| Abies balsamea | (L.) Mill. | Pinaceae | 8 |
| Acer negundo | L. | Sapindaceae | 8 |
| Acer spicatum | Lam. | Sapindaceae | 8 |
| Achillea alpina | L. | Asteraceae | 8 |
| Achillea millefolium | L. | Asteraceae | 8 |
| Acmispon americanus | (Nutt.) Rydb. | Fabaceae | 8 |
| Acorus calamus | L. | Acoraceae | 8 |
| Actaea rubra | (Aiton) Willd. | Ranunculaceae | 8 |
| Adlumia fungosa | (Aiton) Greene ex Britton, Sterns & Poggenb. | Papaveraceae | 8 |
| Adoxa moschatellina | L. | Viburnaceae | 8 |
| Agalinis aspera | (Douglas ex Benth.) Britton | Orobanchaceae | 8 |
| Agalinis gattingeri | (Small) Small ex Britton & A.Br. | Orobanchaceae | 8 |
| Agalinis purpurea | (L.) Pennell | Orobanchaceae | 8 |
| Agalinis tenuifolia | (Vahl) Raf. | Orobanchaceae | 8 |
| Agastache foeniculum | (Pursh) Kuntze | Lamiaceae | 8 |
| Agoseris glauca | (Pursh) Raf. | Asteraceae | 8 |
| Agrimonia gryposepala | Wallr. | Rosaceae | 8 |
| Agrimonia striata | Michx. | Rosaceae | 8 |
| Agrostis scabra | Willd. | Poaceae | 8 |
| Alisma gramineum | Lej. | Alismataceae | 8 |
| Alisma triviale | Pursh | Alismataceae | 8 |
| Allium schoenoprasum | L. | Amaryllidaceae | 8 |
| Allium stellatum | Nutt. ex Ker Gawl. | Amaryllidaceae | 8 |
| Allium textile | A.Nelson & J.F.Macbr. | Amaryllidaceae | 8 |
| Alnus alnobetula | (Ehrh.) K.Koch | Betulaceae | 8 |
| Alnus incana | (L.) Moench | Betulaceae | 8 |
| Alopecurus aequalis | Sobol. | Poaceae | 8 |
| Alopecurus carolinianus | Walter | Poaceae | 8 |
| Alopecurus magellanicus | Lam. | Poaceae | 8 |
| Ambrosia acanthicarpa | Hook. | Asteraceae | 8 |
| Ambrosia artemisiifolia | L. | Asteraceae | 8 |
| Ambrosia psilostachya | DC. | Asteraceae | 8 |
| Ambrosia trifida | L. | Asteraceae | 8 |
| Amelanchier alnifolia | (Nutt.) Nutt. ex M.Roem. | Rosaceae | 8 |
| Amelanchier humilis | Wiegand | Rosaceae | 8 |
| Amphicarpaea bracteata | (L.) Fernald | Fabaceae | 8 |
| Anaphalis margaritacea | (L.) Benth. & Hook.f. | Asteraceae | 8 |
| Andersonglossum boreale | (Fernald) Jim.Mejías, J.I.Cohen & Naczi | Boraginaceae | 8 |
| Andromeda polifolia | L. | Ericaceae | 8 |
| Andropogon hallii | Hack. | Poaceae | 8 |
| Androsace occidentalis | Pursh | Primulaceae | 8 |
| Androsace septentrionalis | L. | Primulaceae | 8 |
| Anemonastrum canadense | (L.) Mosyakin | Ranunculaceae | 8 |
| Anemonastrum richardsonii | (Hook.) Mosyakin | Ranunculaceae | 8 |
| Anemone cylindrica | A.Gray | Ranunculaceae | 8 |
| Anemone multifida | Poir. | Ranunculaceae | 8 |
| Anemone parviflora | Michx. | Ranunculaceae | 8 |
| Anemone quinquefolia | L. | Ranunculaceae | 8 |
| Anemone virginiana | L. | Ranunculaceae | 8 |
| Antennaria howellii | Greene | Asteraceae | 8 |
| Antennaria microphylla | Rydb. | Asteraceae | 8 |
| Antennaria neglecta | Greene | Asteraceae | 8 |
| Antennaria parlinii | Fernald | Asteraceae | 8 |
| Antennaria parvifolia | Nutt. | Asteraceae | 8 |
| Antennaria plantaginifolia | (L.) Richardson | Asteraceae | 8 |
| Antennaria pulcherrima | (Hook.) Greene | Asteraceae | 8 |
| Antennaria rosea | Greene | Asteraceae | 8 |
| Anthoxanthum monticola | (Bigelow) Veldkamp | Poaceae | 8 |
| Anthoxanthum nitens | (Weber) Y.Schouten & Veldkamp | Poaceae | 8 |
| Anticlea elegans | (Pursh) Rydb. | Melanthiaceae | 8 |
| Apocynum androsaemifolium | L. | Apocynaceae | 8 |
| Apocynum cannabinum | L. | Apocynaceae | 8 |
| Aquilegia brevistyla | Hook. | Ranunculaceae | 8 |
| Aquilegia canadensis | L. | Ranunculaceae | 8 |
| Arabidopsis lyrata | (L.) O'Kane & Al-Shehbaz | Brassicaceae | 8 |
| Aralia hispida | Vent. | Araliaceae | 8 |
| Aralia nudicaulis | L. | Araliaceae | 8 |
| Aralia racemosa | L. | Araliaceae | 8 |
| Arceuthobium americanum | Nutt. ex Engelm. | Santalaceae | 8 |
| Arctagrostis latifolia | (R.Br.) Griseb. | Poaceae | 8 |
| Arctostaphylos uva-ursi | (L.) Spreng. | Ericaceae | 8 |
| Arctous alpina | (L.) Nied. | Ericaceae | 8 |
| Arctous rubra | (Rehder & E.H.Wilson) Nakai | Ericaceae | 8 |
| Arethusa bulbosa | L. | Orchidaceae | 8 |
| Argentina anserina | (L.) Rydb. | Rosaceae | 8 |
| Arisaema triphyllum | (L.) Schott | Araceae | 8 |
| Armeria maritima | (Mill.) Willd. | Plumbaginaceae | 8 |
| Arnica angustifolia | Vahl | Asteraceae | 8 |
| Arnica chamissonis | Less. | Asteraceae | 8 |
| Arnica cordifolia | Hook. | Asteraceae | 8 |
| Arnica fulgens | Pursh | Asteraceae | 8 |
| Arnica lonchophylla | Greene | Asteraceae | 8 |
| Artemisia campestris | L. | Asteraceae | 8 |
| Artemisia cana | Pursh | Asteraceae | 8 |
| Artemisia dracunculus | L. | Asteraceae | 8 |
| Artemisia frigida | Willd. | Asteraceae | 8 |
| Artemisia longifolia | Nutt. | Asteraceae | 8 |
| Artemisia ludoviciana | Nutt. | Asteraceae | 8 |
| Artemisia tilesii | Ledeb. | Asteraceae | 8 |
| Asarum canadense | L. | Aristolochiaceae | 8 |
| Asclepias incarnata | L. | Apocynaceae | 8 |
| Asclepias ovalifolia | Decne. | Apocynaceae | 8 |
| Asclepias speciosa | Torr. | Apocynaceae | 8 |
| Asclepias syriaca | L. | Apocynaceae | 8 |
| Asclepias verticillata | L. | Apocynaceae | 8 |
| Asclepias viridiflora | Raf. | Apocynaceae | 8 |
| Astragalus agrestis | Douglas ex G.Don | Fabaceae | 8 |
| Astragalus alpinus | L. | Fabaceae | 8 |
| Astragalus americanus | (Hook.) M.E.Jones | Fabaceae | 8 |
| Astragalus bisulcatus | (Hook.) A.Gray | Fabaceae | 8 |
| Astragalus bodinii | E.Sheld. | Fabaceae | 8 |
| Astragalus canadensis | L. | Fabaceae | 8 |
| Astragalus crassicarpus | Nutt. | Fabaceae | 8 |
| Astragalus eucosmus | B.L.Rob. | Fabaceae | 8 |
| Astragalus flexuosus | (Hook.) Douglas ex G.Don | Fabaceae | 8 |
| Astragalus gilviflorus | E.Sheld. | Fabaceae | 8 |
| Astragalus laxmannii | Jacq. | Fabaceae | 8 |
| Astragalus lotiflorus | Hook. | Fabaceae | 8 |
| Astragalus missouriensis | Nutt. | Fabaceae | 8 |
| Astragalus multiflorus | (Pursh) A.Gray | Fabaceae | 8 |
| Astragalus neglectus | (Torr. & A.Gray) E.Sheld. | Fabaceae | 8 |
| Astragalus pectinatus | (Hook.) Douglas ex G.Don | Fabaceae | 8 |
| Athyrium angustum | (Willd.) C.Presl | Athyriaceae | 8 |
| Atriplex argentea | Nutt. | Chenopodiaceae | 8 |
| Atriplex patula | L. | Chenopodiaceae | 8 |
| Barbarea orthoceras | Ledeb. | Brassicaceae | 8 |
| Beckmannia syzigachne | (Steud.) Fernald | Poaceae | 8 |
| Betula glandulosa | Michx. | Betulaceae | 8 |
| Betula occidentalis | Hook. | Betulaceae | 8 |
| Betula papyrifera | Marshall | Betulaceae | 8 |
| Betula pendula | Roth | Betulaceae | 8 |
| Betula pumila | L. | Betulaceae | 8 |
| Bidens beckii | Torr. ex Spreng. | Asteraceae | 8 |
| Bidens cernua | L. | Asteraceae | 8 |
| Bidens frondosa | L. | Asteraceae | 8 |
| Bidens tripartita | L. | Asteraceae | 8 |
| Bidens vulgata | Greene | Asteraceae | 8 |
| Blitum capitatum | L. | Chenopodiaceae | 8 |
| Blitum nuttallianum | Schult. | Chenopodiaceae | 8 |
| Boechera grahamii | (Lehm.) Windham & Al-Shehbaz | Brassicaceae | 8 |
| Boechera retrofracta | (Graham) Á.Löve & D.Löve | Brassicaceae | 8 |
| Bolboschoenus fluviatilis | (Torr.) Soják | Cyperaceae | 8 |
| Bolboschoenus maritimus | (L.) Palla | Cyperaceae | 8 |
| Boltonia asteroides | L'Hér. | Asteraceae | 8 |
| Botrychium matricariifolium | (Retz.) A.Braun ex W.D.J.Koch | Ophioglossaceae | 8 |
| Botrychium minganense | Vict. | Ophioglossaceae | 8 |
| Botrychium pinnatum | H.St.John | Ophioglossaceae | 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 |
| Brasenia schreberi | J.F.Gmel. | Cabombaceae | 8 |
| Braya humilis | (C.A.Mey.) B.L.Rob. | Brassicaceae | 8 |
| Bromus ciliatus | L. | Poaceae | 8 |
| Bromus kalmii | A.Gray | Poaceae | 8 |
| Bromus latiglumis | (Shear) Hitchc. | Poaceae | 8 |
| Bromus porteri | (Coult.) Nash | Poaceae | 8 |
| Bromus pubescens | Muhl. ex Willd. | Poaceae | 8 |
| Bromus pumpellianus | Scribn. | Poaceae | 8 |
| Bromus sitchensis | Trin. | Poaceae | 8 |
| Calamagrostis canadensis | (Michx.) P.Beauv. | Poaceae | 8 |
| Calamagrostis inexpansa | A.Gray | Poaceae | 8 |
| Calamagrostis lapponica | (Wahlenb.) Hartm. | Poaceae | 8 |
| Calamagrostis montanensis | (Scribn.) Scribn. ex Vasey | Poaceae | 8 |
| Calamagrostis purpurascens | R.Br. | Poaceae | 8 |
| Calamagrostis purpurea | (Trin.) Trin. | Poaceae | 8 |
| Calamagrostis rubescens | Buckley | Poaceae | 8 |
| Calamagrostis stricta | (Timm) Koeler | Poaceae | 8 |
| Calla palustris | L. | Araceae | 8 |
| Callitriche heterophylla | Pursh | Plantaginaceae | 8 |
| Callitriche palustris | L. | Plantaginaceae | 8 |
| Calopogon tuberosus | (L.) Britton, Sterns & Poggenb. | Orchidaceae | 8 |
| Caltha palustris | L. | Ranunculaceae | 8 |
| Calypso bulbosa | (L.) Oakes | Orchidaceae | 8 |
| Calystegia sepium | (L.) R.Br. | Convolvulaceae | 8 |
| Campanula petiolata | A.DC. | Campanulaceae | 8 |
| Canadanthus modestus | (Lindl.) G.L.Nesom | Asteraceae | 8 |
| Capnoides sempervirens | (L.) Borkh. | Papaveraceae | 8 |
| Cardamine bulbosa | (Schreb. ex Muhl.) Britton, Sterns & Poggenb. | Brassicaceae | 8 |
| Cardamine parviflora | L. | Brassicaceae | 8 |
| Cardamine pensylvanica | Muhl. ex Willd. | Brassicaceae | 8 |
| Cardamine polemonioides | Rouy | Brassicaceae | 8 |
| Carex adusta | Boott | Cyperaceae | 8 |
| Carex alascana | Boeckeler | Cyperaceae | 8 |
| Carex alopecoidea | Tuck. | Cyperaceae | 8 |
| Carex aquatilis | Wahlenb. | Cyperaceae | 8 |
| Carex arctata | Boott | Cyperaceae | 8 |
| Carex atherodes | Spreng. | Cyperaceae | 8 |
| Carex athrostachya | Olney | Cyperaceae | 8 |
| Carex atratiformis | Britton | Cyperaceae | 8 |
| Carex aurea | Nutt. | Cyperaceae | 8 |
| Carex bebbii | (L.H.Bailey) Olney ex Fernald | Cyperaceae | 8 |
| Carex bicknellii | Britton & A.Br. | Cyperaceae | 8 |
| Carex bigelowii | Torr. ex Schwein. | Cyperaceae | 8 |
| Carex brevior | (Dewey) Mack. ex Lunell | Cyperaceae | 8 |
| Carex brunnescens | (Pers.) Poir. | Cyperaceae | 8 |
| Carex buxbaumii | Wahlenb. | Cyperaceae | 8 |
| Carex canescens | L. | Cyperaceae | 8 |
| Carex capillaris | L. | Cyperaceae | 8 |
| Carex capitata | Sol. | Cyperaceae | 8 |
| Carex castanea | Wahlenb. | Cyperaceae | 8 |
| Carex chordorrhiza | L.f. | Cyperaceae | 8 |
| Carex concinna | R.Br. | 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 cumulata | (L.H.Bailey) Mack. | Cyperaceae | 8 |
| Carex deflexa | Hornem. | Cyperaceae | 8 |
| Carex deweyana | Schwein. | Cyperaceae | 8 |
| Carex diandra | Schrank | Cyperaceae | 8 |
| Carex disperma | Dewey | Cyperaceae | 8 |
| Carex duriuscula | C.A.Mey. | Cyperaceae | 8 |
| Carex eburnea | Boott | Cyperaceae | 8 |
| Carex emoryi | Dewey | Cyperaceae | 8 |
| Carex filifolia | Nutt. | Cyperaceae | 8 |
| Carex flava | L. | Cyperaceae | 8 |
| Carex foenea | Willd. | Cyperaceae | 8 |
| Carex garberi | Fernald | Cyperaceae | 8 |
| Carex gracillima | Schwein. | Cyperaceae | 8 |
| Carex granularis | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex gravida | L.H.Bailey | Cyperaceae | 8 |
| Carex houghtoniana | Torr. ex Dewey | 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 lachenalii | Schkuhr | Cyperaceae | 8 |
| Carex lacustris | Willd. | Cyperaceae | 8 |
| Carex lasiocarpa | Ehrh. | Cyperaceae | 8 |
| Carex lenticularis | Michx. | Cyperaceae | 8 |
| Carex leptalea | Wahlenb. | Cyperaceae | 8 |
| Carex limosa | L. | Cyperaceae | 8 |
| Carex livida | (Wahlenb.) Willd. | Cyperaceae | 8 |
| Carex magellanica | Lam. | Cyperaceae | 8 |
| Carex meadii | Dewey | Cyperaceae | 8 |
| Carex media | R.Br. | Cyperaceae | 8 |
| Carex michauxiana | Boeckeler | Cyperaceae | 8 |
| Carex microglochin | Wahlenb. | Cyperaceae | 8 |
| Carex microptera | Mack. | Cyperaceae | 8 |
| Carex myosuroides | Vill. | Cyperaceae | 8 |
| Carex oligosperma | Michx. | Cyperaceae | 8 |
| Carex paleacea | Schreb. ex Wahlenb. | Cyperaceae | 8 |
| Carex pauciflora | Lightf. | Cyperaceae | 8 |
| Carex peckii | Howe | Cyperaceae | 8 |
| Carex pedunculata | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex pellita | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex pensylvanica | Lam. | Cyperaceae | 8 |
| Carex praegracilis | W.Boott | Cyperaceae | 8 |
| Carex prairea | Dewey ex Alph.Wood | Cyperaceae | 8 |
| Carex praticola | Rydb. | Cyperaceae | 8 |
| Carex projecta | Mack. | Cyperaceae | 8 |
| Carex pseudocyperus | L. | Cyperaceae | 8 |
| Carex radiata | (Wahlenb.) Small | Cyperaceae | 8 |
| Carex rariflora | (Wahlenb.) Sm. | Cyperaceae | 8 |
| Carex retrorsa | Schwein. | Cyperaceae | 8 |
| Carex richardsonii | R.Br. | Cyperaceae | 8 |
| Carex rosea | Willd. | Cyperaceae | 8 |
| Carex rossii | Boott | Cyperaceae | 8 |
| Carex rostrata | Stokes | Cyperaceae | 8 |
| Carex rotundata | Wahlenb. | Cyperaceae | 8 |
| Carex rupestris | All. | Cyperaceae | 8 |
| Carex sartwellii | Dewey | Cyperaceae | 8 |
| Carex scirpoidea | Michx. | Cyperaceae | 8 |
| Carex scoparia | Schkuhr ex Willd. | Cyperaceae | 8 |
| Carex siccata | Dewey | Cyperaceae | 8 |
| Carex simpliciuscula | Wahlenb. | Cyperaceae | 8 |
| Carex sprengelii | Dewey ex Spreng. | Cyperaceae | 8 |
| Carex sterilis | Willd. | Cyperaceae | 8 |
| Carex stipata | Muhl. ex Willd. | Cyperaceae | 8 |
| Carex supina | Willd. ex Wahlenb. | Cyperaceae | 8 |
| Carex sychnocephala | J.Carey | Cyperaceae | 8 |
| Carex tenera | Dewey | Cyperaceae | 8 |
| Carex tenuiflora | Wahlenb. | Cyperaceae | 8 |
| Carex tetanica | Schkuhr | Cyperaceae | 8 |
| Carex tonsa | (Fernald) E.P.Bicknell | Cyperaceae | 8 |
| Carex trisperma | Dewey | Cyperaceae | 8 |
| Carex utriculata | Boott | Cyperaceae | 8 |
| Carex vaginata | Tausch | Cyperaceae | 8 |
| Carex vesicaria | L. | Cyperaceae | 8 |
| Carex vulpinoidea | Michx. | Cyperaceae | 8 |
| Castilleja coccinea | (L.) Spreng. | Orobanchaceae | 8 |
| Castilleja elegans | Malte | Orobanchaceae | 8 |
| Castilleja miniata | Douglas ex Benth. | Orobanchaceae | 8 |
| Castilleja raupii | Pennell | Orobanchaceae | 8 |
| Castilleja sessiliflora | Pursh | Orobanchaceae | 8 |
| Catabrosa aquatica | (L.) P.Beauv. | Poaceae | 8 |
| Caulophyllum thalictroides | (L.) Michx. | Berberidaceae | 8 |
| Ceanothus herbaceus | Raf. | Rhamnaceae | 8 |
| Celastrus scandens | L. | Celastraceae | 8 |
| Celtis occidentalis | L. | Cannabaceae | 8 |
| Cerastium alpinum | L. | Caryophyllaceae | 8 |
| Cerastium beeringianum | Cham. & Schltdl. | Caryophyllaceae | 8 |
| Cerastium brachypodum | (Engelm. ex A.Gray) B.L.Rob. | Caryophyllaceae | 8 |
| Cerastium nutans | Raf. | Caryophyllaceae | 8 |
| Ceratophyllum demersum | L. | Ceratophyllaceae | 8 |
| Ceratophyllum echinatum | A.Gray | Ceratophyllaceae | 8 |
| Chamaedaphne calyculata | (L.) Moench | Ericaceae | 8 |
| Chamaerhodos erecta | (L.) Bunge | Rosaceae | 8 |
| Chasmanthium latifolium | (Michx.) H.O.Yates | Poaceae | 8 |
| Chelone glabra | L. | Plantaginaceae | 8 |
| Chenopodium berlandieri | Moq. | Chenopodiaceae | 8 |
| Chenopodium fremontii | S.Watson | Chenopodiaceae | 8 |
| Chenopodium rubrum | L. | Chenopodiaceae | 8 |
| Chimaphila umbellata | (L.) W.P.C.Barton | Ericaceae | 8 |
| Chrysopsis villosa | (Pursh) Nutt. ex DC. | Asteraceae | 8 |
| Chrysosplenium tetrandrum | (N.Lund) Th.Fr. | Saxifragaceae | 8 |
| Cicuta bulbifera | L. | Apiaceae | 8 |
| Cicuta maculata | L. | Apiaceae | 8 |
| Cicuta virosa | L. | Apiaceae | 8 |
| Cinna latifolia | (Trevir. ex Göpp.) Griseb. | Poaceae | 8 |
| Circaea alpina | L. | Onagraceae | 8 |
| Circaea canadensis | (L.) Hill | Onagraceae | 8 |
| Cirsium discolor | (Muhl. ex Willd.) Spreng. | Asteraceae | 8 |
| Cirsium drummondii | Torr. & A.Gray | Asteraceae | 8 |
| Cirsium flodmanii | Arthur | Asteraceae | 8 |
| Cirsium muticum | Michx. | Asteraceae | 8 |
| Cirsium undulatum | (Nutt.) Spreng. | Asteraceae | 8 |
| Cladium mariscoides | (Muhl.) Torr. | Cyperaceae | 8 |
| Claytosmunda claytoniana | (L.) Metzgar & Rouhan | Osmundaceae | 8 |
| Clematis ligusticifolia | Nutt. | Ranunculaceae | 8 |
| Clematis virginiana | L. | Ranunculaceae | 8 |
| Cleomella serrulata | (Pursh) Roalson & J.C.Hall | Cleomaceae | 8 |
| Clintonia borealis | (Aiton) Raf. | Liliaceae | 8 |
| Collinsia parviflora | Douglas ex Lindl. | Plantaginaceae | 8 |
| Collomia linearis | Nutt. | Polemoniaceae | 8 |
| Comandra umbellata | (L.) Nutt. | Santalaceae | 8 |
| Comarum palustre | L. | Rosaceae | 8 |
| Conopholis americana | (L.) Wallr. | Orobanchaceae | 8 |
| Coptis trifolia | (L.) Salisb. | Ranunculaceae | 8 |
| Corallorhiza maculata | Raf. | Orchidaceae | 8 |
| Corallorhiza striata | Lindl. | Orchidaceae | 8 |
| Corallorhiza trifida | Châtel. | Orchidaceae | 8 |
| Coreopsis tinctoria | Nutt. | Asteraceae | 8 |
| Cornus alternifolia | L.f. | Cornaceae | 8 |
| Cornus canadensis | L. | Cornaceae | 8 |
| Cornus racemosa | Lam. | Cornaceae | 8 |
| Cornus rugosa | Lam. | Cornaceae | 8 |
| Cornus sericea | L. | Cornaceae | 8 |
| Cornus suecica | L. | Cornaceae | 8 |
| Corydalis aurea | Willd. | Papaveraceae | 8 |
| Corylus americana | Walter | Betulaceae | 8 |
| Corylus cornuta | Marshall | Betulaceae | 8 |
| Crataegus chrysocarpa | Ashe | Rosaceae | 8 |
| Crataegus macracantha | (Lindl.) Lodd. ex Loudon | Rosaceae | 8 |
| Crocanthemum bicknellii | (Fernald) Janch. | Cistaceae | 8 |
| Cryptogramma acrostichoides | R.Br. | Pteridaceae | 8 |
| Cryptotaenia canadensis | (L.) DC. | Apiaceae | 8 |
| Cuscuta campestris | Yunck. | Convolvulaceae | 8 |
| Cuscuta cephalanthi | Engelm. | Convolvulaceae | 8 |
| Cuscuta coryli | Engelm. | Convolvulaceae | 8 |
| Cuscuta gronovii | Willd. | Convolvulaceae | 8 |
| Cuscuta pentagona | Engelm. | Convolvulaceae | 8 |
| Cymopterus glomeratus | (Nutt.) DC. | Apiaceae | 8 |
| Cyperus schweinitzii | Torr. | Cyperaceae | 8 |
| Cyperus squarrosus | L. | Cyperaceae | 8 |
| Cyperus strigosus | L. | Cyperaceae | 8 |
| Cypripedium acaule | Aiton | Orchidaceae | 8 |
| Cypripedium arietinum | R.Br. | Orchidaceae | 8 |
| Cypripedium candidum | Muhl. ex Willd. | Orchidaceae | 8 |
| Cypripedium parviflorum | Salisb. | Orchidaceae | 8 |
| Cypripedium passerinum | Richardson | Orchidaceae | 8 |
| Cypripedium reginae | Walter | Orchidaceae | 8 |
| Cystopteris fragilis | (L.) Bernh. | Cystopteridaceae | 8 |
| Dactylorhiza viridis | (L.) R.M.Bateman, Pridgeon & M.W.Chase | Orchidaceae | 8 |
| Dalea candida | Willd. | Fabaceae | 8 |
| Dalea villosa | (Nutt.) Spreng. | Fabaceae | 8 |
| Danthonia intermedia | Vasey | Poaceae | 8 |
| Danthonia spicata | (L.) Roem. & Schult. | Poaceae | 8 |
| Dasiphora fruticosa | (L.) Rydb. | Rosaceae | 8 |
| Delphinium carolinianum | Walter | Ranunculaceae | 8 |
| Delphinium glaucum | S.Watson | Ranunculaceae | 8 |
| Dendrolycopodium dendroideum | (Michx.) A.Haines | Lycopodiaceae | 8 |
| Dendrolycopodium hickeyi | (W.H.Wagner, Beitel & R.C.Moran) A.Haines | Lycopodiaceae | 8 |
| Descurainia incana | (Bernh. ex Fisch. & C.A.Mey.) Dorn | Brassicaceae | 8 |
| Descurainia pinnata | (Walter) Britton | Brassicaceae | 8 |
| Descurainia sophioides | (Fisch.) O.E.Schulz | Brassicaceae | 8 |
| Diapensia lapponica | L. | Diapensiaceae | 8 |
| Dichanthelium depauperatum | (Muhl.) Gould | Poaceae | 8 |
| Dichanthelium lanuginosum | (Elliott) Gould | Poaceae | 8 |
| Dichanthelium leibergii | (Vasey) Freckmann | Poaceae | 8 |
| Dichanthelium lindheimeri | (Nash) Gould | Poaceae | 8 |
| Dichanthelium linearifolium | (Scribn.) Gould | Poaceae | 8 |
| Dichanthelium xanthophysum | (A.Gray) Freckmann | Poaceae | 8 |
| Diervilla lonicera | Mill. | Caprifoliaceae | 8 |
| Diphasiastrum alpinum | (L.) Holub | Lycopodiaceae | 8 |
| Diphasiastrum complanatum | (L.) Holub | Lycopodiaceae | 8 |
| Diphasiastrum sitchense | (Rupr.) Holub | Lycopodiaceae | 8 |
| Diphasiastrum tristachyum | (Pursh) Holub | Lycopodiaceae | 8 |
| Distichlis spicata | (L.) Greene | Poaceae | 8 |
| Doellingeria umbellata | (Mill.) Nees | Asteraceae | 8 |
| Draba arabisans | Michx. | Brassicaceae | 8 |
| Draba aurea | Vahl ex Hornem. | Brassicaceae | 8 |
| Draba cana | Rydb. | Brassicaceae | 8 |
| Draba glabella | Pursh | Brassicaceae | 8 |
| Draba nemorosa | L. | Brassicaceae | 8 |
| Dracocephalum parviflorum | Nutt. | Lamiaceae | 8 |
| Drosera anglica | Huds. | Droseraceae | 8 |
| Drosera intermedia | Hayne | Droseraceae | 8 |
| Drosera linearis | Goldie | Droseraceae | 8 |
| Drosera rotundifolia | L. | Droseraceae | 8 |
| Dryas integrifolia | Vahl | Rosaceae | 8 |
| Drymocallis arguta | (Pursh) Rydb. | Rosaceae | 8 |
| Dryopteris carthusiana | (Vill.) H.P.Fuchs | Dryopteridaceae | 8 |
| Dryopteris cristata | (L.) A.Gray | Dryopteridaceae | 8 |
| Dryopteris fragrans | (L.) Schott | Dryopteridaceae | 8 |
| Dulichium arundinaceum | (L.) Britton | Cyperaceae | 8 |
| Echinacea angustifolia | DC. | Asteraceae | 8 |
| Echinochloa muricata | (P.Beauv.) Fernald | Poaceae | 8 |
| Echinocystis lobata | (Michx.) Torr. & A.Gray | Cucurbitaceae | 8 |
| Elaeagnus commutata | Bernh. ex Rydb. | Elaeagnaceae | 8 |
| Elatine americana | (Pursh) Arn. | Elatinaceae | 8 |
| Eleocharis acicularis | (L.) Roem. & Schult. | Cyperaceae | 8 |
| Eleocharis compressa | Sull. | Cyperaceae | 8 |
| Eleocharis elliptica | Kunth | Cyperaceae | 8 |
| Eleocharis engelmannii | Steud. | Cyperaceae | 8 |
| Eleocharis erythropoda | Steud. | Cyperaceae | 8 |
| Eleocharis macrostachya | Britton | Cyperaceae | 8 |
| Eleocharis palustris | (L.) Roem. & Schult. | Cyperaceae | 8 |
| Eleocharis quinqueflora | (Hartmann) O.Schwarz | Cyperaceae | 8 |
| Eleocharis uniglumis | (Link) Schult. | Cyperaceae | 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 lanceolatus | (Scribn. & J.G.Sm.) Gould | Poaceae | 8 |
| Elymus smithii | (Rydb.) Gould | Poaceae | 8 |
| Elymus violaceus | (Hornem.) J.Feilberg | Poaceae | 8 |
| Elymus virginicus | L. | Poaceae | 8 |
| Empetrum nigrum | L. | Ericaceae | 8 |
| Epigaea repens | L. | Ericaceae | 8 |
| Epilobium angustifolium | L. | Onagraceae | 8 |
| Epilobium brachycarpum | C.Presl | Onagraceae | 8 |
| Epilobium ciliatum | Raf. | Onagraceae | 8 |
| Epilobium latifolium | L. | Onagraceae | 8 |
| Epilobium leptophyllum | Raf. | Onagraceae | 8 |
| Epilobium palustre | L. | Onagraceae | 8 |
| Equisetum arvense | L. | Equisetaceae | 8 |
| Equisetum fluviatile | L. | Equisetaceae | 8 |
| Equisetum hyemale | L. | Equisetaceae | 8 |
| Equisetum laevigatum | A.Braun | Equisetaceae | 8 |
| Equisetum palustre | L. | Equisetaceae | 8 |
| Equisetum pratense | Ehrh. | Equisetaceae | 8 |
| Equisetum scirpoides | Michx. | Equisetaceae | 8 |
| Equisetum sylvaticum | L. | Equisetaceae | 8 |
| Equisetum variegatum | Schleich. ex F.Weber & D.Mohr | Equisetaceae | 8 |
| Eragrostis hypnoides | (Lam.) Britton, Sterns & Poggenb. | Poaceae | 8 |
| Eragrostis spectabilis | (Pursh) Steud. | Poaceae | 8 |
| Erigeron acris | L. | Asteraceae | 8 |
| Erigeron annuus | (L.) Desf. | Asteraceae | 8 |
| Erigeron caespitosus | Nutt. | Asteraceae | 8 |
| Erigeron canadensis | L. | Asteraceae | 8 |
| Erigeron glabellus | Nutt. | Asteraceae | 8 |
| Erigeron humilis | Graham | Asteraceae | 8 |
| Erigeron hyssopifolius | Michx. | Asteraceae | 8 |
| Erigeron lonchophyllus | Hook. | Asteraceae | 8 |
| Erigeron philadelphicus | L. | Asteraceae | 8 |
| Erigeron strigosus | Muhl. ex Willd. | Asteraceae | 8 |
| Eriocoma hymenoides | (Roem. & Schult.) Rydb. | Poaceae | 8 |
| Eriocoma richardsonii | (Link) Romasch. | Poaceae | 8 |
| Eriogonum flavum | Nutt. | Polygonaceae | 8 |
| Eriogonum pauciflorum | Pursh | Polygonaceae | 8 |
| Eriophorum angustifolium | Honck. | Cyperaceae | 8 |
| Eriophorum brachyantherum | Trautv. & C.A.Mey. | Cyperaceae | 8 |
| Eriophorum chamissonis | C.A.Mey. | Cyperaceae | 8 |
| Eriophorum gracile | Roth | Cyperaceae | 8 |
| Eriophorum scheuchzeri | Hoppe | Cyperaceae | 8 |
| Eriophorum vaginatum | L. | Cyperaceae | 8 |
| Eriophorum viridicarinatum | (Engelm.) Fernald | Cyperaceae | 8 |
| Erysimum asperum | (Nutt.) DC. | Brassicaceae | 8 |
| Erythranthe geyeri | (Torr.) G.L.Nesom | Phrymaceae | 8 |
| Eupatorium perfoliatum | L. | Asteraceae | 8 |
| Euphorbia geyeri | Engelm. | Euphorbiaceae | 8 |
| Euphorbia glyptosperma | Engelm. | Euphorbiaceae | 8 |
| Euphorbia serpillifolia | Pers. | Euphorbiaceae | 8 |
| Euphrasia subarctica | Raup | Orobanchaceae | 8 |
| Eurybia conspicua | (Lindl.) G.L.Nesom | Asteraceae | 8 |
| Eurybia macrophylla | (L.) Cass. | Asteraceae | 8 |
| Euthamia graminifolia | (L.) Nutt. | Asteraceae | 8 |
| Eutrema salsugineum | (Pall.) Al-Shehbaz & Warwick | Brassicaceae | 8 |
| Eutrochium maculatum | (L.) E.E.Lamont | Asteraceae | 8 |
| Fallopia scandens | (L.) Holub | Polygonaceae | 8 |
| Festuca brachyphylla | Schult. & Schult.f. | Poaceae | 8 |
| Festuca octoflora | Walter | Poaceae | 8 |
| Festuca rubra | L. | Poaceae | 8 |
| Festuca subverticillata | (Pers.) E.B.Alexeev | Poaceae | 8 |
| Fragaria vesca | L. | Rosaceae | 8 |
| Fragaria virginiana | Mill. | Rosaceae | 8 |
| Fraxinus pennsylvanica | Marshall | Oleaceae | 8 |
| Gaillardia aristata | Pursh | Asteraceae | 8 |
| Galearis rotundifolia | (Banks ex Pursh) R.M.Bateman | Orchidaceae | 8 |
| Galium spurium | L. | Rubiaceae | 8 |
| Galium trifidum | L. | Rubiaceae | 8 |
| Galium triflorum | Michx. | Rubiaceae | 8 |
| Gaultheria hispidula | (L.) Muhl. ex Bigelow | Ericaceae | 8 |
| Gaultheria procumbens | L. | Ericaceae | 8 |
| Gaylussacia baccata | (Wangenh.) K.Koch | Ericaceae | 8 |
| Gentiana affinis | Griseb. | Gentianaceae | 8 |
| Gentiana andrewsii | Griseb. | Gentianaceae | 8 |
| Gentiana puberulenta | J.S.Pringle | Gentianaceae | 8 |
| Gentiana rubricaulis | Schwein. | Gentianaceae | 8 |
| Gentianella propinqua | (Richardson) J.M.Gillett | Gentianaceae | 8 |
| Gentianopsis crinita | (Froel.) Ma | Gentianaceae | 8 |
| Gentianopsis virgata | (Raf.) Holub | Gentianaceae | 8 |
| Geocaulon lividum | (Richardson) Fernald | Santalaceae | 8 |
| Geranium bicknellii | Britton | Geraniaceae | 8 |
| Geranium carolinianum | L. | Geraniaceae | 8 |
| Geranium maculatum | L. | Geraniaceae | 8 |
| Geum aleppicum | Jacq. | Rosaceae | 8 |
| Geum canadense | Jacq. | Rosaceae | 8 |
| Geum macrophyllum | Willd. | Rosaceae | 8 |
| Geum rivale | L. | Rosaceae | 8 |
| Geum triflorum | Pursh | Rosaceae | 8 |
| Glyceria borealis | (Nash) Batch. | Poaceae | 8 |
| Glyceria canadensis | (Michx.) Trin. | Poaceae | 8 |
| Glyceria grandis | S.Watson | Poaceae | 8 |
| Glyceria striata | (Lam.) Hitchc. | Poaceae | 8 |
| Glycyrrhiza lepidota | Pursh | Fabaceae | 8 |
| Gnaphalium uliginosum | L. | Asteraceae | 8 |
| Goodyera repens | (L.) R.Br. | Orchidaceae | 8 |
| Goodyera tesselata | G.Lodd. | Orchidaceae | 8 |
| Gratiola neglecta | Torr. | Plantaginaceae | 8 |
| Grindelia hirsutula | Hook. & Arn. | Asteraceae | 8 |
| Grindelia squarrosa | (Pursh) Dunal | Asteraceae | 8 |
| Gutierrezia sarothrae | (Pursh) Britton & Rusby | Asteraceae | 8 |
| Gymnocarpium continentale | (Petrov.) Pojark. | Cystopteridaceae | 8 |
| Gymnocarpium dryopteris | (L.) Newman | Cystopteridaceae | 8 |
| Gymnocarpium robertianum | (Hoffm.) Newman | Cystopteridaceae | 8 |
| Hackelia deflexa | (Wahlenb.) Opiz | Boraginaceae | 8 |
| Hackelia floribunda | (Lehm.) I.M.Johnst. | Boraginaceae | 8 |
| Halenia deflexa | (Sm.) Griseb. | Gentianaceae | 8 |
| Halerpestes cymbalaria | Greene | Ranunculaceae | 8 |
| Hammarbya paludosa | (L.) Kuntze | Orchidaceae | 8 |
| Hedysarum alpinum | L. | Fabaceae | 8 |
| Hedysarum boreale | Nutt. | Fabaceae | 8 |
| Helenium autumnale | L. | Asteraceae | 8 |
| Helianthus maximiliani | Schrad. | Asteraceae | 8 |
| Helianthus nuttallii | Torr. & A.Gray | Asteraceae | 8 |
| Helianthus pauciflorus | Nutt. | Asteraceae | 8 |
| Helianthus petiolaris | Nutt. | Asteraceae | 8 |
| Helianthus tuberosus | L. | Asteraceae | 8 |
| Helictochloa hookeri | (Scribn.) Romero Zarco | Poaceae | 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 comata | (Trin. & Rupr.) Barkworth | Poaceae | 8 |
| Hesperostipa curtiseta | (Hitchc.) Barkworth | Poaceae | 8 |
| Hesperostipa spartea | (Trin.) Barkworth | Poaceae | 8 |
| Heteranthera dubia | (Jacq.) MacMill. | Pontederiaceae | 8 |
| Heuchera richardsonii | R.Br. | Saxifragaceae | 8 |
| Hieracium umbellatum | L. | Asteraceae | 8 |
| Hippuris vulgaris | L. | Plantaginaceae | 8 |
| Honckenya peploides | (L.) Ehrh. | Caryophyllaceae | 8 |
| Hordeum jubatum | L. | Poaceae | 8 |
| Houstonia longifolia | Gaertn. | Rubiaceae | 8 |
| Hudsonia tomentosa | Nutt. | Cistaceae | 8 |
| Humulus americanus | Nutt. | Cannabaceae | 8 |
| Humulus neomexicanus | (A.Nelson & Cockerell) Rydb. | Cannabaceae | 8 |
| Huperzia continentalis | Testo, A.Haines & A.V.Gilman | Lycopodiaceae | 8 |
| Huperzia lucidula | (Michx.) Trevis. | Lycopodiaceae | 8 |
| Huperzia selago | (L.) Bernh. ex Schrank & Mart. | Lycopodiaceae | 8 |
| Hydrogalium labradoricum | (Wiegand) Kadereit & Schneew. | Rubiaceae | 8 |
| Hydrophyllum virginianum | L. | Hydrophyllaceae | 8 |
| Hypericum boreale | (Britton) E.P.Bicknell | Hypericaceae | 8 |
| Hypericum fraseri | (Spach) Steud. | Hypericaceae | 8 |
| Hypericum majus | (A.Gray) Britton | Hypericaceae | 8 |
| Hypoxis hirsuta | (L.) Coville | Hypoxidaceae | 8 |
| Impatiens capensis | Meerb. | Balsaminaceae | 8 |
| Impatiens noli-tangere | L. | Balsaminaceae | 8 |
| Iris versicolor | L. | Iridaceae | 8 |
| Isoetes echinospora | Durieu | Isoetaceae | 8 |
| Iva axillaris | Pursh | Asteraceae | 8 |
| Juncus alpinoarticulatus | Chaix | Juncaceae | 8 |
| Juncus arcticus | Willd. | Juncaceae | 8 |
| Juncus balticus | Willd. | Juncaceae | 8 |
| Juncus bufonius | L. | Juncaceae | 8 |
| Juncus canadensis | J.Gay ex Laharpe | Juncaceae | 8 |
| Juncus castaneus | Sm. | Juncaceae | 8 |
| Juncus dudleyi | Wiegand | Juncaceae | 8 |
| Juncus effusus | L. | Juncaceae | 8 |
| Juncus filiformis | L. | Juncaceae | 8 |
| Juncus gerardi | Loisel. | Juncaceae | 8 |
| Juncus interior | Wiegand | Juncaceae | 8 |
| Juncus nodosus | L. | Juncaceae | 8 |
| Juncus torreyi | Coville | Juncaceae | 8 |
| Juncus tweedyi | Rydb. | Juncaceae | 8 |
| Juniperus horizontalis | Moench | Cupressaceae | 8 |
| Kalmia microphylla | (Hook.) A.Heller | Ericaceae | 8 |
| Kalmia polifolia | Wangenh. | Ericaceae | 8 |
| Kalmia procumbens | (L.) Gift, Kron & P.F.Stevens ex Galasso, Banfi & F.Conti | Ericaceae | 8 |
| Koeleria macrantha | (Ledeb.) Schult. | Poaceae | 8 |
| Koeleria spicata | (L.) Barberá, Quintanar, Soreng & P.M.Peterson | Poaceae | 8 |
| Krascheninnikovia ceratoides | (L.) Gueldenst. | Chenopodiaceae | 8 |
| Krigia biflora | (Walter) S.F.Blake | Asteraceae | 8 |
| Lactuca biennis | (Moench) Fernald | Asteraceae | 8 |
| Lactuca canadensis | L. | Asteraceae | 8 |
| Lactuca floridana | (L.) Gaertn. | Asteraceae | 8 |
| Lactuca ludoviciana | (Nutt.) Riddell | Asteraceae | 8 |
| Lactuca oblongifolia | Nutt. | Asteraceae | 8 |
| Laportea canadensis | (L.) Wedd. | Urticaceae | 8 |
| Lappula occidentalis | (S.Watson) Greene | Boraginaceae | 8 |
| Larix laricina | (Du Roi) K.Koch | Pinaceae | 8 |
| Lathyrus japonicus | Willd. | Fabaceae | 8 |
| Lathyrus ochroleucus | Hook. | Fabaceae | 8 |
| Lathyrus palustris | L. | Fabaceae | 8 |
| Lathyrus venosus | Muhl. ex Willd. | Fabaceae | 8 |
| Lechea intermedia | Legg. ex Britton | Cistaceae | 8 |
| Leersia oryzoides | (L.) Sw. | Poaceae | 8 |
| Lemna minor | L. | Araceae | 8 |
| Lemna trisulca | L. | Araceae | 8 |
| Lemna turionifera | Landolt | Araceae | 8 |
| Lepidium densiflorum | Schrad. | Brassicaceae | 8 |
| Leymus innovatus | (Beal) Pilg. | Poaceae | 8 |
| Leymus mollis | (Trin.) Pilg. | Poaceae | 8 |
| Liatris ligulistylis | (A.Nelson) K.Schum. | Asteraceae | 8 |
| Liatris punctata | Hook. | Asteraceae | 8 |
| Lilium philadelphicum | L. | Liliaceae | 8 |
| Limosella aquatica | L. | Plantaginaceae | 8 |
| Linnaea borealis | L. | Caprifoliaceae | 8 |
| Linum lewisii | Pursh | Linaceae | 8 |
| Linum rigidum | Pursh | Linaceae | 8 |
| Linum sulcatum | Riddell | Linaceae | 8 |
| Liparis loeselii | (L.) Rich. | Orchidaceae | 8 |
| Lithospermum canescens | Lehm. | Boraginaceae | 8 |
| Lithospermum incisum | Lehm. | Boraginaceae | 8 |
| Lithospermum occidentale | (Mack.) Weakley, Witsell & D.Estes | Boraginaceae | 8 |
| Lobelia dortmanna | L. | Campanulaceae | 8 |
| Lobelia kalmii | L. | 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 |
| Lomatogonium rotatum | (L.) Fernald | Gentianaceae | 8 |
| Lonicera caerulea | L. | Caprifoliaceae | 8 |
| Lonicera dioica | L. | Caprifoliaceae | 8 |
| Lonicera involucrata | (Richardson) Banks ex Spreng. | Caprifoliaceae | 8 |
| Lonicera oblongifolia | Hook. | Caprifoliaceae | 8 |
| Luzula acuminata | Raf. | Juncaceae | 8 |
| Luzula multiflora | (Ehrh.) Lej. | Juncaceae | 8 |
| Luzula parviflora | (Ehrh.) Desv. | Juncaceae | 8 |
| Luzula spicata | (L.) DC. | Juncaceae | 8 |
| Lycopodiella inundata | (L.) Holub | Lycopodiaceae | 8 |
| Lycopodium clavatum | L. | Lycopodiaceae | 8 |
| Lycopodium lagopus | Zinserl. ex Kuzen. | Lycopodiaceae | 8 |
| Lycopus americanus | Muhl. ex W.P.C.Barton | Lamiaceae | 8 |
| Lycopus asper | Greene | Lamiaceae | 8 |
| Lycopus uniflorus | Michx. | Lamiaceae | 8 |
| Lygodesmia juncea | (Pursh) Sweet | Asteraceae | 8 |
| Lysimachia borealis | (Raf.) U.Manns & Anderb. | Primulaceae | 8 |
| Lysimachia ciliata | L. | Primulaceae | 8 |
| Lysimachia hybrida | Michx. | Primulaceae | 8 |
| Lysimachia lanceolata | Walter | Primulaceae | 8 |
| Lysimachia maritima | (L.) Galasso, Banfi & Soldano | Primulaceae | 8 |
| Lysimachia quadriflora | Sims | Primulaceae | 8 |
| Lysimachia terrestris | (L.) Britton, Sterns & Poggenb. | Primulaceae | 8 |
| Lysimachia thyrsiflora | L. | Primulaceae | 8 |
| Madia glomerata | Hook. | Asteraceae | 8 |
| Maianthemum canadense | Desf. | Asparagaceae | 8 |
| Maianthemum racemosum | (L.) Link | Asparagaceae | 8 |
| Maianthemum stellatum | (L.) Link | Asparagaceae | 8 |
| Maianthemum trifolium | (L.) Sloboda | Asparagaceae | 8 |
| Malaxis monophyllos | (L.) Sw. | Orchidaceae | 8 |
| Malaxis unifolia | Michx. | Orchidaceae | 8 |
| Matricaria discoidea | DC. | Asteraceae | 8 |
| Menispermum canadense | L. | Menispermaceae | 8 |
| Mentha canadensis | L. | Lamiaceae | 8 |
| Mentzelia decapetala | (Sims) Urb. | Loasaceae | 8 |
| Menyanthes trifoliata | L. | Menyanthaceae | 8 |
| Mertensia lanceolata | (Pursh) DC. | Boraginaceae | 8 |
| Mertensia maritima | (L.) Gray | Boraginaceae | 8 |
| Micranthes pensylvanica | (L.) Haw. | Saxifragaceae | 8 |
| Micranthes virginiensis | Small | Saxifragaceae | 8 |
| Milium effusum | L. | Poaceae | 8 |
| Mimulus ringens | L. | Phrymaceae | 8 |
| Mirabilis albida | (Walter) Heimerl | Nyctaginaceae | 8 |
| Mirabilis linearis | (Pursh) Heimerl | Nyctaginaceae | 8 |
| Mitella nuda | L. | Saxifragaceae | 8 |
| Moehringia lateriflora | (L.) Fenzl | Caryophyllaceae | 8 |
| Moehringia macrophylla | (Hook.) Fenzl | Caryophyllaceae | 8 |
| Mollugo verticillata | L. | Molluginaceae | 8 |
| Monarda fistulosa | L. | Lamiaceae | 8 |
| Moneses uniflora | (L.) A.Gray | Ericaceae | 8 |
| Monotropa uniflora | L. | Ericaceae | 8 |
| Montia fontana | L. | Montiaceae | 8 |
| Muhlenbergia asperifolia | (Nees & Meyen ex Trin.) Parodi | Poaceae | 8 |
| Muhlenbergia cuspidata | (Torr. ex Hook.) Rydb. | Poaceae | 8 |
| Muhlenbergia glomerata | (Willd.) Trin. | 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 richardsonis | (Trin.) Rydb. | Poaceae | 8 |
| Munroa squarrosa | (Nutt.) Torr. | Poaceae | 8 |
| Musineon divaricatum | (Pursh) Nutt. | Apiaceae | 8 |
| Myrica gale | L. | Myricaceae | 8 |
| Myriophyllum alterniflorum | DC. | Haloragaceae | 8 |
| Myriophyllum farwellii | Morong | Haloragaceae | 8 |
| Myriophyllum sibiricum | Kom. | Haloragaceae | 8 |
| Myriophyllum verticillatum | L. | Haloragaceae | 8 |
| Nabalus albus | (L.) Hook. | Asteraceae | 8 |
| Nabalus racemosus | (Michx.) Hook. | Asteraceae | 8 |
| Najas flexilis | (Willd.) Rostk. & W.L.E.Schmidt | Hydrocharitaceae | 8 |
| Najas guadalupensis | (Spreng.) Magnus | Hydrocharitaceae | 8 |
| Nassella viridula | (Trin.) Barkworth | Poaceae | 8 |
| Neottia borealis | (Morong) Szlach. | Orchidaceae | 8 |
| Neottia cordata | (L.) Rich. | Orchidaceae | 8 |
| Nothocalais cuspidata | (Pursh) Greene | Asteraceae | 8 |
| Nuphar microphylla | Fernald | Nymphaeaceae | 8 |
| Nuphar variegata | Engelm. ex Durand | Nymphaeaceae | 8 |
| Nymphaea leibergii | Morong | Nymphaeaceae | 8 |
| Nymphaea odorata | Aiton | Nymphaeaceae | 8 |
| Nymphaea tetragona | Georgi | Nymphaeaceae | 8 |
| Oenothera biennis | L. | Onagraceae | 8 |
| Oenothera cespitosa | Nutt. | Onagraceae | 8 |
| Oenothera flava | (A.Nelson) Garrett | Onagraceae | 8 |
| Oenothera nuttallii | Torr. & A.Gray | Onagraceae | 8 |
| Oenothera oakesiana | (A.Gray) J.W.Robbins ex S.Watson | Onagraceae | 8 |
| Oenothera perennis | L. | Onagraceae | 8 |
| Oenothera serrulata | Nutt. | Onagraceae | 8 |
| Oenothera suffrutescens | (Ser.) W.L.Wagner & Hoch | Onagraceae | 8 |
| Oenothera villosa | Thunb. | Onagraceae | 8 |
| Onoclea sensibilis | L. | Onocleaceae | 8 |
| Ophioglossum pusillum | Raf. | Ophioglossaceae | 8 |
| Opuntia fragilis | (Nutt.) Haw. | Cactaceae | 8 |
| Orobanche corymbosa | (Rydb.) Ferris | Orobanchaceae | 8 |
| Orobanche fasciculata | Nutt. | Orobanchaceae | 8 |
| Orobanche ludoviciana | Nutt. | Orobanchaceae | 8 |
| Orobanche uniflora | L. | Orobanchaceae | 8 |
| Orthilia secunda | (L.) House | Ericaceae | 8 |
| Orthocarpus luteus | Nutt. | Orobanchaceae | 8 |
| Oryzopsis asperifolia | Michx. | Poaceae | 8 |
| Osmorhiza claytonii | C.B.Clarke | Apiaceae | 8 |
| Osmorhiza depauperata | Phil. | Apiaceae | 8 |
| Osmorhiza longistylis | DC. | Apiaceae | 8 |
| Osmunda spectabilis | Willd. | Osmundaceae | 8 |
| Ostrya virginiana | (Mill.) K.Koch | Betulaceae | 8 |
| Oxalis stricta | L. | Oxalidaceae | 8 |
| Oxybaphus nyctagineus | (Michx.) Sweet | Nyctaginaceae | 8 |
| Oxytropis campestris | (L.) DC. | Fabaceae | 8 |
| Oxytropis lambertii | Pursh | Fabaceae | 8 |
| Oxytropis sericea | Nutt. | Fabaceae | 8 |
| Oxytropis splendens | Douglas | Fabaceae | 8 |
| Packera aurea | (L.) Á.Löve & D.Löve | Asteraceae | 8 |
| Packera cana | (Hook.) W.A.Weber & Á.Löve | Asteraceae | 8 |
| Packera indecora | (Greene) Á.Löve & D.Löve | Asteraceae | 8 |
| Packera paupercula | (Michx.) Á.Löve & D.Löve | Asteraceae | 8 |
| Panicum capillare | L. | Poaceae | 8 |
| Panicum virgatum | L. | Poaceae | 8 |
| Parietaria pensylvanica | Muhl. ex Willd. | Urticaceae | 8 |
| Parnassia glauca | Raf. | Celastraceae | 8 |
| Parnassia kotzebuei | Cham. ex Spreng. | Celastraceae | 8 |
| Parnassia palustris | L. | Celastraceae | 8 |
| Parnassia parviflora | DC. | Celastraceae | 8 |
| Parthenocissus quinquefolia | (L.) Planch. | Vitaceae | 8 |
| Pedicularis canadensis | L. | Orobanchaceae | 8 |
| Pedicularis flammea | L. | Orobanchaceae | 8 |
| Pedicularis groenlandica | Retz. | Orobanchaceae | 8 |
| Pedicularis labradorica | Wirsing | Orobanchaceae | 8 |
| Pedicularis lanceolata | Michx. | Orobanchaceae | 8 |
| Pedicularis lapponica | L. | Orobanchaceae | 8 |
| Pedicularis sudetica | Willd. | Orobanchaceae | 8 |
| Pelecyphora vivipara | (Nutt.) D.Aquino & Dan.Sánchez | Cactaceae | 8 |
| Pellaea glabella | Mett. | Pteridaceae | 8 |
| Penstemon albidus | Nutt. | Plantaginaceae | 8 |
| Penstemon gracilis | Nutt. | Plantaginaceae | 8 |
| Penstemon nitidus | Douglas ex Benth. | Plantaginaceae | 8 |
| Penstemon procerus | Douglas ex Graham | Plantaginaceae | 8 |
| Penthorum sedoides | L. | Penthoraceae | 8 |
| Persicaria amphibia | (L.) Delarbre | Polygonaceae | 8 |
| Persicaria lapathifolia | (L.) Delarbre | Polygonaceae | 8 |
| Persicaria punctata | Small | Polygonaceae | 8 |
| Persicaria sagittata | (L.) H.Gross | Polygonaceae | 8 |
| Persicaria vivipara | (L.) Ronse Decr. | Polygonaceae | 8 |
| Petasites frigidus | (L.) Fr. | Asteraceae | 8 |
| Phacelia franklinii | (R.Br.) A.Gray | Hydrophyllaceae | 8 |
| Phalaris arundinacea | L. | Poaceae | 8 |
| Phegopteris connectilis | (Michx.) Watt | Thelypteridaceae | 8 |
| Phlox hoodii | Richardson | Polemoniaceae | 8 |
| Phlox pilosa | L. | Polemoniaceae | 8 |
| Phlox subulata | L. | Polemoniaceae | 8 |
| Phragmites australis | (Cav.) Steud. | Poaceae | 8 |
| Phryma leptostachya | L. | Phrymaceae | 8 |
| Phyllodoce caerulea | (L.) Bab. | Ericaceae | 8 |
| Physalis virginiana | Mill. | Solanaceae | 8 |
| Physaria arenosa | (Richardson) O'Kane & Al-Shehbaz | Brassicaceae | 8 |
| Physostegia parviflora | Nutt. ex A.Gray | Lamiaceae | 8 |
| Physostegia virginiana | (L.) Benth. | Lamiaceae | 8 |
| Picea glauca | (Moench) Voss | Pinaceae | 8 |
| Picea mariana | Britton, Sterns & Poggenb. | Pinaceae | 8 |
| Pinguicula villosa | L. | Lentibulariaceae | 8 |
| Pinguicula vulgaris | L. | Lentibulariaceae | 8 |
| Pinus banksiana | Lamb. | Pinaceae | 8 |
| Pinus resinosa | Aiton | Pinaceae | 8 |
| Pinus strobus | L. | Pinaceae | 8 |
| Piptatheropsis micrantha | (Trin. & Rupr.) Romasch., P.M.Peterson & Soreng | Poaceae | 8 |
| Piptatheropsis pungens | (Torr. ex Spreng.) Romasch., P.M.Peterson & Soreng | Poaceae | 8 |
| Plagiobothrys scouleri | (Hook. & Arn.) I.M.Johnst. | Boraginaceae | 8 |
| Plantago elongata | Pursh | Plantaginaceae | 8 |
| Plantago maritima | L. | Plantaginaceae | 8 |
| Plantago patagonica | Jacq. | Plantaginaceae | 8 |
| Platanthera aquilonis | Sheviak | Orchidaceae | 8 |
| Platanthera dilatata | (Pursh) Lindl. ex L.C.Beck | Orchidaceae | 8 |
| Platanthera hookeri | (Torr.) Lindl. | Orchidaceae | 8 |
| Platanthera huronensis | Lindl. | Orchidaceae | 8 |
| Platanthera lacera | (Michx.) G.Don | Orchidaceae | 8 |
| Platanthera obtusata | (Banks ex Pursh) Lindl. | Orchidaceae | 8 |
| Platanthera orbiculata | (Pursh) Lindl. | Orchidaceae | 8 |
| Poa alpina | L. | Poaceae | 8 |
| Poa arctica | R.Br. | Poaceae | 8 |
| Poa cusickii | Vasey | Poaceae | 8 |
| Poa fendleriana | (Steud.) Vasey | Poaceae | 8 |
| Poa glauca | Vahl | Poaceae | 8 |
| Poa interior | Rydb. | Poaceae | 8 |
| Poa nemoralis | L. | Poaceae | 8 |
| Poa palustris | L. | Poaceae | 8 |
| Poa pratensis | L. | Poaceae | 8 |
| Poa wheeleri | Vasey | Poaceae | 8 |
| Pogonia ophioglossoides | (L.) Ker Gawl. | Orchidaceae | 8 |
| Polygala senega | L. | Polygalaceae | 8 |
| Polygonatum biflorum | (Walter) Elliott | Asparagaceae | 8 |
| Polygonum achoreum | S.F.Blake | Polygonaceae | 8 |
| Polygonum aviculare | L. | Polygonaceae | 8 |
| Polypodium sibiricum | Sipliv. | Polypodiaceae | 8 |
| Polypodium virginianum | L. | Polypodiaceae | 8 |
| Populus balsamifera | L. | Salicaceae | 8 |
| Populus deltoides | W.Bartram ex Marshall | Salicaceae | 8 |
| Populus grandidentata | Michx. | Salicaceae | 8 |
| Populus tremuloides | Michx. | Salicaceae | 8 |
| Potamogeton alpinus | Balb. | Potamogetonaceae | 8 |
| Potamogeton amplifolius | Tuck. | Potamogetonaceae | 8 |
| Potamogeton berchtoldii | Fieber | Potamogetonaceae | 8 |
| Potamogeton epihydrus | Raf. | Potamogetonaceae | 8 |
| Potamogeton foliosus | Raf. | Potamogetonaceae | 8 |
| Potamogeton friesii | Rupr. | Potamogetonaceae | 8 |
| Potamogeton gramineus | L. | Potamogetonaceae | 8 |
| Potamogeton illinoensis | Morong | Potamogetonaceae | 8 |
| Potamogeton natans | L. | Potamogetonaceae | 8 |
| Potamogeton obtusifolius | Mert. & W.D.J.Koch | Potamogetonaceae | 8 |
| Potamogeton praelongus | Wulfen | Potamogetonaceae | 8 |
| Potamogeton pusillus | L. | Potamogetonaceae | 8 |
| Potamogeton richardsonii | Rydb. | Potamogetonaceae | 8 |
| Potamogeton robbinsii | Oakes | Potamogetonaceae | 8 |
| Potamogeton spirillus | Tuck. | Potamogetonaceae | 8 |
| Potamogeton strictifolius | A.Benn. | Potamogetonaceae | 8 |
| Potamogeton zosteriformis | Fernald | Potamogetonaceae | 8 |
| Potentilla arenosa | (Turcz.) Juz. | Rosaceae | 8 |
| Potentilla bimundorum | Soják | Rosaceae | 8 |
| Potentilla concinna | Richardson | Rosaceae | 8 |
| Potentilla effusa | Douglas ex Lehm. | Rosaceae | 8 |
| Potentilla gracilis | Douglas ex Hook. | Rosaceae | 8 |
| Potentilla hippiana | Lehm. | Rosaceae | 8 |
| Potentilla litoralis | Rydb. | Rosaceae | 8 |
| Potentilla nivea | L. | Rosaceae | 8 |
| Potentilla ovina | Macoun | Rosaceae | 8 |
| Potentilla pensylvanica | L. | Rosaceae | 8 |
| Potentilla pulcherrima | Lehm. | Rosaceae | 8 |
| Potentilla rivalis | Nutt. | Rosaceae | 8 |
| Potentilla supina | L. | Rosaceae | 8 |
| Primula egaliksensis | Wormsk. | Primulaceae | 8 |
| Primula incana | M.E.Jones | Primulaceae | 8 |
| Primula meadia | (L.) A.R.Mast & Reveal | Primulaceae | 8 |
| Primula mistassinica | Michx. | Primulaceae | 8 |
| Primula pauciflora | (Greene) A.R.Mast & Reveal | Primulaceae | 8 |
| Prosartes trachycarpa | S.Watson | Liliaceae | 8 |
| Prunella vulgaris | L. | Lamiaceae | 8 |
| Prunus americana | Marshall | Rosaceae | 8 |
| Prunus nigra | Aiton | Rosaceae | 8 |
| Prunus pensylvanica | L.f. | Rosaceae | 8 |
| Prunus pumila | L. | Rosaceae | 8 |
| Prunus susquehanae | Willd. | Rosaceae | 8 |
| Prunus virginiana | L. | Rosaceae | 8 |
| Pseudognaphalium macounii | (Greene) Kartesz | Asteraceae | 8 |
| Puccinellia nuttalliana | (Schult.) Hitchc. | Poaceae | 8 |
| Pulsatilla nuttalliana | (DC.) Spreng. | Ranunculaceae | 8 |
| Pyrola americana | Sweet | Ericaceae | 8 |
| Pyrola asarifolia | Michx. | Ericaceae | 8 |
| Pyrola chlorantha | Sw. | Ericaceae | 8 |
| Pyrola elliptica | Nutt. | Ericaceae | 8 |
| Pyrola grandiflora | Radius | Ericaceae | 8 |
| Pyrola minor | L. | Ericaceae | 8 |
| Quercus macrocarpa | Michx. | Fagaceae | 8 |
| Ranunculus abortivus | L. | Ranunculaceae | 8 |
| Ranunculus fascicularis | Muhl. ex Bigelow | Ranunculaceae | 8 |
| Ranunculus flabellaris | Raf. | Ranunculaceae | 8 |
| Ranunculus flammula | L. | Ranunculaceae | 8 |
| Ranunculus gmelinii | DC. | Ranunculaceae | 8 |
| Ranunculus hispidus | Michx. | Ranunculaceae | 8 |
| Ranunculus hyperboreus | Rottb. | Ranunculaceae | 8 |
| Ranunculus lapponicus | L. | Ranunculaceae | 8 |
| Ranunculus macounii | Britton | Ranunculaceae | 8 |
| Ranunculus minimus | E.H.L.Krause | Ranunculaceae | 8 |
| Ranunculus pensylvanicus | L.f. | Ranunculaceae | 8 |
| Ranunculus rhomboideus | Goldie | Ranunculaceae | 8 |
| Ranunculus sceleratus | L. | Ranunculaceae | 8 |
| Ranunculus trichophyllus | Chaix | Ranunculaceae | 8 |
| Ratibida columnifera | (Nutt.) Wooton & Standl. | Asteraceae | 8 |
| Rhamnus alnifolia | L'Hér. | Rhamnaceae | 8 |
| Rhinanthus groenlandicus | Chabert | Orobanchaceae | 8 |
| Rhododendron groenlandicum | (Oeder) Kron & Judd | Ericaceae | 8 |
| Rhododendron lapponicum | (L.) Wahlenb. | Ericaceae | 8 |
| Rhododendron tomentosum | Harmaja | Ericaceae | 8 |
| Rhus glabra | L. | Anacardiaceae | 8 |
| Rhynchospora alba | (L.) Vahl | Cyperaceae | 8 |
| Rhynchospora capillacea | Torr. | Cyperaceae | 8 |
| Ribes americanum | Mill. | Grossulariaceae | 8 |
| Ribes glandulosum | Weber | Grossulariaceae | 8 |
| Ribes hirtellum | Michx. | Grossulariaceae | 8 |
| Ribes hudsonianum | Richardson | Grossulariaceae | 8 |
| Ribes lacustre | (Pers.) Poir. | Grossulariaceae | 8 |
| Ribes oxyacanthoides | L. | Grossulariaceae | 8 |
| Ribes triste | Pall. | Grossulariaceae | 8 |
| Rorippa palustris | (L.) Besser | Brassicaceae | 8 |
| Rosa acicularis | Lindl. | Rosaceae | 8 |
| Rosa arkansana | Porter | Rosaceae | 8 |
| Rosa blanda | Aiton | Rosaceae | 8 |
| Rosa woodsii | Lindl. | Rosaceae | 8 |
| Rubus chamaemorus | L. | Rosaceae | 8 |
| Rubus idaeus | L. | Rosaceae | 8 |
| Rubus pubescens | Raf. | Rosaceae | 8 |
| Rudbeckia hirta | L. | Asteraceae | 8 |
| Rudbeckia laciniata | L. | Asteraceae | 8 |
| Rumex britannica | L. | Polygonaceae | 8 |
| Rumex maritimus | L. | Polygonaceae | 8 |
| Rumex occidentalis | S.Watson | Polygonaceae | 8 |
| Rumex triangulivalvis | (Danser) Rech.f. | Polygonaceae | 8 |
| Rumex venosus | Pursh | Polygonaceae | 8 |
| Ruppia cirrhosa | (Petagna) Grande | Ruppiaceae | 8 |
| Sabulina dawsonensis | (Britton) Rydb. | Caryophyllaceae | 8 |
| Sabulina rubella | (Wahlenb.) Dillenb. & Kadereit | Caryophyllaceae | 8 |
| Sagina nodosa | (L.) Fenzl | Caryophyllaceae | 8 |
| Sagittaria cuneata | E.Sheld. | Alismataceae | 8 |
| Sagittaria latifolia | Willd. | Alismataceae | 8 |
| Sagittaria rigida | Pursh | Alismataceae | 8 |
| Salicornia rubra | A.Nelson | Chenopodiaceae | 8 |
| Salix alaxensis | (Andersson) Coville | Salicaceae | 8 |
| Salix amygdaloides | Andersson | Salicaceae | 8 |
| Salix arctophila | Cockerell ex A.Heller | Salicaceae | 8 |
| Salix bebbiana | Sarg. | Salicaceae | 8 |
| Salix brachycarpa | Nutt. | Salicaceae | 8 |
| Salix candida | Flüggé ex Willd. | Salicaceae | 8 |
| Salix discolor | Muhl. | Salicaceae | 8 |
| Salix glauca | L. | Salicaceae | 8 |
| Salix herbacea | L. | Salicaceae | 8 |
| Salix humilis | Marshall | Salicaceae | 8 |
| Salix interior | Rowlee | Salicaceae | 8 |
| Salix lasiandra | Benth. | Salicaceae | 8 |
| Salix lucida | Muhl. | Salicaceae | 8 |
| Salix myrtillifolia | Andersson | Salicaceae | 8 |
| Salix pedicellaris | Pursh | Salicaceae | 8 |
| Salix pellita | (Andersson) Bebb | Salicaceae | 8 |
| Salix petiolaris | Sm. | Salicaceae | 8 |
| Salix planifolia | Pursh | Salicaceae | 8 |
| Salix pseudomonticola | C.R.Ball | Salicaceae | 8 |
| Salix pyrifolia | Andersson | Salicaceae | 8 |
| Salix reticulata | L. | Salicaceae | 8 |
| Salix scouleriana | Barratt | Salicaceae | 8 |
| Salix serissima | (L.H.Bailey ex Arthur) Fernald | Salicaceae | 8 |
| Salix vestita | Pursh | Salicaceae | 8 |
| Sambucus canadensis | L. | Viburnaceae | 8 |
| Sambucus racemosa | L. | Viburnaceae | 8 |
| Sanguinaria canadensis | L. | Papaveraceae | 8 |
| Sanicula marilandica | L. | Apiaceae | 8 |
| Sarracenia purpurea | L. | Sarraceniaceae | 8 |
| Saxifraga aizoides | L. | Saxifragaceae | 8 |
| Saxifraga cernua | L. | Saxifragaceae | 8 |
| Saxifraga cespitosa | L. | Saxifragaceae | 8 |
| Saxifraga hirculus | L. | Saxifragaceae | 8 |
| Saxifraga hyperborea | R.Br. | Saxifragaceae | 8 |
| Saxifraga oppositifolia | L. | Saxifragaceae | 8 |
| Saxifraga paniculata | Mill. | Saxifragaceae | 8 |
| Saxifraga tricuspidata | Rottb. | Saxifragaceae | 8 |
| Sceptridium multifidum | (S.G.Gmel.) M.Nishida | Ophioglossaceae | 8 |
| Scheuchzeria palustris | L. | Scheuchzeriaceae | 8 |
| Schizachne purpurascens | (Torr.) Swallen | Poaceae | 8 |
| Schizachyrium scoparium | (Michx.) Nash | Poaceae | 8 |
| Schoenoplectus acutus | (Muhl. ex Bigelow) Á.Löve & D.Löve | Cyperaceae | 8 |
| Schoenoplectus heterochaetus | (Chase) Soják | Cyperaceae | 8 |
| Schoenoplectus pungens | (Vahl) Palla | Cyperaceae | 8 |
| Schoenoplectus tabernaemontani | (C.C.Gmel.) Palla | Cyperaceae | 8 |
| Schoenoplectus torreyi | (Olney) Palla | Cyperaceae | 8 |
| Scirpus atrocinctus | Fernald | Cyperaceae | 8 |
| Scirpus atrovirens | Willd. | Cyperaceae | 8 |
| Scirpus cyperinus | (L.) Kunth | Cyperaceae | 8 |
| Scirpus microcarpus | J.Presl & C.Presl | Cyperaceae | 8 |
| Scutellaria galericulata | L. | Lamiaceae | 8 |
| Scutellaria lateriflora | L. | Lamiaceae | 8 |
| Scutellaria parvula | Michx. | Lamiaceae | 8 |
| Selaginella longipila | Hieron. | Selaginellaceae | 8 |
| Selaginella rupestris | (L.) Spring | Selaginellaceae | 8 |
| Selaginella spinulosa | A.Braun ex Döll | Selaginellaceae | 8 |
| Senecio eremophilus | Richardson | Asteraceae | 8 |
| Senecio integerrimus | Nutt. | Asteraceae | 8 |
| Shepherdia argentea | (Pursh) Nutt. | Elaeagnaceae | 8 |
| Shepherdia canadensis | (L.) Nutt. | Elaeagnaceae | 8 |
| Silene antirrhina | L. | Caryophyllaceae | 8 |
| Silene drummondii | Hook. | Caryophyllaceae | 8 |
| Silene involucrata | (Cham. & Schltdl.) Bocquet | Caryophyllaceae | 8 |
| Silene menziesii | Hook. | Caryophyllaceae | 8 |
| Silene uralensis | (Rupr.) Bocquet | Caryophyllaceae | 8 |
| Sisyrinchium campestre | E.P.Bicknell | Iridaceae | 8 |
| Sisyrinchium montanum | Greene | Iridaceae | 8 |
| Sisyrinchium mucronatum | Michx. | Iridaceae | 8 |
| Sium suave | Walter | Apiaceae | 8 |
| Solanum emulans | Raf. | Solanaceae | 8 |
| Solanum triflorum | Nutt. | Solanaceae | 8 |
| Solidago altissima | L. | Asteraceae | 8 |
| Solidago canadensis | L. | Asteraceae | 8 |
| Solidago elongata | Nutt. | Asteraceae | 8 |
| Solidago gigantea | Aiton | Asteraceae | 8 |
| Solidago hispida | Muhl. ex Willd. | Asteraceae | 8 |
| Solidago juncea | Aiton | Asteraceae | 8 |
| Solidago lepida | DC. | Asteraceae | 8 |
| Solidago missouriensis | Nutt. | Asteraceae | 8 |
| Solidago multiradiata | Aiton | Asteraceae | 8 |
| Solidago nemoralis | Aiton | Asteraceae | 8 |
| Solidago ptarmicoides | (Torr. & A.Gray) B.Boivin | Asteraceae | 8 |
| Solidago riddellii | Frank | Asteraceae | 8 |
| Solidago rigida | L. | Asteraceae | 8 |
| Solidago simplex | Kunth | Asteraceae | 8 |
| Solidago uliginosa | Nutt. | Asteraceae | 8 |
| Sorbus decora | (Sarg.) C.K.Schneid. | Rosaceae | 8 |
| Sorghastrum nutans | (L.) Nash | Poaceae | 8 |
| Sparganium americanum | Nutt. | Typhaceae | 8 |
| Sparganium angustifolium | Michx. | Typhaceae | 8 |
| Sparganium emersum | Rehmann | Typhaceae | 8 |
| Sparganium eurycarpum | Engelm. | Typhaceae | 8 |
| Sparganium fluctuans | (Engelm.) B.L.Rob. | Typhaceae | 8 |
| Sparganium natans | L. | Typhaceae | 8 |
| Spergularia marina | (L.) Besser | Caryophyllaceae | 8 |
| Sphaeralcea coccinea | (Nutt.) Rydb. | Malvaceae | 8 |
| Sphenopholis intermedia | (Rydb.) Rydb. | Poaceae | 8 |
| Sphenopholis obtusata | (Michx.) Scribn. | Poaceae | 8 |
| Spinulum annotinum | (L.) A.Haines | Lycopodiaceae | 8 |
| Spiraea alba | Du Roi | Rosaceae | 8 |
| Spiranthes lacera | (Raf.) Raf. | Orchidaceae | 8 |
| Spiranthes magnicamporum | Sheviak | Orchidaceae | 8 |
| Spiranthes romanzoffiana | Cham. | Orchidaceae | 8 |
| Spirodela polyrhiza | (L.) Schleid. | Araceae | 8 |
| Sporobolus compositus | (Poir.) Merr. | Poaceae | 8 |
| Sporobolus cryptandrus | (Torr.) A.Gray | Poaceae | 8 |
| Sporobolus heterolepis | (A.Gray) A.Gray | Poaceae | 8 |
| Sporobolus hookerianus | P.M.Peterson & Saarela | Poaceae | 8 |
| Sporobolus michauxianus | (Hitchc.) P.M.Peterson & Saarela | Poaceae | 8 |
| Sporobolus neglectus | Nash | Poaceae | 8 |
| Sporobolus rigidus | (Buckley) P.M.Peterson | Poaceae | 8 |
| Stachys hispida | Pursh | Lamiaceae | 8 |
| Stachys pilosa | Nutt. | Lamiaceae | 8 |
| Stellaria borealis | Bigelow | Caryophyllaceae | 8 |
| Stellaria crassifolia | Ehrh. | Caryophyllaceae | 8 |
| Stellaria humifusa | Rottb. | Caryophyllaceae | 8 |
| Stellaria longifolia | Muhl. ex Willd. | Caryophyllaceae | 8 |
| Stellaria longipes | Goldie | Caryophyllaceae | 8 |
| Streptopus amplexifolius | (L.) DC. | Liliaceae | 8 |
| Streptopus lanceolatus | (Aiton) Reveal | Liliaceae | 8 |
| Stuckenia filiformis | (Pers.) Börner | Potamogetonaceae | 8 |
| Stuckenia pectinata | (L.) Börner | Potamogetonaceae | 8 |
| Suaeda calceoliformis | (Hook.) Moq. | Chenopodiaceae | 8 |
| Suaeda maritima | (L.) Dumort. | Chenopodiaceae | 8 |
| Subularia aquatica | L. | Brassicaceae | 8 |
| Symphoricarpos albus | (L.) S.F.Blake | Caprifoliaceae | 8 |
| Symphoricarpos occidentalis | (R.Br.) Hook. | Caprifoliaceae | 8 |
| Symphyotrichum boreale | (Torr. & A.Gray) Á.Löve & D.Löve | Asteraceae | 8 |
| Symphyotrichum ciliatum | (Ledeb.) G.L.Nesom | Asteraceae | 8 |
| Symphyotrichum cordifolium | (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 robynsianum | (J.Rousseau) Brouillet & Labrecque | Asteraceae | 8 |
| Symphyotrichum sericeum | (Vent.) G.L.Nesom | Asteraceae | 8 |
| Tanacetum bipinnatum | Sch.Bip. | Asteraceae | 8 |
| Taxus canadensis | Marshall | Taxaceae | 8 |
| Tephroseris palustris | Fourr. | Asteraceae | 8 |
| Teucrium canadense | L. | Lamiaceae | 8 |
| Thacla natans | (Pall.) Deyl & Soják | Ranunculaceae | 8 |
| Thalictrum dasycarpum | Fisch., C.A.Mey. & Avé-Lall. | Ranunculaceae | 8 |
| Thalictrum revolutum | DC. | Ranunculaceae | 8 |
| Thalictrum sparsiflorum | Turcz. ex Fisch. & C.A.Mey. | Ranunculaceae | 8 |
| Thalictrum venulosum | Trel. | Ranunculaceae | 8 |
| Thelypteris palustris | Schott | Thelypteridaceae | 8 |
| Thermopsis rhombifolia | (Pursh) Richardson | Fabaceae | 8 |
| Thuja occidentalis | L. | Cupressaceae | 8 |
| Tilia americana | L. | Malvaceae | 8 |
| Tofieldia pusilla | (Michx.) Pers. | Tofieldiaceae | 8 |
| Tomostima reptans | (Lam.) Al-Shehbaz, M.Koch & Jordon-Thaden | Brassicaceae | 8 |
| Townsendia exscapa | (Richardson) Porter | Asteraceae | 8 |
| Toxicodendron radicans | (L.) Kuntze | Anacardiaceae | 8 |
| Tradescantia occidentalis | (Britton) Smyth | Commelinaceae | 8 |
| Triantha glutinosa | (Michx.) Baker | Tofieldiaceae | 8 |
| Trichophorum alpinum | (L.) Pers. | Cyperaceae | 8 |
| Trichophorum cespitosum | (L.) Hartm. | Cyperaceae | 8 |
| Triglochin maritima | L. | Juncaginaceae | 8 |
| Triglochin palustris | L. | Juncaginaceae | 8 |
| Trillium cernuum | L. | Melanthiaceae | 8 |
| Tripleurospermum hookeri | Sch.Bip. | Asteraceae | 8 |
| Turritis glabra | L. | Brassicaceae | 8 |
| Typha angustifolia | L. | Typhaceae | 8 |
| Typha latifolia | L. | Typhaceae | 8 |
| Ulmus americana | L. | Ulmaceae | 8 |
| Urtica gracilis | Aiton | Urticaceae | 8 |
| Utricularia cornuta | Michx. | Lentibulariaceae | 8 |
| Utricularia gibba | L. | Lentibulariaceae | 8 |
| Utricularia intermedia | Hayne | Lentibulariaceae | 8 |
| Utricularia macrorhiza | Leconte | Lentibulariaceae | 8 |
| Utricularia minor | L. | Lentibulariaceae | 8 |
| Uvularia grandiflora | Sm. | Colchicaceae | 8 |
| Uvularia sessilifolia | L. | Colchicaceae | 8 |
| Vaccinium angustifolium | Aiton | Ericaceae | 8 |
| Vaccinium cespitosum | Michx. | Ericaceae | 8 |
| Vaccinium myrtilloides | Michx. | Ericaceae | 8 |
| Vaccinium oxycoccos | L. | Ericaceae | 8 |
| Vaccinium uliginosum | L. | Ericaceae | 8 |
| Vaccinium vitis-idaea | L. | Ericaceae | 8 |
| Vahlodea atropurpurea | (Wahlenb.) Fr. | Poaceae | 8 |
| Valeriana dioica | L. | Caprifoliaceae | 8 |
| Vallisneria americana | Michx. | Hydrocharitaceae | 8 |
| Verbena bracteata | Cav. ex Lag. & Rodr. | Verbenaceae | 8 |
| Verbena hastata | L. | Verbenaceae | 8 |
| Verbena urticifolia | L. | Verbenaceae | 8 |
| Vernonia fasciculata | Michx. | Asteraceae | 8 |
| Veronica americana | (Raf.) Schwein. ex Benth. | Plantaginaceae | 8 |
| Veronica catenata | Pennell | Plantaginaceae | 8 |
| Veronica peregrina | L. | Plantaginaceae | 8 |
| Veronica scutellata | L. | Plantaginaceae | 8 |
| Veronicastrum virginicum | (L.) Farw. | Plantaginaceae | 8 |
| Viburnum edule | (Michx.) Raf. | Viburnaceae | 8 |
| Viburnum lentago | L. | Viburnaceae | 8 |
| Viburnum opulus | L. | Viburnaceae | 8 |
| Viburnum rafinesqueanum | Schult. | Viburnaceae | 8 |
| Vicia americana | Muhl. ex Willd. | Fabaceae | 8 |
| Viola adunca | Sm. | Violaceae | 8 |
| Viola blanda | Willd. | Violaceae | 8 |
| Viola canadensis | L. | Violaceae | 8 |
| Viola labradorica | Schrank | Violaceae | 8 |
| Viola macloskeyi | F.E.Lloyd | Violaceae | 8 |
| Viola nephrophylla | Greene | Violaceae | 8 |
| Viola nuttallii | Pursh | Violaceae | 8 |
| Viola palustris | L. | Violaceae | 8 |
| Viola pedatifida | G.Don | Violaceae | 8 |
| Viola pubescens | Aiton | Violaceae | 8 |
| Viola renifolia | A.Gray | Violaceae | 8 |
| Viola selkirkii | Pursh ex Goldie | Violaceae | 8 |
| Viola sororia | Willd. | Violaceae | 8 |
| Vitis riparia | Michx. | Vitaceae | 8 |
| Wolffia columbiana | H.Karst. | Araceae | 8 |
| Woodsia alpina | (Bolton) Gray | Woodsiaceae | 8 |
| Woodsia glabella | R.Br. | Woodsiaceae | 8 |
| Woodsia ilvensis | (L.) R.Br. | Woodsiaceae | 8 |
| Woodsia oregana | D.C.Eaton | Woodsiaceae | 8 |
| Woodsia scopulina | D.C.Eaton | Woodsiaceae | 8 |
| Xanthisma spinulosum | (Pursh) D.R.Morgan & R.L.Hartm. | Asteraceae | 8 |
| Xanthium orientale | L. | Asteraceae | 8 |
| Zannichellia palustris | L. | Potamogetonaceae | 8 |
| Zizania aquatica | L. | Poaceae | 8 |
| Zizania palustris | L. | Poaceae | 8 |
| Zizia aptera | (A.Gray) Fernald | Apiaceae | 8 |
| Arctanthemum arcticum | (L.) Tzvelev | Asteraceae | 7 |
| Botrychium pallidum | W.H.Wagner | Ophioglossaceae | 7 |
| Carex backii | Boott | Cyperaceae | 7 |
| Carex merritt-fernaldii | Mack. | Cyperaceae | 7 |
| Corispermum americanum | (Nutt.) Nutt. | Chenopodiaceae | 7 |
| Crepis runcinata | (E.James) Torr. & A.Gray | Asteraceae | 7 |
| Festuca saximontana | Rydb. | Poaceae | 7 |
| Isoetes lacustris | L. | Isoetaceae | 7 |
| Koenigia islandica | L. | Polygonaceae | 7 |
| Neottia auriculata | (Wiegand) Szlach. | Orchidaceae | 7 |
| Oxytropis arctica | R.Br. | Fabaceae | 7 |
| Plantago eriopoda | Torr. | Plantaginaceae | 7 |
| Scirpus pallidus | (Britton) Fernald | Cyperaceae | 7 |
| Calystegia macounii | (Greene) Brummitt | Convolvulaceae | 6 |
| Carex conoidea | Willd. | Cyperaceae | 6 |
| Draba incana | L. | Brassicaceae | 6 |
| Juncus triglumis | L. | Juncaceae | 6 |
| Platanthera praeclara | Sheviak & M.L.Bowles | Orchidaceae | 6 |
| Polygonum ramosissimum | Michx. | Polygonaceae | 6 |
| Scolochloa festucacea | (Willd.) Link | Poaceae | 6 |
| Asclepias lanuginosa | Nutt. | Apocynaceae | 5 |
| Blysmus rufus | (Huds.) Link | Cyperaceae | 5 |
| Carex adelostoma | V.I.Krecz. | Cyperaceae | 5 |
| Carex loliacea | L. | Cyperaceae | 5 |
| Carex oederi | Retz. | Cyperaceae | 5 |
| Chrysosplenium iowense | Rydb. | Saxifragaceae | 5 |
| Euphrasia hudsoniana | Fernald & Wiegand | Orobanchaceae | 5 |
| Hippuris lanceolata | Retz. | Plantaginaceae | 5 |
| Juncus vaseyi | Engelm. | Juncaceae | 5 |
| Muhlenbergia andina | (Nutt.) Hitchc. | Poaceae | 5 |
| Puccinellia phryganodes | (Trin.) Scribn. & Merr. | Poaceae | 5 |
| Agrostis mertensii | Trin. | Poaceae | 4 |
| Carex laeviconica | Dewey | Cyperaceae | 4 |
| Carex torreyi | Tuck. | Cyperaceae | 4 |
| Draba nivalis | Lilj. | Brassicaceae | 4 |
| Glyceria pulchella | (Nash) K.Schum. | Poaceae | 4 |
| Lepidium ramosissimum | A.Nelson | Brassicaceae | 4 |
| Pedicularis parviflora | Sm. | Orobanchaceae | 4 |
| Physostegia ledinghamii | (B.Boivin) P.D.Cantino | Lamiaceae | 4 |
| Potamogeton oakesianus | J.W.Robbins | Potamogetonaceae | 4 |
| Salix arbusculoides | Andersson | Salicaceae | 4 |
| Salix calcicola | Fernald & Wiegand | Salicaceae | 4 |
| Solidago mollis | Bartl. | Asteraceae | 4 |
| Arabidopsis arenicola | (Richardson) Al-Shehbaz, Elven, D.F.Murray & Warwick | Brassicaceae | 3 |
| Carex echinodes | (Fernald) P.Rothr., Reznicek & Hipp | Cyperaceae | 3 |
| Carex membranacea | Hook. | Cyperaceae | 3 |
| Carex parryana | Dewey | Cyperaceae | 3 |
| Carex subspathacea | Wormsk. ex Hornem. | Cyperaceae | 3 |
| Chenopodium desiccatum | A.Nelson | Chenopodiaceae | 3 |
| Erysimum inconspicuum | (S.Watson) MacMill. | Brassicaceae | 3 |
| Festuca richardsonii | Hook. | Poaceae | 3 |
| Gentianella amarella | (L.) Börner | Gentianaceae | 3 |
| Hippuris tetraphylla | L.f. | Plantaginaceae | 3 |
| Poa alpigena | Lindm. | Poaceae | 3 |
| Pteridium latiusculum | Hieron. | Dennstaedtiaceae | 3 |