| Abdra brachycarpa | Greene | Brassicaceae | 8 |
| Acaciella angustissima | (Mill.) Britton & Rose | Fabaceae | 8 |
| Acalypha deamii | (Weath.) H.E.Ahles | Euphorbiaceae | 8 |
| Acalypha gracilens | A.Gray | Euphorbiaceae | 8 |
| Acalypha monococca | (Engelm. ex A.Gray) Lill.W.Mill. & Gandhi | Euphorbiaceae | 8 |
| Acalypha persimilis | Müll.Arg. | Euphorbiaceae | 8 |
| Acalypha rhomboidea | Raf. | Euphorbiaceae | 8 |
| Acalypha virginica | L. | Euphorbiaceae | 8 |
| Acer negundo | L. | Sapindaceae | 8 |
| Acer rubrum | L. | Sapindaceae | 8 |
| Acer saccharinum | L. | Sapindaceae | 8 |
| Acer saccharum | Marshall | Sapindaceae | 8 |
| Acmella repens | Rich. ex Pers. | Asteraceae | 8 |
| Acmispon americanus | (Nutt.) Rydb. | Fabaceae | 8 |
| Actaea pachypoda | Elliott | Ranunculaceae | 8 |
| Actaea racemosa | L. | Ranunculaceae | 8 |
| Adiantum capillus-veneris | L. | Pteridaceae | 8 |
| Adiantum pedatum | L. | Pteridaceae | 8 |
| Aesculus glabra | Willd. | Sapindaceae | 8 |
| Aesculus pavia | L. | Sapindaceae | 8 |
| Agalinis aspera | (Douglas ex Benth.) Britton | Orobanchaceae | 8 |
| Agalinis auriculata | (Michx.) S.F.Blake | Orobanchaceae | 8 |
| Agalinis fasciculata | (Elliott) Raf. | Orobanchaceae | 8 |
| Agalinis gattingeri | (Small) Small ex Britton & A.Br. | Orobanchaceae | 8 |
| Agalinis heterophylla | (Nutt.) Small ex Britton | Orobanchaceae | 8 |
| Agalinis purpurea | (L.) Pennell | Orobanchaceae | 8 |
| Agalinis tenuifolia | (Vahl) Raf. | Orobanchaceae | 8 |
| Agalinis viridis | (Small) Pennell | Orobanchaceae | 8 |
| Agastache nepetoides | (L.) Kuntze | Lamiaceae | 8 |
| Agastache scrophulariifolia | (Willd.) Kuntze | Lamiaceae | 8 |
| Agave virginica | L. | Asparagaceae | 8 |
| Ageratina altissima | (L.) R.M.King & H.Rob. | Asteraceae | 8 |
| Agrimonia gryposepala | Wallr. | Rosaceae | 8 |
| Agrimonia parviflora | Aiton | Rosaceae | 8 |
| Agrimonia pubescens | Wallr. | Rosaceae | 8 |
| Agrimonia rostellata | Wallr. | Rosaceae | 8 |
| Agrostis hyemalis | (Walter) Britton, Sterns & Poggenb. | Poaceae | 8 |
| Agrostis perennans | (Walter) Tuck. | Poaceae | 8 |
| Alisma subcordatum | Raf. | Alismataceae | 8 |
| Allium canadense | L. | Amaryllidaceae | 8 |
| Allium cernuum | Roth | Amaryllidaceae | 8 |
| Allium stellatum | Nutt. ex Ker Gawl. | Amaryllidaceae | 8 |
| Allium tricoccum | Aiton | Amaryllidaceae | 8 |
| Alnus serrulata | (Aiton) Willd. | Betulaceae | 8 |
| Alopecurus aequalis | Sobol. | Poaceae | 8 |
| Alopecurus carolinianus | Walter | Poaceae | 8 |
| Amaranthus blitoides | S.Watson | Amaranthaceae | 8 |
| Amaranthus hypochondriacus | L. | Amaranthaceae | 8 |
| Amaranthus tuberculatus | (Moq.) J.D.Sauer | Amaranthaceae | 8 |
| Ambrosia acanthicarpa | Hook. | Asteraceae | 8 |
| Ambrosia artemisiifolia | L. | Asteraceae | 8 |
| Ambrosia bidentata | Michx. | Asteraceae | 8 |
| Ambrosia psilostachya | DC. | Asteraceae | 8 |
| Ambrosia trifida | L. | Asteraceae | 8 |
| Amelanchier arborea | (F.Michx.) Fernald | Rosaceae | 8 |
| Amelanchier humilis | Wiegand | Rosaceae | 8 |
| Ammannia coccinea | Rottb. | Lythraceae | 8 |
| Ammannia robusta | Heer & Regel | Lythraceae | 8 |
| Ammoselinum butleri | (Engelm. ex S.Watson) J.M.Coult. & Rose | Apiaceae | 8 |
| Amorpha canescens | Pursh | Fabaceae | 8 |
| Ampelopsis cordata | Michx. | Vitaceae | 8 |
| Amphicarpaea bracteata | (L.) Fernald | Fabaceae | 8 |
| Amsinckia tessellata | A.Gray | Boraginaceae | 8 |
| Amsonia ciliata | Walter | Apocynaceae | 8 |
| Amsonia tabernaemontana | Walter | Apocynaceae | 8 |
| Andersonglossum virginianum | (L.) J.I.Cohen | Boraginaceae | 8 |
| Andropogon virginicus | L. | Poaceae | 8 |
| Androsace occidentalis | Pursh | Primulaceae | 8 |
| Anemonastrum canadense | (L.) Mosyakin | Ranunculaceae | 8 |
| Anemone caroliniana | Walter | Ranunculaceae | 8 |
| Anemone cylindrica | A.Gray | Ranunculaceae | 8 |
| Anemone quinquefolia | L. | Ranunculaceae | 8 |
| Anemone virginiana | L. | Ranunculaceae | 8 |
| Anemonella thalictroides | Spach | Ranunculaceae | 8 |
| Angelica venenosa | (J.Greenway) Fernald | Apiaceae | 8 |
| Antennaria neglecta | Greene | Asteraceae | 8 |
| Antennaria parlinii | Fernald | Asteraceae | 8 |
| Antennaria plantaginifolia | (L.) Richardson | Asteraceae | 8 |
| Anticlea elegans | (Pursh) Rydb. | Melanthiaceae | 8 |
| Apios americana | Medik. | Fabaceae | 8 |
| Aplectrum hyemale | (Muhl. ex Willd.) Torr. | Orchidaceae | 8 |
| Apocynum androsaemifolium | L. | Apocynaceae | 8 |
| Apocynum cannabinum | L. | Apocynaceae | 8 |
| Aquarius cordifolius | (L.) Christenh. & Byng | Alismataceae | 8 |
| Aquilegia canadensis | L. | Ranunculaceae | 8 |
| Arabidopsis lyrata | (L.) O'Kane & Al-Shehbaz | Brassicaceae | 8 |
| Aralia nudicaulis | L. | Araliaceae | 8 |
| Aralia racemosa | L. | Araliaceae | 8 |
| Aralia spinosa | L. | Araliaceae | 8 |
| Argyrochosma dealbata | (Pursh) Windham | Pteridaceae | 8 |
| Arisaema dracontium | (L.) Schott | Araceae | 8 |
| Arisaema triphyllum | (L.) Schott | Araceae | 8 |
| Aristida desmantha | Trin. & Rupr. | Poaceae | 8 |
| Aristida lanosa | Muhl. ex Elliott | Poaceae | 8 |
| Aristida longespica | Poir. | Poaceae | 8 |
| Aristida oligantha | Michx. | Poaceae | 8 |
| Aristida purpurascens | Poir. | Poaceae | 8 |
| Aristolochia serpentaria | L. | Aristolochiaceae | 8 |
| Aristolochia tomentosa | Sims | Aristolochiaceae | 8 |
| Arnoglossum atriplicifolium | (L.) H.Rob. | Asteraceae | 8 |
| Arnoglossum plantagineum | Raf. | Asteraceae | 8 |
| Arnoglossum reniforme | (Hook.) H.Rob. | Asteraceae | 8 |
| Aronia melanocarpa | (Michx.) Elliott | Rosaceae | 8 |
| Artemisia campestris | L. | Asteraceae | 8 |
| Artemisia carruthii | Alph.Wood ex J.H.Carruth | Asteraceae | 8 |
| Artemisia dracunculus | L. | Asteraceae | 8 |
| Artemisia ludoviciana | Nutt. | Asteraceae | 8 |
| Aruncus dioicus | (Walter) Fernald | Rosaceae | 8 |
| Arundinaria gigantea | (Walter) Muhl. | Poaceae | 8 |
| Asarum canadense | L. | Aristolochiaceae | 8 |
| Asarum reflexum | E.P.Bicknell | Aristolochiaceae | 8 |
| Asclepias amplexicaulis | Sm. | Apocynaceae | 8 |
| Asclepias exaltata | L. | Apocynaceae | 8 |
| Asclepias hirtella | (Pennell) Woodson | Apocynaceae | 8 |
| Asclepias incarnata | L. | Apocynaceae | 8 |
| Asclepias meadii | Torr. ex A.Gray | Apocynaceae | 8 |
| Asclepias perennis | Walter | Apocynaceae | 8 |
| Asclepias purpurascens | L. | Apocynaceae | 8 |
| Asclepias quadrifolia | Jacq. | Apocynaceae | 8 |
| Asclepias stenophylla | A.Gray | Apocynaceae | 8 |
| Asclepias subverticillata | (A.Gray) Vail | Apocynaceae | 8 |
| Asclepias sullivantii | Engelm. ex A.Gray | Apocynaceae | 8 |
| Asclepias syriaca | L. | Apocynaceae | 8 |
| Asclepias tuberosa | L. | Apocynaceae | 8 |
| Asclepias variegata | L. | Apocynaceae | 8 |
| Asclepias verticillata | L. | Apocynaceae | 8 |
| Asclepias viridiflora | Raf. | Apocynaceae | 8 |
| Asclepias viridis | Walter | Apocynaceae | 8 |
| Asimina triloba | (L.) Dunal | Annonaceae | 8 |
| Asplenium bradleyi | D.C.Eaton | Aspleniaceae | 8 |
| Asplenium montanum | Willd. | Aspleniaceae | 8 |
| Asplenium pinnatifidum | Nutt. | Aspleniaceae | 8 |
| Asplenium platyneuron | (L.) Britton, Sterns & Poggenb. | Aspleniaceae | 8 |
| Asplenium resiliens | Kunze | Aspleniaceae | 8 |
| Asplenium rhizophyllum | L. | Aspleniaceae | 8 |
| Asplenium ruta-muraria | L. | Aspleniaceae | 8 |
| Asplenium trichomanes | L. | Aspleniaceae | 8 |
| Astragalus canadensis | L. | Fabaceae | 8 |
| Astragalus crassicarpus | Nutt. | Fabaceae | 8 |
| Astragalus distortus | Torr. & A.Gray | Fabaceae | 8 |
| Astragalus lotiflorus | Hook. | Fabaceae | 8 |
| Astranthium ciliatum | (Raf.) G.L.Nesom | Asteraceae | 8 |
| Athyrium angustum | (Willd.) C.Presl | Athyriaceae | 8 |
| Athyrium asplenioides | (Michx.) Desv. | Athyriaceae | 8 |
| Atriplex patula | L. | Chenopodiaceae | 8 |
| Aureolaria flava | (L.) Farw. | Orobanchaceae | 8 |
| Aureolaria grandiflora | (Benth.) Pennell | Orobanchaceae | 8 |
| Aureolaria pectinata | (Nutt.) Pennell | Orobanchaceae | 8 |
| Aureolaria pedicularia | (L.) Raf. ex Farw. | Orobanchaceae | 8 |
| Avenella flexuosa | (L.) Drejer | Poaceae | 8 |
| Azolla caroliniana | Willd. | Salviniaceae | 8 |
| Azolla filiculoides | Lam. | Salviniaceae | 8 |
| Baptisia australis | (L.) R.Br. | Fabaceae | 8 |
| Baptisia lactea | (Raf.) Thieret | Fabaceae | 8 |
| Baptisia leucophaea | Nutt. | Fabaceae | 8 |
| Baptisia sphaerocarpa | Nutt. | Fabaceae | 8 |
| Bartonia paniculata | (Michx.) Muhl. | Gentianaceae | 8 |
| Beckmannia syzigachne | (Steud.) Fernald | Poaceae | 8 |
| Berberis canadensis | Mill. | Berberidaceae | 8 |
| Berchemia scandens | (Hill) K.Koch | Rhamnaceae | 8 |
| Berlandiera texana | DC. | Asteraceae | 8 |
| Berula erecta | (Huds.) Coville | Apiaceae | 8 |
| Betula nigra | L. | Betulaceae | 8 |
| Bidens alba | DC. | Asteraceae | 8 |
| Bidens aristosa | Britton | Asteraceae | 8 |
| Bidens beckii | Torr. ex Spreng. | Asteraceae | 8 |
| Bidens bipinnata | L. | Asteraceae | 8 |
| Bidens cernua | L. | Asteraceae | 8 |
| Bidens connata | Muhl. ex Willd. | Asteraceae | 8 |
| Bidens discoidea | Britton | Asteraceae | 8 |
| Bidens frondosa | L. | Asteraceae | 8 |
| Bidens laevis | (L.) Britton, Sterns & Poggenb. | Asteraceae | 8 |
| Bidens mitis | Sherff | Asteraceae | 8 |
| Bidens polylepis | S.F.Blake | Asteraceae | 8 |
| Bidens trichosperma | (Michx.) Britton | Asteraceae | 8 |
| Bidens tripartita | L. | Asteraceae | 8 |
| Bidens vulgata | Greene | Asteraceae | 8 |
| Bignonia capreolata | L. | Bignoniaceae | 8 |
| Blephilia ciliata | (L.) Raf. ex Benth. | Lamiaceae | 8 |
| Blephilia hirsuta | (Pursh) Benth. | Lamiaceae | 8 |
| Bletia spicata | (Walter) Sosa & M.W.Chase | Orchidaceae | 8 |
| Blitum capitatum | L. | Chenopodiaceae | 8 |
| Boehmeria cylindrica | (L.) Sw. | Urticaceae | 8 |
| Bolboschoenus fluviatilis | (Torr.) Soják | Cyperaceae | 8 |
| Bolboschoenus maritimus | (L.) Palla | Cyperaceae | 8 |
| Boltonia asteroides | L'Hér. | Asteraceae | 8 |
| Boltonia decurrens | (Torr. & A.Gray) Wood | Asteraceae | 8 |
| Boltonia diffusa | Elliott | Asteraceae | 8 |
| Borodinia canadensis | (L.) P.J.Alexander & Windham | Brassicaceae | 8 |
| Borodinia dentata | (Raf.) P.J.Alexander & Windham | Brassicaceae | 8 |
| Borodinia laevigata | (Muhl. ex Willd.) P.J.Alexander & Windham | Brassicaceae | 8 |
| Borodinia missouriensis | (Greene) P.J.Alexander & Windham | Brassicaceae | 8 |
| Bothriochloa barbinodis | (Lag.) Herter | Poaceae | 8 |
| Bothriochloa torreyana | (Steud.) Scrivanti & Anton | Poaceae | 8 |
| Botrypus virginianus | (L.) Michx. | Ophioglossaceae | 8 |
| Bouteloua curtipendula | (Michx.) Torr. | Poaceae | 8 |
| Bouteloua dactyloides | (Nutt.) Columbus | Poaceae | 8 |
| Bouteloua gracilis | (Kunth) Lag. ex Griffiths | Poaceae | 8 |
| Bouteloua hirsuta | Lag. | Poaceae | 8 |
| Brachyelytrum erectum | (Schreb.) P.Beauv. | Poaceae | 8 |
| Bradburia pilosa | (Nutt.) Semple | Asteraceae | 8 |
| Brasenia schreberi | J.F.Gmel. | Cabombaceae | 8 |
| Brickellia eupatorioides | (L.) Shinners | Asteraceae | 8 |
| Brickellia grandiflora | Nutt. | Asteraceae | 8 |
| Bromus latiglumis | (Shear) Hitchc. | Poaceae | 8 |
| Bromus nottowayanus | Fernald | Poaceae | 8 |
| Bromus pubescens | Muhl. ex Willd. | Poaceae | 8 |
| Brunnichia ovata | (Walter) Shinners | Polygonaceae | 8 |
| Buchnera americana | L. | Orobanchaceae | 8 |
| Bulbostylis capillaris | (L.) Kunth ex C.B.Clarke | Cyperaceae | 8 |
| Cabomba caroliniana | A.Gray | Cabombaceae | 8 |
| Calamagrostis canadensis | (Michx.) P.Beauv. | Poaceae | 8 |
| Calamagrostis inexpansa | A.Gray | Poaceae | 8 |
| Calamagrostis stricta | (Timm) Koeler | Poaceae | 8 |
| Callicarpa americana | L. | Lamiaceae | 8 |
| Callirhoe alcaeoides | (Michx.) A.Gray | Malvaceae | 8 |
| Callirhoe digitata | Nutt. | Malvaceae | 8 |
| Callirhoe involucrata | (Torr. & A.Gray) A.Gray | Malvaceae | 8 |
| Callirhoe triangulata | (Leavenw.) A.Gray | Malvaceae | 8 |
| Callitriche heterophylla | Pursh | Plantaginaceae | 8 |
| Callitriche palustris | L. | Plantaginaceae | 8 |
| Callitriche terrestris | Raf. | Plantaginaceae | 8 |
| Calopogon oklahomensis | D.H.Goldman | Orchidaceae | 8 |
| Calopogon tuberosus | (L.) Britton, Sterns & Poggenb. | Orchidaceae | 8 |
| Caltha palustris | L. | Ranunculaceae | 8 |
| Calycocarpum lyonii | (Pursh) Nutt. ex A.Gray | Menispermaceae | 8 |
| Calystegia sepium | (L.) R.Br. | Convolvulaceae | 8 |
| Calystegia silvatica | Griseb. | Convolvulaceae | 8 |
| Calystegia spithamaea | (L.) Pursh | Convolvulaceae | 8 |
| Camassia angusta | (Engelm. & A.Gray) Blank. | Asparagaceae | 8 |
| Camassia scilloides | (Raf.) Cory | Asparagaceae | 8 |
| Campanula americana | L. | Campanulaceae | 8 |
| Campanula intercedens | Witasek | Campanulaceae | 8 |
| Campsis radicans | (L.) Bureau | Bignoniaceae | 8 |
| Cardamine bulbosa | (Schreb. ex Muhl.) Britton, Sterns & Poggenb. | Brassicaceae | 8 |
| Cardamine concatenata | (Michx.) O.Schwarz | Brassicaceae | 8 |
| Cardamine douglassii | Britton | Brassicaceae | 8 |
| Cardamine parviflora | L. | Brassicaceae | 8 |
| Cardamine pensylvanica | Muhl. ex Willd. | Brassicaceae | 8 |
| Carex abscondita | Mack. | Cyperaceae | 8 |
| Carex aggregata | Mack. | Cyperaceae | 8 |
| Carex albicans | Willd. ex Spreng. | Cyperaceae | 8 |
| Carex albolutescens | Schwein. | Cyperaceae | 8 |
| Carex albursina | E.Sheld. | Cyperaceae | 8 |
| Carex amphibola | Steud. | Cyperaceae | 8 |
| Carex annectens | (E.P.Bicknell) E.P.Bicknell | Cyperaceae | 8 |
| Carex aquatilis | Wahlenb. | Cyperaceae | 8 |
| Carex atherodes | Spreng. | Cyperaceae | 8 |
| Carex atlantica | L.H.Bailey | Cyperaceae | 8 |
| Carex aureolensis | Steud. | Cyperaceae | 8 |
| Carex austrina | Mack. | Cyperaceae | 8 |
| Carex bicknellii | Britton & A.Br. | Cyperaceae | 8 |
| Carex blanda | Dewey | Cyperaceae | 8 |
| Carex brevior | (Dewey) Mack. ex Lunell | Cyperaceae | 8 |
| Carex bromoides | Willd. | Cyperaceae | 8 |
| Carex bushii | Mack. | Cyperaceae | 8 |
| Carex buxbaumii | Wahlenb. | Cyperaceae | 8 |
| Carex careyana | Torr. ex Dewey | Cyperaceae | 8 |
| Carex caroliniana | Schwein. | Cyperaceae | 8 |
| Carex cephalophora | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex cherokeensis | Schwein. | Cyperaceae | 8 |
| Carex communis | L.H.Bailey | Cyperaceae | 8 |
| Carex complanata | Torr. & Hook. | Cyperaceae | 8 |
| Carex conjuncta | Boott | Cyperaceae | 8 |
| Carex corrugata | Fernald | Cyperaceae | 8 |
| Carex crawei | Dewey ex Torr. | Cyperaceae | 8 |
| Carex crawfordii | Fernald | Cyperaceae | 8 |
| Carex crinita | Lam. | Cyperaceae | 8 |
| Carex cristatella | Britton | Cyperaceae | 8 |
| Carex crus-corvi | Shuttlew. ex Kunze | Cyperaceae | 8 |
| Carex davisii | Schwein. & Torr. | Cyperaceae | 8 |
| Carex debilis | Michx. | Cyperaceae | 8 |
| Carex decomposita | Muhl. | Cyperaceae | 8 |
| Carex digitalis | Willd. | Cyperaceae | 8 |
| Carex douglasii | Boott | Cyperaceae | 8 |
| Carex duriuscula | C.A.Mey. | Cyperaceae | 8 |
| Carex eburnea | Boott | Cyperaceae | 8 |
| Carex echinata | Murray | Cyperaceae | 8 |
| Carex emoryi | Dewey | Cyperaceae | 8 |
| Carex festucacea | Willd. | Cyperaceae | 8 |
| Carex flaccosperma | Dewey | Cyperaceae | 8 |
| Carex frankii | Kunth | Cyperaceae | 8 |
| Carex gigantea | Rudge | Cyperaceae | 8 |
| Carex glaucodea | Tuck. ex Olney | Cyperaceae | 8 |
| Carex gracilescens | Steud. | Cyperaceae | 8 |
| Carex gracillima | Schwein. | Cyperaceae | 8 |
| Carex granularis | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex gravida | L.H.Bailey | Cyperaceae | 8 |
| Carex grayi | J.Carey | Cyperaceae | 8 |
| Carex grisea | Wahlenb. | Cyperaceae | 8 |
| Carex haydenii | Dewey | Cyperaceae | 8 |
| Carex hirsutella | Mack. | Cyperaceae | 8 |
| Carex hirtifolia | Mack. | Cyperaceae | 8 |
| Carex hitchcockiana | Dewey | Cyperaceae | 8 |
| Carex hyalinolepis | Steud. | Cyperaceae | 8 |
| Carex hystericina | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex inops | L.H.Bailey | Cyperaceae | 8 |
| Carex interior | L.H.Bailey | Cyperaceae | 8 |
| Carex intumescens | Rudge | Cyperaceae | 8 |
| Carex jamesii | Schwein. | Cyperaceae | 8 |
| Carex joorii | L.H.Bailey | Cyperaceae | 8 |
| Carex lacustris | Willd. | Cyperaceae | 8 |
| Carex laevivaginata | (Kük.) Mack. | Cyperaceae | 8 |
| Carex laxiculmis | Schwein. | Cyperaceae | 8 |
| Carex laxiflora | Lam. | Cyperaceae | 8 |
| Carex leavenworthii | Dewey | Cyperaceae | 8 |
| Carex leptalea | Wahlenb. | Cyperaceae | 8 |
| Carex longii | Mack. | Cyperaceae | 8 |
| Carex louisianica | L.H.Bailey | Cyperaceae | 8 |
| Carex lupulina | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex lurida | Wahlenb. | Cyperaceae | 8 |
| Carex meadii | Dewey | Cyperaceae | 8 |
| Carex microdonta | Torr. | Cyperaceae | 8 |
| Carex molesta | Mack. | Cyperaceae | 8 |
| Carex muehlenbergii | Schkuhr ex Willd. | Cyperaceae | 8 |
| Carex muskingumensis | Schwein. | Cyperaceae | 8 |
| Carex nigromarginata | Schwein. | Cyperaceae | 8 |
| Carex normalis | Mack. | Cyperaceae | 8 |
| Carex oxylepis | Torr. & Hook. | Cyperaceae | 8 |
| Carex pellita | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex pensylvanica | Lam. | Cyperaceae | 8 |
| Carex planispicata | Naczi | Cyperaceae | 8 |
| Carex praegracilis | W.Boott | Cyperaceae | 8 |
| Carex prasina | Wahlenb. | Cyperaceae | 8 |
| Carex radiata | (Wahlenb.) Small | Cyperaceae | 8 |
| Carex retroflexa | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex rosea | Willd. | Cyperaceae | 8 |
| Carex sartwellii | Dewey | Cyperaceae | 8 |
| Carex scabrata | Schwein. | Cyperaceae | 8 |
| Carex scoparia | Schkuhr ex Willd. | Cyperaceae | 8 |
| Carex shortiana | Dewey & Torr. | Cyperaceae | 8 |
| Carex sparganioides | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex sprengelii | Dewey ex Spreng. | Cyperaceae | 8 |
| Carex squarrosa | L. | Cyperaceae | 8 |
| Carex sterilis | Willd. | Cyperaceae | 8 |
| Carex stipata | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex stricta | Lam. | Cyperaceae | 8 |
| Carex swanii | (Fernald) Mack. | Cyperaceae | 8 |
| Carex sychnocephala | J.Carey | Cyperaceae | 8 |
| Carex tenera | Dewey | Cyperaceae | 8 |
| Carex tetanica | Schkuhr | Cyperaceae | 8 |
| Carex texensis | (Torr. ex L.H.Bailey) L.H.Bailey | Cyperaceae | 8 |
| Carex torta | Boott ex Tuck. | Cyperaceae | 8 |
| Carex tribuloides | Wahlenb. | Cyperaceae | 8 |
| Carex trichocarpa | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex typhina | Michx. | Cyperaceae | 8 |
| Carex umbellata | Willd. | Cyperaceae | 8 |
| Carex virescens | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex vulpinoidea | Michx. | Cyperaceae | 8 |
| Carex willdenowii | Willd. | Cyperaceae | 8 |
| Carpinus caroliniana | Walter | Betulaceae | 8 |
| Carya aquatica | (F.Michx.) Nutt. ex Elliott | Juglandaceae | 8 |
| Carya cordiformis | (Wangenh.) K.Koch | Juglandaceae | 8 |
| Carya glabra | (Mill.) Sweet | Juglandaceae | 8 |
| Carya illinoinensis | (Wangenh.) K.Koch | Juglandaceae | 8 |
| Carya laciniosa | (F.Michx.) G.Don | Juglandaceae | 8 |
| Carya ovata | (Mill.) K.Koch | Juglandaceae | 8 |
| Carya pallida | (Ashe) Engelm. & Graebn. | Juglandaceae | 8 |
| Carya texana | Buckley | Juglandaceae | 8 |
| Carya tomentosa | (Lam.) Nutt. | Juglandaceae | 8 |
| Castanea dentata | Borkh. | Fagaceae | 8 |
| Castanea ozarkensis | Ashe | Fagaceae | 8 |
| Castanea pumila | (L.) Mill. | Fagaceae | 8 |
| Castilleja coccinea | (L.) Spreng. | Orobanchaceae | 8 |
| Castilleja purpurea | (Nutt.) G.Don | Orobanchaceae | 8 |
| Castilleja sessiliflora | Pursh | Orobanchaceae | 8 |
| Catalpa speciosa | (Warder) Engelm. | Bignoniaceae | 8 |
| Caulophyllum thalictroides | (L.) Michx. | Berberidaceae | 8 |
| Cayaponia quinqueloba | (Raf.) Shinners | Cucurbitaceae | 8 |
| Ceanothus americanus | L. | Rhamnaceae | 8 |
| Ceanothus herbaceus | Raf. | Rhamnaceae | 8 |
| Celastrus scandens | L. | Celastraceae | 8 |
| Celtis laevigata | Willd. | Cannabaceae | 8 |
| Celtis occidentalis | L. | Cannabaceae | 8 |
| Celtis tenuifolia | Nutt. | Cannabaceae | 8 |
| Cephalanthus occidentalis | L. | Rubiaceae | 8 |
| Cerastium brachypodum | (Engelm. ex A.Gray) B.L.Rob. | Caryophyllaceae | 8 |
| Cerastium nutans | Raf. | Caryophyllaceae | 8 |
| Cerastium velutinum | Raf. | Caryophyllaceae | 8 |
| Ceratophyllum demersum | L. | Ceratophyllaceae | 8 |
| Ceratophyllum echinatum | A.Gray | Ceratophyllaceae | 8 |
| Cercis canadensis | L. | Fabaceae | 8 |
| Chaerophyllum procumbens | (L.) Crantz | Apiaceae | 8 |
| Chaerophyllum tainturieri | Hook. | Apiaceae | 8 |
| Chaetopappa asteroides | (Nutt.) DC. | Asteraceae | 8 |
| Chamaecrista fasciculata | (Michx.) Greene | Fabaceae | 8 |
| Chamaecrista nictitans | (L.) Moench | Fabaceae | 8 |
| Chasmanthium latifolium | (Michx.) H.O.Yates | Poaceae | 8 |
| Chasmanthium laxum | (L.) H.O.Yates | Poaceae | 8 |
| Chelone glabra | L. | Plantaginaceae | 8 |
| Chenopodium berlandieri | Moq. | Chenopodiaceae | 8 |
| Chenopodium incanum | (S.Watson) A.Heller | Chenopodiaceae | 8 |
| Chenopodium rubrum | L. | Chenopodiaceae | 8 |
| Chionanthus virginicus | L. | Oleaceae | 8 |
| Chloris verticillata | Nutt. | Poaceae | 8 |
| Chloris virgata | Sw. | Poaceae | 8 |
| Cicuta maculata | L. | Apiaceae | 8 |
| Cinna arundinacea | L. | Poaceae | 8 |
| Circaea alpina | L. | Onagraceae | 8 |
| Circaea canadensis | (L.) Hill | Onagraceae | 8 |
| Cirsium altissimum | (L.) Hill | Asteraceae | 8 |
| Cirsium canescens | Nutt. | Asteraceae | 8 |
| Cirsium carolinianum | (Walter) Fernald & B.G.Schub. | Asteraceae | 8 |
| Cirsium discolor | (Muhl. ex Willd.) Spreng. | Asteraceae | 8 |
| Cirsium muticum | Michx. | Asteraceae | 8 |
| Cirsium texanum | Buckley | Asteraceae | 8 |
| Cirsium undulatum | (Nutt.) Spreng. | Asteraceae | 8 |
| Cissus trifoliata | (L.) L. | Vitaceae | 8 |
| Cladrastis kentukea | (Dum.Cours.) Rudd | Fabaceae | 8 |
| Claytonia virginica | L. | Montiaceae | 8 |
| Claytosmunda claytoniana | (L.) Metzgar & Rouhan | Osmundaceae | 8 |
| Clematis catesbyana | Pursh | Ranunculaceae | 8 |
| Clematis crispa | L. | Ranunculaceae | 8 |
| Clematis fremontii | S.Watson | Ranunculaceae | 8 |
| Clematis pitcheri | Torr. & A.Gray | Ranunculaceae | 8 |
| Clematis versicolor | Small ex Rydb. | Ranunculaceae | 8 |
| Clematis viorna | L. | Ranunculaceae | 8 |
| Clematis virginiana | L. | Ranunculaceae | 8 |
| Cleome dodecandra | L. | Cleomaceae | 8 |
| Cleomella serrulata | (Pursh) Roalson & J.C.Hall | Cleomaceae | 8 |
| Clinopodium arkansanum | (Nutt.) House | Lamiaceae | 8 |
| Coleataenia anceps | (Michx.) Soreng | Poaceae | 8 |
| Coleataenia rigidula | (Bosc ex Nees) LeBlond | Poaceae | 8 |
| Collinsia verna | Nutt. | Plantaginaceae | 8 |
| Collinsia violacea | Nutt. | Plantaginaceae | 8 |
| Collinsonia canadensis | L. | Lamiaceae | 8 |
| Collomia linearis | Nutt. | Polemoniaceae | 8 |
| Comandra umbellata | (L.) Nutt. | Santalaceae | 8 |
| Commelina erecta | L. | Commelinaceae | 8 |
| Commelina virginica | L. | Commelinaceae | 8 |
| Conioselinum chinense | (L.) Britton, Sterns & Poggenb. | Apiaceae | 8 |
| Conoclinium coelestinum | DC. | Asteraceae | 8 |
| Conyza ramosissima | Cronquist | Asteraceae | 8 |
| Corallorhiza odontorhiza | (Willd.) Nutt. | Orchidaceae | 8 |
| Corallorhiza wisteriana | Conrad | Orchidaceae | 8 |
| Coreopsis grandiflora | Hogg ex Sweet | Asteraceae | 8 |
| Coreopsis lanceolata | L. | Asteraceae | 8 |
| Coreopsis pubescens | Elliott | Asteraceae | 8 |
| Coreopsis tinctoria | Nutt. | Asteraceae | 8 |
| Coreopsis tripteris | L. | Asteraceae | 8 |
| Corispermum villosum | Rydb. | Chenopodiaceae | 8 |
| Cornus alternifolia | L.f. | Cornaceae | 8 |
| Cornus amomum | Mill. | Cornaceae | 8 |
| Cornus drummondii | C.A.Mey. | Cornaceae | 8 |
| Cornus florida | L. | Cornaceae | 8 |
| Cornus foemina | Mill. | Cornaceae | 8 |
| Cornus obliqua | Raf. | Cornaceae | 8 |
| Cornus racemosa | Lam. | Cornaceae | 8 |
| Corydalis aurea | Willd. | Papaveraceae | 8 |
| Corydalis flavula | (Raf.) DC. | Papaveraceae | 8 |
| Corydalis micrantha | (Engelm. ex A.Gray) A.Gray ex J.M.Coult. | Papaveraceae | 8 |
| Corylus americana | Walter | Betulaceae | 8 |
| Cotinus obovatus | Raf. | Anacardiaceae | 8 |
| Crataegus berberifolia | Torr. & A.Gray | Rosaceae | 8 |
| Crataegus chrysocarpa | Ashe | Rosaceae | 8 |
| Crataegus coccinioides | Ashe | Rosaceae | 8 |
| Crataegus crus-galli | L. | Rosaceae | 8 |
| Crataegus gattingeri | Ashe | Rosaceae | 8 |
| Crataegus intricata | Lange | Rosaceae | 8 |
| Crataegus macracantha | (Lindl.) Lodd. ex Loudon | Rosaceae | 8 |
| Crataegus mollis | (Torr. & A.Gray) Scheele | Rosaceae | 8 |
| Crataegus pruinosa | (H.L.Wendl.) K.Koch | Rosaceae | 8 |
| Crataegus punctata | Jacq. | Rosaceae | 8 |
| Crataegus schuettei | Ashe | Rosaceae | 8 |
| Crataegus spathulata | Michx. | Rosaceae | 8 |
| Crataegus uniflora | Münchh. | Rosaceae | 8 |
| Crataegus viridis | L. | Rosaceae | 8 |
| Crocanthemum bicknellii | (Fernald) Janch. | Cistaceae | 8 |
| Crocanthemum canadense | (L.) Britton | Cistaceae | 8 |
| Crotalaria sagittalis | L. | Fabaceae | 8 |
| Croton capitatus | Michx. | Euphorbiaceae | 8 |
| Croton glandulosus | L. | Euphorbiaceae | 8 |
| Croton lindheimeri | (Engelm. & A.Gray) Alph.Wood | Euphorbiaceae | 8 |
| Croton lindheimerianus | Scheele | Euphorbiaceae | 8 |
| Croton michauxii | G.L.Webster | Euphorbiaceae | 8 |
| Croton monanthogynus | Michx. | Euphorbiaceae | 8 |
| Croton texensis | (Klotzsch) Müll.Arg. | Euphorbiaceae | 8 |
| Cryptotaenia canadensis | (L.) DC. | Apiaceae | 8 |
| Cucurbita foetidissima | Kunth | Cucurbitaceae | 8 |
| Cunila origanoides | (L.) Britton | Lamiaceae | 8 |
| Cuphea viscosissima | Jacq. | Lythraceae | 8 |
| Cuscuta campestris | Yunck. | Convolvulaceae | 8 |
| Cuscuta compacta | Juss. ex Choisy | Convolvulaceae | 8 |
| Cuscuta coryli | Engelm. | Convolvulaceae | 8 |
| Cuscuta cuspidata | Engelm. | Convolvulaceae | 8 |
| Cuscuta glomerata | Choisy | Convolvulaceae | 8 |
| Cuscuta gronovii | Willd. | Convolvulaceae | 8 |
| Cuscuta indecora | Choisy | Convolvulaceae | 8 |
| Cuscuta pentagona | Engelm. | Convolvulaceae | 8 |
| Cynanchum laeve | (Michx.) Pers. | Apocynaceae | 8 |
| Cynosciadium digitatum | DC. | Apiaceae | 8 |
| Cyperus acuminatus | Torr. & Hook. | Cyperaceae | 8 |
| Cyperus bipartitus | Torr. | Cyperaceae | 8 |
| Cyperus compressus | L. | Cyperaceae | 8 |
| Cyperus croceus | Vahl | Cyperaceae | 8 |
| Cyperus diandrus | Torr. | Cyperaceae | 8 |
| Cyperus echinatus | (L.) Alph.Wood | Cyperaceae | 8 |
| Cyperus esculentus | L. | Cyperaceae | 8 |
| Cyperus flavescens | L. | Cyperaceae | 8 |
| Cyperus lupulinus | (Biehler) Marcks | Cyperaceae | 8 |
| Cyperus odoratus | L. | Cyperaceae | 8 |
| Cyperus plukenetii | Fernald | Cyperaceae | 8 |
| Cyperus polystachyos | Rottb. | Cyperaceae | 8 |
| Cyperus pseudovegetus | Steud. | Cyperaceae | 8 |
| Cyperus refractus | Engelm. ex Boeckeler | Cyperaceae | 8 |
| Cyperus retroflexus | Buckley | Cyperaceae | 8 |
| Cyperus retrofractus | (L.) Torr. | Cyperaceae | 8 |
| Cyperus retrorsus | Chapm. | Cyperaceae | 8 |
| Cyperus schweinitzii | Torr. | Cyperaceae | 8 |
| Cyperus squarrosus | L. | Cyperaceae | 8 |
| Cyperus strigosus | L. | Cyperaceae | 8 |
| Cyperus subsquarrosus | (Muhl.) Bauters | Cyperaceae | 8 |
| Cypripedium candidum | Muhl. ex Willd. | Orchidaceae | 8 |
| Cypripedium parviflorum | Salisb. | Orchidaceae | 8 |
| Cypripedium reginae | Walter | Orchidaceae | 8 |
| Cystopteris bulbifera | (L.) Bernh. | Cystopteridaceae | 8 |
| Cystopteris protrusa | (Weath.) Blasdell | Cystopteridaceae | 8 |
| Cystopteris tennesseensis | Shaver | Cystopteridaceae | 8 |
| Cystopteris tenuis | (Michx.) Desv. | Cystopteridaceae | 8 |
| Dactylorhiza viridis | (L.) R.M.Bateman, Pridgeon & M.W.Chase | Orchidaceae | 8 |
| Dalea candida | Willd. | Fabaceae | 8 |
| Dalea enneandra | Nutt. | Fabaceae | 8 |
| Dalea leporina | (Aiton) Bullock | Fabaceae | 8 |
| Dalea multiflora | (Nutt.) Shinners | Fabaceae | 8 |
| Dalea villosa | (Nutt.) Spreng. | Fabaceae | 8 |
| Danthonia spicata | (L.) Roem. & Schult. | Poaceae | 8 |
| Dasistoma macrophylla | (Nutt.) Raf. | Orobanchaceae | 8 |
| Daucus pusillus | Michx. | Apiaceae | 8 |
| Decodon verticillatus | (L.) Elliott | Lythraceae | 8 |
| Delphinium carolinianum | Walter | Ranunculaceae | 8 |
| Delphinium tricorne | Michx. | Ranunculaceae | 8 |
| Dendrolycopodium dendroideum | (Michx.) A.Haines | Lycopodiaceae | 8 |
| Deparia acrostichoides | (Sw.) M.Kato | Athyriaceae | 8 |
| Descurainia pinnata | (Walter) Britton | Brassicaceae | 8 |
| Desmanthus illinoensis | (Michx.) MacMill. ex B.L.Rob. & Fernald | Fabaceae | 8 |
| Desmanthus leptolobus | Torr. & A.Gray | Fabaceae | 8 |
| Desmodium canescens | (L.) DC. | Fabaceae | 8 |
| Desmodium ciliare | (Muhl. ex Willd.) DC. | Fabaceae | 8 |
| Desmodium cuspidatum | (Muhl. ex Willd.) DC. ex G.Don | Fabaceae | 8 |
| Desmodium glabellum | (Michx.) DC. | Fabaceae | 8 |
| Desmodium illinoense | A.Gray | Fabaceae | 8 |
| Desmodium laevigatum | (Nutt.) DC. | Fabaceae | 8 |
| Desmodium marilandicum | (L.) DC. | Fabaceae | 8 |
| Desmodium nuttallii | (Schindl.) B.G.Schub. | Fabaceae | 8 |
| Desmodium obtusum | (Muhl. ex Willd.) DC. | Fabaceae | 8 |
| Desmodium perplexum | B.G.Schub. | Fabaceae | 8 |
| Desmodium rotundifolium | DC. | Fabaceae | 8 |
| Desmodium sessilifolium | (Torr. ex M.A.Curtis) Torr. & A.Gray | Fabaceae | 8 |
| Dianthera americana | L. | Acanthaceae | 8 |
| Diaperia prolifera | (Nutt. ex DC.) Nutt. | Asteraceae | 8 |
| Diarrhena americana | P.Beauv. | Poaceae | 8 |
| Dicentra canadensis | (Goldie) Walp. | Papaveraceae | 8 |
| Dicentra cucullaria | (L.) Bernh. | Papaveraceae | 8 |
| Dichanthelium boscii | (Poir.) Gould & C.A.Clark | Poaceae | 8 |
| Dichanthelium clandestinum | (L.) Gould | Poaceae | 8 |
| Dichanthelium commonsianum | (Ashe) Freckmann | Poaceae | 8 |
| Dichanthelium commutatum | (Schult.) Gould | Poaceae | 8 |
| Dichanthelium depauperatum | (Muhl.) Gould | Poaceae | 8 |
| Dichanthelium dichotomum | (L.) Gould | Poaceae | 8 |
| Dichanthelium implicatum | (Scribn.) Kerguélen | Poaceae | 8 |
| Dichanthelium lanuginosum | (Elliott) Gould | Poaceae | 8 |
| Dichanthelium latifolium | (L.) Harvill | Poaceae | 8 |
| Dichanthelium laxiflorum | (Lam.) Gould | Poaceae | 8 |
| Dichanthelium leibergii | (Vasey) Freckmann | Poaceae | 8 |
| Dichanthelium lindheimeri | (Nash) Gould | Poaceae | 8 |
| Dichanthelium linearifolium | (Scribn.) Gould | Poaceae | 8 |
| Dichanthelium longiligulatum | (Nash) Freckmann | Poaceae | 8 |
| Dichanthelium microcarpon | (Muhl. ex Elliott) Mohlenbr. | Poaceae | 8 |
| Dichanthelium oligosanthes | (Schult.) Gould | Poaceae | 8 |
| Dichanthelium ovale | (Elliott) Gould & C.A.Clark | Poaceae | 8 |
| Dichanthelium polyanthes | (Schult.) Mohlenbr. | Poaceae | 8 |
| Dichanthelium portoricense | (Desv.) B.F.Hansen & Wunderlin | Poaceae | 8 |
| Dichanthelium praecocius | (Hitchc. & Chase) Mohlenbr. | Poaceae | 8 |
| Dichanthelium ravenelii | (Scribn. & Merr.) Gould | Poaceae | 8 |
| Dichanthelium roanokense | (Ashe) LeBlond | Poaceae | 8 |
| Dichanthelium scoparium | (Lam.) Gould | Poaceae | 8 |
| Dichanthelium sphaerocarpon | (Elliott) Gould | Poaceae | 8 |
| Dichanthelium yadkinense | (Ashe) Mohlenbr. | Poaceae | 8 |
| Dichondra carolinensis | Michx. | Convolvulaceae | 8 |
| Dicliptera brachiata | Spreng. | Acanthaceae | 8 |
| Digitaria cognata | (Schult.) Pilg. | Poaceae | 8 |
| Digitaria filiformis | (L.) Koeler | Poaceae | 8 |
| Diodia virginiana | L. | Rubiaceae | 8 |
| Dioscorea villosa | L. | Dioscoreaceae | 8 |
| Diospyros virginiana | L. | Ebenaceae | 8 |
| Diphasiastrum digitatum | (Dill. ex A.Braun) Holub | Lycopodiaceae | 8 |
| Diphasiastrum tristachyum | (Pursh) Holub | Lycopodiaceae | 8 |
| Diplachne fusca | (L.) P.Beauv. | Poaceae | 8 |
| Diplaziopsis pycnocarpa | (Spreng.) M.G.Price | Diplaziopsidaceae | 8 |
| Dirca palustris | L. | Thymelaeaceae | 8 |
| Distichlis spicata | (L.) Greene | Poaceae | 8 |
| Dracocephalum parviflorum | Nutt. | Lamiaceae | 8 |
| Drosera brevifolia | Pursh | Droseraceae | 8 |
| Drosera intermedia | Hayne | Droseraceae | 8 |
| Drymocallis arguta | (Pursh) Rydb. | Rosaceae | 8 |
| Dryopteris carthusiana | (Vill.) H.P.Fuchs | Dryopteridaceae | 8 |
| Dryopteris celsa | (W.Palmer) | Dryopteridaceae | 8 |
| Dryopteris cristata | (L.) A.Gray | Dryopteridaceae | 8 |
| Dryopteris goldieana | (Hook. ex Goldie) A.Gray | Dryopteridaceae | 8 |
| Dryopteris intermedia | A.Gray | Dryopteridaceae | 8 |
| Dryopteris marginalis | (L.) A.Gray | Dryopteridaceae | 8 |
| Dulichium arundinaceum | (L.) Britton | Cyperaceae | 8 |
| Dyssodia papposa | (Vent.) Hitchc. | Asteraceae | 8 |
| Echinacea angustifolia | DC. | Asteraceae | 8 |
| Echinacea pallida | (Nutt.) Nutt. | Asteraceae | 8 |
| Echinacea purpurea | (L.) Moench | Asteraceae | 8 |
| Echinacea simulata | McGregor | Asteraceae | 8 |
| Echinochloa muricata | (P.Beauv.) Fernald | Poaceae | 8 |
| Echinochloa walteri | (Pursh) A.Heller | Poaceae | 8 |
| Echinocystis lobata | (Michx.) Torr. & A.Gray | Cucurbitaceae | 8 |
| Echinodorus berteroi | (Spreng.) Fassett | Alismataceae | 8 |
| Eclipta prostrata | (L.) L. | Asteraceae | 8 |
| Edrastima uniflora | (L.) Raf. | Rubiaceae | 8 |
| Elatine americana | (Pursh) Arn. | Elatinaceae | 8 |
| Eleocharis acicularis | (L.) Roem. & Schult. | Cyperaceae | 8 |
| Eleocharis atropurpurea | (Retz.) J.Presl & C.Presl | Cyperaceae | 8 |
| Eleocharis compressa | Sull. | Cyperaceae | 8 |
| Eleocharis engelmannii | Steud. | Cyperaceae | 8 |
| Eleocharis erythropoda | Steud. | Cyperaceae | 8 |
| Eleocharis macrostachya | Britton | Cyperaceae | 8 |
| Eleocharis obtusa | (Willd.) Schult. | Cyperaceae | 8 |
| Eleocharis palustris | (L.) Roem. & Schult. | Cyperaceae | 8 |
| Eleocharis parvula | (Roem. & Schult.) Link ex Bluff, Nees & Schauer | Cyperaceae | 8 |
| Eleocharis quadrangulata | (Michx.) Roem. & Schult. | Cyperaceae | 8 |
| Elephantopus carolinianus | Raeusch. | Asteraceae | 8 |
| Ellisia nyctelea | (L.) L. | Hydrophyllaceae | 8 |
| Elodea canadensis | Michx. | Hydrocharitaceae | 8 |
| Elodea nuttallii | (Planch.) H.St.John | Hydrocharitaceae | 8 |
| Elymus canadensis | L. | Poaceae | 8 |
| Elymus curvatus | Piper | Poaceae | 8 |
| Elymus glaucus | Buckley | Poaceae | 8 |
| Elymus hystrix | L. | Poaceae | 8 |
| Elymus longifolius | (J.G.Sm.) Gould | Poaceae | 8 |
| Elymus macgregorii | R.E.Brooks & J.J.N.Campb. | Poaceae | 8 |
| Elymus riparius | Wiegand | Poaceae | 8 |
| Elymus smithii | (Rydb.) Gould | Poaceae | 8 |
| Elymus villosus | Muhl. ex Willd. | Poaceae | 8 |
| Elymus virginicus | L. | Poaceae | 8 |
| Enemion biternatum | Raf. | Ranunculaceae | 8 |
| Engelmannia peristenia | (Raf.) Goodman & C.A.Lawson | Asteraceae | 8 |
| Epifagus virginiana | (L.) Barton | Orobanchaceae | 8 |
| Epilobium ciliatum | Raf. | Onagraceae | 8 |
| Epilobium coloratum | Muhl. ex Willd. | Onagraceae | 8 |
| Epilobium leptophyllum | Raf. | Onagraceae | 8 |
| Equisetum arvense | L. | Equisetaceae | 8 |
| Equisetum hyemale | L. | Equisetaceae | 8 |
| Equisetum laevigatum | A.Braun | Equisetaceae | 8 |
| Eragrostis curtipedicellata | Buckley | Poaceae | 8 |
| Eragrostis elliottii | (Elliott) S.Watson | Poaceae | 8 |
| Eragrostis hirsuta | (Michx.) Nees | Poaceae | 8 |
| Eragrostis hypnoides | (Lam.) Britton, Sterns & Poggenb. | Poaceae | 8 |
| Eragrostis intermedia | Hitchc. | Poaceae | 8 |
| Eragrostis pectinacea | (Michx.) Nees | Poaceae | 8 |
| Eragrostis refracta | (Muhl.) Scribn. | Poaceae | 8 |
| Eragrostis reptans | (Michx.) Nees | Poaceae | 8 |
| Eragrostis secundiflora | J.Presl | Poaceae | 8 |
| Eragrostis spectabilis | (Pursh) Steud. | Poaceae | 8 |
| Eragrostis trichodes | (Nutt.) Alph.Wood | Poaceae | 8 |
| Erechtites hieraciifolius | (L.) Raf. ex DC. | Asteraceae | 8 |
| Erianthus alopecuroides | (L.) Elliott | Poaceae | 8 |
| Erianthus giganteus | (Walter) P.Beauv. | Poaceae | 8 |
| Erianthus strictus | Baldwin | Poaceae | 8 |
| Erigenia bulbosa | (Michx.) Nutt. | Apiaceae | 8 |
| Erigeron annuus | (L.) Desf. | Asteraceae | 8 |
| Erigeron canadensis | L. | Asteraceae | 8 |
| Erigeron philadelphicus | L. | Asteraceae | 8 |
| Erigeron pulchellus | Michx. | Asteraceae | 8 |
| Erigeron strigosus | Muhl. ex Willd. | Asteraceae | 8 |
| Eriochloa contracta | Hitchc. | Poaceae | 8 |
| Eriogonum longifolium | Nutt. | Polygonaceae | 8 |
| Eryngium prostratum | Nutt. ex DC. | Apiaceae | 8 |
| Eryngium yuccifolium | Michx. | Apiaceae | 8 |
| Erysimum capitatum | Greene | Brassicaceae | 8 |
| Erythranthe geyeri | (Torr.) G.L.Nesom | Phrymaceae | 8 |
| Erythronium albidum | Nutt. | Liliaceae | 8 |
| Erythronium americanum | Ker Gawl. | Liliaceae | 8 |
| Erythronium mesochoreum | Knerr | Liliaceae | 8 |
| Erythronium rostratum | W.Wolf | Liliaceae | 8 |
| Euonymus americanus | L. | Celastraceae | 8 |
| Euonymus atropurpureus | Jacq. | Celastraceae | 8 |
| Euonymus obovatus | Nutt. | Celastraceae | 8 |
| Eupatorium altissimum | L. | Asteraceae | 8 |
| Eupatorium capillifolium | (Lam.) Small ex Porter & Britton | Asteraceae | 8 |
| Eupatorium hyssopifolium | L. | Asteraceae | 8 |
| Eupatorium perfoliatum | L. | Asteraceae | 8 |
| Eupatorium rotundifolium | L. | Asteraceae | 8 |
| Eupatorium serotinum | Michx. | Asteraceae | 8 |
| Eupatorium sessilifolium | L. | Asteraceae | 8 |
| Euphorbia commutata | Engelm. ex A.Gray | Euphorbiaceae | 8 |
| Euphorbia corollata | L. | Euphorbiaceae | 8 |
| Euphorbia dentata | Michx. | Euphorbiaceae | 8 |
| Euphorbia geyeri | Engelm. | Euphorbiaceae | 8 |
| Euphorbia glyptosperma | Engelm. | Euphorbiaceae | 8 |
| Euphorbia heterophylla | L. | Euphorbiaceae | 8 |
| Euphorbia hexagona | Nutt. ex Spreng. | Euphorbiaceae | 8 |
| Euphorbia humistrata | Engelm. ex A.Gray | Euphorbiaceae | 8 |
| Euphorbia maculata | L. | Euphorbiaceae | 8 |
| Euphorbia marginata | Pursh | Euphorbiaceae | 8 |
| Euphorbia missurica | Raf. | Euphorbiaceae | 8 |
| Euphorbia nutans | Lag. | Euphorbiaceae | 8 |
| Euphorbia prostrata | Aiton | Euphorbiaceae | 8 |
| Euphorbia serpens | Kunth | Euphorbiaceae | 8 |
| Euphorbia serpillifolia | Pers. | Euphorbiaceae | 8 |
| Euphorbia spathulata | Lam. | Euphorbiaceae | 8 |
| Euphorbia stictospora | Engelm. | Euphorbiaceae | 8 |
| Euploca tenella | (Torr.) Feuillet & Halse | Heliotropiaceae | 8 |
| Eurybia furcata | (E.S.Burgess) G.L.Nesom | Asteraceae | 8 |
| Eurybia macrophylla | (L.) Cass. | Asteraceae | 8 |
| Eurybia paludosa | (Aiton) G.L.Nesom | Asteraceae | 8 |
| Euthamia gymnospermoides | Greene | Asteraceae | 8 |
| Euthamia leptocephala | (Torr. & A.Gray) Greene ex Porter & Britton | Asteraceae | 8 |
| Eutrochium fistulosum | (Barratt) E.E.Lamont | Asteraceae | 8 |
| Eutrochium maculatum | (L.) E.E.Lamont | Asteraceae | 8 |
| Eutrochium purpureum | (L.) E.E.Lamont | Asteraceae | 8 |
| Evolvulus nuttallianus | Schult. | Convolvulaceae | 8 |
| Fagus grandifolia | Ehrh. | Fagaceae | 8 |
| Fallopia scandens | (L.) Holub | Polygonaceae | 8 |
| Festuca octoflora | Walter | Poaceae | 8 |
| Festuca paradoxa | Desv. | Poaceae | 8 |
| Festuca rubra | L. | Poaceae | 8 |
| Festuca subverticillata | (Pers.) E.B.Alexeev | Poaceae | 8 |
| Filipendula rubra | (Hill) B.L.Rob. | Rosaceae | 8 |
| Fimbristylis autumnalis | (L.) Roem. & Schult. | Cyperaceae | 8 |
| Fimbristylis dichotoma | (L.) Vahl | Cyperaceae | 8 |
| Fimbristylis littoralis | Gaudich. | Cyperaceae | 8 |
| Fimbristylis puberula | (Michx.) Vahl | Cyperaceae | 8 |
| Fimbristylis vahlii | (Lam.) Link | Cyperaceae | 8 |
| Fleischmannia incarnata | (Walter) R.M.King & H.Rob. | Asteraceae | 8 |
| Floerkea proserpinacoides | Willd. | Limnanthaceae | 8 |
| Forestiera acuminata | (Michx.) Poir. | Oleaceae | 8 |
| Fragaria virginiana | Mill. | Rosaceae | 8 |
| Frangula caroliniana | (Walter) A.Gray | Rhamnaceae | 8 |
| Frasera caroliniensis | Walter | Gentianaceae | 8 |
| Fraxinus americana | L. | Oleaceae | 8 |
| Fraxinus pennsylvanica | Marshall | Oleaceae | 8 |
| Fraxinus profunda | (Bush) Bush | Oleaceae | 8 |
| Fraxinus quadrangulata | Michx. | Oleaceae | 8 |
| Froelichia floridana | (Nutt.) Moq. | Amaranthaceae | 8 |
| Froelichia gracilis | (Hook.) Moq. | Amaranthaceae | 8 |
| Fuirena simplex | Vahl | Cyperaceae | 8 |
| Gaillardia aestivalis | (Walter) H.Rock | Asteraceae | 8 |
| Gaillardia pulchella | Foug. | Asteraceae | 8 |
| Galactia regularis | (L.) Britton, Sterns & Poggenb. | Fabaceae | 8 |
| Galactia volubilis | (L.) Britton | Fabaceae | 8 |
| Galearis spectabilis | (L.) Raf. | Orchidaceae | 8 |
| Galium asprellum | Michx. | Rubiaceae | 8 |
| Galium concinnum | Torr. & A.Gray | Rubiaceae | 8 |
| Galium obtusum | Bigelow | Rubiaceae | 8 |
| Galium pilosum | Aiton | Rubiaceae | 8 |
| Galium trifidum | L. | Rubiaceae | 8 |
| Galium triflorum | Michx. | Rubiaceae | 8 |
| Galium virgatum | Nutt. | Rubiaceae | 8 |
| Gamochaeta purpurea | (L.) Cabrera | Asteraceae | 8 |
| Gaylussacia baccata | (Wangenh.) K.Koch | Ericaceae | 8 |
| Gentiana alba | Muhl. ex J.McNab | Gentianaceae | 8 |
| Gentiana andrewsii | Griseb. | Gentianaceae | 8 |
| Gentiana puberulenta | J.S.Pringle | Gentianaceae | 8 |
| Gentianella quinquefolia | (L.) Small | Gentianaceae | 8 |
| Geocarpon minimum | Mack. | Caryophyllaceae | 8 |
| Geranium carolinianum | L. | Geraniaceae | 8 |
| Geranium maculatum | L. | Geraniaceae | 8 |
| Geranium robertianum | L. | Geraniaceae | 8 |
| Geum canadense | Jacq. | Rosaceae | 8 |
| Geum laciniatum | Murray | Rosaceae | 8 |
| Geum vernum | (Raf.) Torr. & A.Gray | Rosaceae | 8 |
| Geum virginianum | L. | Rosaceae | 8 |
| Gillenia stipulata | (Muhl. ex Willd.) Nutt. | Rosaceae | 8 |
| Gillenia trifoliata | (L.) Moench | Rosaceae | 8 |
| Gleditsia aquatica | Marshall | Fabaceae | 8 |
| Gleditsia triacanthos | L. | Fabaceae | 8 |
| Glyceria septentrionalis | Hitchc. | Poaceae | 8 |
| Glyceria striata | (Lam.) Hitchc. | Poaceae | 8 |
| Glycyrrhiza lepidota | Pursh | Fabaceae | 8 |
| Gonolobus suberosus | (L.) R.Br. | Apocynaceae | 8 |
| Goodyera pubescens | (Willd.) R.Br. | Orchidaceae | 8 |
| Gratiola neglecta | Torr. | Plantaginaceae | 8 |
| Gratiola virginiana | L. | Plantaginaceae | 8 |
| Grindelia ciliata | (Nutt.) Spreng. | Asteraceae | 8 |
| Grindelia hirsutula | Hook. & Arn. | Asteraceae | 8 |
| Grindelia lanceolata | Nutt. | Asteraceae | 8 |
| Grindelia squarrosa | (Pursh) Dunal | Asteraceae | 8 |
| Gutierrezia dracunculoides | (DC.) O.Hoffm. | Asteraceae | 8 |
| Gymnocladus dioicus | (L.) K.Koch | Fabaceae | 8 |
| Gymnopogon ambiguus | (Michx.) Britton, Sterns & Poggenb. | Poaceae | 8 |
| Hackelia virginiana | (L.) I.M.Johnst. | Boraginaceae | 8 |
| Halerpestes cymbalaria | Greene | Ranunculaceae | 8 |
| Hamamelis vernalis | Sarg. | Hamamelidaceae | 8 |
| Hamamelis virginiana | L. | Hamamelidaceae | 8 |
| Hasteola suaveolens | (L.) Pojark. | Asteraceae | 8 |
| Hedeoma hispida | Pursh | Lamiaceae | 8 |
| Hedeoma pulegioides | (L.) Pers. | Lamiaceae | 8 |
| Helenium amarum | (Raf.) H.Rock | Asteraceae | 8 |
| Helenium autumnale | L. | Asteraceae | 8 |
| Helenium flexuosum | Raf. | Asteraceae | 8 |
| Helianthus angustifolius | L. | Asteraceae | 8 |
| Helianthus divaricatus | L. | Asteraceae | 8 |
| Helianthus grosseserratus | M.Martens | Asteraceae | 8 |
| Helianthus hirsutus | Raf. | Asteraceae | 8 |
| Helianthus maximiliani | Schrad. | Asteraceae | 8 |
| Helianthus mollis | Lam. | Asteraceae | 8 |
| Helianthus nuttallii | Torr. & A.Gray | Asteraceae | 8 |
| Helianthus occidentalis | Riddell | Asteraceae | 8 |
| Helianthus pauciflorus | Nutt. | Asteraceae | 8 |
| Helianthus petiolaris | Nutt. | Asteraceae | 8 |
| Helianthus salicifolius | A.Dietr. | Asteraceae | 8 |
| Helianthus strumosus | L. | Asteraceae | 8 |
| Helianthus tuberosus | L. | Asteraceae | 8 |
| Heliopsis helianthoides | Sweet | Asteraceae | 8 |
| Heliotropium curassavicum | L. | Heliotropiaceae | 8 |
| Hepatica americana | (DC.) Ker Gawl. | Ranunculaceae | 8 |
| Heracleum maximum | W.Bartram | Apiaceae | 8 |
| Hesperostipa spartea | (Trin.) Barkworth | Poaceae | 8 |
| Heteranthera dubia | (Jacq.) MacMill. | Pontederiaceae | 8 |
| Heteranthera limosa | (Sw.) Willd. | Pontederiaceae | 8 |
| Heteranthera reniformis | Ruiz & Pav. | Pontederiaceae | 8 |
| Heterotheca camporum | (Greene) Shinners | Asteraceae | 8 |
| Heterotheca canescens | (DC.) Shinners | Asteraceae | 8 |
| Heterotheca subaxillaris | (Lam.) Britton & Rusby | Asteraceae | 8 |
| Heuchera americana | L. | Saxifragaceae | 8 |
| Heuchera missouriensis | Rosend. | Saxifragaceae | 8 |
| Heuchera richardsonii | R.Br. | Saxifragaceae | 8 |
| Heuchera villosa | Michx. | Saxifragaceae | 8 |
| Hexasepalum teres | (Walter) J.H.Kirkbr. | Rubiaceae | 8 |
| Hieracium gronovii | L. | Asteraceae | 8 |
| Hieracium longipilum | Torr. ex Hook. | Asteraceae | 8 |
| Hieracium scabrum | Michx. | Asteraceae | 8 |
| Hieracium umbellatum | L. | Asteraceae | 8 |
| Hieracium venosum | L. | Asteraceae | 8 |
| Hopia obtusa | (Kunth) Zuloaga & Morrone | Poaceae | 8 |
| Hordeum brachyantherum | Nevski | Poaceae | 8 |
| Hordeum jubatum | L. | Poaceae | 8 |
| Hottonia inflata | Elliott | Primulaceae | 8 |
| Houstonia caerulea | L. | Rubiaceae | 8 |
| Houstonia longifolia | Gaertn. | Rubiaceae | 8 |
| Houstonia micrantha | (Shinners) Terrell | Rubiaceae | 8 |
| Houstonia purpurea | L. | Rubiaceae | 8 |
| Houstonia pusilla | Schoepf | Rubiaceae | 8 |
| Houstonia rosea | (Raf.) Terrell | Rubiaceae | 8 |
| Huperzia lucidula | (Michx.) Trevis. | Lycopodiaceae | 8 |
| Huperzia porophila | (F.E.Lloyd & Underw.) Holub | Lycopodiaceae | 8 |
| Hybanthus concolor | Spreng. | Violaceae | 8 |
| Hydrangea arborescens | L. | Hydrangeaceae | 8 |
| Hydrastis canadensis | L. | Ranunculaceae | 8 |
| Hydrocharis spongia | Bosc | Hydrocharitaceae | 8 |
| Hydrocotyle ranunculoides | L.f. | Araliaceae | 8 |
| Hydrocotyle verticillata | Thunb. | Araliaceae | 8 |
| Hydrogalium claytonii | (Michx.) Kadereit & Schneew. | Rubiaceae | 8 |
| Hydrolea ovata | Nutt. | Hydroleaceae | 8 |
| Hydrolea uniflora | Raf. | Hydroleaceae | 8 |
| Hydrophyllum appendiculatum | Michx. | Hydrophyllaceae | 8 |
| Hydrophyllum canadense | L. | Hydrophyllaceae | 8 |
| Hydrophyllum virginianum | L. | Hydrophyllaceae | 8 |
| Hylodesmum glutinosum | (Muhl. ex Willd.) H.Ohashi & R.R.Mill | Fabaceae | 8 |
| Hylodesmum nudiflorum | (L.) H.Ohashi & R.R.Mill | Fabaceae | 8 |
| Hylodesmum pauciflorum | (Nutt.) H.Ohashi & R.R.Mill | Fabaceae | 8 |
| Hymenocallis occidentalis | (Leconte) Kunth | Amaryllidaceae | 8 |
| Hymenopappus scabiosaeus | L'Hér. | Asteraceae | 8 |
| Hypericum ascyron | L. | Hypericaceae | 8 |
| Hypericum drummondii | (Grev. & Hook.) Torr. & A.Gray | Hypericaceae | 8 |
| Hypericum gentianoides | (L.) Britton, Sterns & Poggenb. | Hypericaceae | 8 |
| Hypericum gymnanthum | Engelm. & A.Gray | Hypericaceae | 8 |
| Hypericum hypericoides | (L.) Crantz | Hypericaceae | 8 |
| Hypericum lobocarpum | Gatt. | Hypericaceae | 8 |
| Hypericum majus | (A.Gray) Britton | Hypericaceae | 8 |
| Hypericum mutilum | L. | Hypericaceae | 8 |
| Hypericum prolificum | L. | Hypericaceae | 8 |
| Hypericum pseudomaculatum | Bush | Hypericaceae | 8 |
| Hypericum punctatum | Lam. | Hypericaceae | 8 |
| Hypericum sphaerocarpum | Michx. | Hypericaceae | 8 |
| Hypericum tubulosum | Walter | Hypericaceae | 8 |
| Hypericum walteri | J.F.Gmel. | Hypericaceae | 8 |
| Hypopitys monotropa | Crantz | Ericaceae | 8 |
| Hypoxis hirsuta | (L.) Coville | Hypoxidaceae | 8 |
| Ilex decidua | Walter | Aquifoliaceae | 8 |
| Ilex opaca | Aiton | Aquifoliaceae | 8 |
| Ilex verticillata | (L.) A.Gray | Aquifoliaceae | 8 |
| Impatiens capensis | Meerb. | Balsaminaceae | 8 |
| Impatiens pallida | Nutt. | Balsaminaceae | 8 |
| Iodanthus pinnatifidus | Steud. | Brassicaceae | 8 |
| Ionactis linariifolia | (L.) Greene | Asteraceae | 8 |
| Ipomoea coccinea | L. | Convolvulaceae | 8 |
| Ipomoea lacunosa | L. | Convolvulaceae | 8 |
| Ipomoea pandurata | G.Mey. | Convolvulaceae | 8 |
| Ipomopsis rubra | (L.) Wherry | Polemoniaceae | 8 |
| Iris brevicaulis | Raf. | Iridaceae | 8 |
| Iris cristata | Aiton | Iridaceae | 8 |
| Iris fulva | Ker Gawl. | Iridaceae | 8 |
| Iris verna | L. | Iridaceae | 8 |
| Iris virginica | L. | Iridaceae | 8 |
| Isoetes butleri | Engelm. | Isoetaceae | 8 |
| Isolepis carinata | Hook. & Arn. ex Torr. | Cyperaceae | 8 |
| Isotria medeoloides | (Pursh) Raf. | Orchidaceae | 8 |
| Isotria verticillata | (Muhl. ex Willd.) Raf. | Orchidaceae | 8 |
| Itea virginica | L. | Iteaceae | 8 |
| Iva annua | L. | Asteraceae | 8 |
| Juglans cinerea | L. | Juglandaceae | 8 |
| Juglans nigra | L. | Juglandaceae | 8 |
| Juncus acuminatus | Michx. | Juncaceae | 8 |
| Juncus alpinoarticulatus | Chaix | Juncaceae | 8 |
| Juncus anthelatus | (Wiegand) R.E.Brooks & Whittem. | Juncaceae | 8 |
| Juncus balticus | Willd. | Juncaceae | 8 |
| Juncus biflorus | Elliott | Juncaceae | 8 |
| Juncus brachycarpus | Engelm. | Juncaceae | 8 |
| Juncus bufonius | L. | Juncaceae | 8 |
| Juncus canadensis | J.Gay ex Laharpe | Juncaceae | 8 |
| Juncus diffusissimus | Buckley | Juncaceae | 8 |
| Juncus dudleyi | Wiegand | Juncaceae | 8 |
| Juncus effusus | L. | Juncaceae | 8 |
| Juncus gerardi | Loisel. | Juncaceae | 8 |
| Juncus interior | Wiegand | Juncaceae | 8 |
| Juncus marginatus | Rostk. | Juncaceae | 8 |
| Juncus nodosus | L. | Juncaceae | 8 |
| Juncus pylaei | Laharpe | Juncaceae | 8 |
| Juncus scirpoides | Lam. | Juncaceae | 8 |
| Juncus tenuis | Willd. | Juncaceae | 8 |
| Juncus torreyi | Coville | Juncaceae | 8 |
| Juncus validus | Coville | Juncaceae | 8 |
| Juniperus ashei | J.Buchholz | Cupressaceae | 8 |
| Juniperus virginiana | L. | Cupressaceae | 8 |
| Justicia lanceolata | (Chapm.) Small | Acanthaceae | 8 |
| Kallstroemia parviflora | Norton | Zygophyllaceae | 8 |
| Kellochloa verrucosa | (Muhl.) Lizarazu, Nicola & Scataglini | Poaceae | 8 |
| Koeleria macrantha | (Ledeb.) Schult. | Poaceae | 8 |
| Krigia biflora | (Walter) S.F.Blake | Asteraceae | 8 |
| Krigia cespitosa | (Raf.) K.L.Chambers | Asteraceae | 8 |
| Krigia dandelion | (L.) Nutt. | Asteraceae | 8 |
| Krigia occidentalis | Nutt. | Asteraceae | 8 |
| Krigia virginica | (L.) Willd. | Asteraceae | 8 |
| Lactuca canadensis | L. | Asteraceae | 8 |
| Lactuca floridana | (L.) Gaertn. | Asteraceae | 8 |
| Lactuca hirsuta | Muhl. ex Nutt. | Asteraceae | 8 |
| Lactuca oblongifolia | Nutt. | Asteraceae | 8 |
| Laportea canadensis | (L.) Wedd. | Urticaceae | 8 |
| Lappula occidentalis | (S.Watson) Greene | Boraginaceae | 8 |
| Lathyrus palustris | L. | Fabaceae | 8 |
| Lathyrus pusillus | Elliott | Fabaceae | 8 |
| Lathyrus venosus | Muhl. ex Willd. | Fabaceae | 8 |
| Leavenworthia uniflora | (Michx.) Britton | Brassicaceae | 8 |
| Lechea mucronata | Raf. | Cistaceae | 8 |
| Lechea racemulosa | Michx. | Cistaceae | 8 |
| Lechea tenuifolia | Michx. | Cistaceae | 8 |
| Leersia lenticularis | Michx. | Poaceae | 8 |
| Leersia oryzoides | (L.) Sw. | Poaceae | 8 |
| Leersia virginica | Willd. | Poaceae | 8 |
| Lemna aequinoctialis | Welw. | Araceae | 8 |
| Lemna minor | L. | Araceae | 8 |
| Lemna minuta | Kunth | Araceae | 8 |
| Lemna trisulca | L. | Araceae | 8 |
| Lemna turionifera | Landolt | Araceae | 8 |
| Lepidium densiflorum | Schrad. | Brassicaceae | 8 |
| Lepidium oblongum | Small | Brassicaceae | 8 |
| Lepidium virginicum | L. | Brassicaceae | 8 |
| Leptochloa panicea | (Retz.) Ohwi | Poaceae | 8 |
| Leptochloa panicoides | (J.Presl) Hitchc. | Poaceae | 8 |
| Lespedeza frutescens | (L.) Hornem. | Fabaceae | 8 |
| Lespedeza hirta | (L.) Hornem. | Fabaceae | 8 |
| Lespedeza procumbens | Michx. | Fabaceae | 8 |
| Lespedeza repens | (L.) W.P.C.Barton | Fabaceae | 8 |
| Lespedeza stuevei | Nutt. | Fabaceae | 8 |
| Lespedeza violacea | (L.) Pers. | Fabaceae | 8 |
| Lespedeza virginica | (L.) Britton | Fabaceae | 8 |
| Leucospora multifida | (Michx.) Nutt. | Plantaginaceae | 8 |
| Liatris aspera | Michx. | Asteraceae | 8 |
| Liatris cylindracea | Michx. | Asteraceae | 8 |
| Liatris punctata | Hook. | Asteraceae | 8 |
| Liatris pycnostachya | Michx. | Asteraceae | 8 |
| Liatris scariosa | (L.) Willd. | Asteraceae | 8 |
| Liatris spicata | (L.) Willd. | Asteraceae | 8 |
| Liatris squarrosa | (L.) Willd. | Asteraceae | 8 |
| Liatris squarrulosa | Michx. | Asteraceae | 8 |
| Ligusticum canadense | (L.) Britton | Apiaceae | 8 |
| Lilium michiganense | Farw. | Liliaceae | 8 |
| Lilium philadelphicum | L. | Liliaceae | 8 |
| Lilium superbum | L. | Liliaceae | 8 |
| Limnosciadium pinnatum | (DC.) Mathias & Constance | Apiaceae | 8 |
| Limosella aquatica | L. | Plantaginaceae | 8 |
| Lindera benzoin | (L.) Blume | Lauraceae | 8 |
| Lindera melissifolia | (Walter) Blume | Lauraceae | 8 |
| Lindernia dubia | (L.) Pennell | Linderniaceae | 8 |
| Linum compactum | A.Nelson | Linaceae | 8 |
| Linum medium | (Planch.) Britton | Linaceae | 8 |
| Linum rigidum | Pursh | Linaceae | 8 |
| Linum striatum | Walter | Linaceae | 8 |
| Linum sulcatum | Riddell | Linaceae | 8 |
| Linum virginianum | L. | Linaceae | 8 |
| Liparis liliifolia | (L.) Rich. ex Lindl. | Orchidaceae | 8 |
| Liparis loeselii | (L.) Rich. | Orchidaceae | 8 |
| Liquidambar styraciflua | L. | Altingiaceae | 8 |
| Liriodendron tulipifera | L. | Magnoliaceae | 8 |
| Lithospermum canescens | Lehm. | Boraginaceae | 8 |
| Lithospermum caroliniense | (J.F.Gmel.) MacMill. | Boraginaceae | 8 |
| Lithospermum incisum | Lehm. | Boraginaceae | 8 |
| Lithospermum latifolium | Michx. | Boraginaceae | 8 |
| Lithospermum occidentale | (Mack.) Weakley, Witsell & D.Estes | Boraginaceae | 8 |
| Lithospermum parviflorum | Weakley, Witsell & D.Estes | Boraginaceae | 8 |
| Lithospermum subsetosum | (Mack. & Bush) Weakley, Witsell & D.Estes | Boraginaceae | 8 |
| Lobelia cardinalis | L. | Campanulaceae | 8 |
| Lobelia inflata | L. | Campanulaceae | 8 |
| Lobelia puberula | Michx. | Campanulaceae | 8 |
| Lobelia siphilitica | L. | Campanulaceae | 8 |
| Lobelia spicata | Lam. | Campanulaceae | 8 |
| Lomatium foeniculaceum | (Nutt.) J.M.Coult. & Rose | Apiaceae | 8 |
| Lomatium orientale | J.M.Coult. & Rose | Apiaceae | 8 |
| Lonicera dioica | L. | Caprifoliaceae | 8 |
| Lonicera flava | Sims | Caprifoliaceae | 8 |
| Lonicera sempervirens | L. | Caprifoliaceae | 8 |
| Lorinseria areolata | (L.) C.Presl | Blechnaceae | 8 |
| Ludwigia alternifolia | L. | Onagraceae | 8 |
| Ludwigia decurrens | Walter | Onagraceae | 8 |
| Ludwigia glandulosa | Walter | Onagraceae | 8 |
| Ludwigia grandiflora | (Michx.) Greuter & Burdet | Onagraceae | 8 |
| Ludwigia leptocarpa | (Nutt.) H.Hara | Onagraceae | 8 |
| Ludwigia linearis | Walter | Onagraceae | 8 |
| Ludwigia microcarpa | Michx. | Onagraceae | 8 |
| Ludwigia palustris | (L.) Elliott | Onagraceae | 8 |
| Ludwigia peploides | (Kunth) P.H.Raven | Onagraceae | 8 |
| Ludwigia repens | J.R.Forst. | Onagraceae | 8 |
| Luzula acuminata | Raf. | Juncaceae | 8 |
| Luzula bulbosa | (Alph.Wood) Smyth & L.C.R.Smyth | Juncaceae | 8 |
| Luzula echinata | (Small) F.J.Herm. | Juncaceae | 8 |
| Lycopus americanus | Muhl. ex W.P.C.Barton | Lamiaceae | 8 |
| Lycopus angustifolius | Elliott | Lamiaceae | 8 |
| Lycopus asper | Greene | Lamiaceae | 8 |
| Lycopus rubellus | Moench | Lamiaceae | 8 |
| Lycopus uniflorus | Michx. | Lamiaceae | 8 |
| Lycopus virginicus | L. | Lamiaceae | 8 |
| Lygodesmia juncea | (Pursh) Sweet | Asteraceae | 8 |
| Lyonia mariana | (L.) D.Don | Ericaceae | 8 |
| Lysimachia ciliata | L. | Primulaceae | 8 |
| Lysimachia hybrida | Michx. | Primulaceae | 8 |
| Lysimachia lanceolata | Walter | Primulaceae | 8 |
| Lysimachia minima | (L.) U.Manns & Anderb. | Primulaceae | 8 |
| Lysimachia quadriflora | Sims | Primulaceae | 8 |
| Lysimachia radicans | Hook. | Primulaceae | 8 |
| Lysimachia thyrsiflora | L. | Primulaceae | 8 |
| Lythrum alatum | Pursh | Lythraceae | 8 |
| Magnolia acuminata | (L.) L. | Magnoliaceae | 8 |
| Maianthemum racemosum | (L.) Link | Asparagaceae | 8 |
| Maianthemum stellatum | (L.) Link | Asparagaceae | 8 |
| Malaxis unifolia | Michx. | Orchidaceae | 8 |
| Malus angustifolia | (Aiton) Michx. | Rosaceae | 8 |
| Malus coronaria | (L.) Mill. | Rosaceae | 8 |
| Malus ioensis | (Alph.Wood) Britton | Rosaceae | 8 |
| Malvastrum hispidum | (Pursh) Hochr. | Malvaceae | 8 |
| Marshallia caespitosa | Nutt. ex DC. | Asteraceae | 8 |
| Matricaria discoidea | DC. | Asteraceae | 8 |
| Mecardonia acuminata | (Walter) Small | Plantaginaceae | 8 |
| Medeola virginiana | L. | Liliaceae | 8 |
| Melanthium virginicum | L. | Melanthiaceae | 8 |
| Melanthium woodii | (J.W.Robbins ex Alph.Wood) Bodkin | Melanthiaceae | 8 |
| Melica nitens | (Scribn.) Nutt. ex Piper | Poaceae | 8 |
| Melothria pendula | L. | Cucurbitaceae | 8 |
| Menispermum canadense | L. | Menispermaceae | 8 |
| Mentha canadensis | L. | Lamiaceae | 8 |
| Mentzelia nuda | (Pursh) Torr. & A.Gray | Loasaceae | 8 |
| Mentzelia oligosperma | Nutt. ex Sims | Loasaceae | 8 |
| Menyanthes trifoliata | L. | Menyanthaceae | 8 |
| Mertensia virginica | (L.) Pers. ex Link | Boraginaceae | 8 |
| Micranthes pensylvanica | (L.) Haw. | Saxifragaceae | 8 |
| Micranthes texana | (Buckley) Small | Saxifragaceae | 8 |
| Micranthes virginiensis | Small | Saxifragaceae | 8 |
| Mikania scandens | (L.) Willd. | Asteraceae | 8 |
| Mimosa nuttallii | (Raspail) B.L.Turner | Fabaceae | 8 |
| Mimulus alatus | Aiton | Phrymaceae | 8 |
| Mimulus ringens | L. | Phrymaceae | 8 |
| Mirabilis albida | (Walter) Heimerl | Nyctaginaceae | 8 |
| Mirabilis linearis | (Pursh) Heimerl | Nyctaginaceae | 8 |
| Mitchella repens | L. | Rubiaceae | 8 |
| Mitella diphylla | L. | Saxifragaceae | 8 |
| Mitreola petiolata | (J.F.Gmel.) Torr. & A.Gray | Loganiaceae | 8 |
| Moehringia lateriflora | (L.) Fenzl | Caryophyllaceae | 8 |
| Mollugo verticillata | L. | Molluginaceae | 8 |
| Monarda bradburyana | L.C.Beck | Lamiaceae | 8 |
| Monarda citriodora | Cerv. ex Lag. | Lamiaceae | 8 |
| Monarda fistulosa | L. | Lamiaceae | 8 |
| Monarda punctata | L. | Lamiaceae | 8 |
| Monotropa uniflora | L. | Ericaceae | 8 |
| Morus rubra | L. | Moraceae | 8 |
| Muenchhusia laevis | (All.) M.M.Hanes & R.L.Barrett | Malvaceae | 8 |
| Muenchhusia moscheutos | (L.) M.M.Hanes & R.L.Barrett | Malvaceae | 8 |
| Muhlenbergia asperifolia | (Nees & Meyen ex Trin.) Parodi | Poaceae | 8 |
| Muhlenbergia bushii | R.W.Pohl | Poaceae | 8 |
| Muhlenbergia capillaris | (Lam.) Trin. | Poaceae | 8 |
| Muhlenbergia cuspidata | (Torr. ex Hook.) Rydb. | Poaceae | 8 |
| Muhlenbergia frondosa | (Poir.) Fernald | Poaceae | 8 |
| Muhlenbergia mexicana | (L.) Trin. | Poaceae | 8 |
| Muhlenbergia paniculata | (Nutt.) P.M.Peterson | Poaceae | 8 |
| Muhlenbergia racemosa | (Michx.) Britton, Sterns & Poggenb. | Poaceae | 8 |
| Muhlenbergia schreberi | J.F.Gmel. | Poaceae | 8 |
| Muhlenbergia sylvatica | Torr. | Poaceae | 8 |
| Muhlenbergia tenuiflora | (Willd.) Britton, Sterns & Poggenb. | Poaceae | 8 |
| Myosotis macrosperma | Engelm. | Boraginaceae | 8 |
| Myosotis verna | Nutt. | Boraginaceae | 8 |
| Myriophyllum heterophyllum | Michx. | Haloragaceae | 8 |
| Myriophyllum pinnatum | (Walter) Britton, Sterns & Poggenb. | Haloragaceae | 8 |
| Myriophyllum sibiricum | Kom. | Haloragaceae | 8 |
| Myriopteris alabamensis | (Buckley) Grusz & Windham | Pteridaceae | 8 |
| Myriopteris lanosa | (Michx.) Grusz & Windham | Pteridaceae | 8 |
| Myriopteris tomentosa | (Link) Fée | Pteridaceae | 8 |
| Nabalus albus | (L.) Hook. | Asteraceae | 8 |
| Nabalus altissimus | (L.) Hook. | Asteraceae | 8 |
| Nabalus crepidineus | (Michx.) DC. | Asteraceae | 8 |
| Nabalus racemosus | (Michx.) Hook. | Asteraceae | 8 |
| Najas flexilis | (Willd.) Rostk. & W.L.E.Schmidt | Hydrocharitaceae | 8 |
| Najas guadalupensis | (Spreng.) Magnus | Hydrocharitaceae | 8 |
| Nekemias arborea | (L.) J.Wen & Boggan | Vitaceae | 8 |
| Neltuma odorata | (Torr. & Frém.) C.E.Hughes & G.P.Lewis | Fabaceae | 8 |
| Nelumbo lutea | (Willd.) Pers. | Nelumbonaceae | 8 |
| Nemastylis geminiflora | Nutt. | Iridaceae | 8 |
| Nephroia carolina | (L.) L.Lian & Wei Wang | Menispermaceae | 8 |
| Nothocalais cuspidata | (Pursh) Greene | Asteraceae | 8 |
| Nothoscordum bivalve | (L.) Britton | Amaryllidaceae | 8 |
| Nuphar advena | (Aiton) W.T.Aiton | Nymphaeaceae | 8 |
| Nuttallanthus canadensis | (L.) D.A.Sutton | Plantaginaceae | 8 |
| Nuttallanthus texanus | (Scheele) D.A.Sutton | Plantaginaceae | 8 |
| Nymphaea odorata | Aiton | Nymphaeaceae | 8 |
| Nyssa aquatica | L. | Nyssaceae | 8 |
| Nyssa biflora | Walter | Nyssaceae | 8 |
| Nyssa sylvatica | Marshall | Nyssaceae | 8 |
| Obolaria virginica | L. | Gentianaceae | 8 |
| Odontostephana baldwyniana | (Sweet) Alexander | Apocynaceae | 8 |
| Odontostephana decipiens | Alexander | Apocynaceae | 8 |
| Oenothera biennis | L. | Onagraceae | 8 |
| Oenothera clelandii | W.Dietr., P.H.Raven & W.L.Wagner | Onagraceae | 8 |
| Oenothera curtiflora | W.L.Wagner & Hoch | Onagraceae | 8 |
| Oenothera filiformis | (Small) W.L.Wagner & Hoch | Onagraceae | 8 |
| Oenothera filipes | (Spach) W.L.Wagner & Hoch | Onagraceae | 8 |
| Oenothera fruticosa | L. | Onagraceae | 8 |
| Oenothera glaucifolia | W.L.Wagner & Hoch | Onagraceae | 8 |
| Oenothera grandis | Smyth | Onagraceae | 8 |
| Oenothera laciniata | Hill | Onagraceae | 8 |
| Oenothera linifolia | Nutt. | Onagraceae | 8 |
| Oenothera macrocarpa | Nutt. | Onagraceae | 8 |
| Oenothera parviflora | L. | Onagraceae | 8 |
| Oenothera perennis | L. | Onagraceae | 8 |
| Oenothera pilosella | Raf. | Onagraceae | 8 |
| Oenothera rhombipetala | Nutt. ex Torr. & A.Gray | Onagraceae | 8 |
| Oenothera serrulata | Nutt. | Onagraceae | 8 |
| Oenothera speciosa | Nutt. | Onagraceae | 8 |
| Oenothera suffrutescens | (Ser.) W.L.Wagner & Hoch | Onagraceae | 8 |
| Oenothera tetragona | Roth | Onagraceae | 8 |
| Oenothera triloba | Nutt. | Onagraceae | 8 |
| Oenothera villosa | Thunb. | Onagraceae | 8 |
| Onoclea sensibilis | L. | Onocleaceae | 8 |
| Ophioglossum crotalophoroides | Walter | Ophioglossaceae | 8 |
| Ophioglossum engelmannii | Prantl | Ophioglossaceae | 8 |
| Ophioglossum vulgatum | L. | Ophioglossaceae | 8 |
| Oplismenus compositus | (L.) P.Beauv. | Poaceae | 8 |
| Opuntia cespitosa | Raf. | Cactaceae | 8 |
| Opuntia macrorhiza | Engelm. | Cactaceae | 8 |
| Orbexilum pedunculatum | (Mill.) Rydb. | Fabaceae | 8 |
| Orobanche ludoviciana | Nutt. | Orobanchaceae | 8 |
| Orobanche uniflora | L. | Orobanchaceae | 8 |
| Osmorhiza claytonii | C.B.Clarke | Apiaceae | 8 |
| Osmorhiza longistylis | DC. | Apiaceae | 8 |
| Osmunda spectabilis | Willd. | Osmundaceae | 8 |
| Osmundastrum cinnamomeum | (L.) C.Presl | Osmundaceae | 8 |
| Ostrya virginiana | (Mill.) K.Koch | Betulaceae | 8 |
| Oxalis colorea | (Small) R.Knuth | Oxalidaceae | 8 |
| Oxalis dillenii | Jacq. | Oxalidaceae | 8 |
| Oxalis florida | Salisb. | Oxalidaceae | 8 |
| Oxalis stricta | L. | Oxalidaceae | 8 |
| Oxalis violacea | L. | Oxalidaceae | 8 |
| Oxybaphus nyctagineus | (Michx.) Sweet | Nyctaginaceae | 8 |
| Oxypolis rigidior | (L.) Raf. | Apiaceae | 8 |
| Oxytropis lambertii | Pursh | Fabaceae | 8 |
| Packera aurea | (L.) Á.Löve & D.Löve | Asteraceae | 8 |
| Packera glabella | (Poir.) C.Jeffrey | Asteraceae | 8 |
| Packera paupercula | (Michx.) Á.Löve & D.Löve | Asteraceae | 8 |
| Packera plattensis | (Nutt.) W.A.Weber & Á.Löve | Asteraceae | 8 |
| Packera pseudaurea | (Rydb.) W.A.Weber & Á.Löve | Asteraceae | 8 |
| Palafoxia callosa | (Nutt.) Torr. & A.Gray | Asteraceae | 8 |
| Panax quinquefolius | L. | Araliaceae | 8 |
| Panicum capillare | L. | Poaceae | 8 |
| Panicum dichotomiflorum | Michx. | Poaceae | 8 |
| Panicum flexile | (Gatt.) Scribn. | Poaceae | 8 |
| Panicum virgatum | L. | Poaceae | 8 |
| Parietaria pensylvanica | Muhl. ex Willd. | Urticaceae | 8 |
| Parnassia grandifolia | DC. | Celastraceae | 8 |
| Paronychia canadensis | (L.) Alph.Wood | Caryophyllaceae | 8 |
| Paronychia fastigiata | (Raf.) Fernald | Caryophyllaceae | 8 |
| Paronychia virginica | Spreng. | Caryophyllaceae | 8 |
| Parthenium integrifolium | L. | Asteraceae | 8 |
| Parthenocissus quinquefolia | (L.) Planch. | Vitaceae | 8 |
| Paspalum distichum | L. | Poaceae | 8 |
| Paspalum floridanum | Michx. | Poaceae | 8 |
| Paspalum laeve | Michx. | Poaceae | 8 |
| Paspalum pubiflorum | Rupr. ex E.Fourn. | Poaceae | 8 |
| Paspalum repens | P.J.Bergius | Poaceae | 8 |
| Paspalum setaceum | Michx. | Poaceae | 8 |
| Passiflora incarnata | L. | Passifloraceae | 8 |
| Passiflora lutea | L. | Passifloraceae | 8 |
| Patis racemosa | (Sm.) Romasch., P.M.Peterson & Soreng | Poaceae | 8 |
| Pedicularis canadensis | L. | Orobanchaceae | 8 |
| Pedicularis lanceolata | Michx. | Orobanchaceae | 8 |
| Pediomelum argophyllum | (Pursh) J.W.Grimes | Fabaceae | 8 |
| Pediomelum esculentum | (Pursh) Rydb. | Fabaceae | 8 |
| Pediomelum tenuiflorum | (Pursh) A.N.Egan | Fabaceae | 8 |
| Pelecyphora missouriensis | (Sweet) D.Aquino & Dan.Sánchez | Cactaceae | 8 |
| Pellaea atropurpurea | (L.) Link | Pteridaceae | 8 |
| Pellaea gastonyi | Windham | Pteridaceae | 8 |
| Pellaea glabella | Mett. | Pteridaceae | 8 |
| Peltandra virginica | (L.) Schott | Araceae | 8 |
| Penstemon arkansanus | Pennell | Plantaginaceae | 8 |
| Penstemon bradburyi | Pursh | Plantaginaceae | 8 |
| Penstemon calycosus | Small | Plantaginaceae | 8 |
| Penstemon cobaea | Nutt. | Plantaginaceae | 8 |
| Penstemon digitalis | Nutt. ex Sims | Plantaginaceae | 8 |
| Penstemon pallidus | Small | Plantaginaceae | 8 |
| Penstemon tenuis | Small | Plantaginaceae | 8 |
| Penstemon tubaeflorus | Nutt. | Plantaginaceae | 8 |
| Penthorum sedoides | L. | Penthoraceae | 8 |
| Perideridia americana | (Nutt. ex DC.) Rchb. ex Steud. | Apiaceae | 8 |
| Persicaria amphibia | (L.) Delarbre | Polygonaceae | 8 |
| Persicaria arifolia | (L.) Haraldson | Polygonaceae | 8 |
| Persicaria bicornis | (Raf.) Nieuwl. | Polygonaceae | 8 |
| Persicaria glabra | (Willd.) M.Gómez | Polygonaceae | 8 |
| Persicaria hydropiperoides | (Michx.) Small | Polygonaceae | 8 |
| Persicaria lapathifolia | (L.) Delarbre | Polygonaceae | 8 |
| Persicaria pensylvanica | (L.) M.Gómez | Polygonaceae | 8 |
| Persicaria punctata | Small | Polygonaceae | 8 |
| Persicaria robustior | (Small) E.P.Bicknell | Polygonaceae | 8 |
| Persicaria sagittata | (L.) H.Gross | Polygonaceae | 8 |
| Persicaria setacea | Small | Polygonaceae | 8 |
| Persicaria virginiana | (L.) Gaertn. | Polygonaceae | 8 |
| Phacelia bipinnatifida | Michx. | Hydrophyllaceae | 8 |
| Phacelia gilioides | Brand | Hydrophyllaceae | 8 |
| Phacelia hirsuta | Nutt. | Hydrophyllaceae | 8 |
| Phacelia purshii | Buckley | Hydrophyllaceae | 8 |
| Phacelia ranunculacea | (Nutt.) Constance | Hydrophyllaceae | 8 |
| Phalaris arundinacea | L. | Poaceae | 8 |
| Phalaris caroliniana | Walter | Poaceae | 8 |
| Phaseolus polystachios | (L.) Britton, Sterns & Poggenb. | Fabaceae | 8 |
| Phemeranthus calycinus | (Engelm.) Kiger | Montiaceae | 8 |
| Phemeranthus parviflorus | (Nutt.) Kiger | Montiaceae | 8 |
| Philadelphus pubescens | Loisel. | Hydrangeaceae | 8 |
| Phlox amplifolia | Britton | Polemoniaceae | 8 |
| Phlox bifida | L.C.Beck | Polemoniaceae | 8 |
| Phlox carolina | L. | Polemoniaceae | 8 |
| Phlox divaricata | L. | Polemoniaceae | 8 |
| Phlox drummondii | Hook. | Polemoniaceae | 8 |
| Phlox glaberrima | L. | Polemoniaceae | 8 |
| Phlox paniculata | L. | Polemoniaceae | 8 |
| Phlox pilosa | L. | Polemoniaceae | 8 |
| Phoradendron leucarpum | (Raf.) Reveal & M.C.Johnst. | Santalaceae | 8 |
| Phragmites australis | (Cav.) Steud. | Poaceae | 8 |
| Phryma leptostachya | L. | Phrymaceae | 8 |
| Phyla cuneifolia | (Torr.) Greene | Verbenaceae | 8 |
| Phyla lanceolata | (Michx.) Greene | Verbenaceae | 8 |
| Phyla nodiflora | (L.) Greene | Verbenaceae | 8 |
| Phyllanthopsis phyllanthoides | (Nutt.) Voronts. & Petra Hoffm. | Phyllanthaceae | 8 |
| Phyllanthus caroliniensis | Walter | Phyllanthaceae | 8 |
| Phyllanthus polygonoides | Nutt. ex Spreng. | Phyllanthaceae | 8 |
| Physalis cordata | Mill. | Solanaceae | 8 |
| Physalis grisea | (Waterf.) M.Martínez | Solanaceae | 8 |
| Physalis heterophylla | Nees | Solanaceae | 8 |
| Physalis longifolia | Nutt. | Solanaceae | 8 |
| Physalis pubescens | L. | Solanaceae | 8 |
| Physalis pumila | Nutt. | Solanaceae | 8 |
| Physalis virginiana | Mill. | Solanaceae | 8 |
| Physocarpus intermedius | (Rydb.) C.K.Schneid. | Rosaceae | 8 |
| Physostegia angustifolia | Fernald | Lamiaceae | 8 |
| Physostegia intermedia | (Nutt.) Engelm. & A.Gray | Lamiaceae | 8 |
| Physostegia virginiana | (L.) Benth. | Lamiaceae | 8 |
| Phytolacca americana | L. | Phytolaccaceae | 8 |
| Pilea microphylla | (L.) Liebm. | Urticaceae | 8 |
| Pilea pumila | A.Gray | Urticaceae | 8 |
| Pilularia americana | A.Br. | Marsileaceae | 8 |
| Pinus banksiana | Lamb. | Pinaceae | 8 |
| Pinus echinata | Mill. | Pinaceae | 8 |
| Piptochaetium avenaceum | (L.) Parodi | Poaceae | 8 |
| Planera aquatica | J.F.Gmel. | Ulmaceae | 8 |
| Planodes virginicum | (L.) Greene | Brassicaceae | 8 |
| Plantago aristata | Michx. | Plantaginaceae | 8 |
| Plantago cordata | Lam. | Plantaginaceae | 8 |
| Plantago heterophylla | Nutt. | Plantaginaceae | 8 |
| Plantago patagonica | Jacq. | Plantaginaceae | 8 |
| Plantago rhodosperma | Decne. | Plantaginaceae | 8 |
| Plantago rugelii | Decne. | Plantaginaceae | 8 |
| Plantago virginica | L. | Plantaginaceae | 8 |
| Platanthera ciliaris | (L.) Lindl. | Orchidaceae | 8 |
| Platanthera flava | (L.) Lindl. | Orchidaceae | 8 |
| Platanthera lacera | (Michx.) G.Don | Orchidaceae | 8 |
| Platanthera leucophaea | (Nutt.) Lindl. | Orchidaceae | 8 |
| Platanthera peramoena | A.Gray | Orchidaceae | 8 |
| Platanthera psycodes | (L.) Lindl. | Orchidaceae | 8 |
| Platanus occidentalis | L. | Platanaceae | 8 |
| Plectocephalus americanus | (Nutt.) D.Don | Asteraceae | 8 |
| Pleopeltis michauxiana | (Weath.) Hickey & Sprunt | Polypodiaceae | 8 |
| Pluchea foetida | (L.) DC. | Asteraceae | 8 |
| Poa interior | Rydb. | Poaceae | 8 |
| Poa nemoralis | L. | Poaceae | 8 |
| Poa palustris | L. | Poaceae | 8 |
| Poa pratensis | L. | Poaceae | 8 |
| Poa sylvestris | A.Gray | Poaceae | 8 |
| Podophyllum peltatum | L. | Berberidaceae | 8 |
| Pogonia ophioglossoides | (L.) Ker Gawl. | Orchidaceae | 8 |
| Polemonium reptans | L. | Polemoniaceae | 8 |
| Polygala senega | L. | Polygalaceae | 8 |
| Polygonatum biflorum | (Walter) Elliott | Asparagaceae | 8 |
| Polygonum achoreum | S.F.Blake | Polygonaceae | 8 |
| Polygonum aviculare | L. | Polygonaceae | 8 |
| Polygonum tenue | Michx. | Polygonaceae | 8 |
| Polymnia canadensis | L. | Asteraceae | 8 |
| Polymnia laevigata | Beadle | Asteraceae | 8 |
| Polypodium virginianum | L. | Polypodiaceae | 8 |
| Polypremum procumbens | L. | Tetrachondraceae | 8 |
| Polystichum acrostichoides | (Michx.) Schott | Dryopteridaceae | 8 |
| Polytaenia nuttallii | DC. | Apiaceae | 8 |
| Pomaria jamesii | (Torr. & A.Gray) Walp. | Fabaceae | 8 |
| Pontederia cordata | L. | Pontederiaceae | 8 |
| Populus deltoides | W.Bartram ex Marshall | Salicaceae | 8 |
| Populus grandidentata | Michx. | Salicaceae | 8 |
| Populus heterophylla | L. | Salicaceae | 8 |
| Populus tremuloides | Michx. | Salicaceae | 8 |
| Portulaca pilosa | L. | Portulacaceae | 8 |
| Portulaca umbraticola | Kunth | Portulacaceae | 8 |
| Potamogeton amplifolius | Tuck. | Potamogetonaceae | 8 |
| Potamogeton diversifolius | Raf. | Potamogetonaceae | 8 |
| Potamogeton foliosus | Raf. | Potamogetonaceae | 8 |
| Potamogeton illinoensis | Morong | Potamogetonaceae | 8 |
| Potamogeton nodosus | Poir. | Potamogetonaceae | 8 |
| Potamogeton pusillus | L. | Potamogetonaceae | 8 |
| Potentilla canadensis | L. | Rosaceae | 8 |
| Potentilla norvegica | L. | Rosaceae | 8 |
| Potentilla rivalis | Nutt. | Rosaceae | 8 |
| Potentilla simplex | Michx. | Rosaceae | 8 |
| Potentilla supina | L. | Rosaceae | 8 |
| Primula fassettii | A.R.Mast & Reveal | Primulaceae | 8 |
| Primula frenchii | (Vasey) A.R.Mast & Reveal | Primulaceae | 8 |
| Primula meadia | (L.) A.R.Mast & Reveal | Primulaceae | 8 |
| Proboscidea louisianica | (Mill.) Thell. | Martyniaceae | 8 |
| Prunella vulgaris | L. | Lamiaceae | 8 |
| Prunus americana | Marshall | Rosaceae | 8 |
| Prunus angustifolia | Marshall | Rosaceae | 8 |
| Prunus mexicana | S.Watson | Rosaceae | 8 |
| Prunus rivularis | Scheele | Rosaceae | 8 |
| Prunus serotina | Ehrh. | Rosaceae | 8 |
| Prunus virginiana | L. | Rosaceae | 8 |
| Ptelea trifoliata | L. | Rutaceae | 8 |
| Pteridium aquilinum | (L.) Kuhn | Dennstaedtiaceae | 8 |
| Ptilimnium capillaceum | (Michx.) Raf. | Apiaceae | 8 |
| Ptilimnium costatum | Raf. | Apiaceae | 8 |
| Ptilimnium nuttallii | (DC.) Britton | Apiaceae | 8 |
| Pycnanthemum albescens | Torr. & A.Gray | Lamiaceae | 8 |
| Pycnanthemum muticum | (Michx.) Pers. | Lamiaceae | 8 |
| Pycnanthemum tenuifolium | Schrad. | Lamiaceae | 8 |
| Pycnanthemum verticillatum | (Michx.) Pers. | Lamiaceae | 8 |
| Pycnanthemum virginianum | (L.) T.Durand & B.D.Jacks. ex B.L.Rob. & Fernald | Lamiaceae | 8 |
| Pyrrhopappus carolinianus | (Walter) DC. | Asteraceae | 8 |
| Quercus alba | L. | Fagaceae | 8 |
| Quercus bicolor | Willd. | Fagaceae | 8 |
| Quercus coccinea | Münchh. | Fagaceae | 8 |
| Quercus falcata | Michx. | Fagaceae | 8 |
| Quercus imbricaria | Michx. | Fagaceae | 8 |
| Quercus lyrata | Walter | Fagaceae | 8 |
| Quercus macrocarpa | Michx. | Fagaceae | 8 |
| Quercus marilandica | (L.) Münchh. | Fagaceae | 8 |
| Quercus michauxii | Nutt. | Fagaceae | 8 |
| Quercus montana | Willd. | Fagaceae | 8 |
| Quercus muehlenbergii | Engelm. | Fagaceae | 8 |
| Quercus nigra | L. | Fagaceae | 8 |
| Quercus pagoda | Raf. | Fagaceae | 8 |
| Quercus palustris | Münchh. | Fagaceae | 8 |
| Quercus phellos | L. | Fagaceae | 8 |
| Quercus prinoides | Willd. | Fagaceae | 8 |
| Quercus rubra | L. | Fagaceae | 8 |
| Quercus shumardii | Buckley | Fagaceae | 8 |
| Quercus stellata | Wangenh. | Fagaceae | 8 |
| Quercus texana | Buckley | Fagaceae | 8 |
| Quercus velutina | Lam. | Fagaceae | 8 |
| Ranunculus abortivus | L. | Ranunculaceae | 8 |
| Ranunculus carolinianus | DC. | Ranunculaceae | 8 |
| Ranunculus fascicularis | Muhl. ex Bigelow | Ranunculaceae | 8 |
| Ranunculus flabellaris | Raf. | Ranunculaceae | 8 |
| Ranunculus harveyi | (A.Gray) Britton | Ranunculaceae | 8 |
| Ranunculus hispidus | Michx. | Ranunculaceae | 8 |
| Ranunculus micranthus | Nutt. | Ranunculaceae | 8 |
| Ranunculus minimus | E.H.L.Krause | Ranunculaceae | 8 |
| Ranunculus pusillus | Poir. | Ranunculaceae | 8 |
| Ranunculus recurvatus | Poir. | Ranunculaceae | 8 |
| Ranunculus sceleratus | L. | Ranunculaceae | 8 |
| Ranunculus trichophyllus | Chaix | Ranunculaceae | 8 |
| Ratibida columnifera | (Nutt.) Wooton & Standl. | Asteraceae | 8 |
| Ratibida pinnata | (Vent.) Barnhart | Asteraceae | 8 |
| Rhamnus lanceolata | Pursh | Rhamnaceae | 8 |
| Rhexia mariana | L. | Melastomataceae | 8 |
| Rhexia virginica | L. | Melastomataceae | 8 |
| Rhododendron prinophyllum | (Small) Millais | Ericaceae | 8 |
| Rhus aromatica | Aiton | Anacardiaceae | 8 |
| Rhus copallinum | L. | Anacardiaceae | 8 |
| Rhus glabra | L. | Anacardiaceae | 8 |
| Rhynchospora capillacea | Torr. | Cyperaceae | 8 |
| Rhynchospora capitellata | (Michx.) Vahl | Cyperaceae | 8 |
| Rhynchospora corniculata | (Lam.) A.Gray | Cyperaceae | 8 |
| Rhynchospora globularis | (Chapm.) Small | Cyperaceae | 8 |
| Rhynchospora harveyi | W.Boott | Cyperaceae | 8 |
| Rhynchospora macrostachya | Torr. ex A.Gray | Cyperaceae | 8 |
| Rhynchospora recognita | (Gale) Kral | Cyperaceae | 8 |
| Ribes americanum | Mill. | Grossulariaceae | 8 |
| Ribes aureum | Pursh | Grossulariaceae | 8 |
| Ribes cynosbati | L. | Grossulariaceae | 8 |
| Ribes missouriense | Nutt. | Grossulariaceae | 8 |
| Rorippa curvipes | Greene | Brassicaceae | 8 |
| Rorippa palustris | (L.) Besser | Brassicaceae | 8 |
| Rorippa sessiliflora | (Nutt.) Hitchc. | Brassicaceae | 8 |
| Rosa arkansana | Porter | Rosaceae | 8 |
| Rosa blanda | Aiton | Rosaceae | 8 |
| Rosa carolina | L. | Rosaceae | 8 |
| Rosa palustris | Marshall | Rosaceae | 8 |
| Rosa setigera | Michx. | Rosaceae | 8 |
| Rosa virginiana | Mill. | Rosaceae | 8 |
| Rotala ramosior | (L.) Koehne | Lythraceae | 8 |
| Rottboellia campestris | Nutt. | Poaceae | 8 |
| Rubus allegheniensis | Porter | Rosaceae | 8 |
| Rubus flagellaris | Willd. | Rosaceae | 8 |
| Rubus idaeus | L. | Rosaceae | 8 |
| Rubus occidentalis | L. | Rosaceae | 8 |
| Rubus odoratus | L. | Rosaceae | 8 |
| Rubus pascuus | L.H.Bailey | Rosaceae | 8 |
| Rubus serratus | J.F.Gmel. | Rosaceae | 8 |
| Rubus trivialis | Michx. | Rosaceae | 8 |
| Rudbeckia amplexicaulis | Vahl | Asteraceae | 8 |
| Rudbeckia fulgida | Aiton | Asteraceae | 8 |
| Rudbeckia hirta | L. | Asteraceae | 8 |
| Rudbeckia laciniata | L. | Asteraceae | 8 |
| Rudbeckia missouriensis | Engelm. ex C.L.Boynton & Beadle | Asteraceae | 8 |
| Rudbeckia subtomentosa | Pursh | Asteraceae | 8 |
| Rudbeckia triloba | L. | Asteraceae | 8 |
| Ruellia humilis | Nutt. | Acanthaceae | 8 |
| Ruellia pedunculata | Torr. ex A.Gray | Acanthaceae | 8 |
| Ruellia strepens | L. | Acanthaceae | 8 |
| Rumex altissimus | Alph.Wood | Polygonaceae | 8 |
| Rumex hastatulus | Baldwin | Polygonaceae | 8 |
| Rumex maritimus | L. | Polygonaceae | 8 |
| Rumex triangulivalvis | (Danser) Rech.f. | Polygonaceae | 8 |
| Rumex verticillatus | L. | Polygonaceae | 8 |
| Ruppia cirrhosa | (Petagna) Grande | Ruppiaceae | 8 |
| Sabatia angularis | (L.) Pursh | Gentianaceae | 8 |
| Sabatia brachiata | Elliott | Gentianaceae | 8 |
| Sabatia campestris | Nutt. | Gentianaceae | 8 |
| Sabulina michauxii | (Fenzl) Dillenb. & Kadereit | Caryophyllaceae | 8 |
| Sabulina patula | (Michx.) Small ex Rydb. | Caryophyllaceae | 8 |
| Sacciolepis striata | (L.) Nash | Poaceae | 8 |
| Sagina decumbens | (Elliott) Torr. & A.Gray | Caryophyllaceae | 8 |
| Sagittaria australis | (J.G.Sm.) Small | Alismataceae | 8 |
| Sagittaria brevirostra | Mack. & Bush | Alismataceae | 8 |
| Sagittaria cristata | Engelm. | Alismataceae | 8 |
| Sagittaria graminea | Michx. | Alismataceae | 8 |
| Sagittaria latifolia | Willd. | Alismataceae | 8 |
| Sagittaria montevidensis | Cham. & Schltdl. | Alismataceae | 8 |
| Sagittaria platyphylla | (Engelm.) J.G.Sm. | Alismataceae | 8 |
| Sagittaria rigida | Pursh | Alismataceae | 8 |
| Salix amygdaloides | Andersson | Salicaceae | 8 |
| Salix caroliniana | Michx. | Salicaceae | 8 |
| Salix discolor | Muhl. | Salicaceae | 8 |
| Salix eriocephala | Michx. | Salicaceae | 8 |
| Salix humilis | Marshall | Salicaceae | 8 |
| Salix interior | Rowlee | Salicaceae | 8 |
| Salix nigra | Marshall | Salicaceae | 8 |
| Salix sericea | Marshall | Salicaceae | 8 |
| Salvia azurea | Lam. ex Vahl | Lamiaceae | 8 |
| Salvia lyrata | L. | Lamiaceae | 8 |
| Salvia reflexa | Hornem. | Lamiaceae | 8 |
| Sambucus canadensis | L. | Viburnaceae | 8 |
| Sambucus racemosa | L. | Viburnaceae | 8 |
| Samolus parviflorus | Raf. | Primulaceae | 8 |
| Sanguinaria canadensis | L. | Papaveraceae | 8 |
| Sanicula canadensis | L. | Apiaceae | 8 |
| Sanicula marilandica | L. | Apiaceae | 8 |
| Sanicula odorata | (Raf.) K.M.Pryer & L.R.Phillippe | Apiaceae | 8 |
| Sanicula smallii | E.P.Bicknell | Apiaceae | 8 |
| Sapindus drummondii | Hook. & Arn. | Sapindaceae | 8 |
| Sassafras albidum | (Nutt.) Nees | Lauraceae | 8 |
| Saururus cernuus | L. | Saururaceae | 8 |
| Sceptridium biternatum | (Savigny) Lyon | Ophioglossaceae | 8 |
| Sceptridium dissectum | (Spreng.) Lyon | Ophioglossaceae | 8 |
| Schizachyrium scoparium | (Michx.) Nash | Poaceae | 8 |
| Schoenoplectiella purshiana | (Fernald) Lye | Cyperaceae | 8 |
| Schoenoplectus acutus | (Muhl. ex Bigelow) Á.Löve & D.Löve | Cyperaceae | 8 |
| Schoenoplectus americanus | (Pers.) Volkart | Cyperaceae | 8 |
| Schoenoplectus etuberculatus | (Steud.) Soják | Cyperaceae | 8 |
| Schoenoplectus heterochaetus | (Chase) Soják | Cyperaceae | 8 |
| Schoenoplectus pungens | (Vahl) Palla | Cyperaceae | 8 |
| Schoenoplectus subterminalis | (Torr.) Soják | Cyperaceae | 8 |
| Schoenoplectus tabernaemontani | (C.C.Gmel.) Palla | Cyperaceae | 8 |
| Schoenoplectus torreyi | (Olney) Palla | Cyperaceae | 8 |
| Scirpus atrovirens | Willd. | Cyperaceae | 8 |
| Scirpus cyperinus | (L.) Kunth | Cyperaceae | 8 |
| Scirpus georgianus | R.M.Harper | Cyperaceae | 8 |
| Scirpus pedicellatus | Fernald | Cyperaceae | 8 |
| Scirpus pendulus | Muhl. | Cyperaceae | 8 |
| Scirpus polyphyllus | Vahl | Cyperaceae | 8 |
| Scleria ciliata | Michx. | Cyperaceae | 8 |
| Scleria muehlenbergii | Steud. | Cyperaceae | 8 |
| Scleria oligantha | Michx. | Cyperaceae | 8 |
| Scleria pauciflora | Muhl. ex Willd. | Cyperaceae | 8 |
| Scleria triglomerata | Michx. | Cyperaceae | 8 |
| Scleria verticillata | Muhl. ex Willd. | Cyperaceae | 8 |
| Scrophularia lanceolata | Pursh | Scrophulariaceae | 8 |
| Scrophularia marilandica | L. | Scrophulariaceae | 8 |
| Scutellaria elliptica | Muhl. | Lamiaceae | 8 |
| Scutellaria galericulata | L. | Lamiaceae | 8 |
| Scutellaria incana | Biehler | Lamiaceae | 8 |
| Scutellaria lateriflora | L. | Lamiaceae | 8 |
| Scutellaria ovata | Hill | Lamiaceae | 8 |
| Scutellaria parvula | Michx. | Lamiaceae | 8 |
| Sedum nuttallii | Torr. & E.James ex Eaton | Crassulaceae | 8 |
| Sedum pulchellum | Michx. | Crassulaceae | 8 |
| Sedum ternatum | Michx. | Crassulaceae | 8 |
| Selaginella apoda | Spring | Selaginellaceae | 8 |
| Selaginella eclipes | W.R.Buck | Selaginellaceae | 8 |
| Selaginella rupestris | (L.) Spring | Selaginellaceae | 8 |
| Selenia aurea | Nutt. | Brassicaceae | 8 |
| Senna hebecarpa | (Fernald) H.S.Irwin & Barneby | Fabaceae | 8 |
| Senna marilandica | (L.) Link | Fabaceae | 8 |
| Senna obtusifolia | (L.) H.S.Irwin & Barneby | Fabaceae | 8 |
| Setaria parviflora | (Poir.) Kerguélen | Poaceae | 8 |
| Sicyos angulatus | L. | Cucurbitaceae | 8 |
| Sida elliottii | Torr. & A.Gray | Malvaceae | 8 |
| Sideroxylon lanuginosum | Michx. | Sapotaceae | 8 |
| Sideroxylon lycioides | L. | Sapotaceae | 8 |
| Silene antirrhina | L. | Caryophyllaceae | 8 |
| Silene caroliniana | Walter | Caryophyllaceae | 8 |
| Silene regia | Sims | Caryophyllaceae | 8 |
| Silene stellata | W.T.Aiton | Caryophyllaceae | 8 |
| Silene virginica | L. | Caryophyllaceae | 8 |
| Silphium asteriscus | L. | Asteraceae | 8 |
| Silphium integrifolium | Michx. | Asteraceae | 8 |
| Silphium laciniatum | L. | Asteraceae | 8 |
| Silphium perfoliatum | L. | Asteraceae | 8 |
| Silphium radula | Nutt. | Asteraceae | 8 |
| Silphium terebinthinaceum | Jacq. | Asteraceae | 8 |
| Sisyrinchium albidum | Raf. | Iridaceae | 8 |
| Sisyrinchium angustifolium | Mill. | Iridaceae | 8 |
| Sisyrinchium atlanticum | E.P.Bicknell | Iridaceae | 8 |
| Sisyrinchium campestre | E.P.Bicknell | Iridaceae | 8 |
| Sisyrinchium fuscatum | E.P.Bicknell | Iridaceae | 8 |
| Sitobolium punctilobulum | (Michx.) Desv. | Dennstaedtiaceae | 8 |
| Sium suave | Walter | Apiaceae | 8 |
| Smallanthus uvedalia | (L.) Mack. | Asteraceae | 8 |
| Smilax bona-nox | L. | Smilacaceae | 8 |
| Smilax ecirrhata | (Engelm. ex Kunth) S.Watson | Smilacaceae | 8 |
| Smilax glauca | Walter | Smilacaceae | 8 |
| Smilax illinoensis | Mangaly | Smilacaceae | 8 |
| Smilax pulverulenta | Michx. | Smilacaceae | 8 |
| Smilax rotundifolia | L. | Smilacaceae | 8 |
| Smilax tamnoides | L. | Smilacaceae | 8 |
| Solanum carolinense | L. | Solanaceae | 8 |
| Solanum dimidiatum | Raf. | Solanaceae | 8 |
| Solanum emulans | Raf. | Solanaceae | 8 |
| Solanum rostratum | Dunal | Solanaceae | 8 |
| Solanum triflorum | Nutt. | Solanaceae | 8 |
| Solidago altissima | L. | Asteraceae | 8 |
| Solidago arguta | Aiton | Asteraceae | 8 |
| Solidago bicolor | L. | Asteraceae | 8 |
| Solidago caesia | L. | Asteraceae | 8 |
| Solidago flexicaulis | L. | Asteraceae | 8 |
| Solidago gigantea | Aiton | Asteraceae | 8 |
| Solidago hispida | Muhl. ex Willd. | Asteraceae | 8 |
| Solidago juncea | Aiton | Asteraceae | 8 |
| Solidago missouriensis | Nutt. | Asteraceae | 8 |
| Solidago nemoralis | Aiton | Asteraceae | 8 |
| Solidago odora | Aiton | Asteraceae | 8 |
| Solidago patula | Muhl. ex Willd. | Asteraceae | 8 |
| Solidago petiolaris | Aiton | Asteraceae | 8 |
| Solidago ptarmicoides | (Torr. & A.Gray) B.Boivin | Asteraceae | 8 |
| Solidago radula | Nutt. | Asteraceae | 8 |
| Solidago riddellii | Frank | Asteraceae | 8 |
| Solidago rigida | L. | Asteraceae | 8 |
| Solidago rigidiuscula | (Torr. & A.Gray) Porter | Asteraceae | 8 |
| Solidago rugosa | Mill. | Asteraceae | 8 |
| Solidago ulmifolia | Muhl. ex Willd. | Asteraceae | 8 |
| Sorghastrum nutans | (L.) Nash | Poaceae | 8 |
| Sparganium americanum | Nutt. | Typhaceae | 8 |
| Sparganium eurycarpum | Engelm. | Typhaceae | 8 |
| Spergularia marina | (L.) Besser | Caryophyllaceae | 8 |
| Spermacoce glabra | Michx. | Rubiaceae | 8 |
| Spermolepis inermis | (Nutt. ex DC.) Mathias & Constance | Apiaceae | 8 |
| Sphenopholis intermedia | (Rydb.) Rydb. | Poaceae | 8 |
| Sphenopholis nitida | (Biehler) Scribn. | Poaceae | 8 |
| Sphenopholis obtusata | (Michx.) Scribn. | Poaceae | 8 |
| Sphenopholis pensylvanica | (L.) Hitchc. | Poaceae | 8 |
| Spigelia marilandica | (L.) L. | Loganiaceae | 8 |
| Spiraea alba | Du Roi | Rosaceae | 8 |
| Spiraea tomentosa | L. | Rosaceae | 8 |
| Spiranthes cernua | (L.) Rich. | Orchidaceae | 8 |
| Spiranthes incurva | (Jenn.) M.C.Pace | Orchidaceae | 8 |
| Spiranthes lacera | (Raf.) Raf. | Orchidaceae | 8 |
| Spiranthes lucida | (H.H.Eaton) Ames | Orchidaceae | 8 |
| Spiranthes magnicamporum | Sheviak | Orchidaceae | 8 |
| Spiranthes ovalis | Lindl. | Orchidaceae | 8 |
| Spiranthes praecox | (Walter) S.Watson | Orchidaceae | 8 |
| Spiranthes tuberosa | Raf. | Orchidaceae | 8 |
| Spiranthes vernalis | Engelm. & A.Gray | Orchidaceae | 8 |
| Spirodela polyrhiza | (L.) Schleid. | Araceae | 8 |
| Sporobolus airoides | (Torr.) Torr. | Poaceae | 8 |
| Sporobolus clandestinus | (Biehler) Hitchc. | Poaceae | 8 |
| Sporobolus compositus | (Poir.) Merr. | Poaceae | 8 |
| Sporobolus cryptandrus | (Torr.) A.Gray | Poaceae | 8 |
| Sporobolus heterolepis | (A.Gray) A.Gray | Poaceae | 8 |
| Sporobolus michauxianus | (Hitchc.) P.M.Peterson & Saarela | Poaceae | 8 |
| Sporobolus neglectus | Nash | Poaceae | 8 |
| Sporobolus pyramidatus | (Lam.) Hitchc. | Poaceae | 8 |
| Sporobolus rigidus | (Buckley) P.M.Peterson | Poaceae | 8 |
| Sporobolus vaginiflorus | (Torr. ex A.Gray) Alph.Wood | Poaceae | 8 |
| Stachys aspera | Michx. | Lamiaceae | 8 |
| Stachys hispida | Pursh | Lamiaceae | 8 |
| Stachys pilosa | Nutt. | Lamiaceae | 8 |
| Stachys tenuifolia | Willd. | Lamiaceae | 8 |
| Steinchisma hians | (Elliott) Nash | Poaceae | 8 |
| Stellaria longifolia | Muhl. ex Willd. | Caryophyllaceae | 8 |
| Stenanthium gramineum | (Ker Gawl.) Morong | Melanthiaceae | 8 |
| Stenaria nigricans | (Lam.) Terrell | Rubiaceae | 8 |
| Strophostyles leiosperma | (Torr. & A.Gray) Piper | Fabaceae | 8 |
| Stuckenia pectinata | (L.) Börner | Potamogetonaceae | 8 |
| Stylisma pickeringii | (Torr. ex M.A.Curtis) A.Gray | Convolvulaceae | 8 |
| Stylophorum diphyllum | (Michx.) Nutt. | Papaveraceae | 8 |
| Stylosanthes biflora | (L.) Britton, Sterns & Poggenb. | Fabaceae | 8 |
| Styrax americanus | Lam. | Styracaceae | 8 |
| Suaeda calceoliformis | (Hook.) Moq. | Chenopodiaceae | 8 |
| Sullivantia sullivantii | (Torr. & A.Gray) Britton | Saxifragaceae | 8 |
| Symphoricarpos albus | (L.) S.F.Blake | Caprifoliaceae | 8 |
| Symphoricarpos occidentalis | (R.Br.) Hook. | Caprifoliaceae | 8 |
| Symphoricarpos orbiculatus | Moench | Caprifoliaceae | 8 |
| Symphyotrichum anomalum | (Engelm.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum ciliatum | (Ledeb.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum cordifolium | (L.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum drummondii | (Lindl.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum dumosum | (L.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum ericoides | (L.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum falcatum | (Lindl.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum firmum | (Nees) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum laeve | (L.) Á.Löve & D.Löve | Asteraceae | 8 |
| Symphyotrichum lanceolatum | (Willd.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum novae-angliae | (L.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum oblongifolium | (Nutt.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum ontarionis | (Wiegand) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum patens | (Aiton) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum pilosum | (Willd.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum praealtum | (Poir.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum racemosum | (Elliott) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum sericeum | (Vent.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum turbinellum | (Lindl.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum urophyllum | (Lindl.) G.L.Nesom | Asteraceae | 8 |
| Taenidia integerrima | (L.) Drude | Apiaceae | 8 |
| Taxodium distichum | (L.) Rich. | Cupressaceae | 8 |
| Tephrosia virginiana | (L.) Pers. | Fabaceae | 8 |
| Teucrium canadense | L. | Lamiaceae | 8 |
| Thalia dealbata | Fraser | Marantaceae | 8 |
| Thalictrum dasycarpum | Fisch., C.A.Mey. & Avé-Lall. | Ranunculaceae | 8 |
| Thalictrum dioicum | L. | Ranunculaceae | 8 |
| Thalictrum revolutum | DC. | Ranunculaceae | 8 |
| Thaspium barbinode | (Michx.) Nutt. | Apiaceae | 8 |
| Thaspium chapmanii | (J.M.Coult. & Rose) Small | Apiaceae | 8 |
| Thaspium trifoliatum | (L.) A.Gray | Apiaceae | 8 |
| Thelesperma filifolium | (Hook.) A.Gray | Asteraceae | 8 |
| Thelypteris palustris | Schott | Thelypteridaceae | 8 |
| Thyrsanthella difformis | (Walter) Pichon | Apocynaceae | 8 |
| Tidestromia lanuginosa | (Nutt.) Standl. | Amaranthaceae | 8 |
| Tilia americana | L. | Malvaceae | 8 |
| Tipularia discolor | (Pursh) Nutt. | Orchidaceae | 8 |
| Tiquilia nuttallii | (Hook.) A.T.Richardson | Ehretiaceae | 8 |
| Tomostima cuneifolia | (Nutt. ex Torr. & A.Gray) Al-Shehbaz, M.Koch & Jordon-Thaden | Brassicaceae | 8 |
| Tomostima reptans | (Lam.) Al-Shehbaz, M.Koch & Jordon-Thaden | Brassicaceae | 8 |
| Toxicodendron pubescens | Mill. | Anacardiaceae | 8 |
| Toxicodendron radicans | (L.) Kuntze | Anacardiaceae | 8 |
| Toxicoscordion nuttallii | (A.Gray) Rydb. | Melanthiaceae | 8 |
| Tradescantia bracteata | Small | Commelinaceae | 8 |
| Tradescantia ernestiana | E.S.Anderson & Woodson | Commelinaceae | 8 |
| Tradescantia hirsutiflora | Bush | Commelinaceae | 8 |
| Tradescantia ohiensis | Raf. | Commelinaceae | 8 |
| Tradescantia ozarkana | E.S.Anderson & Woodson | Commelinaceae | 8 |
| Tradescantia subaspera | Ker Gawl. | Commelinaceae | 8 |
| Tradescantia tharpii | E.S.Anderson & Woodson | Commelinaceae | 8 |
| Tradescantia virginiana | L. | Commelinaceae | 8 |
| Tragia betonicifolia | Nutt. | Euphorbiaceae | 8 |
| Tragia cordata | Michx. | Euphorbiaceae | 8 |
| Tragia ramosa | Torr. | Euphorbiaceae | 8 |
| Trautvetteria caroliniensis | (Walter) Vail | Ranunculaceae | 8 |
| Trepocarpus aethusae | Nutt. ex DC. | Apiaceae | 8 |
| Trianthema portulacastrum | L. | Aizoaceae | 8 |
| Trichogalium arkansanum | (A.Gray) Kadereit & Schneew. | Rubiaceae | 8 |
| Trichogalium boreale | (L.) Fourr. | Rubiaceae | 8 |
| Trichogalium circaezans | (Michx.) Kadereit & Schneew. | Rubiaceae | 8 |
| Trichophorum planifolium | (Spreng.) Palla | Cyperaceae | 8 |
| Tridens chapmanii | (Small) Chase | Poaceae | 8 |
| Tridens flavus | (L.) Hitchc. | Poaceae | 8 |
| Tridens strictus | (Nutt.) Nash | Poaceae | 8 |
| Tridentopsis mutica | (Torr.) P.M.Peterson | Poaceae | 8 |
| Trifolium reflexum | L. | Fabaceae | 8 |
| Trifolium stoloniferum | Muhl. | Fabaceae | 8 |
| Trillium flexipes | Raf. | Melanthiaceae | 8 |
| Trillium nivale | Riddell | Melanthiaceae | 8 |
| Trillium pusillum | Michx. | Melanthiaceae | 8 |
| Trillium recurvatum | L.C.Beck | Melanthiaceae | 8 |
| Trillium sessile | L. | Melanthiaceae | 8 |
| Trillium viride | L.C.Beck | Melanthiaceae | 8 |
| Trillium viridescens | Nutt. | Melanthiaceae | 8 |
| Triodanis holzingeri | McVaugh | Campanulaceae | 8 |
| Triodanis lamprosperma | McVaugh | Campanulaceae | 8 |
| Triodanis leptocarpa | Nieuwl. | Campanulaceae | 8 |
| Triodanis perfoliata | (L.) Nieuwl. | Campanulaceae | 8 |
| Triosteum angustifolium | L. | Caprifoliaceae | 8 |
| Triosteum aurantiacum | E.P.Bicknell | Caprifoliaceae | 8 |
| Triosteum perfoliatum | L. | Caprifoliaceae | 8 |
| Triphora trianthophoros | (Sw.) Rydb. | Orchidaceae | 8 |
| Triplasis purpurea | (Walter) Chapm. | Poaceae | 8 |
| Tripsacum dactyloides | (L.) L. | Poaceae | 8 |
| Turritis glabra | L. | Brassicaceae | 8 |
| Typha angustifolia | L. | Typhaceae | 8 |
| Typha domingensis | Pers. | Typhaceae | 8 |
| Typha latifolia | L. | Typhaceae | 8 |
| Ulmus alata | Michx. | Ulmaceae | 8 |
| Ulmus americana | L. | Ulmaceae | 8 |
| Ulmus rubra | Muhl. | Ulmaceae | 8 |
| Ulmus thomasii | Sarg. | Ulmaceae | 8 |
| Urochloa platyphylla | (Munro ex C.Wright) R.D.Webster | Poaceae | 8 |
| Urtica chamaedryoides | Pursh | Urticaceae | 8 |
| Urtica gracilis | Aiton | Urticaceae | 8 |
| Utricularia gibba | L. | Lentibulariaceae | 8 |
| Utricularia macrorhiza | Leconte | Lentibulariaceae | 8 |
| Utricularia minor | L. | Lentibulariaceae | 8 |
| Uvularia grandiflora | Sm. | Colchicaceae | 8 |
| Uvularia sessilifolia | L. | Colchicaceae | 8 |
| Vaccinium arboreum | Marshall | Ericaceae | 8 |
| Vaccinium corymbosum | L. | Ericaceae | 8 |
| Vaccinium pallidum | Aiton | Ericaceae | 8 |
| Vaccinium stamineum | L. | Ericaceae | 8 |
| Vallisneria americana | Michx. | Hydrocharitaceae | 8 |
| Verbena bipinnatifida | (Nutt.) Schauer | Verbenaceae | 8 |
| Verbena bracteata | Cav. ex Lag. & Rodr. | Verbenaceae | 8 |
| Verbena canadensis | (L.) Britton | Verbenaceae | 8 |
| Verbena halei | Small | Verbenaceae | 8 |
| Verbena hastata | L. | Verbenaceae | 8 |
| Verbena simplex | Lehm. | Verbenaceae | 8 |
| Verbena stricta | Vent. | Verbenaceae | 8 |
| Verbena urticifolia | L. | Verbenaceae | 8 |
| Verbesina alternifolia | (L.) Britton ex Kearney | Asteraceae | 8 |
| Verbesina helianthoides | Michx. | Asteraceae | 8 |
| Verbesina occidentalis | Walter | Asteraceae | 8 |
| Verbesina virginica | L. | Asteraceae | 8 |
| Vernonia arkansana | DC. | Asteraceae | 8 |
| Vernonia baldwinii | Torr. | Asteraceae | 8 |
| Vernonia fasciculata | Michx. | Asteraceae | 8 |
| Vernonia gigantea | (Walter) Trel. | Asteraceae | 8 |
| Vernonia missurica | Raf. | Asteraceae | 8 |
| Veronica americana | (Raf.) Schwein. ex Benth. | Plantaginaceae | 8 |
| Veronica catenata | Pennell | Plantaginaceae | 8 |
| Veronica peregrina | L. | Plantaginaceae | 8 |
| Veronica serpyllifolia | L. | Plantaginaceae | 8 |
| Veronicastrum virginicum | (L.) Farw. | Plantaginaceae | 8 |
| Viburnum dentatum | L. | Viburnaceae | 8 |
| Viburnum lentago | L. | Viburnaceae | 8 |
| Viburnum prunifolium | L. | Viburnaceae | 8 |
| Viburnum rafinesqueanum | Schult. | Viburnaceae | 8 |
| Viburnum recognitum | Fernald | Viburnaceae | 8 |
| Viburnum rufidulum | Raf. | Viburnaceae | 8 |
| Viburnum scabrellum | (Torr. & A.Gray) Chapm. | Viburnaceae | 8 |
| Vicia americana | Muhl. ex Willd. | Fabaceae | 8 |
| Vicia caroliniana | Walter | Fabaceae | 8 |
| Vicia ludoviciana | Nutt. | Fabaceae | 8 |
| Vicia minutiflora | D.Dietr. | Fabaceae | 8 |
| Viola affinis | Leconte | Violaceae | 8 |
| Viola cucullata | Aiton | Violaceae | 8 |
| Viola lanceolata | L. | Violaceae | 8 |
| Viola macloskeyi | F.E.Lloyd | Violaceae | 8 |
| Viola missouriensis | Greene | Violaceae | 8 |
| Viola nephrophylla | Greene | Violaceae | 8 |
| Viola palmata | L. | Violaceae | 8 |
| Viola pedata | L. | Violaceae | 8 |
| Viola pedatifida | G.Don | Violaceae | 8 |
| Viola pubescens | Aiton | Violaceae | 8 |
| Viola rafinesquei | Greene | Violaceae | 8 |
| Viola sagittata | Aiton | Violaceae | 8 |
| Viola sororia | Willd. | Violaceae | 8 |
| Viola striata | Aiton | Violaceae | 8 |
| Vitis aestivalis | Michx. | Vitaceae | 8 |
| Vitis cinerea | (Engelm.) Millardet | Vitaceae | 8 |
| Vitis palmata | Vahl | Vitaceae | 8 |
| Vitis riparia | Michx. | Vitaceae | 8 |
| Vitis rotundifolia | Michx. | Vitaceae | 8 |
| Vitis rupestris | Scheele | Vitaceae | 8 |
| Vitis vulpina | L. | Vitaceae | 8 |
| Waldsteinia fragarioides | (Michx.) Tratt. | Rosaceae | 8 |
| Wisteria frutescens | (L.) Poir. | Fabaceae | 8 |
| Wolffia borealis | (Engelm.) Landolt | Araceae | 8 |
| Wolffia brasiliensis | Wedd. | Araceae | 8 |
| Wolffia columbiana | H.Karst. | Araceae | 8 |
| Wolffiella gladiata | (Hegelm.) Hegelm. | Araceae | 8 |
| Woodsia obtusa | (Sw.) Torr. | Woodsiaceae | 8 |
| Xanthium orientale | L. | Asteraceae | 8 |
| Xanthium spinosum | L. | Asteraceae | 8 |
| Xanthium strumarium | L. | Asteraceae | 8 |
| Xyris torta | Sm. | Xyridaceae | 8 |
| Yucca arkansana | Trel. | Asparagaceae | 8 |
| Yucca flaccida | Haw. | Asparagaceae | 8 |
| Yucca glauca | Nutt. | Asparagaceae | 8 |
| Zannichellia palustris | L. | Potamogetonaceae | 8 |
| Zanthoxylum americanum | Mill. | Rutaceae | 8 |
| Zeltnera texensis | (Griseb.) G.Mans. ex J.S.Pringle | Gentianaceae | 8 |
| Zizania aquatica | L. | Poaceae | 8 |
| Zizania palustris | L. | Poaceae | 8 |
| Zizaniopsis miliacea | (Michx.) Döll & Asch. | Poaceae | 8 |
| Zizia aptera | (A.Gray) Fernald | Apiaceae | 8 |
| Carex reznicekii | Werier | Cyperaceae | 7 |
| Corispermum americanum | (Nutt.) Nutt. | Chenopodiaceae | 7 |
| Crataegus reverchonii | Sarg. | Rosaceae | 7 |
| Cyperus hortensis | (Salzm. ex Steud.) Dorr | Cyperaceae | 7 |
| Didiplis diandra | (Nutt. ex DC.) Alph.Wood | Lythraceae | 7 |
| Eleocharis brittonii | Svenson ex Small | Cyperaceae | 7 |
| Eriochloa acuminata | (J.Presl) Kunth | Poaceae | 7 |
| Festuca sciurea | Nutt. | Poaceae | 7 |
| Glyceria arkansana | Fernald | Poaceae | 7 |
| Hypericum adpressum | W.P.C.Barton | Hypericaceae | 7 |
| Isoetes melanopoda | J.Gay & Durieu | Isoetaceae | 7 |
| Sabulina muscorum | (Fassett) E.E.Schill. | Caryophyllaceae | 7 |
| Scirpus pallidus | (Britton) Fernald | Cyperaceae | 7 |
| Tradescantia longipes | E.S.Anderson & Woodson | Commelinaceae | 7 |
| Amaranthus arenicola | I.M.Johnst. | Amaranthaceae | 6 |
| Aristida basiramea | Vasey | Poaceae | 6 |
| Bacopa rotundifolia | (Michx.) Wettst. | Plantaginaceae | 6 |
| Calystegia macounii | (Greene) Brummitt | Convolvulaceae | 6 |
| Carex alata | Torr. | Cyperaceae | 6 |
| Carex conoidea | Willd. | Cyperaceae | 6 |
| Eragrostis capillaris | (L.) Nees | Poaceae | 6 |
| Flaveria campestris | J.R.Johnst. | Asteraceae | 6 |
| Juncus brachycephalus | (Engelm.) Buchenau | Juncaceae | 6 |
| Muhlenbergia sobolifera | (Muhl. ex Willd.) Trin. | Poaceae | 6 |
| Physalis missouriensis | Mack. & Bush | Solanaceae | 6 |
| Plantago pusilla | Nutt. | Plantaginaceae | 6 |
| Platanthera praeclara | Sheviak & M.L.Bowles | Orchidaceae | 6 |
| Polygonum ramosissimum | Michx. | Polygonaceae | 6 |
| Solidago drummondii | Torr. & A.Gray | Asteraceae | 6 |
| Sparganium androcladum | (Engelm.) Morong | Typhaceae | 6 |
| Stachys hyssopifolia | Michx. | Lamiaceae | 6 |
| Canavalia ensiformis | (L.) DC. | Fabaceae | 5 |
| Opuntia nemoralis | Griffiths | Cactaceae | 5 |
| Panicum philadelphicum | Bernh. ex Nees | Poaceae | 5 |
| Poa wolfii | Scribn. | Poaceae | 5 |
| Silene nivea | (Nutt.) Muhl. ex DC. | Caryophyllaceae | 5 |
| Carex laeviconica | Dewey | Cyperaceae | 4 |
| Carex molestiformis | Reznicek & Rothrock | Cyperaceae | 4 |
| Carex oligocarpa | Willd. | Cyperaceae | 4 |
| Carex timida | Naczi & B.A.Ford | Cyperaceae | 4 |
| Cyperus hemidrummondii | Goetgh. | Cyperaceae | 4 |
| Cyperus setigerus | Torr. & Hook. | Cyperaceae | 4 |
| Digitaria villosa | (Walter) Pers. | Poaceae | 4 |
| Helanthium tenellum | (Mart. ex Schult.f.) Britton | Alismataceae | 4 |
| Helianthus silphioides | Nutt. | Asteraceae | 4 |
| Heteranthera rotundifolia | (Kunth) Griseb. | Pontederiaceae | 4 |
| Isolepis pseudosetacea | (Daveau) Gand. | Cyperaceae | 4 |
| Juncus subcaudatus | (Engelm.) Coville & S.F.Blake | Juncaceae | 4 |
| Ludwigia polycarpa | Short & R.Peter | Onagraceae | 4 |
| Nemastylis nuttallii | Pickering ex R.C.Foster | Iridaceae | 4 |
| Pycnanthemum torreyi | Benth. | Lamiaceae | 4 |
| Rhynchospora stiletto | Naczi & Ciafré | Cyperaceae | 4 |
| Schoenoplectiella hallii | (A.Gray) Lye | Cyperaceae | 4 |
| Solidago buckleyi | Torr. & A.Gray | Asteraceae | 4 |
| Carex echinodes | (Fernald) P.Rothr., Reznicek & Hipp | Cyperaceae | 3 |
| Carex lupuliformis | Sartwell ex Dewey | Cyperaceae | 3 |
| Carex mesochorea | Mack. | Cyperaceae | 3 |
| Carex missouriensis | P.Rothr. & Reznicek | Cyperaceae | 3 |
| Carex oklahomensis | Mack. | Cyperaceae | 3 |
| Chenopodium desiccatum | A.Nelson | Chenopodiaceae | 3 |
| Crataegus texana | Buckley | Rosaceae | 3 |
| Erysimum inconspicuum | (S.Watson) MacMill. | Brassicaceae | 3 |
| Heteranthera missouriensis | C.N.Horn | Pontederiaceae | 3 |
| Leitneria pilosa | J.A.Schrad. & W.R.Graves | Simaroubaceae | 3 |
| Oenothera nutans | G.F.Atk. & Bartlett | Onagraceae | 3 |
| Potamogeton pulcher | Tuck. | Potamogetonaceae | 3 |
| Pteridium latiusculum | Hieron. | Dennstaedtiaceae | 3 |
| Solidago gattingeri | Chapm. ex A.Gray | Asteraceae | 3 |