sativum L. | CORSA | COSA | Apiaceae |
| volunteer corn | Zea mays L. | ZEAMX | ZEMA | Poaceae |
| garden cornflower | Centaurea cyanus L. | CENCY | CECY2 | Asteraceae |
| perennial cornflower | Centaurea montana L. | CENMO | CEMO | Asteraceae |
| beaked cornsalad | Valerianella radiata (L.) Dufr. | VLLRA | VARA | Caprifoliaceae |
| common cornsalad | Valerianella locusta (L.) Lat. | VLLLO | VALO | Caprifoliaceae |
| Italian cornsalad | Valerianella eriocarpa Desv. | VLLER | VAER2 | Caprifoliaceae |
| pale corydalis | Corydalis sempervirens (L.) Pers. | COYSE | COSE5 | Fumariaceae |
| costmary | Tanacetum balsamita L. | CHYBA | TABA | Asteraceae |
| orange cotoneaster | Cotoneaster franchetii Boiss. | CTTFR | COFR3 | Rosaceae |
| Parney cotoneaster | Cotoneaster coriaceus Franch. | Rosaceae | ||
| silverleaf cotoneaster | Cotoneaster pannosus Franch. | CTTPA | COPA14 | Rosaceae |
| cotton | Gossypium hirsutum L. | GOSHI | GOHI | Malvaceae |
| narrowleaf cottonrose | Logfia gallica (L.) Coss. & Germ. | FILGA | LOGA2 | Asteraceae |
| plains snakecotton | Froelichia floridana (Nutt.) Moq. | FROFL | FRFL | Amaranthaceae |
| Arizona cottontop | Digitaria californica (Benth.) Henrard | TRCCA | DICA8 | Poaceae |
| slender cottonweed | Froelichia gracilis (Hook.) Moq. | FROGR | FRGR3 | Amaranthaceae |
| common cottonwood | Populus deltoides W. Bartram ex Marshall | POPDE | PODE3 | Salicaceae |
| African couchgrass | Digitaria abyssinica (Hochst. ex A. Rich) Stapf | DIGSC | DIAB | Poaceae |
| cow poison | Delphinium trolliifolium A. Gray | DELTF | DETR2 | Ranunculaceae |
| cowcockle | Vaccaria hispanica (Mill.) Rauschert | VAAPY | VAHI2 | Caryophyllaceae |
| cow-parsnip | Heracleum sphondylium L. | HEREL | HESPM | Apiaceae |
| cowpea | Vigna unguiculata (L.) Walp. | VIGSI | VIUN | Fabaceae |
| cowwheat | Melampyrum lineare Desr. | MEALI | MELI2 | Orobanchaceae |
| coyote brush | Baccharis pilularis DC. | BACPI | BAPI | Asteraceae |
| blanket crabgrass | Digitaria serotina (Walt.) Michx. | DIGSO | DISE3 | Poaceae |
| India crabgrass | Digitaria longiflora (Retz.) Pers. | DIGLO | DILO2 | Poaceae |
| large crabgrass | Digitaria sanguinalis (L.) Scop. | DIGSA | DISA | Poaceae |
| slender crabgrass | Digitaria filiformis (L.) Koeler | DIGFI | DIFI | Poaceae |
| smooth crabgrass | Digitaria ischaemum (Schreb.) Schreb. ex Muhl. | DIGIS | DIIS | Poaceae |
| southern crabgrass | Digitaria ciliaris (Retz.) Koeler | DIGAD | DICI | Poaceae |
| tropical crabgrass | Digitaria bicornis (Lam.) Roem. & Schult. | DIGBC | DIBI | Poaceae |
| violet crabgrass | Digitaria violascens Link | DIGVI | DIVI2 | Poaceae |
| crab's-claw | Stratiotes aloides L. | STTAL | STAL6 | Hydrocharitaceae |
| longstalk cranesbill | Geranium columbinum L. | GERCO | GECO | Geraniaceae |
| Lambert crazyweed | Oxytropis lambertii Pursh | OXRLA | OXLA3 | Fabaceae |
| showy crazyweed | Oxytropis splendens Douglas ex Hook. | OXRSP | OXSP | Fabaceae |
| silky crazyweed | Oxytropis sericea Nutt. | OXRSE | OXSE | Fabaceae |
| creosote bush | Larrea tridentata (DC.) Coville | LARTR | LATR2 | Zygophyllaceae |
| garden cress | Lepidium sativum L. | LEPSA | LESA2 | Brassicaceae |
| hoary cress | Cardaria draba (L.) Desv. | CADDR | CADR | Brassicaceae |
| hoary cress | Lepidium draba L. | CADDR | LEDR | Brassicaceae |
| mouseear cress | Arabidopsis thaliana (L.) Heynh. | ARBTH | ARTH | Brassicaceae |
| shepherd's cress | Teesdalia nudicaulis (L.) R. Br. | TEENU | TENU | Brassicaceae |
| cretanweed | Hedypnois cretica (L.) Dum. Cours. | HYNCR | HECR2 | Asteraceae |
| croftonweed | Ageratina adenophora (Spreng.) R. M. King & H. Rob. | EUPAD | AGAD2 | Asteraceae |
| creeping croftonweed | Ageratina riparia (Regel) R. M. King & H. Rob. | EUPRI | AGRI2 | Asteraceae |
| crossvine | Bignonia capreolata L. | BIGCA | BICA | Bignoniaceae |
| narrowleaf crosswort | Crucianella angustifolia L. | CNLAN | CRAN11 | Rubiaceae |
| lanceleaf crotalaria | Crotalaria lanceolata E. Mey. | CVTLA | CRLA7 | Fabaceae |
| showy crotalaria | Crotalaria spectabilis Roth | CVTSP | CRSP2 | Fabaceae |
| slenderleaf crotalaria | Crotalaria brevidens Benth. var. intermedia (Kotschy) Polhill | CVTBI | CRBRI | Fabaceae |
| smooth crotalaria | Crotalaria pallida Aiton | CVTMU | CRPA10 | Fabaceae |
| prairie tea croton | Croton monanthogynus Michx. | CVNMO | CRMO6 | Euphorbiaceae |
| Texas croton | Croton texensis (Klotzsch) Müll. Arg. | CVNTE | CRTE4 | Euphorbiaceae |
| threeseed croton | Croton lindheimerianus Scheele | CVNLN | CRLI2 | Euphorbiaceae |
| tropic croton | Croton glandulosus L. var. septentrionalis Müll. Arg. | CVNGS | CRGLS | Euphorbiaceae |
| woolly croton | Croton capitatus Michx. | CVNCP | CRCA6 | Euphorbiaceae |
| crowfootgrass | Dactyloctenium aegyptium (L.) Willd. | DTTAE | DAAE | Poaceae |
| crownbeard | Verbesina encelioides (Cav.) Benth. & Hook. f. ex A. Gray | VEEEN | VEEN | Asteraceae |
| polytrichum moss | Polytrichum commune | PASFA | PAFA4 | Poaceae |
| trailing crownvetch | Securigera varia (L.) Lassen | CZRVA | SEVA4 | Fabaceae |
| common crupina | Crupina vulgaris Cass. | CJNVU | CRVU2 | Asteraceae |
| creeping cucumber | Melothria pendula L. | MEEPE | MEPE3 | Cucurbitaceae |
| wild cucumber | Echinocystis lobata (Michx.) Torr. & A. Gray | ECNLO | ECLO | Cucurbitaceae |
| clammy cudweed | Pseudognaphalium viscosum (Kunth) Anderb. | QGPVI | PSVI4 | Asteraceae |
| cottonbatting cudweed | Pseudognaphalium stramineum (Kunth) Anderb. | QGPST | PSST7 | Asteraceae |
| everlasting cudweed | Pseudognaphalium luteoalbum (L.) Hilliard & B. L. Burtt | GNALA | PSLU6 | Asteraceae |
| fragrant cudweed | Pseudognaphalium obtusifolium (L.) Hilliard & B. L. Burtt | GNAOB | PSOB3 | Asteraceae |
| low cudweed | Gnaphalium uliginosum L. | GNAUL | GNUL | Asteraceae |
| lowland cudweed | Gnaphalium palustre Nutt. | GNAPA | GNPA | Asteraceae |
| Macoun cudweed | Pseudognaphalium macounii (Greene) Kartesz | QGPMA | PSMA11 | Asteraceae |
| narrowleaf cudweed | Gamochaeta falcata (Lam.) Cabrera | GNAFA | GAFA3 | Asteraceae |
| purple cudweed | Gamochaeta purpurea (L.) Cabrera | GNAPU | GAPU3 | Asteraceae |
| wandering cudweed | Gamochaeta pensylvanica (Willd.) Cabrera | GNAPE | GAPE2 | Asteraceae |
| prairie cupgrass | Eriochloa contracta Hitchc. | ERBCO | ERCO8 | Poaceae |
| southwestern cupgrass | Eriochloa acuminata (J. Presl) Kunth | ERBGR | ERAC4 | Poaceae |
| woolly cupgrass | Eriochloa villosa (Thunb.) Kunth | ERBVI | ERVI3 | Poaceae |
| clammy cuphea | Cuphea viscosissima Jacq. | CPHPE | CUVI | Lythraceae |
| tarweed cuphea | Cuphea carthagenensis (Jacq.) J. F. Macbr. | CPHCA | CUCA4 | Lythraceae |
| cupid shaving brush | Emilia fosbergii Nicolson | EMIFO | EMFO | Asteraceae |
| common curlymesquite | Hilaria belangeri (Steud.) Nash | HILBE | HIBE | Poaceae |
| American black currant | Ribes americanum Mill. | RIBAM | RIAM2 | Grossulariaceae |
| golden currant | Ribes aureum Pursh | RIBAU | RIAU | Grossulariaceae |
| sticky currant | Ribes viscosissimum Pursh | RIBVS | RIVI3 | Grossulariaceae |
| wax currant | Ribes cereum Douglas | RIBCE | RICE | Grossulariaceae |
| giant cutgrass | Zizaniopsis miliacea (Michx.) Doll & Asch. | ZIOMI | ZIMI | Poaceae |
| rice cutgrass | Leersia oryzoides (L.) Sw. | LEROR | LEOR | Poaceae |
| southern cutgrass | Leersia hexandra Sw. | LERHE | LEHE | Poaceae |
| African daisy | Osteospermum ecklonis (DC.) Norl. | OSPEK | OSEC | Asteraceae |
| crown daisy | Glebionis coronaria (L.) Cass. ex Spach | CHYCO | GLCO6 | Asteraceae |
| endive daisy | Rhagadiolus stellatus (L.) Gaertn. | RHGST | RHST3 | Asteraceae |
| English daisy | Bellis perennis L. | BELPE | BEPE2 | Asteraceae |
| oxeye daisy | Leucanthemum vulgare Lam. | CHYLE | LEVU | Asteraceae |
| tahoka daisy | Machaeranthera tanacetifolia (Kunth) Nees | MCATA | MATA2 | Asteraceae |
| dallisgrass | Paspalum dilatatum Poir. | PASDI | PADI3 | Poaceae |
| damesrocket | Hesperis matronalis L. | HEVMA | HEMA3 | Brassicaceae |
| dandelion | Taraxacum officinale F. H. Wigg. | TAROF | TAOF | Asteraceae |
| redseed dandelion | Taraxacum erythrospermum Andrz. ex Besser | TARER | TAER3 | Asteraceae |
| February daphne | Daphne mezereum L. | DAPME | DAME3 | Thymelaeaceae |
| Persian darnel | Lolium persicum Boiss. & Hohen. | LOLPS | LOPE2 | Poaceae |
| Canary Island date palm | Phoenix canariensis hort. ex Chabaud | PHXCA | PHCA13 | Arecaceae |
| oakleaf datura | Datura quercifolia Kunth | DATFE | DAQU | Solanaceae |
| sacred datura | Datura inoxia Mill. | DATIN | DAIN2 | Solanaceae |
| small datura | Datura discolor Bernh. | DATDI | DADI2 | Solanaceae |
| Asiatic dayflower | Commelina communis L. | COMCO | COCO3 | Commelinaceae |
| Benghal dayflower | Commelina benghalensis L. | COMBE | COBE2 | Commelinaceae |
| erect dayflower | Commelina erecta L. | COMER | COER | Commelinaceae |
| marsh dayflower | Murdannia keisak (Hassk.) Hand.-Maz. | ANEKE | MUKE | Commelinaceae |
| spreading dayflower | Commelina diffusa Burm. f. | COMDI | CODI5 | Commelinaceae |
| tawny daylily | Hemerocallis fulva (L.) L. | HEGFU | HEFU | Xanthorrhoeaceae |
| purple deadnettle | Lamium purpureum L. | LAMPU | LAPU2 | Lamiaceae |
| spotted deadnettle | Lamium maculatum L. | LAMMA | LAMA | Lamiaceae |
| foothill deathcamas | Toxicoscordion paniculatum (Nutt.) Rydb. | ZIGPA | TOPA5 | Melanthiaceae |
| grassy deathcamas | Toxicoscordion venenosum var. gramineum (Rydb.) Brasher | ZIGGR | TOGR3 | Melanthiaceae |
| meadow deathcamas | Toxicoscordion venenosum (S. Watson) Rydb. | ZIGGR | TOVE2 | Melanthiaceae |
| mountain deathcamas | Anticlea elegans (Pursh) Rydb. | ZIGEL | ANEL5 | Melanthiaceae |
| Nuttall's deathcamas | Toxicoscordion nuttallii (A. Gray) Rydb. | ZIGNU | TONU2 | Melanthiaceae |
| deerbrush | Ceanothus integerrimus Hook. & Arn. | CEAIN | CEIN3 | Rhamnaceae |
| deergrass | Muhlenbergia rigens (Benth.) Hitchc. | MUHRI | MURI2 | Poaceae |
| deervetch | Lotus unifoliolatus (Hook.) Benth. | AKMAM | LOUN | Fabaceae |
| desertbroom | Baccharis sarothroides A. Gray | BACSR | BASA2 | Asteraceae |
| cliff desertdandelion | Malacothrix saxatilis (Nutt.) Torr. & A. Gray | MCXSA | MASA2 | Asteraceae |
| Texas desert-goldenrod | Neonesomia palmeri (A. Gray) Urbatsch & R. P. Roberts | EIMAU | Asteraceae | |
| desert marigold | Baileya multiradiata Harv. & A. Gray ex Torr. | BAIMU | BAMU | Asteraceae |
| Wasatch desertparsley | Lomatium bicolor (S. Watson) J. M. Coult. & Rose var. leptocarpum (Torr. & A. Gray) Schlessman | LOMLE | LOBIL | Apiaceae |
| desert poppy | Kallstroemia grandiflora Torr. ex A. Gray | KALGR | KAGR | Zygophyllaceae |
| devils horsewhip | Achyranthes aspera L. | ACYAS | ACAS | Amaranthaceae |
| devils claw | Proboscidea louisianica (Mill.) Thell. | PROLO | PRLO | Martyniaceae |
| yellow devils claw | Ibicella lutea (Lindl.) Van Eselt. | IBILU | IBLU | Martyniaceae |
| bristly dewberry | Rubus hispidus L. | RUBHI | RUHI | Rosaceae |
| northern dewberry | Rubus flagellaris Willd. | RUBFL | RUFL | Rosaceae |
| southern dewberry | Rubus trivialis Michx. | RUBTV | RUTR | Rosaceae |
| old world diamond flower | Oldenlandia corymbosa L. | OLDCO | OLCO | Rubiaceae |
| diamondflowers | Stenaria nigricans (Lam.) Terrell | ZTENI | STNIN | Rubiaceae |
| deertongue dichanthelium | Dichanthelium clandestinum (L.) Gould | PANCL | DICL | Poaceae |
| Carolina dichondra | Dichondra carolinensis Michx. | DIORC | DICA3 | Convolvulaceae |
| kidney-weed dichondra | Dichondra micrantha Urb. | DIOMI | DIMI | Convolvulaceae |
| dill | Anethum graveolens L. | AFEGR | ANGR2 | Apiaceae |
| spiral ditchgrass | Ruppia cirrhosa (Petagna) Grande | RUPCI | RUCI2 | Ruppiaceae |
| dobie pod | Tropidocarpum gracile Hook. | TKPGR | TRGR5 | Brassicaceae |
| broadleaf dock | Rumex obtusifolius L. | RUMOB | RUOB | Polygonaceae |
| canaigre dock | Rumex hymenosepalus Torr. | RUMHS | RUHY | Polygonaceae |
| cluster dock | Rumex conglomeratus Murray | RUMCO | RUCO2 | Polygonaceae |
| curly dock | Rumex crispus L. | RUMCR | RUCR | Polygonaceae |
| fiddleleaf dock | Rumex pulcher L. | RUMPU | RUPU3 | Polygonaceae |
| field dock | Rumex pseudonatronatus Borbás | RUMPS | RUPS | Polygonaceae |
| golden dock | Rumex maritimus L. | RUMMA | RUMA4 | Polygonaceae |
| Kerner dock | Rumex kerneri Borbás | RUMKE | RUKE | Polygonaceae |
| longleaf dock | Rumex longifolius DC. | RUMLO | RULO2 | Polygonaceae |
| Mexican dock | Rumex salicifolius Weinm. var. mexicanus (Meisn.) C.L. Hitchc. | RUMSM | RUSAM | Polygonaceae |
| narrowleaf dock | Rumex stenophyllus Ledeb. | RUMST | RUST4 | Polygonaceae |
| pale dock | Rumex altissimus Alph. Wood | RUMAT | RUAL4 | Polygonaceae |
| spinach dock | Rumex patientia L. | RUMPA | RUPA5 | Polygonaceae |
| swamp dock | Rumex verticillatus L. | RUMVT | RUVE3 | Polygonaceae |
| toothed dock | Rumex dentatus L. | RUMDE | RUDE3 | Polygonaceae |
| veiny dock | Rumex venosus Pursh | RUMVE | RUVE2 | Polygonaceae |
| western dock | Rumex occidentalis S. Watson | RUMOC | RUOC3 | Polygonaceae |
| alfalfa dodder | Cuscuta suaveolens Ser. | CVCSU | CUSU | Cuscutaceae |
| Australian dodder | Cuscuta australis R. Br. | CVCAU | CUAU | Cuscutaceae |
| clover dodder | Cuscuta epithymum (L.) L. | CVCEY | CUEP | Cuscutaceae |
| field dodder | Cuscuta pentagona Engelm. | CVCPE | CUPE3 | Cuscutaceae |
| flax dodder | Cuscuta epilinum Weihe | CVCEP | CUEP2 | Cuscutaceae |
| giant dodder | Cuscuta reflexa Roxb. | CVCRE | CURE | Cuscutaceae |
| largefruit dodder | Cuscuta umbrosa Beyr. ex Hook. | CVCUB | CUUM2 | Cuscutaceae |
| largeseed dodder | Cuscuta indecora Choisy | CVCIN | CUIN | Cuscutaceae |
| Peruvian dodder | Cuscuta obtusiflora Kunth | CVCAU | CUOB | Cuscutaceae |
| smartweed dodder | Cuscuta polygonorum Engelm. | CVCPO | CUPO | Cuscutaceae |
| Sandwich dodder | Cuscuta sandwichiana Choisy | CVCSA | CUSA2 | Cuscutaceae |
| smallseed dodder | Cuscuta planiflora Ten. | CVCPL | CUPL2 | Cuscutaceae |
| smallseed alfalfa dodder | Cuscuta approximata Bab. | CVCAP | CUAP2 | Cuscutaceae |
| swamp dodder | Cuscuta gronovii Willd. ex Schult. | CVCGR | CUGR | Cuscutaceae |
| umbrella dodder | Cuscuta umbellata Kunth | CVCUM | CUUM | Cuscutaceae |
| climbing dogbane | Trachelospermum difforme (Walt.) A. Gray | TCHDI | TRDI | Apocynaceae |
| hemp dogbane | Apocynum cannabinum L. | APCCA | APCA | Apocynaceae |
| spreading dogbane | Apocynum androsaemifolium L. | APCAN | APAN2 | Apocynaceae |
| dogfennel | Eupatorium capillifolium (Lam.) Small | EUPCP | EUCA5 | Asteraceae |
| crested dogtail grass | Cynosurus cristatus L. | CYXCR | CYCR | Poaceae |
| hedgehog dogtail grass | Cynosurus echinatus L. | CYXEC | CYEC | Poaceae |
| flowering dogwood | Cornus florida L. | CRWFL | COFL2 | Cornaceae |
| mountain dogwood | Cornus nuttallii Audubon ex Torr. & A. Gray | CRWNU | CONU4 | Cornaceae |
| roughleaf dogwood | Cornus drummondii C. A. Mey. | CRWDR | CODR | Cornaceae |
| dopatrium | Dopatrium junceum (Roxb.) Buch.-Ham. ex Benth. | DOPJU | DOJU | Plantaginaceae |
| doveweed | Murdannia nudiflora (L.) Brenan | MUDNU | MUNU | Commelinaceae |
| American dragonhead | Dracocephalum parviflorum Nutt. | DRAPA | DRPA2 | Lamiaceae |
| thymeleaf dragonhead | Dracocephalum thymiflorum L. | DRATH | DRTH | Lamiaceae |
| African dropseed | Sporobolus indicus var. capensis Engelm. | SPZAF | SPINC3 | Poaceae |
| annual dropseed | Sporobolus neglectus Nash | SPZNE | SPNE2 | Poaceae |
| coral dropseed | Sporobolus domingensis (Trin.) Kunth | SPZDO | SPDO2 | Poaceae |
| pineywoods dropseed | Sporobolus junceus (P. Beauv.) Kunth | SPZJU | SPJU | Poaceae |
| poverty dropseed | Sporobolus vaginiflorus (Torr. ex A. Gray) Alph. Wood | SPZVA | SPVA | Poaceae |
| sand dropseed | Sporobolus cryptandrus (Torr.) A. Gray | SPZCR | SPCR | Poaceae |
| seashore dropseed | Sporobolus virginicus (L.) Kunth | SPZVI | SPVI3 | Poaceae |
| dropwort | Filipendula vulgaris Moench | FIIVU | FIVU | Rosaceae |
| heartleaf drymary | Drymaria cordata (L.) Willd. ex Schult. | DRYCO | DRCO2 | Caryophyllaceae |
| ducklettuce | Ottelia alismoides (L.) Pers. | OTEAL | OTAL | Hydrocharitaceae |
| duckmeal | Lemna perpusilla Torr. | LEMPA | LEPE | Araceae |
| ducksalad | Heteranthera limosa (Sw.) Willd. | HETLI | HELI2 | Pontederiaceae |
| common duckweed | Lemna minor L. | LEMMI | LEMI3 | Araceae |
| giant duckweed | Spirodela polyrhiza (L.) Schleid. | SPIPO | SPPO8 | Araceae |
| inflated duckweed | Lemna gibba L. | LEMGI | LEGI | Araceae |
| lesser duckweed | Lemna aequinoctialis Welw. | LEMTN | LEAE2 | Araceae |
| minute duckweed | Lemna minuta Kunth | LEMMT | LEMI6 | Araceae |
| obscure duckweed | Lemna obscura (Austin) Daubs | LEMOB | LEOB2 | Araceae |
| small duckweed | Lemna valdiviana Phil. | LEMVA | LEVA | Araceae |
| star duckweed | Lemna trisulca L. | LEMTR | LETR | Araceae |
| Virginia dwarfdandelion | Krigia virginica (L.) Willd. | KRIVI | KRVI | Asteraceae |
| pale echinacea | Echinacea pallida (Nutt.) Nutt. | ECEPA | ECPA | Asteraceae |
| pine echium | Echium pininana Webb & Berthel. | EHIPI | ECPI2 | Boraginaceae |
| eclipta | Eclipta prostrata (L.) L. | ECLAL | ECPR | Asteraceae |
| American eelgrass | Vallisneria americana Michx. | VAIAM | VAAM3 | Hydrocharitaceae |
| Japanese eelgrass | Zostera japonica Asch. & Graebn. | ZOJA2 | Zosteraceae | |
| Brazilian egeria | Egeria densa Planch. | ELDDE | EGDE | Hydrocharitaceae |
| cherry elaeagnus | Elaeagnus multiflora Thunb. | ELGMU | ELMU | Elaeagnaceae |
| American elder | Sambucus nigra L. ssp. canadensis (L.) Bolli | SAMCN | SANIC4 | Adoxaceae |
| elecampane | Inula helenium L. | INUHE | INHE | Asteraceae |
| British elecampane | Inula britannica L. | INUBR | INBR | Asteraceae |
| elephantopus | Elephantopus mollis Kunth | ELPMO | ELMO5 | Asteraceae |
| tall elephantsfoot | Elephantopus elatus Bertol. | ELPEL | ELEL3 | Asteraceae |
| smooth elephantsfoot | Elephantopus nudatus A. Gray | ELPNU | ELNU | Asteraceae |
| Siberian elm | Ulmus pumila L. | ULMPU | ULPU | Ulmaceae |
| winged elm | Ulmus alata Michx. | ULMAL | ULAL | Ulmaceae |
| African elodea | Lagarosiphon major (Ridl.) Moss | LGAMA | LAMA15 | Hydrocharitaceae |
| common elodea | Elodea canadensis Michx. | ELDCA | ELCA7 | Hydrocharitaceae |
| western elodea | Elodea nuttallii (Planch.) H. St. John | ELDNU | ELNU2 | Hydrocharitaceae |
| spiny emex | Emex spinosa (L.) Campd. | EMESP | EMSP | Polygonaceae |
| eulaliagrass | Miscanthus sinensis Andersson | MISSI | MISI | Poaceae |
| European euonymus | Euonymus europaeus L. | EUOEU | EUEU4 | Celastraceae |
| manystem evax | Diaperia verna (Raf.) Morefield | EVAMU | EVVE | Asteraceae |
| common evening primrose | Oenothera biennis L. | OEOBI | OEBI | Onagraceae |
| cutleaf evening primrose | Oenothera laciniata Hill | OEOLA | OELA | Onagraceae |
| hairy evening primrose | Oenothera villosa Thunb. | OEVI | Onagraceae | |
| Hooker evening primrose | Oenothera elata Kunth | OEEL | Onagraceae | |
| northern evening primrose | Oenothera parviflora L. | OEPA5 | Onagraceae | |
| plains evening primrose | Camissonia contorta (Douglas) Kearney | OEOCO | CACO34 | Onagraceae |
| prairie evening-primrose | Oenothera albicaulis Pursh | OEOAL | OEAL | Onagraceae |
| showy evening primrose | Oenothera speciosa Nutt. | OEOSP | OESP2 | Onagraceae |
| pearly everlasting | Anaphalis margaritacea (L.) Benth. & Hook. f. | ANPMA | ANMA | Asteraceae |
| Canada eyebright | Euphrasia tetraquetra (Brèbiss.) Arrond | EPACA | EUTE8 | Orobanchaceae |
| fragrant false garlic | Nothoscordum gracile (Aiton) Stearn | NOTFR | NOGR3 | Amaryllidaceae |
| hairy false goldenaster | Heterotheca villosa (Pursh) Shinners | HTTVI | HEVI4 | Asteraceae |
| annual false brome | Brachypodium distachyon (L.) P. Beauv. | BRCDI | BRDI2 | Poaceae |
| perennial false brome | Brachypodium sylvaticum (Huds.) P. Beauv. | BRCSI | BRSY | Poaceae |
| shrubby false buttonweed | Spermacoce verticillata L. | BOIVE | SPVE2 | Rubiaceae |
| Carolina falsedandelion | Pyrrhopappus carolinianus (Walt.) DC. | PYHCA | PYCA2 | Asteraceae |
| largeseed falseflax | Camelina sativa (L.) Crantz | CMASA | CASA2 | Brassicaceae |
| smallseed falseflax | Camelina microcarpa Andrz. ex DC. | CMAMI | CAMI2 | Brassicaceae |
| California false-hellebore | Veratrum californicum Durand | VEACA | VECA2 | Melanthiaceae |
| green false-hellebore | Veratrum viride Aiton | VEAVI | VEVI | Melanthiaceae |
| American false pennyroyal | Hedeoma pulegioides (L.) Pers. | HEDPU | HEPU | Lamiaceae |
| rough false pennyroyal | Hedeoma hispida Pursh | HEDHI | HEHI | Lamiaceae |
| common falsepimpernel | Lindernia procumbens (Krock.) Philcox | LIDPY | LIPR5 | Linderniaceae |
| low falsepimpernel | Lindernia dubia (L.) Pennell | LIDDU | LIDU | Linderniaceae |
| roundleaved falsepimpernel | Lindernia grandiflora Nutt. | LIDGR | LIGR8 | Linderniaceae |
| Mexican fan palm | Washingtonia robusta H. Wendl. | WATRO | WARO | Arecaceae |
| Carolina fanwort | Cabomba caroliniana A. Gray | CABCA | CACA | Cabombaceae |
| fayatree | Morella faya (Ait.) Wilbur | MYRFA | MOFA | Myricaceae |
| African feathergrass | Pennisetum macrourum Trin. | PESMA | PEMA80 | Poaceae |
| feathertop | Pennisetum villosum R. Br. ex Fresen. | PESVI | PEVI2 | Poaceae |
| fennel | Foeniculum vulgare Mill. | FOEVU | FOVU | Apiaceae |
| cinnamon fern | Osmundastrum cinnamomeum (L.) C. Presl | OSMCI | OSCI2 | Osmundaceae |
| hay-scented fern | Dennstaedtia punctilobula (Michx.) T. Moore | DNNPU | DEPU2 | Dennstaedtiaceae |
| sensitive fern | Onoclea sensibilis L. | ONCSE | ONSE | Onocleaceae |
| water fern | Salvinia minima Baker | SAVRO | SAMI7 | Salviniaceae |
| gray fescue | Vulpia microstachys (Nutt.) Munro var. ciliata (Beal) Lonard & Gould | VLPMC | VUMIC | Poaceae |
| hair fescue | Festuca filiformis Pourr. | FESTE | FEFI | Poaceae |
| Pacific fescue | Vulpia microstachys (Nutt.) Munro var. pauciflora (Scribn. ex Beal) Lonard & Gould | VLPMP | VUMIP | Poaceae |
| rattail fescue | Vulpia myuros (L.) C.C. Gmel. | VLPMY | VUMY | Poaceae |
| red fescue | Festuca rubra L. | FESRU | FERU2 | Poaceae |
| sheep fescue | Festuca ovina L. | FESOV | FEOV | Poaceae |
| sixweeks fescue | Vulpia octoflora (Walt.) Rydb. | VLPOC | VUOC | Poaceae |
| small fescue | Vulpia microstachys (Nutt.) Monro | VLPMI | VUMI | Poaceae |
| squirreltail fescue | Vulpia bromoides (L.) Gray | VLPBR | VUBR | Poaceae |
| tall fescue | Lolium arundinaceum (Schreb.) Darbysh. | FESAR | LOAR10 | Poaceae |
| feverfew | Tanacetum parthenium (L.) Sch. Bip. | CHYPA | TAPA6 | Asteraceae |
| Jamaica feverplant | Tribulus cistoides L. | TRBCI | TRCI2 | Zygophyllaceae |
| Douglas fiddleneck | Amsinckia douglasiana A. DC. | AMSDO | AMDO | Boraginaceae |
| Menzies fiddleneck | Amsinckia menziesii (Lehm.) A. Nelson & J. F. Macbr. | AMSME | AMMEM2 | Boraginaceae |
| tarweed fiddleneck | Amsinckia lycopsoides Lehm. | AMSLY | AMLY | Boraginaceae |
| western fiddleneck | Amsinckia tessellata A. Gray | AMSTE | AMTE3 | Boraginaceae |
| Austrian fieldcress | Rorippa austriaca (Crantz) Besser | RORAU | ROAU | Brassicaceae |
| yellow fieldcress | Rorippa sylvestris (L.) Besser | RORSY | ROSY | Brassicaceae |
| fig | Ficus carica L. | FIUCA | FICA | Moraceae |
| hottentot fig | Carpobrotus edulis (L.) N. E. Br. | CBSED | CAED3 | Aizoaceae |
| lanceleaf figwort | Scrophularia lanceolata Pursh | SCULA | SCLA | Scrophulariaceae |
| broadleaf filaree | Erodium botrys (Cav.) Bertol. | EROBO | ERBO | Geraniaceae |
| redstem filaree | Erodium cicutarium (L.) L'Hér. | EROCI | ERCI6 | Geraniaceae |
| shortfruit filaree | Erodium brachycarpum (Godr.) Thell. | EROBR | ERBR14 | Geraniaceae |
| Texas filaree | Erodium texanum A. Gray | EROTE | ERTE13 | Geraniaceae |
| whitestem filaree | Erodium moschatum (L.) L'Hér. | EROMO | ERMO7 | Geraniaceae |
| feather fingergrass | Chloris virgata Sw. | CHRVI | CHVI4 | Poaceae |
| radiate fingergrass | Chloris radiata (L.) Sw. | CHRRA | CHRA | Poaceae |
| rock fingergrass | Eustachys petraea (Sw.) Desv. | ESTPE | EUPE9 | Poaceae |
| velvet fingergrass | Digitaria velutina (Forssk.) P. Beauv. | DIGVE | DIVE2 | Poaceae |
| narrowleaf firethorn | Pyracantha angustifolia (Franch.) C. K. Schneid. | PYEAN | PYAN | Rosaceae |
| fireweed | Chamerion angustifolium (L.) Holub | CHAAN | CHAN9 | Onagraceae |
| flatsedge | Cyperus odoratus L. | CYPFE | CYOD | Cyperaceae |
| brown flatsedge | Cyperus fuscus L. | CYPFU | CYFU3 | Cyperaceae |
| jointed flatsedge | Cyperus articulatus L. | CYPAR | CYAR4 | Cyperaceae |
| redroot flatsedge | Cyperus erythrorhizos Muhl. | CYPET | CYER2 | Cyperaceae |
| rice flatsedge | Cyperus iria L. | CYPIR | CYIR | Cyperaceae |
| tapertip flatsedge | Cyperus acuminatus Torr. & Hook. ex Torr. | CYPAC | CYAC2 | Cyperaceae |
| whiteedge flatsedge | Cyperus flavicomus Michx. | CYPFM | CYFL5 | Cyperaceae |
| common flax | Linum usitatissimum L. | LIUUT | LIUS | Linaceae |
| fairy flax | Linum catharticum L. | LIUCA | LICA9 | Linaceae |
| pale flax | Linum bienne Mill. | LIUBI | LIBI5 | Linaceae |
| spurge flax | Thymelaea passerina (L.) Coss. & Germ. | THBPA | THPA7 | Thymelaeaceae |
| annual fleabane | Erigeron annuus (L.) Pers. | ERIAN | ERAN | Asteraceae |
| dwarf fleabane | Erigeron divaricatus Michx. | ERIDI | ERDI12 | Asteraceae |
| hairy fleabane | Erigeron bonariensis L. | ERIBO | ERBO4 | Asteraceae |
| marsh fleabane | Tephroseris palustris (L.) Rchb. | SENCG | TEPA5 | Asteraceae |
| Oregon fleabane | Erigeron speciosus (Lindl.) DC. | ERISP | ERSP4 | Asteraceae |
| Philadelphia fleabane | Erigeron philadelphicus L. | ERIPH | ERPH | Asteraceae |
| poor robin fleabane | Erigeron pulchellus Michx. | ERIPU | ERPU | Asteraceae |
| rough fleabane | Erigeron strigosus Muhl. ex Willd. | ERIST | ERST3 | Asteraceae |
| tall fleabane | Erigeron floribundus (Kunth) Sch. Bip. | ERIFL | ERFL15 | Asteraceae |
| flixweed | Descurainia sophia (L.) Webb ex Prantl | DESSO | DESO2 | Brassicaceae |
| floatingfern | Ceratopteris pteridoides (Hook.) Hieron. | CESPT | CEPT | Pteridaceae |
| big floatingheart | Nymphoides aquatica (J. F. Gmel.) Kuntze | NYPAQ | NYAQ | Menyanthaceae |
| crested floatingheart | Nymphoides cristata (Roxb.) Kuntze | NYPCR | NYCR | Menyanthaceae |
| yellow floatingheart | Nymphoides peltata (S. G. Gmel.) Kuntze | NYPPE | NYPE | Menyanthaceae |
| Sawah flowering rush | Limnocharis flava (L.) Buchenau | LMNFL | LIFL5 | Alismataceae |
| female fluvellin | Kickxia spuria (L.) Dumort. | KICSP | KISP | Plantaginaceae |
| sharppoint fluvellin | Kickxia elatine (L.) Dumort. | KICEL | KIEL | Plantaginaceae |
| creeping fogfruit | Phyla canescens (Kunth) Greene | LIPCA | PHCA49 | Verbenaceae |
| northern fogfruit | Phyla lanceolata (Michx.) Greene | PHWLA | PHLA3 | Verbenaceae |
| wedgeleaf fogfruit | Phyla cuneifolia (Torr.) Greene | LIPCU | PHCU3 | Verbenaceae |
| foolsparsley | Aethusa cynapium L. | AETCY | AECY2 | Apiaceae |
| broadleaf forget me not | Myosotis latifolia Poir. | MYOLA | MYLA4 | Boraginaceae |
| field forget me not | Myosotis arvensis (L.) Hill | MYOAR | MYAR | Boraginaceae |
| spring forget me not | Myosotis verna Nutt. | MYOVE | MYVE | Boraginaceae |
| true forget me not | Myosotis scorpioides L. | MYOPA | MYSC | Boraginaceae |
| crimson fountaingrass | Pennisetum setaceum (Forssk.) Chiov. | PESSA | PESE3 | Poaceae |
| common four o'clock | Mirabilis jalapa L. | MIBJA | MIJA | Nyctaginaceae |
| hairy four o'clock | Mirabilis hirsuta (Pursh) MacMill. | MIBHI | MIHI | Nyctaginaceae |
| wild four o'clock | Mirabilis nyctaginea (Michx.) Macmill. | MIBNY | MINY | Nyctaginaceae |
| foxglove | Digitalis purpurea L. | DIKPU | DIPU | Plantaginaceae |
| bristly foxtail | Setaria verticillata (L.) Beauv. | SETVE | SEVE3 | Poaceae |
| Carolina foxtail | Alopecurus carolinianus Walt. | ALOCA | ALCA4 | Poaceae |
| creeping meadow foxtail | Alopecurus arundinaceus Poir. | ALOAR | ALAR | Poaceae |
| giant foxtail | Setaria faberi Herrm. | SETFA | SEFA | Poaceae |
| giant green foxtail | Setaria viridis (L.) P. Beauv. var. major (Gaudin) Pospichal | SETVM | SEVIM | Poaceae |
| green foxtail | Setaria viridis (L.) P. Beauv. | SETVI | SEVI4 | Poaceae |
| knotroot foxtail | Setaria parviflora (Poir.) Kerguélen | SETGE | SEPA10 | Poaceae |
| meadow foxtail | Alopecurus pratensis L. | ALOPR | ALPR3 | Poaceae |
| Rendle's foxtail | Alopecurus rendlei Eig. | ALORE | ALRE3 | Poaceae |
| water foxtail | Alopecurus geniculatus L. | ALOGE | ALGE2 | Poaceae |
| West Indian foxtail | Andropogon bicornis L. | ANOBI | ANBI | Poaceae |
| yellow foxtail | Setaria pumila (Poir.) Roem. & Schult. | SETPU | SEPU8 | Poaceae |
| annual fringe rush | Fimbristylis annua (All.) Roem. & Schult. | FIMAN | FIAN | Cyperaceae |
| forked fringe rush | Fimbristylis dichotoma (L.) Vahl | FIMDI | FIDI | Cyperaceae |
| globe fringe rush | Fimbristylis littoralis Gaudich. | FIMLI | FILI3 | Cyperaceae |
| slender fringe rush | Fimbristylis autumnalis (L.) Roem. & Schult. | FIMAU | FIAU2 | Cyperaceae |
| American frogbit | Limnobium spongia (Bosc) Rich. ex Steud. | LIMSP | LISP2 | Hydrocharitaceae |
| European frogbit | Hydrocharis morsus-ranae L. | HYHMR | HYMO6 | Hydrocharitaceae |
| rush fuirena | Fuirena scirpoidea Michx. | FUISC | FUSC | Cyperaceae |
| fumitory | Fumaria officinalis L. | FUMOF | FUOF | Papaveraceae |
| fineleaf fumitory | Fumaria parviflora Lam. | FUMPA | FUPA | Papaveraceae |
| white ramping fumitory | Fumaria capreolata L. | FUMCA | FUCA | Papaveraceae |
| rosering gaillardia | Gaillardia pulchella Foug. | GAIPU | GAPU | Asteraceae |
| green galenia | Galenia pubescens (Eckl. & Zeyh.) Druce | GAJPU | GAPU80 | Aizoaceae |
| hairy galinsoga | Galinsoga quadriradiata Cav. | GASCI | GAQU | Asteraceae |
| smallflower galinsoga | Galinsoga parviflora Cav. | GASPA | GAPA2 | Asteraceae |
| gall of the earth | Prenanthes trifoliolata (Cass.) Fernald | PNNTR | PRTR | Asteraceae |
| eastern gamagrass | Tripsacum dactyloides (L.) L. | TRWDA | TRDA3 | Poaceae |
| Kahila garland lily | Hedychium gardnerianum Sheppard ex Ker Gawl. | HEYGA | HEGA | Zingiberaceae |
| wild garlic | Allium vineale L. | ALLVI | ALVI | Amaryllidaceae |
| biennial gaura | Oenothera gaura W. L. Wagner & Hoch | GAABI | OEGA | Onagraceae |
| Drummond's gaura | Oenothera xenogaura W. L. Wagner & Hoch | GAADR | OEXE | Onagraceae |
| hairy gaura | Oenothera cinerea (Wooton & Standl.) W. L. Wagner & Hoch | GAAVI | OECI | Onagraceae |
| scarlet gaura | Oenothera suffrutescens (Ser.) W. L. Wagner & Hoch | GAACO | OESU3 | Onagraceae |
| wavyleaf gaura | Oenothera sinuosa W. L. Wagner & Hoch | GAASI | OESI3 | Onagraceae |
| dotted gayfeather | Liatris punctata Hook. | LTSPU | LIPU | Asteraceae |
| Carolina geranium | Geranium carolinianum L. | GERCA | GECA5 | Geraniaceae |
| cutleaf geranium | Geranium dissectum L. | GERDI | GEDI | Geraniaceae |
| dovefoot geranium | Geranium molle L. | GERMO | GEMO | Geraniaceae |
| meadow geranium | Geranium pratense L. | GERPR | GEPR4 | Geraniaceae |
| New Zealand geranium | Geranium retrorsum L’Hér. ex DC. | GERRE | GERE | Geraniaceae |
| shiny geranium | Geranium lucidum L. | GERLU | GELU | Geraniaceae |
| smallflower geranium | Geranium pusillum L. | GERPU | GEPU2 | Geraniaceae |
| spotted geranium | Geranium maculatum L. | GERMA | GEMA | Geraniaceae |
| American germander | Teucrium canadense L. | TEUCA | TECA3 | Lamiaceae |
| cutleaf germander | Teucrium botrys L. | TEUBO | TEBO | Lamiaceae |
| gianthyssop | Agastache foeniculum (Pursh) Kuntze | AJTFO | AGFO | Lamiaceae |
| catnip gianthyssop | Agastache nepetoides (L.) Kuntze | AJTNE | AGNE2 | Lamiaceae |
| bluehead gilia | Gilia capitata Sims | GIICA | GICA5 | Polemoniaceae |
| broadleaf glandweed | Parentucellia latifolia (L.) Caruel | PATLA | PALA28 | Orobanchaceae |
| yellow glandweed | Parentucellia viscosa (L.) Caruel | PATVI | PAVI3 | Orobanchaceae |
| glasswort | Salsola soda L. | SASSO | SASO3 | Chenopodiaceae |
| narrowleaf globemallow | Sphaeralcea angustifolia (Cav.) G. Don | SPHAN | SPAN3 | Malvaceae |
| scarlet globemallow | Sphaeralcea coccinea (Nutt.) Rydb. | SPHCO | SPCO | Malvaceae |
| great globethistle | Echinops sphaerocephalus L. | ECPSP | ECSP | Asteraceae |
| globifera | Micranthemum umbrosum (J. F. Gmel.) S. F. Blake | MJCUM | MIUM | Linderniaceae |
| barb goatgrass | Aegilops triuncialis L. | AEGTR | AETR | Poaceae |
| jointed goatgrass | Aegilops cylindrica Host | AEGCY | AECY | Poaceae |
| ovate goatgrass | Aegilops geniculata Roth | AEGGE | AEGE | Poaceae |
| goatsrue | Galega officinalis L. | GAGOF | GAOF | Fabaceae |
| goldenclub | Orontium aquaticum L. | ORUAQ | ORAQ | Araceae |
| longleaf false goldeneye | Heliomeris longifolia (B. L. Rob. & Greenm.) Cockerell | VIUAN | HELO6 | Asteraceae |
| longleaf false goldeneye | Heliomeris longifolia (B. L. Rob. & Greenm.) Cockerell var. annua (M. E. Jones) W. F. Yates | VIUAN | HELOA2 | Asteraceae |
| California goldenrod | Solidago velutina DC. ssp. californica ( Nutt.) Semple | SOOCF | SOCA5 | Asteraceae |
| Canada goldenrod | Solidago canadensis L. | SOOCA | SOCA6 | Asteraceae |
| giant goldenrod | Solidago gigantea Aiton | SOOGI | SOGI | Asteraceae |
| gray goldenrod | Solidago nemoralis Aiton | SOONE | SONE | Asteraceae |
| hollow goldenrod | Solidago fistulosa Mill. | SOOFI | SOFI | Asteraceae |
| Missouri goldenrod | Solidago missouriensis Nutt. | SOOMS | SOMI2 | Asteraceae |
| narrowleaf goldenrod | Euthamia graminifolia (L.) Nutt. | ETIGR | EUGR5 | Asteraceae |
| rigid goldenrod | Solidago rigida L. | SOORI | SORI2 | Asteraceae |
| rough goldenrod | Solidago rugosa Mill. | SOORU | SORU2 | Asteraceae |
| seaside goldenrod | Solidago sempervirens L. | SOOSE | SOSE | Asteraceae |
| tall goldenrod | Solidago altissima L. | SOOAL | SOAL6 | Asteraceae |
| western goldenrod | Euthamia occidentalis Nutt. | ETIOC | EUOC4 | Asteraceae |
| goldentop | Lamarckia aurea (L.) Moench | LAAAU | LAAU | Poaceae |
| narrowleaf goldentop | Euthamia caroliniana (L.) Green ex Porter & Britton | ETITE | EUCA26 | Asteraceae |
| goldenweed | Grindelia ciliata (Nutt.) Spreng. | GRNCI | GRCI4 | Asteraceae |
| goldenweed | Grindelia papposa G. L. Nesom & Y. B. Suh | GRNCI | GRPA8 | Asteraceae |
| common goldenweed | Isocoma coronopifolia (A. Gray) Greene | IOCCO | ISCO | Asteraceae |
| Drummond goldenweed | Isocoma drummondii (Torr. & A. Gray) Greene | HAPDR | ISDR | Asteraceae |
| hairystem gooseberry | Ribes hirtellum Michx. | RIBHI | RIHI | Grossulariaceae |
| pasture gooseberry | Ribes cynosbati L. | RIBCY | RICY | Grossulariaceae |
| spreading gooseberry | Ribes divaricatum Douglas | RIBDV | RIDI | Grossulariaceae |
| whitestem gooseberry | Ribes inerme Rydb. | RIBIN | RIIN2 | Grossulariaceae |
| blite goosefoot | Chenopodium capitatum (L.) Ambrosi | CHECA | CHCA4 | Chenopodiaceae |
| city goosefoot | Chenopodium urbicum L. | CHEUR | CHUR | Chenopodiaceae |
| clammy goosefoot | Dysphania pumilio (R. Br.) Mosyakin & Clemants | CHEPU | DYPU | Chenopodiaceae |
| cutleaf goosefoot | Dysphania multifida (L.) Mosyakin & Clemants | CHEMF | DYMU | Chenopodiaceae |
| figleaf goosefoot | Chenopodium ficifolium Sm. | CHEFI | CHFI4 | Chenopodiaceae |
| giantseed goosefoot | Chenopodium simplex (Torr.) Raf. | CHEHG | CHSI2 | Chenopodiaceae |
| Jerusalem oak goosefoot | Dysphania botrys (L.) Mosyakin & Clemants | CHEBO | DYBO | Chenopodiaceae |
| lateflower goosefoot | Chenopodium album L. var. striatum Krašan | CHESG | CHALS2 | Chenopodiaceae |
| manyseed goosefoot | Chenopodium polyspermum L. | CHEPO | CHPO | Chenopodiaceae |
| mealy goosefoot | Chenopodium incanum (S. Watson) A. Heller | CHEIN | CHIN2 | Chenopodiaceae |
| Missouri goosefoot | Chenopodium album L. var. missouriense (Aellen) I. J. Bassett & C. W. Crompton | CHEMI | CHALM2 | Chenopodiaceae |
| nettleleaf goosefoot | Chenopodium murale L. | CHEMU | CHMU2 | Chenopodiaceae |
| oakleaf goosefoot | Chenopodium glaucum L. | CHEGL | CHGL3 | Chenopodiaceae |
| perennial goosefoot | Chenopodium bonus-henricus L. | CHEBH | CHBO | Chenopodiaceae |
| red goosefoot | Chenopodium rubrum L. | CHERU | CHRU | Chenopodiaceae |
| Rocky Mountain goosefoot | Chenopodium salinum Standl. | CHESA | CHSA2 | Chenopodiaceae |
| goosegrass | Eleusine indica (L.) Gaertn. | ELEIN | ELIN3 | Poaceae |
| threespike goosegrass | Eleusine tristachya (Lam.) Lam. | ELETR | ELTR2 | Poaceae |
| gooseweed | Sphenoclea zeylanica Gaertn. | SPDZE | SPZE | Sphenocleaceae |
| gorse | Ulex europaeus L. | ULEEU | ULEU | Fabaceae |
| buffalo gourd | Cucurbita foetidissima Kunth | CUUFO | CUFO | Cucurbitaceae |
| fingerleaf gourd | Cucurbita digitata Gray | CUUDI | CUDI | Cucurbitaceae |
| ivy gourd | Coccinia grandis (L.) J. Voigt | COCGR | COGR9 | Cucurbitaceae |
| Texas gourd | Cucurbita pepo L. var. texana (Scheele) D. Decker | CUUTX | CUPET | Cucurbitaceae |
| wild spiny gourd | Cucumis dipsaceus Ehrenb. ex Spach | CUMDI | CUDI2 | Cucurbitaceae |
| bishops goutweed | Aegopodium podagraria L. | AEOPO | AEPO | Apiaceae |
| sixweeks grama | Bouteloua barbata Lag. | BOBBA | BOBA2 | Poaceae |
| sixweeks needle grama | Bouteloua aristidoides (Kunth) Griseb. | BOBAR | BOAR | Poaceae |
| fox grape | Vitis labrusca L. | VITLA | VILA8 | Vitaceae |
| frost grape | Vitis vulpina L. | VITVU | VIVU | Vitaceae |
| mountain grape | Berberis aquifolium Pursh | MAHAQ | BEAQ | Berberidaceae |
| mustang grape | Vitis mustangensis Buckley | VITCA | VIMU2 | Vitaceae |
| Oregon grape | Berberis nervosa Pursh | MAHNE | BENE2 | Berberidaceae |
| possum grape | Cissus verticillata (L.) Nicolson & C. E. Jarvis | CIBSI | CIVE3 | Vitaceae |
| riverbank grape | Vitis riparia Michx. | VITVU | VIRI | Vitaceae |
| summer grape | Vitis aestivalis Michx. | VITAE | VIAE | Vitaceae |
| grape hyacinth | Muscari botryoides (L.) Mill. | MUSBO | MUBO | Asparagaceae |
| Capetown grass | Tribolium obliterum (Hemsl.) Renvoize | TROB6 | Poaceae | |
| greasewood | Sarcobatus vermiculatus (Hook.) Torr. | SAYVE | SAVE4 | Sarcobataceae |
| California greenbriar | Smilax californica (A. DC.) A. Gray | SMICF | SMCA2 | Smilacaceae |
| coral greenbriar | Smilax walteri Pursh | SMIWA | SMWA | Smilacaceae |
| lanceleaf greenbriar | Smilax smallii Morong | SMISM | SMSM | Smilacaceae |
| roundleaf greenbriar | Smilax rotundifolia L. | SMIRO | SMRO | Smilacaceae |
| green molly | Neokochia americana (S. Watson) G. L. Chu & S. C. Sand. | KCHAM | NEAM | Chenopodiaceae |
| stiff greenthread | Thelesperma filifolium (Hook.) A. Gray | TLSFI | THFI | Asteraceae |
| Dyer greenweed | Genista tinctoria L. | GENTI | GETI | Fabaceae |
| corn gromwell | Buglossoides arvensis (L.) I. M. Johnston | LITAR | BUAR3 | Boraginaceae |
| pearl gromwell | Lithospermum officinale L. | LITOF | LIOF | Boraginaceae |
| western gromwell | Lithospermum ruderale Dougl. ex Lehm. | LITRU | LIRU4 | Boraginaceae |
| clammy groundcherry | Physalis heterophylla Nees | PHYHE | PHHE5 | Solanaceae |
| cutleaf groundcherry | Physalis angulata L. | PHYAN | PHAN5 | Solanaceae |
| downy groundcherry | Physalis pubescens L. | PHYPU | PHPU7 | Solanaceae |
| dwarf groundcherry | Chamaesaracha coronopus (Dunal) A. Gray | CHFCO | CHCO2 | Solanaceae |
| grape groundcherry | Physalis viscosa L. | PHYVI | PHVI17 | Solanaceae |
| longleaf groundcherry | Physalis longifolia Nutt. var. longifolia | PHYLF | PHLOL3 | Solanaceae |
| purple groundcherry | Quincula lobata (Torr.) Raf. | PHYLO | QULO2 | Solanaceae |
| smooth groundcherry | Physalis longifolia Nutt. var. subglabrata (Mack. & Bush) Cronquist | PHYSU | PHLOS | Solanaceae |
| tomatillo groundcherry | Physalis philadelphica Lam. | PHYIX | PHPH2 | Solanaceae |
| Virginia groundcherry | Physalis virginiana Mill. | PHVI5 | Solanaceae | |
| Wright groundcherry | Physalis acutifolia (Miers) Sandw. | PHYWR | PHAC6 | Solanaceae |
| balsam groundsel | Packera paupercula (Michx.) Á. Löve & D. Löve | SENPU | PAPA20 | Asteraceae |
| common groundsel | Senecio vulgaris L. | SENVU | SEVU | Asteraceae |
| cressleaf groundsel | Packera glabella (Poir.) C. Jeffrey | SENGL | PAGL17 | Asteraceae |
| fireweed groundsel | Senecio linearifolius A. Rich. | SENLI | SELI | Asteraceae |
| prairie groundsel | Packera plattensis (Nutt.) W.A. Weber & A. Löve | SENPN | PAPL12 | Asteraceae |
| Riddell groundsel | Senecio riddellii Torr. & A. Gray | SENRI | SERI2 | Asteraceae |
| Small's groundsel | Packera anonyma (Alph. Wood) W. A. Weber & Á. Löve | SENAA | PAAN6 | Asteraceae |
| sticky groundsel | Senecio viscosus L. | SENVI | SEVI2 | Asteraceae |
| threadleaf groundsel | Senecio flaccidus Less. | SENFC | SEFL3 | Asteraceae |
| woodland groundsel | Senecio sylvaticus L. | SENSI | SESY | Asteraceae |
| guajillo | Senegalia berlandieri (Benth.) Britton & Rose | ACABE | SEBE2 | Fabaceae |
| guava | Psidium guajava L. | PSIGU | PSGU | Myrtaceae |
| strawberry guava | Psidium cattleyanum Sabine | PSICA | PSCA | Myrtaceae |
| guayacan | Guaiacum angustifolium Engelm. | POKAN | GUAN | Zygophyllaceae |
| guineagrass | Megathyrsus maximus (Jacq.) B. K. Simon & S. W. L. Jacobs | PANMA | MEMA22 | Poaceae |
| common gumplant | Grindelia camporum Greene | GRNCA | GRCA | Asteraceae |
| curlycup gumweed | Grindelia squarrosa (Pursh) Dunal | GRNSQ | GRSQ | Asteraceae |
| low gumweed | Grindelia nana Nutt. | GRNNA | GRNA | Asteraceae |
| crinkled hairgrass | Deschampsia flexuosa (L.) Trin. | DECFL | DEFL | Poaceae |
| silver hairgrass | Aira caryophyllea L. | AIRCA | AICA | Poaceae |
| slender hairgrass | Deschampsia elongata (Hook.) Munro | DECEL | DEEL | Poaceae |
| halogeton | Halogeton glomeratus (M. Bieb.) Ledeb. | HALGL | HAGL | Chenopodiaceae |
| hardgrass | Sclerochloa dura (L.) Beauv. | SCMDU | SCDU2 | Poaceae |
| hardhack | Spiraea tomentosa L. | SPVTO | SPTO2 | Rosaceae |
| Harding grass | Phalaris aquatica L. | PHATU | PHAQ | Poaceae |
| harebell | Campanula rotundifolia L. | CMPRO | CARO2 | Campanulaceae |
| harvestlice | Agrimonia parviflora Aiton | AGIPA | AGPA6 | Rosaceae |
| fall hawkbit | Scorzoneroides autumnalis (L.) Moench | LEBAU | SCAU8 | Asteraceae |
| lesser hawkbit | Leontodon saxatilis Lam. | LEBNT | LESA24 | Asteraceae |
| rough hawkbit | Leontodon nudicaulis (L.) Banks ex Schinz & R. Keller | LEBNT | LENU2 | Asteraceae |
| Asiatic hawksbeard | Youngia japonica (L.) DC. | UOUJA | YOJA | Asteraceae |
| bristly hawksbeard | Crepis setosa Haller f. | CVPSE | CRSE2 | Asteraceae |
| European hawksbeard | Crepis vesicaria L. | CVPVV | CRVE3 | Asteraceae |
| narrowleaf hawksbeard | Crepis tectorum L. | CVPTE | CRTE3 | Asteraceae |
| rough hawksbeard | Crepis biennis L. | CVPBI | CRBI3 | Asteraceae |
| smooth hawksbeard | Crepis capillaris (L.) Wallr. | CVPCA | CRCA3 | Asteraceae |
| western hawksbeard | Crepis occidentalis Nutt. | CVPOC | CROC | Asteraceae |
| common hawkweed | Hieracium lachenalii Suter | HIELA | HILA8 | Asteraceae |
| queendevil hawkweed | Hieracium gronovii L. | HIEGR | HIGR3 | Asteraceae |
| kingdevil hawkweed | Hieracium piloselloides Vill. | HIEPO | HIPI2 | Asteraceae |
| meadow hawkweed | Hieracium caespitosum Dumort. | HIECA | HICA10 | Asteraceae |
| mouseear hawkweed | Hieracium pilosella L. | HIEPI | HIPI | Asteraceae |
| narrowleaf hawkweed | Hieracium umbellatum L. | HIEUM | HIUM | Asteraceae |
| orange hawkweed | Hieracium aurantiacum L. | HIEAU | HIAU | Asteraceae |
| polar hawkweed | Hieracium atratum Fr. | HIEAT | HIAT2 | Asteraceae |
| smooth hawkweed | Hieracium laevigatum Willd. | HIELV | HILA4 | Asteraceae |
| tall hawkweed | Hieracium praealtum Vill. ex Gochnat | HIEPR | HIPR3 | Asteraceae |
| yellowdevil hawkweed | Hieracium x floribundum Wimmer & Grab. (pro sp.) [caespitosum x lactucella] | HIEFL | HIFL3 | Asteraceae |
| black hawthorn | Crataegus douglasii Lindl. | CSCDO | CRDO2 | Rosaceae |
| cockspur hawthorn | Crataegus crus-galli L. | CSCCG | CRCR2 | Rosaceae |
| English hawthorn | Crataegus monogyna Jacq. | CSCMO | CRMO3 | Rosaceae |
| fleshy hawthorn | Crataegus succulenta Schrad. ex Link | CSCSC | CRSU5 | Rosaceae |
| parsley hawthorn | Crataegus marshallii Eggl. | CSCMS | CRMA5 | Rosaceae |
| pasture hawthorn | Crataegus spathulata Michx. | CSCSP | CRSP | Rosaceae |
| river hawthorn | Crataegus rivularis Nutt. | CSCRV | CRRI | Rosaceae |
| hazelnut | Corylus cornuta Marsh | CYLCR | COCO6 | Betulaceae |
| healall | Prunella vulgaris L. | PRUVU | PRVU | Lamiaceae |
| hedgeparsley | Torilis arvensis (Huds.) Link | TOIAR | TOAR | Apiaceae |
| Japanese hedgeparsley | Torilis japonica (Houtt.) DC. | TOIJA | TOJA | Apiaceae |
| knotted hedgeparsley | Torilis nodosa (L.) Gaertn. | TOINO | TONO | Apiaceae |
| alkali heliotrope | Heliotropium curassavicum L. var. oculatum (A. Heller) I. M. Johnst. ex Tidestr. | HEOCC | HECUO | Boraginaceae |
| clasping heliotrope | Heliotropium amplexicaule Vahl | HEOAM | HEAM4 | Boraginaceae |
| European heliotrope | Heliotropium europaeum L. | HEOEU | HEEU | Boraginaceae |
| Indian heliotrope | Heliotropium indicum L. | HEOIN | HEIN | Boraginaceae |
| seaside heliotrope | Heliotropium curassavicum L. | HEOCU | HECU3 | Boraginaceae |
| spatulateleaf heliotrope | Heliotropium curassavicum L. var. obovatum DC. | HEOCB | HECUO2 | Boraginaceae |
| helleborine | Epipactis helleborine (L.) Crantz | EPPHE | EPHE | Orchidaceae |
| hemianthus | Micranthemum glomeratum (Chapm.) Shinners | MJCGL | MIGL6 | Linderniaceae |
| common hempnettle | Galeopsis tetrahit L. | GAETE | GATE2 | Lamiaceae |
| red hempnettle | Galeopsis ladanum L. | GAELA | GALA | Lamiaceae |
| climbing hempweed | Mikania scandens (L.) Willd. | MIKSC | MISC | Asteraceae |
| hairy hempweed | Mikania cordifolia (L. f.) Willd. | MIKCF | MICO9 | Asteraceae |
| hen and chickens | Sempervivum tectorum L. | SEPTE | SETE5 | Crassulaceae |
| black henbane | Hyoscyamus niger L. | HSYNI | HYNI | Solanaceae |
| henbit | Lamium amplexicaule L. | LAMAM | LAAM | Lamiaceae |
| hens eyes | Ardisia crenata Sims | ADACN | ARCR80 | Primulaceae |
| herb robert | Geranium robertianum L. | GERRO | GERO | Geraniaceae |
| gray herniaria | Herniaria hirsuta L. ssp. cinerea (DC.) Coutinho | HEQCN | HEHIC | Caryophyllaceae |
| sea hibiscus | Hibiscus tiliaceus L. | HIBTI | HITI | Malvaceae |
| pignut hickory | Carya glabra (Mill.) Sweet | CYAGL | CAGL8 | Juglandaceae |
| hippograss | Vossia cuspidata (Roxb.) Griff. | VOSCU | VOCU | Poaceae |
| hogpotato | Hoffmannseggia glauca (Ortega) Eifert | HOFDE | HOGL2 | Fabaceae |
| giant hogweed | Heracleum mantegazzianum Sommier & Levier | HERMZ | HEMA17 | Apiaceae |
| English holly | Ilex aquifolium L. | ILEAQ | ILAQ80 | Aquifoliaceae |
| hollyhock | Alcea rosea L. | ALGRO | ALRO3 | Malvaceae |
| Amur honeysuckle | Lonicera maackii (Rupr.) Herder | LONMA | LOMA6 | Caprifoliaceae |
| Bell honeysuckle | Lonicera x bella Zabel | LONBE | LOBE | Caprifoliaceae |
| bush honeysuckle | Diervilla lonicera Mill. | DIVLO | DILO | Caprifoliaceae |
| fly honeysuckle | Lonicera xylosteum L. | LONXY | LOXY | Caprifoliaceae |
| Japanese honeysuckle | Lonicera japonica Thunb. | LONJA | LOJA | Caprifoliaceae |
| Morrow honeysuckle | Lonicera morrowii A. Gray | LONMO | LOMO2 | Caprifoliaceae |
| Standish honeysuckle | Lonicera standishii Jacques | LONST | LOST2 | Caprifoliaceae |
| sweetberry honeysuckle | Lonicera caerulea L. | LONCO | LOCA6 | Caprifoliaceae |
| Tatarian honeysuckle | Lonicera tatarica L. | LONTA | LOTA | Caprifoliaceae |
| trumpet honeysuckle | Lonicera sempervirens L. | LONSE | LOSE | Caprifoliaceae |
| Japanese hop | Humulus japonicus Siebold & Zucc. | HUMJA | HUJA | Cannabaceae |
| hoptree | Ptelea trifoliata L. | PTATR | PTTR | Rutaceae |
| white horehound | Marrubium vulgare L. | MAQVU | MAVU | Lamiaceae |
| spineless hornwort | Ceratophyllum echinatum A. Gray | CEYEC | CEEC2 | Ceratophyllaceae |
| littleleaf horsebrush | Tetradymia glabrata Torr. & A. Gray | TEYGL | TEGL | Asteraceae |
| spineless horsebrush | Tetradymia canescens DC. | TEYCA | TECA2 | Asteraceae |
| Carolina horsenettle | Solanum carolinense L. | SOLCA | SOCA3 | Solanaceae |
| robust horsenettle | Solanum dimidiatum Raf. | SOLDM | SODI | Solanaceae |
| horseradish | Armoracia rusticana G. Gaertn., B. Mey. & Scherb. | ARWLA | ARRU4 | Brassicaceae |
| field horsetail | Equisetum arvense L. | EQUAR | EQAR | Equisetaceae |
| giant horsetail | Equisetum telmateia Ehrh. | EQUTE | EQTE | Equisetaceae |
| marsh horsetail | Equisetum palustre L. | EQUPA | EQPA | Equisetaceae |
| sylvan horsetail | Equisetum sylvaticum L. | EQUSY | EQSY | Equisetaceae |
| water horsetail | Equisetum fluviatile L. | EQUFL | EQFL | Equisetaceae |
| horseweed | Erigeron canadensis L. | ERICA | ERCA20 | Asteraceae |
| sprawling horseweed | Calyptocarpus vialis Less. | BLATA | CAVI2 | Asteraceae |
| houndstongue | Cynoglossum officinale L. | CYWOF | CYOF | Boraginaceae |
| black huckleberry | Gaylussacia baccata (Wangenh.) K. Koch | GAYBA | GABA | Ericaceae |
| California huckleberry | Vaccinium ovatum Pursh | VACOV | VAOV2 | Ericaceae |
| red huckleberry | Vaccinium parviflorum Sm. | VACPV | VAPA | Ericaceae |
| hydrilla | Hydrilla verticillata (L. f.) Royle | HYLLI | HYVE3 | Hydrocharitaceae |
| oneflower hydrolea | Hydrolea uniflora Raf. | HYMUN | HYUN | Hydroleaceae |
| smooth hydrolea | Hydrolea glabra Schumach. | HYMGL | Hydroleaceae | |
| Indian hygrophila | Hygrophila polysperma (Roxb.) T. Anderson | HYGPO | HYPO3 | Acanthaceae |
| lake hygrophila | Hygrophila lacustris (Schltdl. & Cham.) Nees | HYGLC | HYLA | Acanthaceae |
| whitebract hymenopappus | Hymenopappus scabiosaeus L'Hér. | HYYSB | HYSC | Asteraceae |
| Canary Island St. Johnswort | Hypericum canariense L. | HYPCN | HYCA11 | Hypericaceae |
| comb hyptis | Mesosphaerum pectinatum (L.) Kuntze | HPYPE | MEPE | Lamiaceae |
| hyssop | Hyssopus officinalis L. | HYSOF | HYOF | Lamiaceae |
| crystalline iceplant | Mesembryanthemum crystallinum L. | MEKCR | MECR3 | Aizoaceae |
| roundleaf iceplant | Conicosia pugioniformis (L.) N.E. Br. | KSAPU | COPU18 | Aizoaceae |
| slenderleaf iceplant | Mesembryanthemum nodiflorum L. | MEKNO | MENO2 | Aizoaceae |
| exserted Indian paintbrush | Castilleja exserta (A. Heller) T. I. Chuang & Heckard | CSLEX | CAEX14 | Orobanchaceae |
| yellow Indiangrass | Sorghastrum nutans (L.) Nash | SOSNU | SONU2 | Poaceae |
| pale Indian plantain | Arnoglossum atriplicifolium (L.) H. Rob. | CACAT | ARAT | Asteraceae |
| Indiantobacco | Lobelia inflata L. | LOBIN | LOIN | Campanulaceae |
| blanket indigo | Indigofera pilosa Poir. | INDPI | INPI | Fabaceae |
| creeping indigo | Indigofera spicata Forssk. | INDSP | INSP2 | Fabaceae |
| hairy indigo | Indigofera hirsuta L. | INDHI | INHI | Fabaceae |
| indigobush | Amorpha fruticosa L. | AMHFR | AMFR | Fabaceae |
| intermediate lady's-mantle | Alchemilla xanthochlora Rothm. | ALCVU | ALXA | Rosaceae |
| blueflag iris | Iris versicolor L. | IRIVE | IRVE2 | Iridaceae |
| Douglas iris | Iris douglasiana Herb. | IRIDO | IRDO | Iridaceae |
| Virginia blueflag iris | Iris virginica L. | IRIVI | IRVI | Iridaceae |
| western blueflag iris | Iris missouriensis Nutt. | IRIMI | IRMI | Iridaceae |
| yellowflag iris | Iris pseudacorus L. | IRIPS | IRPS | Iridaceae |
| inland ironweed | Vernonia baldwinii Torr. ssp. interior (Small) Faust | VENBI | VEBAI2 | Asteraceae |
| New York ironweed | Vernonia noveboracensis (L.) Michx. | VENNO | VENO | Asteraceae |
| prairie ironweed | Vernonia fasciculata Michx. | VENFS | VEFA2 | Asteraceae |
| tall ironweed | Vernonia gigantea (Walter) Trel. | VENGI | VEGI | Asteraceae |
| western ironweed | Vernonia baldwinii Torr. | VENBA | VEBA | Asteraceae |
| itchgrass | Rottboellia cochinchinensis (Lour.) Clayton | ROOEX | ROCO6 | Poaceae |
| Algerian ivy | Hedera canariensis Willd. | HEEHC | HECA37 | Araliaceae |
| Atlantic ivy | Hedera hibernica (G. Kirchn.) Bean | HEEHI | HEHI12 | Araliaceae |
| cape ivy | Delairea odorata Lem. | SENMI | DEOD | Asteraceae |
| English ivy | Hedera helix L. | HEEHE | HEHE | Araliaceae |
| ground ivy | Glechoma hederacea L. | GLEHE | GLHE2 | Lamiaceae |
| Kenilworth ivy | Cymbalaria muralis G. Gaertn., B. Mey. & Scherb. | CBYMU | CYMU | Plantaginaceae |
| threecorner jack | Emex australis Steinh. | EMEAU | EMAU | Polygonaceae |
| blue Jacob's ladder | Polemonium caeruleum L. | PMNCO | POCA2 | Polemoniaceae |
| jaraguagrass | Hyparrhenia rufa (Nees) Stapf | HYRRU | HYRU2 | Poaceae |
| jazmin de rio | Cleome viscosa L. | CLEVI | CLVI9 | Cleomaceae |
| Jerusalem cherry | Solanum pseudocapsicum L. | SOLPC | SOPS | Solanaceae |
| day jessamine | Cestrum diurnum L. | CEMDI | CEDI6 | Solanaceae |
| jetbead | Rhodotypos scandens (Thunb.) Makino | RHQSC | RHSC3 | Rosaceae |
| jewelweed | Impatiens capensis Meerb. | IPACA | IMCA | Balsaminaceae |
| smallflower jewelweed | Impatiens parviflora DC. | IPAPA | IMPA2 | Balsaminaceae |
| jute | Corchorus aestuans L. | CRGAE | COAE | Malvaceae |
| shrine jimmyweed | Isocoma tenuisecta Greene | HAPTE | ISTE2 | Asteraceae |
| southern jimmyweed | Isocoma pluriflora (Torr. & A. Gray) Greene | HAPHE | ISPL | Asteraceae |
| jimsonweed | Datura stramonium L. | DATST | DAST | Solanaceae |
| spotted joe pye weed | Eutrochium maculatum (L.) E. E. Lamont | EUPML | EUMA9 | Asteraceae |
| sweet joe pye weed | Eutrochium purpureum (L.) E. E. Lamont | EUPPU | EUPU21 | Asteraceae |
| johnsongrass | Sorghum halepense (L.) Pers. | SORHA | SOHA | Poaceae |
| rough jointgrass | Aeschynomene rudis Benth. | AESRU | AERU | Fabaceae |
| American jointvetch | Aeschynomene americana L. | AESAM | AEAM | Fabaceae |
| Indian jointvetch | Aeschynomene indica L. | AESIN | AEIN | Fabaceae |
| northern jointvetch | Aeschynomene virginica (L.) Britton, Sterns & Poggenb. | AESVI | AEVI3 | Fabaceae |
| sessile joyweed | Alternanthera sessilis (L.) R. Br. ex DC. | ALRSE | ALSE4 | Amaranthaceae |
| jubatagrass | Cortaderia jubata (Lemoine ex Carrière) Stapf | CDTJU | COJU2 | Poaceae |
| junglerice | Echinochloa colona (L.) Link | ECHCO | ECCO2 | Poaceae |
| Ashe juniper | Juniperus ashei J. Buchholz | IUPAS | JUAS | Cupressaceae |
| common juniper | Juniperus communis L. | IUPCO | JUCO6 | Cupressaceae |
| redberry juniper | Juniperus pinchotii Sudw. | IUPPI | JUPI | Cupressaceae |
| Utah juniper | Juniperus osteosperma (Torr.) Little | IUPOS | JUOS | Cupressaceae |
| western juniper | Juniperus occidentalis Hook. | IUPOC | JUOCO | Cupressaceae |
| kahiliflower | Grevillea banksii R. Br. | GREBA | GRBA | Proteaceae |
| kangaroothorn | Acacia paradoxa DC. | ACAAR | ACPA8 | Fabaceae |
| khakiweed | Alternanthera pungens Kunth | ALRRE | ALPU3 | Amaranthaceae |
| kiawe | Prosopis pallida (Humb. & Bonpl. ex Willd.) Kunth | PRCPA | PRPA4 | Fabaceae |
| kikuyugrass | Pennisetum clandestinum Hochst. ex Chiov. | PESCL | PECL2 | Poaceae |
| kleingrass | Panicum coloratum L. | PANCO | PACO2 | Poaceae |
| bighead knapweed | Centaurea macrocephala Puschk. ex Willd. | CENMC | CEMA9 | Asteraceae |
| black knapweed | Centaurea nigra L. | CENNI | CENI2 | Asteraceae |
| brown knapweed | Centaurea jacea L. | CENJA | CEJA | Asteraceae |
| Canary Islands knapweed | Volutaria canariensis Wagenitz | Asteraceae | ||
| diffuse knapweed | Centaurea diffusa Lam. | CENDI | CEDI3 | Asteraceae |
| featherhead knapweed | Centaurea trichocephala Bieb. ex Willd. | CENTC | CETR12 | Asteraceae |
| meadow knapweed | Centaurea x moncktonii C. E. Britton | CEMO6 | Asteraceae | |
| North African knapweed | Centaurea diluta Ait. | CENDL | CEDI4 | Asteraceae |
| Russian knapweed | Rhaponticum repens (L.) Hidalgo | CENRE | ACRE3 | Asteraceae |
| spotted knapweed | Centaurea stoebe L. | CENRH | CEST8 | Asteraceae |
| squarrose knapweed | Centaurea virgata Lam. | CENSQ | CEVI | Asteraceae |
| Vochin knapweed | Centaurea nigrescens Willd. | CENVO | CENI3 | Asteraceae |
| knawel | Scleranthus annuus L. | SCRAN | SCAN2 | Caryophyllaceae |
| knotgrass | Paspalum distichum L. | PASDS | PADI6 | Poaceae |
| blackfringe knotweed | Fallopia cilinodis (Michx.) Holub | POLCI | FACI | Polygonaceae |
| Bohemian knotweed | Reynoutria × bohemica Chrtek & Chrtková | REYBO | REBO | Polygonaceae |
| bushy knotweed | Polygonum ramosissimum Michx. | POLRA | PORA3 | Polygonaceae |
| common knotweed | Polygonum arenastrum Boreau | POLAR | POAR11 | Polygonaceae |
| Douglas knotweed | Polygonum douglasii Greene | POLDO | PODO4 | Polygonaceae |
| erect knotweed | Polygonum erectum L. | POLER | POER2 | Polygonaceae |
| Himalayan knotweed | Koenigia polystachya (Wall. ex Meisn.) T. M. Schust. & Reveal | POLPS | Polygonaceae | |
| Japanese knotweed | Reynoutria japonica Houtt. | POLCU | REJA2 | Polygonaceae |
| prostrate knotweed | Polygonum aviculare L. | POLAV | POAV | Polygonaceae |
| Sakhalin knotweed | Reynoutria sachalinensis (F. Schmidt) Nakai | REYSA | RESA2 | Polygonaceae |
| silversheath knotweed | Polygonum argyrocoleon Steud. ex Kuntze | POLAG | POAR5 | Polygonaceae |
| striate knotweed | Polygonum achoreum Blake | POLAH | POAC3 | Polygonaceae |
| tufted knotweed | Persicaria longiseta (Bruijn) Kitag. | POLBL | PELO10 | Polygonaceae |
| kochia | Bassia scoparia (L.) A. J. Scott | KCHSC | BASC5 | Chenopodiaceae |
| Kosters curse | Clidemia hirta (L.) D.Don | CXAHI | CLHI3 | Melastomataceae |
| kudzu | Pueraria montana (Lour.) Merr. var. lobata (Willd.) Maesen & S.M. Almeida ex Sanjappa & Predeep | PUEMO | PUMOL | Fabaceae |
| tropical kudzu | Pueraria phaseoloides (Roxb.) Benth. | PUEPH | PUPH2 | Fabaceae |
| kyasumagrass | Pennisetum pedicellatum Trin. | PESPE | PEPE24 | Poaceae |
| cockscomb kyllinga | Kyllinga squamulata Thonn. ex Vahl | KYLSQ | KYSQ | Cyperaceae |
| false green kyllinga | Kyllinga gracillima Miq. | KYLGR | KYGR | Cyperaceae |
| fragrant kyllinga | Kyllinga odorata Vahl | CYPSF | KYOD | Cyperaceae |
| green kyllinga | Kyllinga brevifolia Rottb. | KYLBR | KYBR | Cyperaceae |
| tufted kyllinga | Kyllinga pumila Michx. | KYLPU | KYPU | Cyperaceae |
| white kyllinga | Kyllinga nemoralis (J. R. Forst. & G. Forst.) Dandy ex Hutch. & Dalziel | CYPKH | KYNE | Cyperaceae |
| Labrador-tea | Rhododendron groenlandicum (Oeder) Kron & Judd | LEDGR | RHGR3 | Ericaceae |
| lacegrass | Eragrostis capillaris (L.) Nees | ERACP | ERCA | Poaceae |
| northern slender ladys tresses | Spiranthes lacera (Raf.) Raf. | SQTLA | SPLA4 | Orchidaceae |
| lady's-mantle | Alchemilla monticola Opiz | ALCMT | ALMO4 | Rosaceae |
| ladysthumb | Persicaria maculosa Gray | POLPE | PEMA24 | Polygonaceae |
| common lambsquarters | Chenopodium album L. | CHEAL | CHAL7 | Chenopodiaceae |
| narrowleaf lambsquarters | Chenopodium desiccatum A. Nelson | CHEPR | CHDE | Chenopodiaceae |
| netseed lambsquarters | Chenopodium berlandieri Moq. | CHEBE | CHBE4 | Chenopodiaceae |
| slimleaf lambsquarters | Chenopodium leptophyllum (Moq.) Nutt. ex S. Watson | CHELE | CHLE4 | Chenopodiaceae |
| largeleaf lantana | Lantana camara L. | LANCA | LACA2 | Verbenaceae |
| weeping lantana | Lantana montevidensis (Spreng.) Briq. | LANMV | LAMO2 | Verbenaceae |
| Anderson larkspur | Delphinium andersonii A. Gray | DELAN | DEAN | Ranunculaceae |
| Carolina larkspur | Delphinium carolinianum Walt. | DELCA | DECA3 | Ranunculaceae |
| duncecap larkspur | Delphinium x occidentale (S. Watson) S. Watson | DELOC | DEOC | Ranunculaceae |
| dwarf larkspur | Delphinium tricorne Michx. | DELTR | DETR | Ranunculaceae |
| flathead larkspur | Delphinium bicolor Nutt. | DELBI | DEBI | Ranunculaceae |
| Geyer larkspur | Delphinium geyeri Greene | DELGE | DEGE2 | Ranunculaceae |
| low larkspur | Delphinium nuttallianum Pritz. ex Walp. | DELNU | DENU2 | Ranunculaceae |
| Menzies larkspur | Delphinium menziesii DC. | DELME | DEME | Ranunculaceae |
| mountain larkspur | Delphinium glaucum S. Watson | DELGL | DEGL3 | Ranunculaceae |
| tall larkspur | Delphinium barbeyi (Huth) Huth | DELBA | DEBA2 | Ranunculaceae |
| spurge laurel | Daphne laureola L. | DAPLA | DALA11 | Thymelaeaceae |
| Japanese lawngrass | Zoysia japonica Steud. | ZOYJA | ZOJA | Poaceae |
| leadplant | Amorpha canescens Pursh | AMHCN | AMCA6 | Fabaceae |
| white leadtree | Leucaena leucocephala (Lam.) de Wit | LUAGL | LELE10 | Fabaceae |
| three-cornered leek | Allium triquetrum L. | ALLTQ | ALTR4 | Amaryllidaceae |
| Vietnamese lemon mint | Elsholtzia ciliata | ELHCI | ELCI | Lamiaceae |
| lepyrodiclis | Lepyrodiclis holosteoides (C. A. Mey.) Fenzl ex Fisch. & C. A. Mey. | LDCHO | LEHO7 | Caryophyllaceae |
| common lespedeza | Kummerowia striata (Thunb.) Schindl. | LESST | KUST2 | Fabaceae |
| Korean lespedeza | Kummerowia stipulacea (Maxim.) Makino | LESSL | KUST | Fabaceae |
| sericea lespedeza | Lespedeza cuneata (Dum. Cours.) G. Don | LESCU | LECU | Fabaceae |
| Thunberg lespedeza | Lespedeza thunbergii (DC.) Nakai | LESTH | LETH4 | Fabaceae |
| violet lespedeza | Lespedeza violacea (L.) Pers. | LESVI | LEVI6 | Fabaceae |
| biennial lettuce | Lactuca biennis (Moench) Fernald | LACBI | LABI | Asteraceae |
| bitter lettuce | Lactuca virosa L. | LACVI | LAVI8 | Asteraceae |
| blue lettuce | Lactuca tatarica (L.) C. A. Mey. | LACTT | LATA | Asteraceae |
| Florida wild lettuce | Lactuca floridana (L.) Gaertn. | LACFL | LAFL | Asteraceae |
| prickly lettuce | Lactuca serriola L. | LACSE | LASE | Asteraceae |
| tall lettuce | Lactuca canadensis L. | LACCA | LACA | Asteraceae |
| wall lettuce | Mycelis muralis (L.) Dumort. | MYLMU | MYMU | Asteraceae |
| willowleaf lettuce | Lactuca saligna L. | LACSL | LASA | Asteraceae |
| wild licorice | Glycyrrhiza lepidota Pursh | GYCLE | GLLE3 | Fabaceae |
| licoriceplant | Helichrysum petiolare Hilliard & B. L. Burtt | HECPC | HEPE8 | Asteraceae |
| licorice weed | Scoparia dulcis L. | SCFDU | SCDU3 | Plantaginaceae |
| calla lily | Zantedeschia aethiopica (L.) Spreng. | ZNTAE | ZAAE | Araceae |
| swamp lily | Crinum americanum L. | KRMAM | CRAM2 | Amaryllidaceae |
| tiger lily | Lilium lancifolium Thunb. | LILLA | LILA8 | Liliaceae |
| lily of the valley | Convallaria majalis L. | CNKMA | COMA7 | Asparagaceae |
| lily of the valley vine | Salpichroa origanifolia (Lam.) Thell. | SAPOR | SAOR4 | Solanaceae |
| false lily of the valley | Maianthemum canadense Desf. | MNHCA | MACA4 | Asparagaceae |
| limnophila | Limnophila sessiliflora Blume | LIOSE | LISE3 | Plantaginaceae |
| limpograss | Hemarthria altissima (Poir.) Stapf & C. E. Hubb. | HEMAL | HEAL5 | Poaceae |
| lionsear | Leonotis nepetifolia (L.) R. Br. | LEONE | LENE | Lamiaceae |
| mat lippia | Phyla nodiflora (L.) Greene | LIPNO | PHNO2 | Verbenaceae |
| liverseedgrass | Urochloa panicoides P. Beauv. | UROPA | URPA | Poaceae |
| lizardstail | Saururus cernuus L. | SUACE | SACE | Saururaceae |
| bigbend loco | Astragalus mollissimus Torr. var. earlei (Greene ex Rydb.) Tidestr. | ASAEA | ASMOE | Fabaceae |
| blue loco | Astragalus lentiginosus Douglas ex Hook. var. diphysus (A. Gray) M. E. Jones | ASADI | ASLED | Fabaceae |
| halfmoon loco | Astragalus allochrous A. Gray | ASAAL | ASAL6 | Fabaceae |
| horse loco | Astragalus asymmetricus Sheldon | ASAAS | ASAS3 | Fabaceae |
| spotted loco | Astragalus lentiginosus Dougl. ex Hook. | ASALE | ASLE8 | Fabaceae |
| woolly loco | Astragalus mollissimus Torr. | ASAML | ASMO7 | Fabaceae |
| field locoweed | Oxytropis campestris (L.) DC. | OXRCA | OXCA4 | Fabaceae |
| black locust | Robinia pseudoacacia L. | ROBPS | ROPS | Fabaceae |
| honeylocust | Gleditsia triacanthos L. | GLITR | GLTR | Fabaceae |
| California loosestrife | Lythrum californicum Torr. & A. Gray | LYTCA | LYCA4 | Lythraceae |
| dotted loosestrife | Lysimachia punctata L. | LYSPU | LYPU2 | Primulaceae |
| fringed loosestrife | Lysimachia ciliata L. | LYSCI | LYCI | Primulaceae |
| garden loosestrife | Lysimachia vulgaris L. | LYSVU | LYVU | Primulaceae |
| hyssop loosestrife | Lythrum hyssopifolia L. | LYTHY | LYHY2 | Lythraceae |
| purple loosestrife | Lythrum salicaria L. | LYTSA | LYSA2 | Lythraceae |
| spatulaleaf loosestrife | Lythrum portula (L.) D. A. Webb | PPLPO | LYPO4 | Lythraceae |
| swamp loosestrife | Decodon verticillatus (L.) Elliott | DEOVE | DEVE | Lythraceae |
| threebract loosestrife | Lythrum tribracteatum Salzm. ex Spreng. | LYTTR | LYTR2 | Lythraceae |
| wand loosestrife | Lythrum virgatum L. | LYTVI | LYVI3 | Lythraceae |
| winged loosestrife | Lythrum alatum Pursh | LYTAL | LYAL4 | Lythraceae |
| American lotus | Nelumbo lutea Willd. | NELLU | NELU | Nelumbonaceae |
| bahia lovegrass | Eragrostis bahiensis Schrad. ex Schult. | ERABH | ERBA | Poaceae |
| bigtop lovegrass | Eragrostis hirsuta (Michx.) Nees | ERAHI | ERHI | Poaceae |
| coastal lovegrass | Eragrostis refracta (Muhl.) Scribn. | ERARF | ERRE | Poaceae |
| Elliott lovegrass | Eragrostis elliottii S. Watson | ERAEO | EREL | Poaceae |
| feather lovegrass | Eragrostis tenella (L.) P. Beauv. ex Roem. & Schult. | ERAAM | ERTE2 | Poaceae |
| gophertail lovegrass | Eragrostis ciliaris (L.) R. Br. | ERACI | ERCI2 | Poaceae |
| India lovegrass | Eragrostis pilosa (L.) P. Beauv. | ERAPI | ERPI2 | Poaceae |
| Lehmann lovegrass | Eragrostis lehmanniana Nees | ERALE | ERLE | Poaceae |
| little lovegrass | Eragrostis minor Host | ERAPO | ERMI5 | Poaceae |
| Mediterranean lovegrass | Eragrostis barrelieri Daveau | ERABA | ERBA2 | Poaceae |
| Mexican lovegrass | Eragrostis mexicana (Hornem.) Link | ERAMX | ERME | Poaceae |
| purple lovegrass | Eragrostis spectabilis (Pursh) Steud. | ERASP | ERSP | Poaceae |
| red lovegrass | Eragrostis secundiflora J. Presl | ERASF | ERSE | Poaceae |
| tufted lovegrass | Eragrostis pectinacea (Michx.) Nees ex Jedwabn. | ERAPE | ERPE | Poaceae |
| weeping lovegrass | Eragrostis curvula (Schrad.) Nees | ERACU | ERCU2 | Poaceae |
| wall hawkweed | Hieracium murorum L. | HIEMU | HIMU | Asteraceae |
| arctic lupine | Lupinus arcticus S. Watson | LUPAC | LUAR2 | Fabaceae |
| bicolored lupine | Lupinus bicolor Lindl. | LUPBI | LUBI | Fabaceae |
| bush lupine | Lupinus arboreus Sims | LUPAB | LUAR | Fabaceae |
| garden lupine | Lupinus polyphyllus Lindl. | LUPPO | LUPO2 | Fabaceae |
| kings lupine | Lupinus kingii S. Watson | LUPKI | LUKI | Fabaceae |
| low lupine | Lupinus pusillus Pursh | LUPPU | LUPU | Fabaceae |
| perennial lupine | Lupinus perennis L. | LUPPE | LUPE3 | Fabaceae |
| silky lupine | Lupinus sericeus Pursh | LUPSE | LUSE4 | Fabaceae |
| silver lupine | Lupinus argenteus Pursh | LUPAR | LUAR3 | Fabaceae |
| silver lupine | Lupinus argenteus Pursh var. heteranthus (S. Watson) Barneby | LUPCA | LUARH4 | Fabaceae |
| summer lupine | Lupinus formosus Greene | LUPFO | LUFO2 | Fabaceae |
| velvet lupine | Lupinus leucophyllus Douglas ex Lindl. | LUPLE | LULE3 | Fabaceae |
| Wyeth lupine | Lupinus polyphyllus Lindl. var. humicola (A. Nelson) Barneby | LUPHU | LUPOH | Fabaceae |
| Lyon's-grass | Themeda villosa (Poir.) A. Camus | THMVI | THVI2 | Poaceae |
| madder | Rubia tinctorum L. | RBITI | RUTI2 | Rubiaceae |
| field madder | Sherardia arvensis L. | SHRAR | SHAR2 | Rubiaceae |
| madeiravine | Anredera cordifolia (Ten.) Steenis | BOGCO | ANCO6 | Basellaceae |
| Pacific madrone | Arbutus menziesii Pursh | ARDME | ARME | Ericaceae |
| maidencane | Panicum hemitomon Schultes | PANHE | PAHE2 | Poaceae |
| malachra | Malachra alceifolia Jacq. | MAAAL | MAAL4 | Malvaceae |
| alkali mallow | Malvella leprosa (Ortega) Krapov. | SIDHE | MALE3 | Malvaceae |
| bristly mallow | Modiola caroliniana (L.) G. Don | MODCA | MOCA | Malvaceae |
| bull mallow | Malva nicaeensis All. | MALNI | MANI2 | Malvaceae |
| common mallow | Malva neglecta Wallr. | MALNE | MANE | Malvaceae |
| curled mallow | Malva verticillata L. var. crispa L. | MALVE | MAVEC | Malvaceae |
| high mallow | Malva sylvestris L. | MALSI | MASY | Malvaceae |
| hispid false mallow | Malvastrum hispidum (Pursh) Hochr. | MAVHI | MAHI | Malvaceae |
| hollyhock mallow | Malva alcea L. | MALAL | MAAL | Malvaceae |
| little mallow | Malva parviflora L. | MALPA | MAPA5 | Malvaceae |
| low mallow | Malva pusilla Sm. | MALPU | MAPU5 | Malvaceae |
| musk mallow | Malva moschata L. | MALMO | MAMO2 | Malvaceae |
| Venice mallow | Hibiscus trionum L. | HIBTR | HITR | Malvaceae |
| maltesecross | Lychnis chalcedonica L. | LYHCH | LYCH3 | Caryophyllaceae |
| maltesecross | Silene chalcedonica (L.) E. H. L. Krause | LYHCH | Caryophyllaceae | |
| American mangrove | Rhizophora mangle L. | RHZMA | RHMA2 | Rhizophoracea |
| manilagrass | Zoysia matrella (L.) Merr. | ZOYMA | ZOMA2 | Poaceae |
| rattlesnake mannagrass | Glyceria canadensis (Michx.) Trin. | GLYCA | GLCA | Poaceae |
| reed mannagrass | Glyceria maxima (Hartm.) Holmb. | GLYMA | GLMA3 | Poaceae |
| tufted mannagrass | Glyceria septentrionalis Hitchc. | GLYSE | GLSE3 | Poaceae |
| Sierra manroot | Marah horridus (Congd.) S. T. Dunn | MBHHO | MAHO | Cucurbitaceae |
| common manzanita | Arctostaphylos manzanita Parry | ARYMA | ARMA | Ericaceae |
| eastwood manzanita | Arctostaphylos glandulosa Eastw. | ARYGD | ARGL3 | Ericaceae |
| greenleaf manzanita | Arctostaphylos patula Greene | ARYPA | ARPA6 | Ericaceae |
| whiteleaf manzanita | Arctostaphylos viscida Parry | ARYVI | ARVI4 | Ericaceae |
| bigleaf maple | Acer macrophyllum Pursh | ACRMA | ACMA3 | Sapindaceae |
| Norway maple | Acer platanoides L. | ACRPL | ACPL | Sapindaceae |
| red maple | Acer rubrum L. | ACRRB | ACRU | Sapindaceae |
| sugar maple | Acer saccharum Marshall | ACRSC | ACSA3 | Sapindaceae |
| sycamore maple | Acer pseudoplatanus L. | ACRPP | ACPS | Sapindaceae |
| vine maple | Acer circinatum Pursh | ACRCJ | ACCI | Sapindaceae |
| marabu | Dichrostachys cinerea (L.) Wight & Arn. | DIRCI | DICI2 | Fabaceae |
| marestail | Hippuris vulgaris L. | HPPVU | HIVU2 | Hippuridaceae |
| fetid marigold | Dyssodia papposa (Vent.) Hitchc. | DYSPA | DYPA | Asteraceae |
| field marigold | Calendula arvensis L. | CLDAR | CAAR | Asteraceae |
| wild marigold | Tagetes minuta L. | TAGMI | TAMI3 | Asteraceae |
| marijuana | Cannabis sativa L. | CNISA | CASA3 | Cannabaceae |
| wild marjoram | Origanum vulgare L. | ORIVU | ORVU | Lamiaceae |
| marshelder | Cyclachaena xanthiifolia (Nutt.) Fresen. | KYCXA | CYXA2 | Asteraceae |
| annual marshelder | Iva annua L. | IVAAN | IVAN2 | Asteraceae |
| matgrass | Nardus stricta L. | NADST | NAST3 | Poaceae |
| matrimony vine | Lycium barbarum L. | LYUHA | LYBA4 | Solanaceae |
| small matweed | Guilleminea densa (Humb. & Bonpl. ex Willd.) Moq. | GUMDE | GUDE | Amaranthaceae |
| mayten | Maytenus boaria Molina | MYUBO | MABO8 | Celastraceae |
| Asian mazus | Mazus pumilus (Burm. f.) Steenis | MAZJA | MAPU7 | Phrymaceae |
| tall meadow-rue | Thalictrum pubescens Pursh | THCPO | THPU2 | Ranunculaceae |
| meadowsweet | Spiraea alba Du Roi var. latifolia (Aiton) Dippel | SPVLF | SPALL | Rosaceae |
| black medic | Medicago lupulina L. | MEDLU | MELU | Fabaceae |
| medinilla | Medinilla venosa (Blume) Blume | MDJVE | MEVE3 | Melastomataceae |
| Arabian Mediterranean grass | Schismus arabicus Nees | SHIAR | SCAR | Poaceae |
| common Mediterranean grass | Schismus barbatus (L.) Thellung | SHIBA | SCBA | Poaceae |
| medusahead | Taeniatherum caput-medusae (L.) Nevski | ELYCM | TACA8 | Poaceae |
| melaleuca | Melaleuca quinquenervia (Cav.) S. T. Blake | MLAQU | MEQU | Myrtaceae |
| Banks melastoma | Melastoma malabathricum L. | MESMA | MEMA | Melastomataceae |
| amargo mequite | Prosopis articulata S. Watson | PRCAT | PRAR4 | Fabaceae |
| annual mercury | Mercurialis annua L. | MERAN | MEAN | Euphorbiaceae |
| cutleaf mermaidweed | Proserpinaca pectinata Lam. | PPQPE | PRPE | Haloragaceae |
| marsh mermaidweed | Proserpinaca palustris L. | PPQPA | PRPA3 | Haloragaceae |
| coppery mesembryanthemum | Malephora crocea (Jacq.) Schwantes | MPHCR | MACR3 | Aizoaceae |
| mesquite | Prosopis juliflora (Sw.) DC. | PRCJU | PRJU3 | Fabaceae |
| creeping mesquite | Prosopis strombulifera (Lam.) Benth. | PRCSF | PRST3 | Fabaceae |
| honey mesquite | Prosopis glandulosa Torr. var. glandulosa | PRCJG | PRGLG | Fabaceae |
| Syrian mesquite | Prosopis farcta (Banks & Sol.) J. F. Macbr. | PRCST | PRFA2 | Fabaceae |
| velvet mesquite | Prosopis velutina Wooton | PRCJV | PRVE | Fabaceae |
| western honey mesquite | Prosopis glandulosa Torr. var. torreyana (L. D. Benson) M. C. Johnst. | PRCJT | PRGLT | Fabaceae |
| Mexican tea | Dysphania ambrosioides (L.) Mosyakin & Clemants | CHEAM | DYAM | Chenopodiaceae |
| Mexican weed | Caperonia castaneifolia (L.) A. St.-Hil. | CNPCA | CACA41 | Euphorbiaceae |
| Miami mist | Phacelia purshii Buckley | PHCPU | PHPU3 | Boraginaceae |
| miconia | Miconia calvescens DC. | MICCA | MICA20 | Melastomataceae |
| white mignonette | Reseda alba L. | RESAL | REAL | Resedaceae |
| yellow mignonette | Reseda lutea L. | RESLU | RELU | Resedaceae |
| mile a minute | Mikania micrantha Kunth | MIKMI | MIMI5 | Asteraceae |
| African mile a minute | Mikania cordata (Burm. f.) B. L. Rob. | MIKCO | MICO16 | Asteraceae |
| blessed milkthistle | Silybum marianum (L.) Gaertn. | SLYMA | SIMA3 | Asteraceae |
| Canada milkvetch | Astragalus canadensis L. | ASACA | ASCA11 | Fabaceae |
| Columbia milkvetch | Astragalus miser Douglas var. serotinus (A. Gray) Barneby | ASAMS | ASMIS | Fabaceae |
| halfmoon milkvetch | Astragalus wootonii Sheldon | ASAWO | ASWO2 | Fabaceae |
| narrowleaf milkvetch | Astragalus pectinatus (Hook.) Douglas ex G. Don | ASAPE | ASPE5 | Fabaceae |
| Nuttall milkvetch | Astragalus nuttallianus DC. | ASANT | ASNU4 | Fabaceae |
| timber milkvetch | Astragalus miser Douglas | ASAMI | ASMI9 | Fabaceae |
| Tweedy milkvetch | Astragalus tweedyi Canby | ASATW | ASTW | Fabaceae |
| twogrooved milkvetch | Astragalus bisulcatus (Hook.) A. Gray | ASABI | ASBI2 | Fabaceae |
| Wasatch milkvetch | Astragalus miser Douglas var. oblongifolius (Rydb.) Cronquist | ASAMO | ASMIO | Fabaceae |
| Yellowstone milkvetch | Astragalus miser Douglas var. hylophilus (Rydb.) Barneby | ASAMH | ASMIH | Fabaceae |
| bloodflower milkweed | Asclepias curassavica L. | ASCCU | ASCU | Apocynaceae |
| broadleaf milkweed | Asclepias latifolia (Torr.) Raf. | ASCLT | ASLA4 | Apocynaceae |
| butterfly milkweed | Asclepias tuberosa L. | ASCTU | ASTU | Apocynaceae |
| climbing milkweed | Funastrum cynanchoides (Decne.) Schltr. | SAZCY | FUCY | Apocynaceae |
| common milkweed | Asclepias syriaca L. | ASCSY | ASSY | Apocynaceae |
| eastern whorled milkweed | Asclepias verticillata L. | ASCVE | ASVE | Apocynaceae |
| giant milkweed | Calotropis procera (Aiton) W. T. Aiton | CTRPR | CAPR | Apocynaceae |
| green milkweed | Asclepias viridiflora Pursh. | ASCVI | ASVI | Apocynaceae |
| labriform milkweed | Asclepias labriformis M.E. Jones | ASCLA | ASLA | Apocynaceae |
| Mexican whorled milkweed | Asclepias fascicularis Decne. | ASCFA | ASFA | Apocynaceae |
| plains milkweed | Asclepias pumila (A. Gray) Vail | ASCPM | ASPU | Apocynaceae |
| purple milkweed | Asclepias purpurascens L. | ASCPU | ASPU2 | Apocynaceae |
| showy milkweed | Asclepias speciosa Torr. | ASCSP | ASSP | Apocynaceae |
| swamp milkweed | Asclepias incarnata L. | ASCIN | ASIN | Apocynaceae |
| western whorled milkweed | Asclepias subverticillata (Gray) Vail | ASCSU | ASSU2 | Apocynaceae |
| woollypod milkweed | Asclepias eriocarpa Benth. | ASCER | ASER | Apocynaceae |
| browntop millet | Urochloa ramosa (L.) Nguyen | PANRA | URRA | Poaceae |
| foxtail millet | Setaria italica (L.) P. Beauv. | SETIT | SEIT | Poaceae |
| Japanese millet | Echinochloa frumentacea Link | ECHCF | ECFR | Poaceae |
| pearl millet | Pennisetum glaucum (L.) R. Br. | PESGL | PEGL2 | Poaceae |
| spring millet | Milium vernale M. Bieb. | MLISC | MIVE3 | Poaceae |
| Texas millet | Urochloa texana (Buckley) R. Webster | PANTE | URTE2 | Poaceae |
| wild proso millet | Panicum miliaceum L. | PANMI | PAMI2 | Poaceae |
| catclaw mimosa | Mimosa pigra L. | MIMPI | MIPI | Fabaceae |
| mimosa vine | Mimosa strigillosa Torr. & A. Gray | MIMST | MIST2 | Fabaceae |
| miners lettuce | Claytonia perfoliata Donn ex Willd. | CLAPE | CLPE | Montiaceae |
| apple mint | Mentha suaveolens Ehrh. | MENSU | MESU5 | Lamiaceae |
| bitter mint | Cantinoa mutabilis (Rich.) Harley & J. F. B. Pastore | HPYMU | CAMU2 | Lamiaceae |
| field mint | Mentha arvensis L. | MENAR | MEAR4 | Lamiaceae |
| horse mint | Mentha longifolia (L.) Huds. | MENLO | MELO8 | Lamiaceae |
| perilla mint | Perilla frutescens (L.) Britton | PRJFR | PEFR4 | Lamiaceae |
| roundleaf mint | Mentha x rotundifolia (L.) Huds. (pro sp.) [longifolia × suaveolens] | MENRO | MERO2 | Lamiaceae |
| mirror plant | Coprosma repens A. Rich. | CPMRE | CORE4 | Rubiaceae |
| miscanthus | Miscanthus floridulus (Labill.) Warb. ex K. Schum. & Lauterb. | MISFL | MIFL3 | Poaceae |
| missiongrass | Pennisetum polystachion (L.) Schult. | PESPO | PEPO4 | Poaceae |
| blue mistflower | Conoclinium coelestinum (L.) DC. | EUPCL | COCO13 | Asteraceae |
| European mistletoe | Viscum album L. | VISAL | VIAL2 | Santalaceae |
| oak mistletoe | Phoradendron villosum (Nutt.) Nutt. | PHQVV | PHVI9 | Viscaceae |
| Indian mock strawberry | Duchesnea indica (Andr.) Focke | DUCIN | DUIN | Rosaceae |
| molassesgrass | Melinis minutiflora Beauv. | MILMI | MEMI2 | Poaceae |
| moneywort | Lysimachia nummularia L. | LYSNU | LYNU | Primulaceae |
| seep monkeyflower | Erythranthe guttata (DC.) G. L. Nesom | MIUGU | MIGU | Phrymaceae |
| monochoria | Monochoria vaginalis (Burm. f.) C. Presl ex Kunth | MOOVA | MOVA | Pontederiaceae |
| arrowleaved monochoria | Monochoria hastata (L.) Solms | MOOHA | MOHA2 | Pontederiaceae |
| mooncactus | Harrisia martinii (Labour.) Britton | EEUMA | HAMA7 | Cactaceae |
| moonflower | Ipomoea alba L. | CLYAC | IPAL | Convolvulaceae |
| purple moonflower | Ipomoea muricata (L.) Jacq. | CLYMU | IPMU5 | Convolvulaceae |
| redberry moonseed | Cocculus carolinus (L.) DC. | COUCA | COCA | Menispermaceae |
| annual moonwort | Lunaria annua L. | LUNAN | LUAN | Brassicaceae |
| moorgrass | Molinia caerulea (L.) Moench | MOICO | MOCA2 | Poaceae |
| beach morningglory | Ipomoea pes-caprae (L.) R. Br. | IPOPC | IPPE | Convolvulaceae |
| bigroot morningglory | Ipomoea pandurata (L.) G. Mey. | IPOPA | IPPA | Convolvulaceae |
| blue morningglory | Ipomoea indica (Burm. f.) Merr. | IPOAC | IPIN | Convolvulaceae |
| bush morningglory | Ipomoea carnea Jacq. | IPOCN | IPCA5 | Convolvulaceae |
| Cairo morningglory | Ipomoea cairica (L.) Sweet | IPOCA | IPCA | Convolvulaceae |
| cotton morningglory | Ipomoea cordatotriloba Dennst. var. torreyana (A. Gray) D. Austin | IPOTT | IPCOT | Convolvulaceae |
| cypressvine morningglory | Ipomoea quamoclit L. | IPOQU | IPQU | Convolvulaceae |
| ivyleaf morningglory | Ipomoea hederacea Jacq. | IPOHE | IPHE | Convolvulaceae |
| ivyleaf red morningglory | Ipomoea hederifolia L. | IPOHF | IPHE2 | Convolvulaceae |
| Japanese morningglory | Ipomoea nil (L.) Roth | IPONI | IPNI | Convolvulaceae |
| multicolored morningglory | Ipomoea tricolor Cav. | IPOTO | IPTR3 | Convolvulaceae |
| palmleaf morningglory | Ipomoea wrightii A. Gray | IPOWR | IPWR | Convolvulaceae |
| pitted morningglory | Ipomoea lacunosa L. | IPOLA | IPLA | Convolvulaceae |
| red morningglory | Ipomoea coccinea L. | IPOCC | IPCO3 | Convolvulaceae |
| sharppod morningglory | Ipomoea cordatotriloba Dennst. | IPOTC | IPCO8 | Convolvulaceae |
| smallflower morningglory | Jacquemontia tamnifolia (L.) Griseb. | IAQTA | JATA | Convolvulaceae |
| swamp morningglory | Ipomoea aquatica Forssk. | IPOAQ | IPAQ | Convolvulaceae |
| tall morningglory | Ipomoea purpurea (L.) Roth | PHBPU | IPPU2 | Convolvulaceae |
| threelobe morningglory | Ipomoea triloba L. | IPOTR | IPTR2 | Convolvulaceae |
| tree morningglory | Ipomoea carnea Jacq. ssp. fistulosa (Mart. ex Choisy) D. F. Austin | IPOFI | IPCAF | Convolvulaceae |
| western morningglory | Calystegia occidentalis (A. Gray) Brummitt | CAGOC | CAOC6 | Convolvulaceae |
| Carolina mosquitofern | Azolla caroliniana Willd. | AZOCA | AZCA | Salviniaceae |
| Pacific mosquitofern | Azolla filiculoides Lam. | AZOFI | AZFI | Salviniaceae |
| pinnate mosquitofern | Azolla pinnata R. Br. | AZOPI | AZPI | Azollaceae |
| mother of thyme | Clinopodium acinos (L.) Kuntze | STIAC | CLAC5 | Lamiaceae |
| mother-of-thyme | Thymus praecox Opiz ssp. britannicus (Ronniger) Holub | THYPB | Lamiaceae | |
| motherwort | Leonurus cardiaca L. | LECCA | LECA2 | Lamiaceae |
| horehound motherwort | Chaiturus marrubiastrum (L.) Rchb. | CHMA18 | Lamiaceae | |
| Siberian motherwort | Leonurus sibiricus L. | LECSI | LESI | Lamiaceae |
| mountain whitethorn | Ceanothus cordulatus Kellogg | CEACD | CECO | Rhamnaceae |
| European mountain ash | Sorbus aucuparia L. | SOUAU | SOAU | Rosaceae |
| mousetail | Myosurus minimus L. | MYSMI | MYMI2 | Ranunculaceae |
| mudmats | Glossostigma diandrum (L.) Kunze | GLDI | Scrophulariaceae | |
| roundleaf mudplantain | Heteranthera reniformis Ruiz & Pav. | HETRE | HERE | Pontederiaceae |
| mugwort | Artemisia vulgaris L. | ARTVU | ARVU | Asteraceae |
| California mugwort | Artemisia douglasiana Besser ex Hook. | ARTDO | ARDO3 | Asteraceae |
| alkali muhly | Muhlenbergia asperifolia (Nees & Meyen ex Trin.) Parodi | MUHAS | MUAS | Poaceae |
| hairyawn muhly | Muhlenbergia capillaris (Lam.) Trin. | MUHCA | MUCA2 | Poaceae |
| wirestem muhly | Muhlenbergia frondosa (Poir.) Fernald | MUHFR | MUFR2 | Poaceae |
| red mulberry | Morus rubra L. | MORRU | MORU2 | Moraceae |
| white mulberry | Morus alba L. | MORAL | MOAL | Moraceae |
| mulberry weed | Fatoua villosa (Thunb.) Nakai | FTOVI | FAVI | Moraceae |
| northern mule's-ears | Wyethia amplexicaulis (Nutt.) Nutt. | WYHAM | WYAM | Asteraceae |
| whitehead mule's-ears | Wyethia helenioides (DC.) Nutt. | WYHHE | WYHE | Asteraceae |
| common mullein | Verbascum thapsus L. | VESTH | VETH | Scrophulariaceae |
| moth mullein | Verbascum blattaria L. | VESBL | VEBL | Scrophulariaceae |
| orange mullein | Verbascum phlomoides L. | VESPH | VEPH | Scrophulariaceae |
| purplestamen mullein | Verbascum virgatum Stokes | VESVI | VEVI2 | Scrophulariaceae |
| turkey mullein | Croton setigerus Hook. | ERMSE | CRSE11 | Euphorbiaceae |
| white mullein | Verbascum lychnitis L. | VESLY | VELY | Scrophulariaceae |
| muskmelon | Cucumis melo L. | CUMME | CUME | Cucurbitaceae |
| African mustard | Brassica tournefortii Gouan | BRSTO | BRTO | Brassicaceae |
| ball mustard | Neslia paniculata (L.) Desv. | NEAPA | NEPA3 | Brassicaceae |
| birdsrape mustard | Brassica rapa L. | BRSRR | BRRA | Brassicaceae |
| black mustard | Brassica nigra (L.) W. D. J. Koch | BRSNI | BRNI | Brassicaceae |
| blue mustard | Chorispora tenella (Pall.) DC. | COBTE | CHTE2 | Brassicaceae |
| dog mustard | Erucastrum gallicum (Willd.) O.E. Schulz | ERWGA | ERGA | Brassicaceae |
| elongated mustard | Brassica elongata Ehrh. | BRSEL | BREL2 | Brassicaceae |
| garlic mustard | Alliaria petiolata (M. Bieb.) Cavara & Grande | ALAPE | ALPE4 | Brassicaceae |
| hares ear mustard | Conringia orientalis (L.) Dumort. | CNHOR | COOR | Brassicaceae |
| hedge mustard | Sisymbrium officinale (L.) Scop. | SSYOF | SIOF | Brassicaceae |
| hill mustard | Bunias orientalis L. | BUNOR | BUOR | Brassicaceae |
| brown mustard | Brassica juncea (L.) Czern. | BRSJU | BRJU | Brassicaceae |
| oriental mustard | Sisymbrium orientale L. | SSYOR | SIOR4 | Brassicaceae |
| shortpod mustard | Hirschfeldia incana (L.) Lagr.-Foss. | HISIN | HIIN3 | Brassicaceae |
| Syrian mustard | Euclidium syriacum (L.) W. T. Aiton | EUISY | EUSY | Brassicaceae |
| tall hedge mustard | Sisymbrium loeselii L. | SSYLO | SILO3 | Brassicaceae |
| tumble mustard | Sisymbrium altissimum L. | SSYAL | SIAL2 | Brassicaceae |
| wallflower mustard | Erysimum cheiranthoides L. | ERYCH | ERCH9 | Brassicaceae |
| white mustard | Sinapis alba L. | SINAL | SIAL5 | Brassicaceae |
| wild mustard | Sinapis arvensis L. | SINAR | SIAR4 | Brassicaceae |
| myoporum | Myoporum laetum G. Forst. | MYMLA | MYLA5 | Scrophulariaceae |
| brittleleaf naiad | Najas minor All. | NAIMI | NAMI | Hydrocharitaceae |
| grassy naiad | Najas graminea Raffeneau-Delile | NAIGR | NAGR2 | Hydrocharitaceae |
| hollyleaf naiad | Najas marina L. | NAIMA | NAMA | Hydrocharitaceae |
| slender naiad | Najas flexilis (Willd.) Rostk. & Schmidt | NAIFL | NAFL | Hydrocharitaceae |
| southern naiad | Najas guadalupensis (Spreng.) Magnus | NAIGU | NAGU | Hydrocharitaceae |
| nannyberry | Viburnum lentago L. | VIBLE | VILE | Adoxaceae |
| napiergrass | Pennisetum purpureum Schumach. | PESPU | PEU2 | Poaceae |
| garden nasturtium | Tropaeolum majus L. | TOPMA | TRMA7 | Tropaeolaceae |
| Natal grass | Melinis repens (Willd.) Zizka | RHYRE | MERE9 | Poaceae |
| needleleaf navarretia | Navarretia intertexta (Benth.) Hook. | NAVIN | NAIN2 | Polemoniaceae |
| nechamandra | Nechamandra alternifolia (Roxb.) Thwaites | LGARO | NEAL2 | Hydrocharitaceae |
| needle and thread | Hesperostipa comata (Trin. & Rupr.) Barkworth | STDCO | HECO26 | Poaceae |
| nodding needlegrass | Nassella cernua (Stebbins & R.M. Love) Barkworth | STDCE | NACE | Poaceae |
| American nettle | Urtica dioica L. ssp. holosericea (Nutt.) Thorne | URTGH | URDIH | Urticaceae |
| burning nettle | Urtica urens L. | URTUR | URUR | Urticaceae |
| slender nettle | Urtica dioica L. ssp. gracilis (Aiton) Selander | URTLY | URDIG | Urticaceae |
| southern nettle | Urtica chamaedryoides Pursh | URTCH | URCH3 | Urticaceae |
| stinging nettle | Urtica dioica L. | URTDI | URDI | Urticaceae |
| yellow nickers | Caesalpinia bonduc (L.) Roxb. | CAEBO | CABO6 | Fabaceae |
| American black nightshade | Solanum americanum Mill. | SOLAM | SOAM | Solanaceae |
| bittersweet nightshade | Solanum dulcamara L. | SOLDU | SODU | Solanaceae |
| black nightshade | Solanum nigrum L. | SOLNI | SONI | Solanaceae |
| cutleaf nightshade | Solanum triflorum Nutt. | SOLTO | SOTR | Solanaceae |
| eastern black nightshade | Solanum ptychanthum Dunal | SOPT7 | Solanaceae | |
| forked nightshade | Solanum furcatum Dunal | SOFU4 | Solanaceae | |
| fuzzyfruit nightshade | Solanum candidum Lindl. | SOLCW | SOCA22 | Solanaceae |
| green nightshade | Solanum physalifolium var. nitidibaccatum (Bitter) Edmonds | SOLPN | SOPHN | Solanaceae |
| greenspot nightshade | Solanum douglasii Dunal | SOLNJ | SODO | Solanaceae |
| hairy nightshade | Solanum physalifolium Rusby | SOLPS | SOPH | Solanaceae |
| heartleaf nightshade | Solanum cardiophyllum Lindl. | SOLCY | SOCA19 | Solanaceae |
| Jamaican nightshade | Solanum jamaicense Mill. | SOLJA | SOJA3 | Solanaceae |
| lanceleaf nightshade | Solanum lanceolatum Cav. | SOLLL | SOLA | Solanaceae |
| melonleaf nightshade | Solanum heterodoxum Dunal | SOLHD | SOHE | Solanaceae |
| nipplefruit nightshade | Solanum mammosum L. | SOLMM | SOMA2 | Solanaceae |
| purple nightshade | Solanum xanti A. Gray | SOLXN | SOXA | Solanaceae |
| shrub nightshade | Solanum robustum H.L. Wendl. | SOLRO | SORO3 | Solanaceae |
| silverleaf nightshade | Solanum elaeagnifolium Cav. | SOLEL | SOEL | Solanaceae |
| sticky nightshade | Solanum sisymbriifolium Lam. | SOLSI | SOSI | Solanaceae |
| twinleaf nightshade | Solanum diphyllum L. | SOLDI | SODI2 | Solanaceae |
| watermelon nightshade | Solanum citrullifolium A. Braun | SOLCF | SOCI | Solanaceae |
| wetland nightshade | Solanum tampicense Dunal | SOLTA | SOTA3 | Solanaceae |
| white margined nightshade | Solanum marginatum L. f. | SOLMG | SOMA | Solanaceae |
| woolly nightshade | Solanum mauritianum Scop. | SOLMR | SOMA3 | Solanaceae |
| nimblewill | Muhlenbergia schreberi J. F. Gmel. | MUHSC | MUSC | Poaceae |
| nipplewort | Lapsana communis L. | LAPCO | LACO3 | Asteraceae |
| niruri | Phyllanthus niruri L. | PYLNI | PHNI2 | Phyllanthaceae |
| nitgrass | Gastridium phleoides (Nees & Meyen) C. E. Hubb. | GATPH | GAPH2 | Poaceae |
| nits and lice | Hypericum drummondii (Grev. & Hook.) Torr. & A. Gray | HYPDR | HYDR | Hypericaceae |
| betonyleaf noseburn | Tragia betonicifolia Nutt. | TRDBT | TRBE4 | Euphorbiaceae |
| branched noseburn | Tragia ramosa Torr. | TRDST | TRRA5 | Euphorbiaceae |
| false nutsedge | Cyperus strigosus L. | CYPST | CYST | Cyperaceae |
| purple nutsedge | Cyperus rotundus L. | CYPRO | CYRO | Cyperaceae |
| yellow nutsedge | Cyperus esculentus L. | CYPES | CYES | Cyperaceae |
| black oak | Quercus kelloggii Newb. | QUEKE | QUKE | Fagaceae |
| blackjack oak | Quercus marilandica Münchh. | QUEMR | QUMA3 | Fagaceae |
| bluejack oak | Quercus incana W. Bartram | QUEIN | QUIN | Fagaceae |
| bur oak | Quercus macrocarpa Michx. | QUEMC | QUMA2 | Fagaceae |
| canyon live oak | Quercus chrysolepis Liebm. | QUECH | QUCH2 | Fagaceae |
| dwarf live oak | Quercus minima (Sarg.) Small | QUEMN | QUMI2 | Fagaceae |
| Gambel oak | Quercus gambelii Nutt. | QUEGA | QUGA | Fagaceae |
| huckleberry oak | Quercus vacciniifolia Kellogg | QUEVC | QUVA | Fagaceae |
| laurel oak | Quercus laurifolia Michx. | QUELF | QULA3 | Fagaceae |
| live oak | Quercus virginiana Mill. | QUEVI | QUVI | Fagaceae |
| myrtle oak | Quercus myrtifolia Willd. | QUEMT | QUMY | Fagaceae |
| Oregon oak | Quercus garryana Douglas ex Hook. | QUEGR | QUGA4 | Fagaceae |
| pin oak | Quercus palustris Münchh. | QUEPA | QUPA2 | Fagaceae |
| plateau oak | Quercus fusiformis Small | QUEFU | QUFU | Fagaceae |
| post oak | Quercus stellata Wangenh. | QUESL | QUST | Fagaceae |
| running oak | Quercus pumila Walter | QUEPM | QUPU80 | Fagaceae |
| scrub live oak | Quercus geminata Small | QUEGN | QUGE2 | Fagaceae |
| shinnery oak | Quercus havardii Rydb. | QUEHV | QUHA3 | Fagaceae |
| southern red oak | Quercus falcata Michx. | QUEFC | QUFA | Fagaceae |
| tanbark oak | Lithocarpus densiflorus (Hook. & Arn.) Rehder | LIADF | LIDE3 | Fagaceae |
| tanbark oak | Notholithocarpus densiflorus (Hook. & Arn.) P.S. Manos, C.H. Cannon, & S.H. Oh | LIADF | NODE3 | Fagaceae |
| turbinella oak | Quercus turbinella Greene | QUETB | QUTU2 | Fagaceae |
| turkey oak | Quercus laevis Walt. | QUELA | QULA2 | Fagaceae |
| water oak | Quercus nigra L. | QUENI | QUNI | Fagaceae |
| white oak | Quercus alba L. | QUEAL | QUAL | Fagaceae |
| willow oak | Quercus phellos L. | QUEPH | QUPH | Fagaceae |
| oat | Avena sativa L. | AVESA | AVSA | Poaceae |
| slender oat | Avena barbata Pott ex Link | AVEBA | AVBA | Poaceae |
| sterile oat | Avena sterilis L. | AVEST | AVST | Poaceae |
| wild oat | Avena fatua L. | AVEFA | AVFA | Poaceae |
| poverty oatgrass | Danthonia spicata (L.) P. Beauv. ex Roem. & Schult. | DANSP | DASP2 | Poaceae |
| tall oatgrass | Arrhenatherum elatius (L.) P. Beauv. ex J. Presl & C. Presl | ARREL | AREL3 | Poaceae |
| oceanspray | Holodiscus discolor (Pursh) Maxim. | HODDI | HODI | Rosaceae |
| okra | Abelmoschus esculentus (L.) Moench | ABMES | ABES | Malvaceae |
| old mans beard | Clematis vitalba L. | CLVVT | CLVI6 | Ranunculaceae |
| oldplainsman | Hymenopappus scabiosaeus L'Hér. var. corymbosus (Torr. & A. Gray) B. L. Turner | HYYSC | HYSCC | Asteraceae |
| oleander | Nerium oleander L. | NEROL | NEOL | Apocynaceae |
| olive | Olea europaea L. | OLVEU | OLEU | Oleaceae |
| Geyer onion | Allium geyeri S. Wats. | ALLGE | ALGE | Amaryllidaceae |
| narrowleaf onion | Allium amplectens Torr. | ALLAP | ALAM2 | Amaryllidaceae |
| panicled onion | Allium paniculatum L. | ALLPA | ALPA20 | Amaryllidaceae |
| tapertip onion | Allium acuminatum Hook. | ALLAC | ALAC4 | Amaryllidaceae |
| textile onion | Allium textile A. Nelson & J. F. Macbr. | ALLTE | ALTE | Amaryllidaceae |
| white onion | Allium neopolitanum Cirillo | ALLNE | ALNE3 | Amaryllidaceae |
| wild onion | Allium canadense L. | ALLCA | ALCA3 | Amaryllidaceae |
| onionweed | Asphodelus fistulosus L. | ASHFI | ASFI2 | Xanthorrhoeaceae |
| garden orach | Atriplex hortensis L. | ATXHO | ATHO | Chenopodiaceae |
| halberdleaf orach | Atriplex patula L. | ATXPA | ATPA4 | Chenopodiaceae |
| red orach | Atriplex rosea L. | ATXRO | ATRO | Chenopodiaceae |
| triangle orach | Atriplex prostrata Bouchér ex DC. | ATXHA | ATPR | Chenopodiaceae |
| orchardgrass | Dactylis glomerata L. | DACGL | DAGL | Poaceae |
| Osage orange | Maclura pomifera (Raf.) C. K. Schneid. | MACPO | MAPO | Moraceae |
| osier | Salix viminalis L. | SAXVI | SAVI2 | Salicaceae |
| buttercup oxalis | Oxalis pes-caprae L. | OXAPC | OXPE | Oxalidaceae |
| red oxalis | Oxalis rubra A. St.-Hil. | OXARU | OXRU | Oxalidaceae |
| smooth oxeye | Heliopsis helianthoides (L.) Sweet | HEFHE | HEHE5 | Asteraceae |
| bristly oxtongue | Helminthotheca echioides (L.) Holub | PICEC | HEEC3 | Asteraceae |
| hawkweed oxtongue | Picris hieracioides L. | PICHI | PIHI | Asteraceae |
| oxyspora | Oxyspora paniculata (D. Don) DC. | OXOPA | OXPA3 | Melastomataceae |
| paddymelon | Cucumis myriocarpus Naudin | CUMMY | CUMY | Cucurbitaceae |
| saw palmetto | Serenoa repens (W. Bartram) Small | SERRE | SERE2 | Arecaceae |
| palmgrass | Setaria palmifolia (J. Koenig) Stapf | SETPA | SEPA6 | Poaceae |
| Mexican palo verde | Parkinsonia aculeata L. | PAKAC | PAAC3 | Fabaceae |
| pampas grass | Cortaderia selloana (Schult. & Schult. f.) Asch & Graebn. | CDTSE | COSE4 | Poaceae |
| pangolagrass | Digitaria eriantha Steud. | DIGER | DIER | Poaceae |
| blue panicgrass | Panicum antidotale Retz. | PANAN | PAAN4 | Poaceae |
| Hillman panicgrass | Panicum hillmanii Chase | PANHI | PAHI3 | Poaceae |
| western panicgrass | Dichanthelium acuminatum (Sw.) Gould & C. A. Clark | DKTAC | DIACF | Poaceae |
| fall panicum | Panicum dichotomiflorum Michx. | PANDI | PADI | Poaceae |
| redtop panicum | Panicum rigidulum Bosc ex Nees | PANRI | PARI4 | Poaceae |
| sprawling panicum | Urochloa reptans (L.) Stapf | PANRP | URRE2 | Poaceae |
| pansy | Viola tricolor L. | VIOTR | VITR | Violaceae |
| field pansy | Viola bicolor Pursh | VIORA | VIBI | Violaceae |
| paper mulberry | Broussonetia papyrifera (L.) L'Hér ex Vent. | BRNPA | BRPA4 | Moraceae |
| dwarf papyrus | Cyperus prolifer Lam. | CYPPF | CYPR17 | Cyperaceae |
| paragrass | Urochloa mutica (Forssk.) T.Q. Nguyen | PANPU | URMU | Poaceae |
| paroquet-bur | Triumfetta rhomboidea Jacq. | TIUBA | TRRH | Tiliaceae |
| parrot feather watermilfoil | Myriophyllum aquaticum (Vell.) Verdc. | MYPBR | MYAQ2 | Haloragaceae |
| parsley piert | Aphanes arvensis L. | APHAR | APAR2 | Rosaceae |
| slender parsley piert | Aphanes microcarpa (Boiss. & Reut.) Rothm. | APHMI | APMI | Rosaceae |
| wild parsnip | Pastinaca sativa L. | PAVSA | PASA2 | Apiaceae |
| ragweed parthenium | Parthenium hysterophorus L. | PTNHY | PAHY | Asteraceae |
| partridgepea | Chamaecrista fasciculata (Michx.) Greene | CASFA | CHFA2 | Fabaceae |
| sensitive partridgepea | Chamaecrista nictitans (L.) Moench | CASNI | CHNI2 | Fabaceae |
| bull paspalum | Paspalum boscianum Flueggé | PASBO | PABO3 | Poaceae |
| field paspalum | Paspalum laeve Michx. | PASLA | PALA10 | Poaceae |
| Florida paspalum | Paspalum floridanum Michx. | PASFD | PAFL4 | Poaceae |
| ricegrass paspalum | Paspalum scrobiculatum L. | PASSC | PASC6 | Poaceae |
| seashore paspalum | Paspalum vaginatum Sw. | PASVA | PAVA | Poaceae |
| sour paspalum | Paspalum conjugatum P. J. Bergius | PASCO | PACO14 | Poaceae |
| thin paspalum | Paspalum setaceum Michx. | PASSA | PASE5 | Poaceae |
| water paspalum | Paspalum fluitans (Elliott) Kunth | PASFL | PAFL5 | Poaceae |
| pasqueflower | Anemone patens L. var. multifida Pritz. | PUSPM | ANPAM | Ranunculaceae |
| corkystem passionflower | Passiflora suberosa L. | PAQSU | PASU3 | Passifloraceae |
| maypop passionflower | Passiflora incarnata L. | PAQIN | PAIN6 | Passifloraceae |
| redfruit passionflower | Passiflora foetida L. | PAQFO | PAFO2 | Passifloraceae |
| yellow passionflower | Passiflora lutea L. | PAQLU | PALU2 | Passifloraceae |
| banana passionfruit | Passiflora mollissima (Kunth) L. H. Bailey | PAQMO | PAMO5 | Passifloraceae |
| wingleaf passionfruit | Passiflora bicornis Mill. | PABI5 | Passifloraceae | |
| royal paulownia | Paulownia tomentosa (Thunb.) Siebold & Zucc. ex Steud. | PAZTO | PATO2 | Paulowniaceae |
| pawpaw | Asimina triloba (L.) Dunal | ASITR | ASTR | Annonaceae |
| flag pawpaw | Asimina incana (W. Bartram) Exell | ASIIN | ASIN12 | Annonaceae |
| netleaf pawpaw | Asimina reticulata Shuttlew. ex Chapm. | ASIRE | ASRE7 | Annonaceae |
| Tangier pea | Lathyrus tingitanus L. | LTHTI | LATI | Fabaceae |
| peach | Prunus persica (L.) Batsch | PRNPS | PRPE3 | Rosaceae |
| peacocksplume | Falcataria moluccana (Miq.) Barneby & J. W. Grimes | PSZFA | FAMO | Fabaceae |
| Callery pear | Pyrus calleryana Decne. | PYUCA | PYCA80 | Rosaceae |
| birdseye pearlwort | Sagina procumbens L. | SAIPR | SAPR | Caryophyllaceae |
| dwarf pearlwort | Sagina apetala Ard. | SAIAP | SAAP | Caryophyllaceae |
| angled peavine | Lathyrus angulatus L. | LTHAG | LAAN3 | Fabaceae |
| everlasting peavine | Lathyrus latifolius L. | LTHLA | LALA4 | Fabaceae |
| flat peavine | Lathyrus sylvestris L. | LTHSY | LASY | Fabaceae |
| flatpod peavine | Lathyrus cicera L. | LTHCI | LACI | Fabaceae |
| grass peavine | Lathyrus sativus L. | LTHSA | LASA2 | Fabaceae |
| marsh peavine | Lathyrus palustris L. | LTHPA | LAPA4 | Fabaceae |
| meadow peavine | Lathyrus pratensis L. | LTHPR | LAPR | Fabaceae |
| rough peavine | Lathyrus hirsutus L. | LTHHI | LAHI2 | Fabaceae |
| Florida pellitory | Parietaria floridana Nutt. | PAIFL | PAFL3 | Urticaceae |
| Pennsylvania pellitory | Parietaria pensylvanica Muhl. ex Willd. | PAIPE | PAPE5 | Urticaceae |
| field pennycress | Thlaspi arvense L. | THLAR | THAR5 | Brassicaceae |
| thoroughwort pennycress | Noccaea perfoliata (L.) Al-Shehbaz | THLPE | MIPE8 | Brassicaceae |
| pennyroyal | Mentha pulegium L. | MENPU | MEPU | Lamiaceae |
| Asiatic pennywort | Centella asiatica (L.) Urb. | CLLAS | CEAS | Apiaceae |
| coastal plain pennywort | Hydrocotyle bonariensis Comm. ex Lam. | HYDBO | HYBO | Araliaceae |
| floating pennywort | Hydrocotyle ranunculoides L. f. | HYDRA | HYRA | Araliaceae |
| lawn pennywort | Hydrocotyle sibthorpioides Lam. | HYDSI | HYSI | Araliaceae |
| marsh pennywort | Hydrocotyle americana L. | HYDAM | HYAM | Araliaceae |
| water pennywort | Hydrocotyle umbellata L. | HYDUM | HYUM | Araliaceae |
| whorled pennywort | Hydrocotyle verticillata Thunb. | HYDVE | HYVE2 | Araliaceae |
| Eaton penstemon | Penstemon eatonii A. Gray | PEEEA | PEEA | Plantaginaceae |
| talus slope penstemon | Penstemon digitalis Nutt. ex Sims | PEEDI | PEDI | Plantaginaceae |
| spiked pepper | Piper aduncum L. | PIPAD | PIAD | Piperaceae |
| peppermint | Mentha x piperita L. (pro sp.) [aquatica × spicata] | MENPI | MEPI | Lamiaceae |
| Brazilian peppertree | Schinus terebinthifolius Raddi | SCITE | SCTE | Anacardiaceae |
| Peruvian peppertree | Schinus molle L. | SCIMO | SCMO | Anacardiaceae |
| peppervine | Ampelopsis arborea (L.) Koehne | AMCAR | AMAR5 | Vitaceae |
| clasping pepperweed | Lepidium perfoliatum L. | LEPPE | LEPE2 | Brassicaceae |
| field pepperweed | Lepidium campestre (L.) W. T. Aiton | LEPCA | LECA5 | Brassicaceae |
| greenflower pepperweed | Lepidium densiflorum Schrad. | LEPDE | LEDE | Brassicaceae |
| narrowleaf pepperweed | Lepidium ruderale L. | LEPRU | LERU | Brassicaceae |
| perennial pepperweed | Lepidium latifolium L. | LEPLA | LELA2 | Brassicaceae |
| sand pepperweed | Lepidium lasiocarpum Nutt. | LEPLC | LELA | Brassicaceae |
| southern pepperweed | Lepidium austrinum Small | LEPLO | LEAU3 | Brassicaceae |
| tongue pepperweed | Lepidium nitidum Nutt. | LEPNI | LENI | Brassicaceae |
| veiny pepperweed | Lepidium oblongum Small | LEPOB | LEOB | Brassicaceae |
| Virginia pepperweed | Lepidium virginicum L. | LEPVI | LEVI3 | Brassicaceae |
| European pepperwort | Marsilea quadrifolia L. | MASQU | MAQU | Marsileaceae |
| hairy pepperwort | Marsilea vestita Hook. & Grev. | MASMU | MAVE2 | Marsileaceae |
| big periwinkle | Vinca major L. | VINMA | VIMA | Apocynaceae |
| common periwinkle | Vinca minor L. | VINMI | VIMI2 | Apocynaceae |
| Madagascar periwinkle | Catharanthus roseus (L.) G. Don | CTURO | CARO14 | Apocynaceae |
| common persimmon | Diospyros virginiana L. | DOSVI | DIVI5 | Ebenaceae |
| seaside petunia | Calibrachoa parviflora (Juss.) D'Arcy | PEUPA | CAPA47 | Solanaceae |
| wild petunia | Ruellia caroliniensis (J. F. Gmel.) Steud. | RUECA | RUCA4 | Acanthaceae |
| great valley phacelia | Phacelia ciliata Benth. | PHCCI | PHCI2 | Boraginaceae |
| longstalk phyllanthus | Phyllanthus tenellus Roxb. | PYLTE | PHTE5 | Phyllanthaceae |
| pickerelweed | Pontederia cordata L. | POFCO | POCO14 | Pontederiaceae |
| roundleaved pickerelweed | Pontederia rotundifolia L. | POFRO | PORO12 | Pontederiaceae |
| fringed pigweed | Amaranthus fimbriatus (Torr.) Benth. ex S. Watson | AMAFI | AMFI | Amaranthaceae |
| prostrate pigweed | Amaranthus blitoides S. Watson | AMABL | AMBL | Amaranthaceae |
| redroot pigweed | Amaranthus retroflexus L. | AMARE | AMRE | Amaranthaceae |
| Russian pigweed | Axyris amaranthoides L. | AXYAM | AXAM | Chenopodiaceae |
| smooth pigweed | Amaranthus hybridus L. | AMACH | AMHY | Amaranthaceae |
| tumble pigweed | Amaranthus albus L. | AMAAL | AMAL | Amaranthaceae |
| winged pigweed | Cycloloma atriplicifolium (Spreng.) J. M. Coult. | CYMAT | CYAT | Chenopodiaceae |
| pilipiliula | Chrysopogon aciculatus (Retz.) Trin. | CYSAC | CHAC | Poaceae |
| scarlet pimpernel | Anagallis arvensis L. | ANGAR | ANAR | Primulaceae |
| Monterey pine | Pinus radiata D. Don | PIURA | PIRA2 | Pinaceae |
| pineapple weed | Matricaria discoidea DC. | MATMT | MADI6 | Asteraceae |
| pineweed | Hypericum gentianoides (L.) Britton, Sterns & Poggenb. | HYPGE | HYGE | Hypericaceae |
| pingue | Hymenoxys richardsonii (Hook.) Cockerell var. floribunda (A. Gray) K. L. Parker | HYXRF | HYRIF | Asteraceae |
| childing pink | Petrorhagia prolifera (L.) P. W. Ball & Heywood | PERPR | PEPR4 | Caryophyllaceae |
| Deptford pink | Dianthus armeria L. | DINAR | DIAR | Caryophyllaceae |
| hairy pink | Petrorhagia dubia (Raf.) G. López & Romo | PERVE | PEDU2 | Caryophyllaceae |
| proliferous pink | Petrorhagia nanteuilii (Burnat) P. W. Ball & Heywood | PERNA | PENA2 | Caryophyllaceae |
| pitscalegrass | Mnesithea granularis (L.) de Koning & Sosef | HAKGR | MNGR2 | Poaceae |
| blackseed plantain | Plantago rugelii Decne. | PLARU | PLRU | Plantaginaceae |
| bracted plantain | Plantago aristata Michx. | PLAAR | PLAR3 | Plantaginaceae |
| broadleaf plantain | Plantago major L. | PLAMA | PLMA2 | Plantaginaceae |
| buckhorn plantain | Plantago lanceolata L. | PLALA | PLLA | Plantaginaceae |
| cutleaf plantain | Plantago coronopus L. | PLACO | PLCO3 | Plantaginaceae |
| dwarf plantain | Plantago pusilla Nutt. | PLAPU | PLPU | Plantaginaceae |
| hoary plantain | Plantago media L. | PLAME | PLME | Plantaginaceae |
| paleseed plantain | Plantago virginica L. | PLAVI | PLVI | Plantaginaceae |
| prairie plantain | Plantago elongata Pursh | PLAEL | PLEL | Plantaginaceae |
| slender plantain | Plantago heterophylla Nutt. | PLAHE | PLHE2 | Plantaginaceae |
| woolly plantain | Plantago patagonica Jacq. | PLAPR | PLPA2 | Plantaginaceae |
| fragrant plantain lily | Hosta plantaginea (Lam.) Asch. | HSTPL | HOPL2 | Asparagaceae |
| American plum | Prunus americana Marshall | PRNAM | PRAM | Rosaceae |
| Chickasaw plum | Prunus angustifolia Marsh. | PRNAN | PRAN3 | Rosaceae |
| garden plum | Prunus domestica L. | PRNDO | PRDO | Rosaceae |
| giant plumegrass | Saccharum giganteum (Walter) Pers. | ERNGI | SAGI | Poaceae |
| silver plumegrass | Saccharum alopecuroides (L.) Nutt. | SACAL | SAAL21 | Poaceae |
| paradise poinciana | Caesalpinia gilliesii (Hook.) D. Dietr. | CAEGI | CAGI | Fabaceae |
| painted poinsettia | Euphorbia cyathophora Murray | EPHCT | EUCY | Euphorbiaceae |
| wild poinsettia | Euphorbia heterophylla L. | EPHHL | EUHE4 | Euphorbiaceae |
| poison hemlock | Conium maculatum L. | COIMA | COMA2 | Apiaceae |
| eastern poison-ivy | Toxicodendron radicans (L.) Kuntze | TOXRA | TORA2 | Anacardiaceae |
| western poison-ivy | Toxicodendron rydbergii (Small ex Rydb.) Greene | TOXRY | TORY | Anacardiaceae |
| Atlantic poison-oak | Toxicodendron pubescens Mill. | TOXQU | TOPU2 | Anacardiaceae |
| Pacific poison-oak | Toxicodendron diversilobum (Torr. & A. Gray) Greene | RHUDI | TODI | Anacardiaceae |
| poison-sumac | Toxicodendron vernix (L.) Kuntze | TOXVX | TOVE | Anacardiaceae |
| common pokeweed | Phytolacca americana L. | PHTAM | PHAM4 | Phytolaccaceae |
| polargrass | Arctagrostis latifolia (R. Br.) Griseb. | ARSLA | ARLA2 | Poaceae |
| annual polemonium | Polemonium micranthum Benth. | PMNMI | POMI | Polemoniaceae |
| policemans helmet | Impatiens glandulifera Royle | IPAGL | IMGL | Balsaminaceae |
| fourleaf polycarp | Polycarpon tetraphyllum (L.) L. | POYTE | POTE | Caryophyllaceae |
| ditch polypogon | Polypogon interruptus Kunth | POHIN | POIN7 | Poaceae |
| rabbitsfoot polypogon | Polypogon monspeliensis (L.) Desf. | POHMO | POMO5 | Poaceae |
| yellow pondlily | Nuphar polysepala Engelm. | NUPLP | NUPO2 | Nymphaeaceae |
| American pondweed | Potamogeton nodosus Poir. | PTMNO | PONO2 | Potamogetonaceae |
| curlyleaf pondweed | Potamogeton crispus L. | PTMCR | POCR3 | Potamogetonaceae |
| fineleaf pondweed | Stuckenia filiformis (Pers.) Börner | PTMFI | STFI6 | Potamogetonaceae |
| flatstem pondweed | Potamogeton zosteriformis Fernald | PTMZO | POZO | Potamogetonaceae |
| floatingleaf pondweed | Potamogeton natans L. | PTMNA | PONA4 | Potamogetonaceae |
| Fries pondweed | Potamogeton friesii Rupr. | PTMFR | POFR3 | Potamogetonaceae |
| horned pondweed | Zannichellia palustris L. | ZAIPA | ZAPA | Potamogetonaceae |
| Illinois pondweed | Potamogeton illinoensis Morong | PTMIL | POIL | Potamogetonaceae |
| largeleaf pondweed | Potamogeton amplifolius Tuckerman | PTMAM | POAM5 | Potamogetonaceae |
| leafy pondweed | Potamogeton foliosus Raf. | PTMFO | POFO3 | Potamogetonaceae |
| ribbonleaf pondweed | Potamogeton epihydrus Raf. | PTMEP | POEP2 | Potamogetonaceae |
| Richardson pondweed | Potamogeton richardsonii (A. Benn.) Rydb. | PTMRI | PORI2 | Potamogetonaceae |
| sago pondweed | Stuckenia pectinata (L.) Börner | PTMPE | STPE15 | Potamogetonaceae |
| small pondweed | Potamogeton pusillus L. | PTMPU | POPU7 | Potamogetonaceae |
| variableleaf pondweed | Potamogeton gramineus L. | PTMGR | POGR8 | Potamogetonaceae |
| waterthread pondweed | Potamogeton diversifolius Raf. | PTMDF | PODI | Potamogetonaceae |
| whitestem pondweed | Potamogeton praelongus Wulfen | PTMPR | POPR5 | Potamogetonaceae |
| poorjoe | Diodia teres Walter | DIQTE | DITE2 | Rubiaceae |
| Torrey popcornflower | Plagiobothrys torreyi (A. Gray) A. Gray | PGBTO | PLTO | Boraginaceae |
| valley popcornflower | Plagiobothrys canescens Benth. | ERRCA | PLCA2 | Boraginaceae |
| balsam poplar | Populus balsamifera L. | POPBA | POBA2 | Salicaceae |
| white poplar | Populus alba L. | POPAL | POAL7 | Salicaceae |
| California poppy | Eschscholzia californica Cham. | ESHCA | ESCA2 | Papaveraceae |
| corn poppy | Papaver rhoeas L. | PAPRH | PARH2 | Papaveraceae |
| field poppy | Papaver dubium L. | PAPDU | PADU | Papaveraceae |
| opium poppy | Papaver somniferum L. | PAPSO | PASO2 | Papaveraceae |
| pinnate poppy | Papaver argemone L. | PAPAR | PAAR3 | Papaveraceae |
| plume poppy | Bocconia frutescens L. | BOCFR | BOFR2 | Papaveraceae |
| red horn poppy | Glaucium corniculatum (L.) Rudolph | GUCCO | GLCO3 | Papaveraceae |
| Roemer poppy | Roemeria refracta DC. | ROERE | RORE | Papaveraceae |
| plains poppymallow | Callirhoe alcaeoides (Michx.) A. Gray | COEAL | CAAL | Malvaceae |
| purple poppymallow | Callirhoe involucrata (Torr. & A. Gray) A. Gray | COEIN | CAIN2 | Malvaceae |
| porcelain berry | Ampelopsis glandulosa (Wall.) Momiy. var. brevipedunculata (Maxim.) Momiy. | AMCBR | AMGLB | Vitaceae |
| porcupinegrass | Hesperostipa spartea (Trin.) Barkworth | STDSP | HESP11 | Poaceae |
| possum haw | Ilex decidua Walter | ILEDE | ILDE | Aquifoliaceae |
| Nuttall povertyweed | Blitum nuttallianum Schult. | MOPNU | MONU | Chenopodiaceae |
| prairie indigo | Baptisia alba (L.) Vent. var. macrophylla (Larisey) Isely | BAPAM | BAALM | Fabaceae |
| African pricklegrass | Crypsis vaginiflora (Forssk.) Opiz | KPSVA | CRVA2 | Poaceae |
| foxtail pricklegrass | Crypsis alopecuriodes (Piller & Mitterp.) Schrad. | HLEAL | CRAL2 | Poaceae |
| swamp pricklegrass | Crypsis schoenoides (L.) Lam. | HLESC | CRSC | Poaceae |
| annual pricklepoppy | Argemone polyanthemos (Fedde) G.B. Ownbey | ARGPL | ARPO2 | Papaveraceae |
| bluestem pricklepoppy | Argemone albiflora Hornem. | ARGAL | ARAL3 | Papaveraceae |
| hedgehog pricklepoppy | Argemone squarrosa Greene | ARGSQ | ARSQ | Papaveraceae |
| Mexican pricklepoppy | Argemone mexicana L. | ARGME | ARME4 | Papaveraceae |
| prickly-ash | Zanthoxylum americanum Mill. | ZANAM | ZAAM | Rutaceae |
| brittle pricklypear | Opuntia fragilis (Nutt.) Haw. | OPUFR | OPFR | Cactaceae |
| eastern pricklypear | Opuntia humifusa (Raf.) Raf. var. austrina (Small) Dress | OPUHA | OPHUA2 | Cactaceae |
| erect pricklypear | Cylindropuntia spinosior (Engelm.) F.M. Knuth | OPUSP | CYSP8 | Cactaceae |
| erect pricklypear | Opuntia stricta (Haw.) Haw. var. dillenii (Ker Gawl.) L. D. Benson | OPUDI | OPSTD | Cactaceae |
| jointed pricklypear | Opuntia aurantiaca Lindl. | OPUAU | OPAU10 | Cactaceae |
| Lindheimer pricklypear | Opuntia engelmannii Salm-Dyck ex Engelm. var. lindheimeri (Engelm.) B. D. Parfitt & Pinkava | OPULI | OPENL | Cactaceae |
| plains pricklypear | Opuntia polyacantha Haw. | OPUPO | OPPO | Cactaceae |
| spreading pricklypear | Opuntia humifusa (Raf.) Raf. | OPUHU | OPHU | Cactaceae |
| pride of Madeira | Echium candicans L. f. | EHICA | ECCA5 | Boraginaceae |
| water primrose | Ludwigia hexapetala (Hook. & Arn.) Zardini, Gu & P. H. Raven | LUDUR | LUHE5 | Onagraceae |
| Peruvian primrose willow | Ludwigia peruviana (L.) H. Hara | LUDPV | LUPE6 | Onagraceae |
| longfruited primrose willow | Ludwigia octovalvis (Jacq.) P. H. Raven | LUDOC | LUOC | Onagraceae |
| princess feather | Persicaria orientalis (L.) Spach | POLOR | PEOR9 | Polygonaceae |
| Amur privet | Ligustrum obtusifolium Siebold & Zucc. ssp. suave (Kitag.) Kitag. | LIGAM | Oleaceae | |
| border privet | Ligustrum obtusifolium Siebold & Zucc. | LIGOB | LIOB | Oleaceae |
| California privet | Ligustrum ovalifolium Hassk. | LIGOV | LIOV | Oleaceae |
| Chinese privet | Ligustrum sinense Lour. | LIGSI | LISI | Oleaceae |
| European privet | Ligustrum vulgare L. | LIGVU | LIVU | Oleaceae |
| glossy privet | Ligustrum lucidum W. T. Aiton | LIGLU | LILU2 | Oleaceae |
| Japanese privet | Ligustrum japonicum Thunb. | LIGJA | LIJA | Oleaceae |
| psyllium | Plantago arenaria Waldst. & Kit. | PLAIN | PLAR6 | Plantaginaceae |
| hoary puccoon | Lithospermum canescens (Michx.) Lehm. | LITCA | LICA12 | Boraginaceae |
| punagrass | Amelichloa brachychaeta (Godr.) Arriaga & Barkworth | STDBR | ACBR5 | Poaceae |
| puncturevine | Tribulus terrestris L. | TRBTE | TRTE | Zygophyllaceae |
| purpletop | Tridens flavus (L.) Hitchc. | TRSFL | TRFL2 | Poaceae |
| common purslane | Portulaca oleracea L. | POROL | POOL | Portulacaceae |
| horse purslane | Trianthema portulacastrum L. | TRTPO | TRPO2 | Aizoaceae |
| Paraguayan purslane | Portulaca amilis Speg. | POAM13 | Portulacaceae | |
| pink purslane | Portulaca pilosa L. | PORPI | POPI3 | Portulacaceae |
| Brazil pusley | Richardia brasiliensis Gomes | RCHBR | RIBR2 | Rubiaceae |
| Florida pusley | Richardia scabra L. | RCHSC | RISC | Rubiaceae |
| Canada pussytoes | Antennaria howellii ssp. canadensis (Greene) Bayer | ANXCA | ANHOC | Asteraceae |
| field pussytoes | Antennaria neglecta Greene | ANXNE | ANNE | Asteraceae |
| plantainleaf pussytoes | Antennaria plantaginifolia (L.) Richardson | ANXPL | ANPL | Asteraceae |
| sand pygmyweed | Crassula connata (Ruiz & Pav.) A. Berger | CSBCN | CRCO34 | Crassulaceae |
| quackgrass | Elymus repens (L.) Gould | AGRRE | ELRE4 | Poaceae |
| big quakinggrass | Briza maxima L. | BRZMA | BRMA | Poaceae |
| little quakinggrass | Briza minor L. | BRZMI | BRMI2 | Poaceae |
| queen of the meadow | Filipendula ulmaria (L.) Maxim. | FIIUL | FIUL | Rosaceae |
| queen of the prairie | Filipendula rubra (Hill) B.L. Robins. | FIIRU | FIRU2 | Rosaceae |
| rabbitbells | Crotalaria rotundifolia J. F. Gmel. | CVTRO | CRRO5 | Fabaceae |
| desert rabbitbrush | Ericameria paniculata (A. Gray) Rydb. | CYTPN | ERPA29 | Asteraceae |
| Douglas rabbitbrush | Chrysothamnus viscidiflorus (Hook.) Nutt. | CYTVI | CHVI8 | Asteraceae |
| gray rabbitbrush | Ericameria nauseosa (Pall. ex Pursh) G. L. Nesom & G. I. Baird | CYTNA | ERNA10 | Asteraceae |
| greenplume rabbitbrush | Ericameria nauseosa (Pall. ex Pursh) G. L. Nesom & Baird ssp. nauseosa var. glabrata (Gray) Nesom & Baird | CYTNG | ERNAG | Asteraceae |
| Parry rabbitbrush | Ericameria parryi (A. Gray) G. L. Nesom & G. I. Baird | CYTPA | ERPA30 | Asteraceae |
| southwest rabbitbrush | Lorandersonia pulchella (Gray) Urbatsch, R. P. Roberts & Neubig | CYTPU | CHPU4 | Asteraceae |
| radish | Raphanus sativus L. | RAPSR | RASA2 | Brassicaceae |
| wild radish | Raphanus raphanistrum L. | RAPRA | RARA2 | Brassicaceae |
| redflower ragleaf | Crassocephalum crepidioides (Benth.) S. Moore | CRSCR | CRCR9 | Asteraceae |
| blood ragweed | Ambrosia trifida L. var. texana Scheele | AMBTT | AMTRT | Asteraceae |
| common ragweed | Ambrosia artemisiifolia L. | AMBEL | AMAR2 | Asteraceae |
| false ragweed | Ambrosia tenuifolia Spreng. | AMBTE | AMTE5 | Asteraceae |
| giant ragweed | Ambrosia trifida L. | AMBTR | AMTR | Asteraceae |
| lanceleaf ragweed | Ambrosia bidentata Michx. | AMBBI | AMBI2 | Asteraceae |
| western ragweed | Ambrosia psilostachya DC. | AMBPS | AMPS | Asteraceae |
| golden ragwort | Packera aurea (L.) Á. Löve & D. Löve | SENAU | PAAU3 | Asteraceae |
| Madagascar ragwort | Senecio madagascariensis Poir. | SENMD | SEMA15 | Asteraceae |
| Oxford ragwort | Senecio squalidus L. | SENSQ | SESQ | Asteraceae |
| purple ragwort | Senecio elegans L. | SENEG | SEEL | Asteraceae |
| tansy ragwort | Senecio jacobaea L. | SENJA | SEJA | Asteraceae |
| rapeseed | Brassica napus L. | BRSNN | BRNA | Brassicaceae |
| American red raspberry | Rubus idaeus L. ssp. strigosus (Michx.) Focke | RUBSG | RUIDS2 | Rosaceae |
| European red raspberry | Rubus idaeus L. | RUBID | RUID | Rosaceae |
| hill raspberry | Rubus niveus Thunb. | RUBNI | RUNI4 | Rosaceae |
| Molucca raspberry | Rubus moluccanus L. | RUBMO | RUMO4 | Rosaceae |
| Molucca raspberry | Rubus sieboldii Blume | RUBSI | RUSI4 | Rosaceae |
| western raspberry | Rubus leucodermis Douglas ex Torr. & A. Gray | RUBLE | RULE | Rosaceae |
| wine raspberry | Rubus phoenicolasius Maxim. | RUBPH | RUPH | Rosaceae |
| rattlebox | Crotalaria sagittalis L. | CVTSA | CRSA4 | Fabaceae |
| Ethiopian rattlebox | Crotalaria brevidens Benth. | CVTBD | CRBR8 | Fabaceae |
| wedgeleaf rattlebox | Crotalaria retusa L. | CVTRE | CRRE4 | Fabaceae |
| Drummond rattlebush | Sesbania drummondii (Rydb.) Cory | SEBDR | SEDR | Fabaceae |
| rattlesnakeweed | Hieracium venosum L. | HIEVE | HIVE | Asteraceae |
| ravennagrass | Saccharum ravennae (L.) L. | ERNRA | SARA3 | Poaceae |
| eastern redcedar | Juniperus virginiana L. | IUPVI | JUVI | Cupressaceae |
| southern redcedar | Juniperus virginiana L. var. silicicola (Small) A. E. Murray | IUPSL | JUVIS | Cupressaceae |
| redmaids | Calandrinia ciliata (Ruiz & Pavón) DC. | CLNCM | CACI2 | Montiaceae |
| Carolina redroot | Lachnanthes caroliniana (Lam.) Dandy | LAHTI | LACA5 | Haemodoraceae |
| redstem | Ammannia coccinea Rottb. | AMMCO | AMCO | Lythraceae |
| eared redstem | Ammannia auriculata Willd. | AMMAU | AMAU2 | Lythraceae |
| redtop | Agrostis gigantea Roth | AGSGI | AGGI2 | Poaceae |
| redvine | Brunnichia ovata (Walter) Shinners | BRVCI | BROV4 | Polygonaceae |
| redweed | Melochia corchorifolia L. | MEOCO | MECO4 | Sterculiaceae |
| common reed | Phragmites australis (Cav.) Trin. ex Steud. | PHRCO | PHAU7 | Poaceae |
| giant reed | Arundo donax L. | ABKDO | ARDO4 | Poaceae |
| chee reedgrass | Calamagrostis epigejos (L.) Roth | CLMEP | CAEP | Poaceae |
| rescuegrass | Bromus catharticus Vahl | BROCA | BRCA6 | Poaceae |
| sweet resinbush | Euryops multifidus (Thunb.) DC. | EYOMU | EUMU | Asteraceae |
| foxtail restharrow | Ononis alopecuroides L. | ONOAP | ONAL5 | Fabaceae |
| Rhodes grass | Chloris gayana Kunth | CHRGA | CHGA2 | Poaceae |
| rhodora | Rhododendron canadense (L.) Torr. | RHOCA | RHCA6 | Ericaceae |
| African red rice | Oryza punctata Kotschy ex Steud. | ORYPU | ORPU13 | Poaceae |
| brownbeard rice | Oryza rufipogon Griffiths | ORYRU | ORRU | Poaceae |
| including the red rice biotype rice | Oryza sativa L. | ORYSA | ORSA | Poaceae |
| longstamen rice | Oryza longistaminata A. Chev. & Roehr. | ORYLO | ORLO3 | Poaceae |
| American yellow rocket | Barbarea orthoceras Ledeb. | BAROR | BAOR | Brassicaceae |
| garden rocket | Eruca vesicaria (L.) Cav. | ERUVV | ERVE5 | Brassicaceae |
| London rocket | Sisymbrium irio L. | SSYIR | SIIR | Brassicaceae |
| Mediterranean rocket | Sisymbrium erysimoides Desf. | SSYER | SIER5 | Brassicaceae |
| sand rocket | Diplotaxis muralis (L.) DC. | DIPMU | DIMU2 | Brassicaceae |
| wall rocket | Diplotaxis tenuifolia (L.) DC. | DIPTE | DITE4 | Brassicaceae |
| yellow rocket | Barbarea vulgaris W. T. Aiton | BARVU | BAVU | Brassicaceae |
| gum rockrose | Cistus ladanifer L. | CSTLA | CILA10 | Cistaceae |
| pink rockrose | Cistus creticus L. | CSTIC | CICR3 | Cistaceae |
| Cherokee rose | Rosa laevigata Michx. | ROSLA | ROLA | Rosaceae |
| cinnamon rose | Rosa pendulina L. | ROSPE | ROPE4 | Rosaceae |
| climbing rose | Rosa setigera Michx. | ROSSG | ROSE2 | Rosaceae |
| dog rose | Rosa canina L. | ROSCN | ROCA3 | Rosaceae |
| double cinnamon rose | Rosa majalis J. Herrm. | ROSMJ | ROMA81 | Rosaceae |
| Macartney rose | Rosa bracteata J.C. Wendl | ROSBC | ROBR | Rosaceae |
| multiflora rose | Rosa multiflora Thunb. | ROSMU | ROMU | Rosaceae |
| prairie wild rose | Rosa arkansana Porter | ROSAK | ROAR3 | Rosaceae |
| prickly rose | Rosa acicularis Lindl. | ROSAC | ROAC | Rosaceae |
| rugosa rose | Rosa rugosa Thunb. | ROSRG | RORU | Rosaceae |
| Scotch rose | Rosa spinosissima L. | ROSPP | ROSP2 | Rosaceae |
| sweetbriar rose | Rosa rubiginosa L. | ROSRB | RORU82 | Rosaceae |
| Virginia rose | Rosa virginiana Mill. | ROSVI | ROVI2 | Rosaceae |
| Woods rose | Rosa woodsii Lindl. | ROSWO | ROWO | Rosaceae |
| downy rosemyrtle | Rhodomyrtus tomentosa (Aiton) Hassk. | RHDTO | RHTO | Myrtaceae |
| fringed rosettegrass | Dichanthelium strigosum (Muhl. ex Elliott) Freckmann | DKTST | DISTL | Poaceae |
| roundseed rosettegrass | Dichanthelium sphaerocarpon (Elliott) Gould | PANSP | DISP2 | Poaceae |
| woolly rosettegrass | Dichanthelium scabriusculum (Elliott) Gould & C. A. Clark | DKTSC | DISC2 | Poaceae |
| cup rosinweed | Silphium perfoliatum L. | SIPPE | SIPE2 | Asteraceae |
| showy rosinweed | Silphium radula Nutt. | SIPRA | SIRA2 | Asteraceae |
| wholeleaf rosinweed | Silphium integrifolium Michx. var. laeve Torr. & A. Gray | SIPIP | SIINL | Asteraceae |
| rotalla | Rotala rotundifolia (Buch.-Ham. ex Roxb.) Koehne | ROTRO | RORO7 | Lythraceae |
| bitter rubberweed | Hymenoxys odorata DC. | HYXOD | HYOD | Asteraceae |
| African rue | Peganum harmala L. | PEGHA | PEHA | Nitrariaceae |
| common rue | Ruta graveolens L. | RUAGR | RUGR3 | Rutaceae |
| Baltic rush | Juncus balticus Willd. | IUNBA | JUBA | Juncaceae |
| bog rush | Juncus biflorus Elliott | JUBI | Juncaceae | |
| flowering rush | Butomus umbellatus L. | BUTUM | BUUM | Butomaceae |
| needle rush | Juncus roemerianus Scheele | IUNRO | JURO | Juncaceae |
| slender rush | Juncus tenuis Willd. | IUNTE | JUTE | Juncaceae |
| soft rush | Juncus effusus L. | IUNEF | JUEF | Juncaceae |
| toad rush | Juncus bufonius L. | IUNBU | JUBU | Juncaceae |
| tufted rush | Juncus acuminatus Michx. | IUNAN | JUAC | Juncaceae |
| Russian olive | Elaeagnus angustifolia L. | ELGAN | ELAN | Elaeagnaceae |
| Russian thistle | Salsola tragus L. | SASKT | SATR12 | Chenopodiaceae |
| barbwire Russian thistle | Salsola paulsenii Litv. | SASPA | SAPA8 | Chenopodiaceae |
| barbwire Russian thistle | Salsola paulsenii Litv. | SASPA | SAPA8 | Chenopodiaceae |
| spineless Russian thistle | Salsola collina Pall. | SASCO | SACO8 | Chenopodiaceae |
| rustweed | Polypremum procumbens L. | POEPR | POPR4 | Tetrachondraceae |
| cereal rye | Secale cereale L. | SECCE | SECE | Poaceae |
| Italian ryegrass | Lolium perenne L. ssp. multiflorum (Lam.) Husnot | LOLMU | LOPEM2 | Poaceae |
| meadow ryegrass | Lolium pratense (Huds.) Darbysh. | FESPR | LOPR7 | Poaceae |
| perennial ryegrass | Lolium perenne L. | LOLPE | LOPE | Poaceae |
| poison ryegrass | Lolium temulentum L. | LOLTE | LOTE2 | Poaceae |
| rigid ryegrass | Lolium rigidum Gaudin | LOLRI | LORI | Poaceae |
| alkali sacaton | Sporobolus airoides (Torr.) Torr. | SPZAI | SPAI | Poaceae |
| Sacramento-bur | Triumfetta semitriloba Jacq. | TIUSE | TRSE4 | Tiliaceae |
| sacred bamboo | Nandina domestica Thunb. | NANDO | NADO | Berberidaceae |
| wild safflower | Carthamus oxyacantha M. Bieb. | CAUOX | CAOX6 | Asteraceae |
| blue sage | Salvia azurea Michx. ex Lam. | SALAZ | SAAZ | Lamiaceae |
| clary sage | Salvia sclarea L. | SALSC | SASC2 | Lamiaceae |
| lanceleaf sage | Salvia reflexa Hornem. | SALRE | SARE3 | Lamiaceae |
| lyreleaf sage | Salvia lyrata L. | SALLY | SALY2 | Lamiaceae |
| meadow sage | Salvia pratensis L. | SALPR | SAPR2 | Lamiaceae |
| Mediterranean sage | Salvia aethiopis L. | SALAE | SAAE | Lamiaceae |
| pitchers sage | Salvia azurea Michx. ex Lam. var. grandiflora Benth. | SALAG | SAAZG | Lamiaceae |
| wand sage | Salvia x superba Stapf [sylvestris x villicaulis] | SALSU | SASU11 | Lamiaceae |
| whorled sage | Salvia verticillata L. | SALVE | SAVE5 | Lamiaceae |
| big sagebrush | Artemisia tridentata Nutt. | ARTTR | ARTR2 | Asteraceae |
| fringed sagebrush | Artemisia frigida Willd. | ARTFR | ARFR4 | Asteraceae |
| sand sagebrush | Artemisia filifolia Torr. | ARTFI | ARFI2 | Asteraceae |
| silver sagebrush | Artemisia cana Pursh | ARTCN | ARCA13 | Asteraceae |
| common sagewort | Artemisia campestris L. | ARTCM | ARCA12 | Asteraceae |
| field sagewort | Artemisia campestris ssp. caudata (Michx.) H. M. Hall & Clem. | ARTCC | ARCAC | Asteraceae |
| salal | Gaultheria shallon Pursh | GAHSH | GASH | Ericaceae |
| salmonberry | Rubus spectabilis Pursh | RUBSP | RUSP | Rosaceae |
| common salsify | Tragopogon porrifolius L. | TROPS | TRPO | Asteraceae |
| meadow salsify | Tragopogon pratensis L. | TROPR | TRPR | Asteraceae |
| western salsify | Tragopogon dubius Scop. | TRODM | TRDU | Asteraceae |
| Australian saltbush | Atriplex semibaccata R. Br. | ATXSE | ATSE | Chenopodiaceae |
| fourwing saltbush | Atriplex canescens (Pursh) Nutt. | ATXCA | ATCA2 | Chenopodiaceae |
| saline saltbush | Atriplex subspicata (Nutt.) Rydb. | ATXSU | ATSU2 | Chenopodiaceae |
| Salton saltbush | Atriplex elegans (Moq.) D. Dietr. var. fasciculata (S. Watson) M. E. Jones | ATXEF | ATELF | Chenopodiaceae |
| silverscale saltbush | Atriplex argentea Nutt. | ATXAR | ATAR2 | Chenopodiaceae |
| wheelscale saltbush | Atriplex elegans (Moq.) D. Dietr. | ATXEL | ATEL | Chenopodiaceae |
| Wright saltbush | Atriplex wrightii S. Watson | ATXWR | ATWR | Chenopodiaceae |
| saltcedar | Tamarix ramosissima Ledeb. | TAAPE | TARA | Tamaricaceae |
| saltgrass | Distichlis spicata (L.) Greene | DISSP | DISP | Poaceae |
| Russian salttree | Halimodendron halodendron (Pall.) Voss | HADHA | HAHA8 | Fabaceae |
| common saltwort | Salsola kali L. | SASKA | SAKA | Chenopodiaceae |
| Mediterranean saltwort | Salsola vermiculata L. | SASVE | SAVE6 | Chenopodiaceae |
| eared salvinia | Salvinia auriculata Aubl. | SAVAU | SAAU | Salviniaceae |
| giant salvinia | Salvinia molesta Mitchell | SAVMO | SAMO5 | Salviniaceae |
| Herzog salvinia | Salvinia herzogii de la Sota | SAVHE | SAHE7 | Salviniaceae |
| lobed salvinia | Salvinia biloba Raddi | SAVBI | SABI9 | Salviniaceae |
| dune sandbur | Cenchrus tribuloides L. | CCHTR | CETR | Poaceae |
| field sandbur | Cenchrus spinifex Cav. | CCHEC | CESP4 | Poaceae |
| longspine sandbur | Cenchrus longispinus (Hack.) Fernald | CCHLO | CELO3 | Poaceae |
| southern sandbur | Cenchrus echinatus L. | CCHEC | CEEC | Poaceae |
| Boccone sandspurry | Spergularia bocconii (Scheele) Foucaud ex Merino | SPBBO | SPBO | Caryophyllaceae |
| marine sandspurry | Spergularia maritima (All.) Chiov. | SPBMT | SPMA10 | Caryophyllaceae |
| red sandspurry | Spergularia rubra (L.) J. Presl & C. Presl | SPBRU | SPRU | Caryophyllaceae |
| saltmarsh sandspurry | Spergularia marina (L.) Griseb. | SPBMA | SPMA2 | Caryophyllaceae |
| grove sandwort | Moehringia lateriflora (L.) Fenzl | MGJLA | MOLA6 | Caryophyllaceae |
| thymeleaf sandwort | Arenaria serpyllifolia L. | ARISE | ARSE2 | Caryophyllaceae |
| saramolla grass | Ischaemum rugosum Salisb. | ISCRU | ISRU | Poaceae |
| sarsparilla vine | Smilax pumila Walter | SMIPU | SMPU | Smilacaceae |
| sassafras | Sassafras albidum (Nutt.) Nees | SSAAL | SAAL5 | Lauraceae |
| satintail | Imperata brevifolia Vasey | IMPBE | IMBR2 | Poaceae |
| Brazilian satintail | Imperata brasiliensis Trin. | IMPBR | IMBR | Poaceae |
| summer savory | Satureja hortensis L. | STIHO | SAHO3 | Lamiaceae |
| cat sawbriar | Smilax glauca Walter | SMIGL | SMGL | Smilacaceae |
| sawgrass | Cladium mariscus (L.) Pohl ssp. jamaicense (Crantz) Kuk. | CLKJA | CLMAJ | Cyperaceae |
| spreading scaleseed | Spermolepis divaricata (Walter) Raf. ex Ser. | SMPDI | SPDI2 | Apiaceae |
| scouringrush | Equisetum hyemale L. | EQUHY | EQHY | Equisetaceae |
| smooth scouringrush | Equisetum laevigatum A. Braun | EQULA | EQLA | Equisetaceae |
| lemon scurfpea | Psoralidium lanceolatum (Pursh) Rydb. | PSRLA | PSLA3 | Fabaceae |
| sea fig | Carpobrotus chilensis (Molina) N.E. Br. | CBSCH | CACH38 | Aizoaceae |
| American sea rocket | Cakile edentula (Bigelow) Hook. | CAKED | CAED | Brassicaceae |
| European sea rocket | Cakile maritima Scop. | CAKMA | CAMA | Brassicaceae |
| aggregate sedge | Cyperus aggregatus (Willd.) Endl. | CYPAK | CYAG | Cyperaceae |
| annual sedge | Cyperus compressus L. | CYPCP | CYCO | Cyperaceae |
| aromatic sedge | Cyperus squarrosus L. | MAPSQ | CYSQ | Cyperaceae |
| beaked sedge | Carex rostrata Stokes | CRXRO | CARO6 | Cyperaceae |
| bloodscale sedge | Cyperus sanguinolentus Vahl | CYPSA | CYSA10 | Cyperaceae |
| brown speckled sedge | Cyperus sphacelatus Rottb. | CYPSP | CYSP3 | Cyperaceae |
| Buckley sedge | Cyperus retroflexus Buckley | CYPRX | CYRE14 | Cyperaceae |
| cuspidate sedge | Cyperus cuspidatus Kunth | CYPCU | CYCU | Cyperaceae |
| cylindric sedge | Cyperus retrorsus Chapm. | CYPRT | CYRE5 | Cyperaceae |
| deeproot sedge | Cyperus entrerianus Boeck. | CYPEN | CYEN2 | Cyperaceae |
| foxtail sedge | Cyperus alopecuroides Rottb. | CYPAO | CYAL6 | Cyperaceae |
| Frank sedge | Carex frankii Kunth | CRXFR | CAFR3 | Cyperaceae |
| giant whitetop sedge | Rhynchospora latifolia (Baldw. ex Elliott) W. W. Thomas | DICLA | RHLA7 | Cyperaceae |
| globe sedge | Cyperus flavidus Retz. | Cyperaceae | ||
| green sedge | Cyperus virens Michx. | CYPVI | CYVI2 | Cyperaceae |
| hop sedge | Carex lupulina Muhl. ex Willd. | CRXLU | CALU4 | Cyperaceae |
| Japanese sedge | Carex kobomugi Ohwi | CRXKB | CAKO2 | Cyperaceae |
| knob sedge | Cyperus pseudovegetus Steud. | CYPPV | CYPS | Cyperaceae |
| lance sedge | Cyperus lanceolatus Poir. | CYPLC | CYLA5 | Cyperaceae |
| Leconte sedge | Cyperus lecontei Torr. ex Steud. | CYPLE | CYLE2 | Cyperaceae |
| longhair sedge | Carex comosa Boott | CRXCS | CACO8 | Cyperaceae |
| Louisiana sedge | Carex louisianica L. H. Bailey | CRXLN | CALO6 | Cyperaceae |
| lovegrass sedge | Cyperus eragrostis Lam. | CYPER | CYER | Cyperaceae |
| Nebraska sedge | Carex nebrascensis Dewey | CRXNB | CANE2 | Cyperaceae |
| nerved waxy sedge | Carex verrucosa Muhl. | CRXVR | CAVE8 | Cyperaceae |
| pale sedge | Carex pallescens L. | CRXPL | CAPA17 | Cyperaceae |
| pilose sedge | Cyperus pilosus L. | CYPPI | CYPI | Cyperaceae |
| sharpscale flatsedge | Cyperus oxylepis Ness ex Steud. | CYPOX | CYOX | Cyperaceae |
| prickly sedge | Carex spicata Huds. | CRXSP | CASP10 | Cyperaceae |
| Queensland sedge | Cyperus hyalinus Vahl | CYPHN | CYHY7 | Cyperaceae |
| remote sedge | Cyperus distans L. f. | CYPDT | CYDI7 | Cyperaceae |
| Rio Grande sedge | Cyperus floribundus (Kuk.) Carter & Jones | CYPFS | CYFL10 | Cyperaceae |
| ripgut sedge | Carex lacustris Willd. | CRXLA | CALA16 | Cyperaceae |
| rough sedge | Carex senta Boott | CRXSN | CASE | Cyperaceae |
| round sedge | Cyperus echinatus (L.) Alph. Wood | CYPEC | CYEC2 | Cyperaceae |
| smallflower umbrella sedge | Cyperus difformis L. | CYPDI | CYDI4 | Cyperaceae |
| smooth black sedge | Carex nigra (L.) Reichard | CRXNI | CANI5 | Cyperaceae |
| sugar grass sedge | Carex atherodes Spreng. | CRXAT | CAAT2 | Cyperaceae |
| Surinam sedge | Cyperus surinamensis Rottb. | CYPSU | CYSU | Cyperaceae |
| Texas sedge | Cyperus polystachyos Rottb. var. texensis (Torr.) Fernald | CYPPZ | CYPOT | Cyperaceae |
| water sedge | Carex aquatilis Wahlenb. | CRXAQ | CAAQ | Cyperaceae |
| waxy sedge | Carex glaucescens Elliott | CRXGL | CAGL5 | Cyperaceae |
| whitetop sedge | Rhynchospora colorata (L.) H. Pfeiffer | CYPKY | RHCO7 | Cyperaceae |
| widefruit sedge | Carex angustata Boott | CRXEU | CAAN15 | Cyperaceae |
| wolftail sedge | Carex cherokeensis Schwein. | CRXCH | CACH3 | Cyperaceae |
| woolfruit sedge | Carex lasiocarpa Ehrh. | CRXLC | CALA11 | Cyperaceae |
| yellowish sedge | Cyperus flavescens L. | CYPFC | CYFL | Cyperaceae |
| yellow white sedge | Carex albolutescens Schwein. | CRXAL | CAAL5 | Cyperaceae |
| alkali seepweed | Suaeda vera Forssk. ex J.F. Gmel. | SUEFR | SUVE2 | Chenopodiaceae |
| bush seepweed | Suaeda nigra (Raf.) J. F. Macbr. | SUENI | SUNI | Chenopodiaceae |
| western seepweed | Suaeda occidentalis (S. Watson) S. Watson | SUEOC | SUOC | Chenopodiaceae |
| seep willow | Baccharis salicifolia (Ruiz & Pav.) Pers. | BACSF | BASA4 | Asteraceae |
| coffee senna | Senna occidentalis (L.) Link | CASOC | SEOC2 | Fabaceae |
| sickle senna | Senna tora (L.) Roxb. | CASTO | SETO4 | Fabaceae |
| wild senna | Senna marilandica (L.) Link | CASMA | SEMA11 | Fabaceae |
| woolly senna | Senna hirsuta (L.) H. S. Irwin & Barneby var. glaberrima (M. E. Jones) H. S. Irwin & Barneby | SJNHG | SEHIG | Fabaceae |
| littleleaf sensitivebriar | Mimosa quadrivalvis L. var. angustata (Torr. & A. Gray) Barneby | SCNMI | MIQUA | Fabaceae |
| Nuttall sensitivebriar | Mimosa quadrivalvis L. var. nuttallii (DC. ex Britton & Rose) L. S. Beard ex Barneby | SCNNU | Fabaceae | |
| sensitiveplant | Mimosa pudica L. | MIMPU | MIPU8 | Fabaceae |
| giant sensitiveplant | Mimosa diplotricha C. Wright | MIMIN | MIDI8 | Fabaceae |
| serviceberry | Amelanchier alnifolia (Nutt.) Nutt. ex M. Roem. | AMEAL | AMAL2 | Rosaceae |
| Allegheny serviceberry | Amelanchier laevis Wiegand | AMELA | AMLA | Rosaceae |
| hemp sesbania | Sesbania herbacea (Mill.) McVaugh | SEBEX | SEHE8 | Fabaceae |
| red sesbania | Sesbania punicea (Cav.) Benth. | SEBPU | SEPU7 | Fabaceae |
| sewer vine | Paederia cruddasiana Prain | SENPN | PACR15 | Rubiaceae |
| smooth seymeria | Seymeria cassioides (J. F. Gmel.) S. F. Blake | SEYCA | SECA4 | Orobanchaceae |
| sticky seymeria | Seymeria pectinata Pursh | SEYPE | SEPE2 | Orobanchaceae |
| shadscale | Atriplex confertifolia (Torr. & Frém.) S. Watson | ATXCO | ATCO | Chenopodiaceae |
| shattercane | Sorghum bicolor (L.) Moench ssp. verticilliflorum (Steud.) de Wet ex Wiersema & J. Dahlb. | Poaceae | ||
| sheep laurel | Kalmia angustifolia L. | KAMAN | KAAN | Ericaceae |
| shepherds purse | Capsella bursa-pastoris (L.) Medik. | CAPBP | CABU2 | Brassicaceae |
| shinleaf | Pyrola americana Sweet | PYAM | Ericaceae | |
| shrimp plant | Justicia brandegeeana Wassh. & L. B. Sm. | BEOGU | JUBR6 | Acanthaceae |
| Jack in the bush | Chromolaena odorata (L.) R. M. King & H. Rob. | EUPOD | CHOD | Asteraceae |
| curved sicklegrass | Parapholis incurva (L.) C. E. Hubb. | PHOIN | PAIN | Poaceae |
| sicklepod | Senna obtusifolia (L.) H.S. Irwin & Barneby | CASOB | SEOB4 | Fabaceae |
| sickleweed | Falcaria vulgaris Bernh. | FALVU | FAVU | Apiaceae |
| arrowleaf sida | Sida rhombifolia L. | SIDRH | SIRH | Malvaceae |
| heartleaf sida | Sida cordifolia L. | SIDCO | SICO | Malvaceae |
| prickly sida | Sida spinosa L. | SIDSP | SISP | Malvaceae |
| southern sida | Sida acuta Burm. f. | SIDAC | SIAC3 | Malvaceae |
| broadleaf signalgrass | Urochloa platyphylla (Munro ex C. Wright) R.D. Webster | BRAPP | URPL2 | Poaceae |
| browntop signalgrass | Urochloa fusca (Sw.) B. F. Hansen & Wunderlin | URFU2 | Poaceae | |
| Dominican signalgrass | Urochloa adspersa (Trin.) R. Webster | PANAD | URAD | Poaceae |
| fringed signalgrass | Urochloa ciliatissima (Buckley) R. Webster | BRACI | URCI | Poaceae |
| narrowleaf signalgrass | Urochloa piligera (F. Muell. ex Benth.) R. Webster | BRAPI | URPI3 | Poaceae |
| silkgrass | Pityopsis graminifolia (Michx.) Nutt. | CYRGR | PIGR4 | Asteraceae |
| silktree | Albizia julibrissin Durazz. | ALBJU | ALJU | Fabaceae |
| Amur silvergrass | Miscanthus sacchariflorus (Maxim.) Franch. | MISSA | MISA | Poaceae |
| skeletonweed | Lygodesmia juncea (Pursh) D. Don ex Hook. | LYGJU | LYJU | Asteraceae |
| rush skeletonweed | Chondrilla juncea L. | CHOJU | CHJU | Asteraceae |
| hoary skullcap | Scutellaria incana Biehler | SCDIN | SCIN | Lamiaceae |
| marsh skullcap | Scutellaria galericulata L. | SCDGA | SCGA | Lamiaceae |
| skunkcabbage | Symplocarpus foetidus (L.) Salisb. ex W. P. C. Barton | SYLFO | SYFO | Araceae |
| skunk vine | Paederia foetida L. | PAEFO | PAFO3 | Rubiaceae |
| skunkweed | Navarretia squarrosa (Eschsch.) Hook. & Arn. | NAVSQ | NASQ | Polemoniaceae |
| claspingleaf smartweed | Persicaria perfoliata (L.) H. Gross | POLPF | PEPE35 | Polygonaceae |
| dotted smartweed | Polygonum punctatum Ell. | POLPT | POPU5 | Polygonaceae |
| hedge smartweed | Fallopia scandens (L.) Holub | POLSD | FASC | Polygonaceae |
| Himalayan smartweed | Persicaria capitata (Buch.-Ham. ex D. Don) H. Gross | POLCT | PECA29 | Polygonaceae |
| marshpepper smartweed | Persicaria hydropiper (L.) Delarbre | POLHY | PEHY6 | Polygonaceae |
| mild smartweed | Persicaria hydropiperoides (Michx.) Small | POLHP | PEHY7 | Polygonaceae |
| pale smartweed | Persicaria lapathifolia (L.) Delarbre | POLLA | PELA22 | Polygonaceae |
| Pennsylvania smartweed | Persicaria pensylvanica (L.) M. Gómez | POLPY | PEPE19 | Polygonaceae |
| prickly smartweed | Persicaria bungeana (Turcz.) Nakai | POLBU | PEBU3 | Polygonaceae |
| swamp smartweed | Persicaria amphibia (L.) Delarbre | POLAM | PEAM8 | Polygonaceae |
| smellmelon | Cucumis melo L. var. dudaim (L.) Naud. | CUMMD | CUMED | Cucurbitaceae |
| smilograss | Piptatherum miliaceum (L.) Coss. | ORZMI | PIMI3 | Poaceae |
| smut grass | Sporobolus indicus (L.) R. Br. | SPZIN | SPIN4 | Poaceae |
| button snakeroot | Eryngium yuccifolium Michx. | ERXYU | ERYU | Apiaceae |
| white snakeroot | Ageratina altissima (L.) R. M. King & H. Rob. | EUPRU | AGAL5 | Asteraceae |
| broom snakeweed | Gutierrezia sarothrae (Pursh) Britton & Rusby | GUESA | GUSA2 | Asteraceae |
| San Joaquin snakeweed | Gutierrezia californica (DC.) Torr. & A. Gray | GUCA | Asteraceae | |
| threadleaf snakeweed | Gutierrezia microcephala (DC.) A. Gray | GUEMI | GUMI | Asteraceae |
| snapdragon | Antirrhinum majus L. | ATHMM | ANMA3 | Plantaginaceae |
| dwarf snapdragon | Chaenorhinum minus (L.) Lange | CHNMI | CHMI | Plantaginaceae |
| linearleaf snapdragon | Misopates orontium (L.) Raf. | ATHOR | MIOR | Plantaginaceae |
| Bigelow sneezeweed | Helenium bigelovii A. Gray | HENBI | HEBI | Asteraceae |
| bitter sneezeweed | Helenium amarum (Raf.) H. Rock | HENAM | HEAM | Asteraceae |
| common sneezeweed | Helenium autumnale L. | HENAU | HEAU | Asteraceae |
| orange sneezeweed | Hymenoxys hoopesii (A. Gray) Bierner | HYXHO | HYHO | Asteraceae |
| purplehead sneezeweed | Helenium flexuosum Raf. | HENFL | HEFL | Asteraceae |
| common snowberry | Symphoricarpos albus (L.) S. F. Blake | SYPAL | SYAL | Caprifoliaceae |
| mountain snowberry | Symphoricarpos rotundifolius A. Gray | SYPRO | SYRO | Caprifoliaceae |
| trailing snowberry | Symphoricarpos mollis Nutt. | SYPMO | SYMO | Caprifoliaceae |
| western snowberry | Symphoricarpos occidentalis Hook. | SYPOC | SYOC | Caprifoliaceae |
| snowbrush ceanothus | Ceanothus velutinus Douglas | CEAVT | CEVE | Rhamnaceae |
| summer snowflake | Leucojum aestivum L. | LEJAE | LEAE | Amaryllidaceae |
| snow on the mountain | Euphorbia marginata Pursh | EPHMG | EUMA8 | Euphorbiaceae |
| soapberry | Sapindus saponaria L. | SAKSA | SASA4 | Sapindaceae |
| western soapberry | Sapindus saponaria L. var. drummondii (Hook. & Arn.) L. D. Benson | SAKSD | SASAD | Sapindaceae |
| wavyleaf soap plant | Chlorogalum pomeridianum (DC.) Kunth | CHLPO | CHPO3 | Asparagaceae |
| red soda apple | Solanum capsicoides All. | SOLCI | SOCA10 | Solanaceae |
| tropical soda apple | Solanum viarum Dunal | SOLVI | SOVI2 | Solanaceae |
| American Solomon's seal | Polygonatum biflorum (Walter) Elliott | PGBTI | POBI2 | Asparagaceae |
| silky sophora | Sophora nuttalliana B.L. Turner | SOBSR | SONU | Fabaceae |
| sorghum | Sorghum bicolor (L.) Moench ssp. bicolor | SORVU | SOBIB | Poaceae |
| sorghum almum | Sorghum x almum Parodi | SORAL | SOAL | Poaceae |
| green sorrel | Rumex acetosa L. | RUMAC | RUAC2 | Polygonaceae |
| heartwing sorrel | Rumex hastatulus Baldwin | RUMHA | RUHA2 | Polygonaceae |
| red sorrel | Rumex acetosella L. | RUMAA | RUAC3 | Polygonaceae |
| sourgrass | Digitaria insularis (L.) Mez ex Ekman | TRCIN | DIIN2 | Poaceae |
| annual sowthistle | Sonchus oleraceus L. | SONOL | SOOL | Asteraceae |
| marsh sowthistle | Sonchus arvensis L. ssp. uliginosus (M. Bieb.) Nyman | SONAU | SOARU | Asteraceae |
| perennial sowthistle | Sonchus arvensis L. | SONAR | SOAR2 | Asteraceae |
| spiny sowthistle | Sonchus asper (L.) Hill | SONAS | SOAS | Asteraceae |
| swamp sowthistle | Sonchus palustris L. | SONPA | SOPA10 | Asteraceae |
| soybean | Glycine max (L.) Merr. | GLXMA | GLMA4 | Fabaceae |
| Spanish needles | Bidens bipinnata L. | BIDBI | BIBI7 | Asteraceae |
| spatterdock | Nuphar advena (Aiton) W. T. Aiton | NUPLM | NUAD2 | Nymphaeaceae |
| spearmint | Mentha spicata L. | MENSP | MESP3 | Lamiaceae |
| spectacle fruit | Wislizenia refracta Engelm. | WISRE | WIRE | Cleomaceae |
| bilobed speedwell | Veronica biloba L. | VERBI | VEBI2 | Plantaginaceae |
| common speedwell | Veronica officinalis L. | VEROF | VEOF2 | Plantaginaceae |
| corn speedwell | Veronica arvensis L. | VERAR | VEAR | Plantaginaceae |
| field speedwell | Veronica agrestis L. | VERAG | VEAG | Plantaginaceae |
| germander speedwell | Veronica chamaedrys L. | VERCH | VECH | Plantaginaceae |
| ivyleaf speedwell | Veronica hederifolia L. | VERHE | VEHE2 | Plantaginaceae |
| longleaf speedwell | Veronica longifolia L. | VERLO | VELO2 | Plantaginaceae |
| Persian speedwell | Veronica persica Poir. | VERPE | VEPE3 | Plantaginaceae |
| purslane speedwell | Veronica peregrina L. | VERPG | VEPE2 | Plantaginaceae |
| slender speedwell | Veronica filiformis Sm. | VERFI | VEFI | Plantaginaceae |
| thymeleaf speedwell | Veronica serpyllifolia L. | VERSE | VESE | Plantaginaceae |
| water speedwell | Veronica anagallis-aquatica L. | VERAA | VEAN2 | Plantaginaceae |
| wayside speedwell | Veronica polita Fr. | VERPO | VEPO | Plantaginaceae |
| western purslane speedwell | Veronica peregrina L. ssp. xalapensis (Kunth) Pennell | VERPX | VEPEX2 | Plantaginaceae |
| spiderflower | Cleome hassleriana Chod. | CLEHA | CLHA | Cleomaceae |
| African spiderflower | Cleome gynandra L. | GYAGY | CLGY | Cleomaceae |
| red spiderlily | Lycoris radiata (L'Hér.) Herb. | LYRRA | LYRA | Amaryllidaceae |
| Coulter spiderling | Boerhavia coulteri (Hook. f.) S. Watson | BOECO | BOCO2 | Nyctaginaceae |
| erect spiderling | Boerhavia erecta L. | BOEER | BOER | Nyctaginaceae |
| red spiderling | Boerhavia diffusa L. | BOEDI | BODI3 | Nyctaginaceae |
| scarlet spiderling | Boerhavia coccinea Mill. | BOECC | BOCO | Nyctaginaceae |
| common spiderwort | Tradescantia ohiensis Raf. | TRAOH | TROH | Commelinaceae |
| longbract spiderwort | Tradescantia bracteata Small | TRABR | TRBR | Commelinaceae |
| white-flowered spiderwort | Tradescantia albiflora Kunth | TRAAL | TRAL9 | Commelinaceae |
| wild spikenard | Mesosphaerum suaveolens (L.) Kuntze | HPYSU | MESU17 | Lamiaceae |
| beaked spikerush | Eleocharis rostellata (Torr.) Torr. | ELORO | ELRO2 | Cyperaceae |
| blunt spikerush | Eleocharis obtusa (Willd.) Schult. | ELOOB | ELOB2 | Cyperaceae |
| creeping spikerush | Eleocharis palustris (L.) Roem. & Schult. | ELOPA | ELPA3 | Cyperaceae |
| dwarf spikerush | Eleocharis parvula (Roem. & Schult.) Link ex Buff, Nees & Sauer | ELOPV | ELPA5 | Cyperaceae |
| gulfcoast spikerush | Eleocharis cellulosa Torr. | ELOCE | ELCE | Cyperaceae |
| Montevidean spikerush | Eleocharis montevidensis Kunth | ELOMV | ELMO2 | Cyperaceae |
| needle spikerush | Eleocharis acicularis (L.) Roem. & Schult. | ELOAC | ELAC | Cyperaceae |
| pale spikerush | Eleocharis macrostachya Britton | ELOMS | ELMA5 | Cyperaceae |
| slender spikerush | Eleocharis baldwinii (Torr.) Chapm. | ELOBA | ELBA2 | Cyperaceae |
| sprouting spikerush | Eleocharis vivipara Link | ELOVI | ELVI4 | Cyperaceae |
| squarestem spikerush | Eleocharis quadrangulata (Michx.) Roem. & Schult. | ELOQU | ELQU | Cyperaceae |
| clustered spikeweed | Hemizonia fasciculata (DC.) Torr. & A. Gray | HEZFA | HEFA | Asteraceae |
| common spikeweed | Centromadia pungens (Hook. & Arn.) Greene | HEZPU | CEPUP6 | Asteraceae |
| New Zealand spinach | Tetragonia tetragonioides (Pall.) Kuntze | TEATE | TETE3 | Aizoaceae |
| spinystar | Escobaria vivipara (Nutt.) Buxb. | MAKVI | ESVI2 | Cactaceae |
| sponge plant | Limnobium laevigatum (Humb. & Bonpl. ex Willd.) Heine | LIMLA | LILA7 | Hydrocharitaceae |
| spoonflower | Peltandra sagittifolia (Michx.) Morong | PETSA | PESA7 | Araceae |
| Amazon sprangletop | Diplachne panicoides (J. Presl) McNeill | LEFPA | DIPA13 | Poaceae |
| bearded sprangletop | Diplachne fusca (L.) P. Beauv. ex Roem. & Schult. ssp. fascicularis (Lam.) P. M. Peterson & N. Snow | LEFFA | Poaceae | |
| Chinese sprangletop | Dinebra chinensis (L.) P. M. Peterson & N. Snow | LEFCH | LECH2 | Poaceae |
| green sprangletop | Diplachne dubia (Kunth) Scribn. | LEFDU | DIDU | Poaceae |
| Mexican sprangletop | Diplachne fusca (L.) P. Beauv. ex Roem. & Schult. ssp. uninervia (J. Presl) P. M. Peterson & N. Snow | LEFUN | Poaceae | |
| Nealley sprangletop | Leptochloa nealleyi Vasey | LENE2 | Poaceae | |
| red sprangletop | Dinebra panicea (Retz.) P. M. Peterson & N. Snow | LEFPC | LEPA6 | Poaceae |
| broadleaf spring-beauty | Claytonia caroliniana Michx. | CLACA | CLCA | Montiaceae |
| narrowleaf springbeauty | Claytonia virginica L. | CLAVI | CLVI3 | Montiaceae |
| serpentine springbeauty | Claytonia exigua Torr. & Gray | CLAEX | CLEX2 | Montiaceae |
| springparsley | Cymopterus ibapensis M. E. Jones | CYFWA | CYIB | Apiaceae |
| springstar | Tristagma uniflorum (Lindl.) Traub | IPHUN | TRUN6 | Amaryllidaceae |
| springtape | Sagittaria kurziana Glück | SAGSK | SAKU | Alismataceae |
| white spruce | Picea glauca (Moench) Voss | PIEGA | PIGL | Pinaceae |
| broad spurge | Euphorbia platyphyllos L. | EPHPL | EUPL | Euphorbiaceae |
| caper spurge | Euphorbia lathyris L. | EPHLA | EULA4 | Euphorbiaceae |
| creeping spurge | Euphorbia serpens Kunth | EPHSN | EUSE4 | Euphorbiaceae |
| cypress spurge | Euphorbia cyparissias L. | EPHCY | EUCY2 | Euphorbiaceae |
| flowering spurge | Euphorbia corollata L. | EPHCO | EUCO10 | Euphorbiaceae |
| garden spurge | Euphorbia hirta L. | EPHHI | EUHI | Euphorbiaceae |
| ground spurge | Euphorbia humistrata Engelm. | EPHHT | EUHU3 | Euphorbiaceae |
| hairy spurge | Euphorbia vermiculata Raf. | EPHVE | EUVE | Euphorbiaceae |
| hyssop spurge | Euphorbia hyssopifolia L. | EPHHS | EUHY2 | Euphorbiaceae |
| leafy spurge | Euphorbia esula L. | EPHES | EUES | Euphorbiaceae |
| littleleaf spurge | Euphorbia micromera Boiss. ex Engelm. | EPHMI | EUMI3 | Euphorbiaceae |
| myrtle spurge | Euphorbia myrsinites L. | EPHMY | EUMY2 | Euphorbiaceae |
| netseed spurge | Euphorbia spathulata Lam. | EPHSQ | EUSP | Euphorbiaceae |
| nodding spurge | Euphorbia nutans Lag. | EPHNU | EUNU | Euphorbiaceae |
| oblong spurge | Euphorbia oblongata Griseb. | EPHOB | EUOB4 | Euphorbiaceae |
| petty spurge | Euphorbia peplus L. | EPHPE | EUPE6 | Euphorbiaceae |
| prostrate spurge | Euphorbia prostrata Ait. | EPHPT | EUPR3 | Euphorbiaceae |
| ridgeseed spurge | Euphorbia glyptosperma Engelm. | EPHGL | EUGL3 | Euphorbiaceae |
| serrate spurge | Euphorbia serrata L. | EPHSR | EUSE12 | Euphorbiaceae |
| spotted spurge | Euphorbia maculata L. | EPHMA | EUMA7 | Euphorbiaceae |
| sun spurge | Euphorbia helioscopia L. | EPHHE | EUHE2 | Euphorbiaceae |
| thymeleaf spurge | Euphorbia serpyllifolia Pers. | EPHSP | EUSE5 | Euphorbiaceae |
| toothed spurge | Euphorbia dentata Michx. | EPHDE | EUDE4 | Euphorbiaceae |
| tree spurge | Euphorbia dendroides L. | EPHDN | EUDE10 | Euphorbiaceae |
| white margin spurge | Euphorbia albomarginata Torr. & A. Gray | EPHAL | EUAL4 | Euphorbiaceae |
| corn spurry | Spergula arvensis L. | SPRAR | SPAR | Caryophyllaceae |
| umbrella spurry | Holosteum umbellatum L. | HLOUM | HOUM | Caryophyllaceae |
| squirreltail | Elymus elymoides (Raf.) Swezey | SITHY | ELEL5 | Poaceae |
| big squirreltail | Elymus multisetus (J.G. Sm.) Burtt Davy | ELYMU | ELMU3 | Poaceae |
| St. Augustine grass | Stenotaphrum secundatum (Walter) Kuntze | STPSE | STSE | Poaceae |
| Canada St. Johnswort | Hypericum canadense L. | HYPCD | HYCA7 | Hypericaceae |
| common St. Johnswort | Hypericum perforatum L. | HYPPE | HYPE |