Pennsylvania Protected Plants
A total of 539 species of plants are now listed as extirpated, endangered, threatened, rare or vulnerable. Source: Thompson, S.A. 1997. Vascular plants: review of status in Pennsylvania (20 October 2002). Department of Conservation and Natural Resources.
| USDA Symbol | Scientific Name | Common Name | PA Protected Status |
|---|---|---|---|
| ACDE4 | Acalypha deamii (Weath.) H.E. Ahles | two-seeded copperleaf | Extirpated |
| ACRE | Aconitum reclinatum A. Gray | white monkshood | Endangered |
| ACUN | Aconitum uncinatum L. | blue monkshood | Threatened |
| ACAM | Acorus americanus (Raf.) Raf. | sweet flag | Endangered |
| ACPO11 (CIAM) | Actaea podocarpa DC. (Cimicifuga americana Michx.) | mountain bugbane | Rare |
| AEVI3 | Aeschynomene virginica (L.) Britton, Sterns & Poggenb. | sensitive joint-vetch | Extirpated |
| AGAU3 (TOAU) | Agalinis auriculata (Michx.) S.F. Blake (Tomanthera auriculata (Michx.) Raf.) | eared false-foxglove | Endangered |
| AGOB (AGDE5) | Agalinis obtusifolia Raf.(Agalinis decemloba (Greene)) Pennell | blue-ridge false-foxglove | Extirpated |
| AGPA12 | Agalinis paupercula (A. Gray) Britton | small-flowered false foxglove | Endangered |
| AGPE (AGAL8) | Agrostis perennans (Walter) Tuck. (Agrostis altissima (Walter) Tuck.) | tall bentgrass | Extirpated |
| ALFA2 | Aletris farinosa L. | colic-root | Endangered |
| ALTR7 (ALPLA) | Alisma triviale Pursh (Alisma plantago-aquatica L. var. americanum Schult.) | broad-leaved water plantain | Endangered |
| ALVIC | Alnus viridis (Chaix) DC. ssp. crispa (Aiton) Turrill | mountain alder | Endangered |
| AMCA2 | Amaranthus cannabinus (L.) Sauer | waterhemp ragweed | Rare |
| AMBA | Amelanchier bartramiana (Tausch) M. Roem. | oblong-fruited serviceberry | Endangered |
| AMHU2 | Amelanchier humilis Wiegand | low serviceberry | Endangered |
| AMOB2 | Amelanchier obovalis (Michx.) Ashe | Coastal Plain serviceberry | Endangered |
| AMSA | Amelanchier sanguinea (Pursh) DC. | roundleaf serviceberry | Endangered |
| AMCO | Ammannia coccinea Rottb. | scarlet ammannia | Threatened |
| AMBR | Ammophila breviligulata Fernald | America beachgrass | Threatened |
| ANPO | Andromeda polifolia L. | bog-rosemary | Rare |
| ANCY | Anemone cylindrica A. Gray | long-fruited anemone | Endangered |
| ANSO | Antennaria solitaria Rydb. | single-head pussytoes | Endangered |
| ANVI13 | Antennaria virginica Stebbins | shale-barren pussytoes | Rare |
| APHY | Aplectrum hyemale (Muhl. ex Willd.) Torr. | puttyroot | Rare |
| ARHI | Arabis hirsuta (L.) Scop. | hairy rock-cress | Endangered |
| ARMI5 | Arabis missouriensis Greene | Missouri rock-cress | Endangered |
| ARPU3 | Arceuthobium pusillum Peck | dwarf mistletoe | Threatened |
| ARUV | Arctostaphylos uva-ursi (L.) Spreng. | bearberry manzanita | Extirpated |
| ARBU | Arethusa bulbosa L. | swamp-pink | Endangered |
| ARAN7 (POAN5) | Argentina anserina (L.) Rydb. (Potentilla anserina L.) | silverweed | Threatened |
| ARPU8 | Aristida purpurascens Poir. | arrow feather | Threatened |
| ARAC3 | Arnica acaulis (Walter) Britton, Sterns & Poggenb. | leopard's-bane | Endangered |
| ARCAC | Artemisia campestris L. ssp. caudata (Michx.) H.M. Hall & Clem. | beach wormwood | Endangered |
| ASRU | Asclepias rubra L. | red milkweed | Extirpated |
| ASVA | Asclepias variegata L. | white milkweed | Endangered |
| ASBR2 | Asplenium bradleyi D.C. Eaton | Bradley's spleenwort | Endangered |
| ASPI | Asplenium pinnatifidum Nutt. | lobed spleenwort | Rare |
| ASRE | Asplenium resiliens Kunze | black-stalked spleenwort | Endangered |
| ASNE2 | Astragalus neglectus (Torr. & A. Gray) Sheldon | Cooper's milk-vetch | Endangered |
| BAHA | Baccharis halimifolia L. | eastern baccharis | Rare |
| BECA2 | Berberis canadensis Mill. | American barberry | Extirpated |
| BIBE2 (MEBE2) | Bidens beckii Torr. ex Spreng. (Megalodonta beckii (Torr. ex Spreng.) Greene) | Beck's water-marigold | Endangered |
| BIBI3 | Bidens bidentoides (Nutt.) Britton | swamp beggar-ticks | Endangered |
| BOAS | Boltonia asteroides (L.) L'Hér. | aster-like boltonia | Endangered |
| BOCU | Bouteloua curtipendula (Michx.) Torr. | tall gramma | Threatened |
| BUAM | Buchnera americana L. | bluehearts | Extirpated |
| CAED | Cakile edentula (Bigelow) Hook. | American sea-rocket | Rare |
| CASC5 | Camassia scilloides (Raf.) Cory | wild hyacinth | Endangered |
| CAAD2 | Carex adusta Boott | crowded sedge | Extirpated |
| CAAL3 | Carex alata Torr. | broadwinged sedge | Threatened |
| CAAQ | Carex aquatilis Wahlenb. | water sedge | Threatened |
| CAAT2 | Carex atherodes Spreng. | awned sedge | Endangered |
| CAAU3 | Carex aurea Nutt. | golden-fruited sedge | Endangered |
| CABA3 | Carex backii Boott | Rocky Mountain sedge | Extirpated |
| CABA9 | Carex barrattii Schwein. & Torr. | Barratt's sedge | Extirpated |
| CABE2 | Carex bebbii Olney ex Fernald | Bebb's sedge | Endangered |
| CABI3 | Carex bicknellii Britton | Bicknell's sedge | Endangered |
| CABU7 | Carex bullata Schkuhr ex Willd. | bull sedge | Endangered |
| CABU6 | Carex buxbaumii Wahlenb. | brown sedge | Rare |
| CACA14 | Carex careyana Torr. ex Dewey | Carey's sedge | Endangered |
| CACH5 | Carex chordorrhiza Ehrh. ex L. f. | creeping sedge | Extirpated |
| CACO21 | Carex collinsii Nutt. | Collin's sedge | Threatened |
| CACR4 | Carex crawfordii Fernald | Crawford's sedge | Endangered |
| CACRB | Carex crinita Lam. var. brevicrinis Fernald | short hair sedge | Endangered |
| CACR9 | Carex cryptolepis Mack. | northeastern sedge | Endangered |
| CADI4 | Carex diandra Schrank | lesser pinacled sedge | Threatened |
| CADI6 | Carex disperma Dewey | soft-leaved sedge | Rare |
| CAEB2 | Carex eburnea Boott | ebony sedge | Endangered |
| CAFL4 | Carex flava L. | yellow sedge | Threatened |
| CAFO4 | Carex formosa Dewey | handsome sedge | Endangered |
| CAGA3 | Carex garberi Fernald | elk sedge | Endangered |
| CAGE2 | Carex geyeri Boott | Geyer's sedge | Endangered |
| CAHY3 | Carex hyalinolepis Steud. | shore-line sedge | Extirpated |
| CALA11 | Carex lasiocarpa Ehrh. | slender sedge | Rare |
| CALI7 | Carex limosa L. | mud sedge | Threatened |
| CAMAI2 (CAPA22) | Carex magellanica Lam. ssp. irrigua (Wahlenb.) Hultén (Carex paupercula Michx.) | bog sedge | Rare |
| CAME2 | Carex meadii Dewey | Mead's sedge | Endangered |
| CAMI18 | Carex mitchelliana M.A. Curtis | Mitchell's sedge | Endangered |
| CAOL3 | Carex oligosperma Michx. | few seeded sedge | Threatened |
| CAPA19 | Carex pauciflora Lightf. | few-flowered sedge | Endangered |
| CAPO4 | Carex polymorpha Muhl. | variable sedge | Threatened |
| CAPR6 | Carex prairea Dewey ex Alph. Wood | prairie sedge | Threatened |
| CAPS | Carex pseudocyperus L. | cyperus-like sedge | Endangered |
| CARE4 | Carex retrorsa Schwein. | backward sedge | Endangered |
| CARI | Carex richardsonii R. Br. | Richardson's sedge | Endangered |
| CASA8 | Carex sartwellii Dewey | Sartwell's sedge | Extirpated |
| CASC9 | Carex schweinitzii Dewey ex Schwein. | Schweinitz's sedge | Endangered |
| CASI12 (CAAE) | Carex siccata Dewey (Carex aenea Fernald) | Fernald's hay sedge | Extirpated |
| CAST16 | Carex sterilis Willd. | Atlantic sedge | Endangered |
| CATE6 | Carex tetanica Schkuhr | Wood's sedge | Threatened |
| CATY | Carex typhina Michx. | cattail sedge | Endangered |
| CAVI5 | Carex viridula Michx. | green sedge | Endangered |
| CAWI7 | Carex wiegandii Mack. | Wiegand's sedge | Threatened |
| CEARV4 (CEARV6) | Cerastium arvense L. ssp. velutinum (Raf.) Ugborogho var. villosum (Muhl. ex Darl.) Hollick & Britton (Cerastium arvense L. var. villosissimum Pennell) | mouse-ear chickweed | Endangered |
| CHTH2 | Chamaecyparis thyoides (L.) Britton, Sterns & Poggenb. | Atlantic white cedar | Extirpated |
| CHPO6 | Chamaesyce polygonifolia (L.) Small | small sea-side spurge | Threatened |
| CHLA6 | Chasmanthium laxum (L.) Yates | slender sea-oats | Endangered |
| CHFO3 | Chenopodium foggii Wahl | Fogg's goosefoot | Endangered |
| CHVI5 | Chrysogonum virginianum L. | green-and-gold | Endangered |
| CHMA14 | Chrysopsis mariana (L.) Elliot | Maryland golden aster | Endangered |
| CIHO2 | Cirsium horridulum Michx. | horrible thistle | Endangered |
| CLMA | Cladium mariscoides (Muhl.) Torr. | twig rush | Endangered |
| CLVI4 | Clematis viorna L. | vase-vine leather-flower | Endangered |
| CLAC3 | Clethra acuminata Michx. | mountain pepper-bush | Endangered |
| CLMA4 | Clitoria mariana L. | butterfly-pea | Endangered |
| COER | Commelina erecta L. | slender day-flower | Extirpated |
| COVI3 | Commelina virginica L. | Virginia day-flower | Extirpated |
| COCH2 | Conioselinum chinense (L.) Britton, Sterns & Poggenb. | hemlock-parsley | Endangered |
| COWI5 (COWI2) | Corallorhiza wisteriana Conrad (Corallorrhiza wisteriana Conrad, orth. var.) | Wister's coral-root | Endangered |
| CORO | Coreopsis rosea Nutt. | pink tickseed | Extirpated |
| COAU2 | Corydalis aurea Willd. | golden corydalis | Endangered |
| CRAQ | Crassula aquatica (L.) Schoenl. | water pigmy-weed | Extirpated |
| CRWI5 (CREL2) | Croton willdenowii G.L. Webster (Crotonopsis elliptica Willd.) | elliptical rushfoil | Extirpated |
| CRST2 | Cryptogramma stelleri (S.G. Gmel.) Prantl | slender rock-brake | Endangered |
| CYFR4 (CYFR) | Cymophyllus fraserianus (Ker Gawl.) Kartesz & Gandhi (Cymophyllus fraseri (Andrews) Mack. ex Britton) | Fraser's sedge | Endangered |
| CYLA | Cynanchum laeve (Michx.) Pers. | smooth swallow-wort | Endangered |
| CYVIB (CYBO) | Cynoglossum virginianum L. var. boreale (Fernald) Cooperr. (Cynoglossum boreale Fernald) | northern hound's-tongue | Extirpated |
| CYDI3 | Cyperus diandrus Torr. | umbrella flatsedge | Endangered |
| CYHO | Cyperus houghtonii Torr. | Houghton's flatsedge | Endangered |
| CYOD (CYEN) | Cyperus odoratus L. (Cyperus engelmannii Steud.) | Engelmann's flatsedge | Rare |
| CYPO | Cyperus polystachyos Rottb. | many-spiked flatsedge | Extirpated |
| CYRE3 | Cyperus refractus Engelm. ex Boeckeler | reflexed flatsedge | Endangered |
| CYRE5 | Cyperus retrorsus Chapm. | retrorse flatsedge | Extirpated |
| CYSC3 | Cyperus schweinitzii Torr. | Schweinitz's flatsedge | Rare |
| CYCA5 | Cypripedium candidum Muhl. ex Willd. | small white lady's-slipper | Extirpated |
| CYPA19 | Cypripedium parviflorum Salisb. | small yellow lady's-slipper | Endangered |
| CYPAP3 (CYPU10) | Cypripedium parviflorum Salisb. var. pubescens (Willd.) Knight (Cypripedium pubescens Willd.) | large yellow lady's slipper | Vulnerable |
| CYRE6 | Cypripedium reginae Walter | showy lady's-slipper | Threatened |
| CYLA4 | Cystopteris laurentiana (Weath.) Blasdell | Laurentian bladder fern | Endangered |
| DAFRF (POFR4) | Dasiphora fruticosa (L.) Rydb. ssp. floribunda (Pursh) Kartesz (Potentilla fruticosa auct. non L.) | shrubby cinquefoil | Endangered |
| DEEX | Delphinium exaltatum Aiton | tall larkspur | Endangered |
| DESE | Desmodium sessilifolium (Torr.) Torr. & A. Gray | sessile-leaved tick-trefoil | Extirpated |
| DIOB3 | Diarrhena obovata (Gleason) Brandenburg | American beakgrain | Endangered |
| DIEX | Dicentra eximia (Ker Gawl.) Torr. | wild bleeding-hearts | Endangered |
| DIDID (PAAN10) | Dichanthelium dichotomum (L.) Gould var. dichotomum (Panicum annulum Ashe) | annulus panic-grass | Endangered |
| PALU4 | Panicum lucidum Ashe | shining panic-grass | Endangered |
| DILA9 (PALA15) | Dichanthelium laxiflorum (Lam.) Gould (Panicum laxiflorum Lam.) | panic-grass | Endangered |
| DILE2 (PALE7) | Dichanthelium leibergii (Vasey) Freckmann (Panicum leibergii (Vasey) Scribn.) | Leiberg's panic-grass | Extirpated |
| DIOLS (PASC10) | Dichanthelium oligosanthes (Schult.) Gould var. scribnerianum (Nash) Gould (Panicum scoparium S. Watson ex Nash, non Lam.) | velvety panic-grass | Endangered |
| DIOVA (PACO20) | Dichanthelium ovale (Elliot) Gould & C.A. Clark var. addisonii (Nash) Gould & C.A. Clark (Panicum commonsianum Ashe) | cloaked panic-grass | Extirpated |
| DISAP (PACOE) | Dichanthelium sabulorum (Lam.) Gould & C.A. Clark var. patulum (Scribn. & Merr.) Gould & C.A. Clark (Panicum commonsianum Ashe var. euchlamydeum (Shinners) Pohl) | panic-grass | Endangered |
| DISP4 (PASP9) | Dichanthelium spretum (Schult.) Freckmann (Panicum spretum Schult. | acuminate dichanthelium) | Endangered |
| DIXA (PAXA4) | Dichanthelium xanthophysum (A. Gray) Freckmann (Panicum xanthophysum A. Gray) | slender panic-grass | Endangered |
| DICO6 | Digitaria cognata (Schult.) Pilg. | fall witchgrass | Threatened |
| DISP | Distichlis spicata (L.) Greene | sea-shore salt-grass | Extirpated |
| DOAM | Dodecatheon amethystinum (Fassett) Fassett | jeweled shooting-star | Threatened |
| DOME | Dodecatheon meadia L. | common shooting-star | Endangered |
| DRRE2 | Draba reptans (Lam.) Fernald | Carolina whitlow-grass | Extirpated |
| DRCA3 | Dryopteris campyloptera Clarkson | mountain wood fern | Endangered |
| DRCE | Dryopteris celsa (Wm. Palmer) Knowlt., Palmer & Pollard ex Small | log fern | Endangered |
| DRCL | Dryopteris clintoniana (D.C. Eaton) Dowell | Clinton's shield fern | Threatened |
| ECLA | Echinacea laevigata (C.L. Boynt. & Beadle) S.F. Blake | smooth coneflower | Extirpated |
| ECWA | Echinochloa walteri (Pursh) A. Heller | Walter's barnyard-grass | Endangered |
| ELAM3 | Elatine americana (Pursh) Arn. | long-stemmed water-wort | Endangered |
| ELMI | Elatine minima (Nutt.) Fisch. & C.A. Mey. | small waterwort | Rare |
| ELCO2 | Eleocharis compressa Sull. | flat-stemmed spike-rush | Endangered |
| ELEL4 | Eleocharis elliptica Kunth | slender spike-rush | Endangered |
| ELCA2 (ELGE) | Eleocharis geniculata (L.) Roem. & Schult. (Eleocharis caribaea (Rottb.) S.F. Blake) | capitate spike-rush | Endangered |
| ELIN | Eleocharis intermedia Schult. | matted spike-rush | Threatened |
| ELOB2 (ELOBP) | Eleocharis obtusa (Willd.) Schult. (Eleocharis obtusa (Willd.) Schult. var. peasei Svens.) | spike-rush | Endangered |
| ELOL | Eleocharis olivacea Torr. | capitate spike-rush | Rare |
| ELPA5 | Eleocharis parvula (Roem. & Schult.) Link ex Bluff, Nees & Schauer | dwarf spike-rush | Endangered |
| ELQU | Eleocharis quadrangulata (Michx.) Roem. & Schult. | four-angled spike-rush | Endangered |
| ELQU2 (ELPAF) | Eleocharis quinqueflora (Hartmann) O. Schwarz (Eleocharis pauciflora (Lightf.) Link var. fernaldii Svens.) | few-flowered spike-rush | Endangered |
| ELRO | Eleocharis robbinsii Oakes | Robin's spike-rush | Threatened |
| ELRO2 | Eleocharis rostellata (Torr.) Torr. | beaked spike-rush | Endangered |
| ELTEV | Eleocharis tenuis (Willd.) Schult. var. verrucosa (Svens.) Svens. | slender spike-rush | Endangered |
| ELTR5 | Eleocharis tricostata Torr. | three-ribbed spike-rush | Extirpated |
| ELTU | Eleocharis tuberculosa (Michx.) Roem. & Schult. | long-tubercled spike-rush | Extirpated |
| ELCA3 | Elephantopus carolinianus Raeusch. | elephant's foot | Endangered |
| ELNY | Ellisia nyctelea (L.) L. | ellisia | Threatened |
| ELSC | Elodea schweinitzii (Planch.) Caspary | Schweinitz's waterweed | Extirpated |
| EPST | Epilobium strictum Muhl. ex Spreng. | downey willow-herb | Endangered |
| EQFE | Equisetum × ferrissii Clute (pro sp.) [hyemale × laevigatum] | scouring rush | Endangered |
| EQVA | Equisetum variegatum Schleich. ex F. Weber & D. Mohr | variegated horsetail | Endangered |
| ERBU | Erigenia bulbosa (Michx.) Nutt. | harbinger-of-spring | Threatened |
| ERDE5 | Eriocaulon decangulare L. | ten-angle pipewort | Extirpated |
| ERPA4 | Eriocaulon parkeri B.L. Rob. | Parker's pipewort | Extirpated |
| ERGR8 | Eriophorum gracile W.D.J. Koch | slender cotton-grass | Endangered |
| ERTE12 | Eriophorum tenellum Nutt. | rough cotton-grass | Endangered |
| ERVI9 | Eriophorum viridicarinatum (Engelm.) Fernald | thin-leaved cotton-grass | Threatened |
| ERAQ | Eryngium aquaticum L. | marsh eryngo | Extirpated |
| EURA5 (LERA4) | Eubotrys racemosa (L.) Nutt. (Leucothoe racemosa (L.) A. Gray) | swamp dog-hobble | Threatened |
| EUAL2 | Eupatorium album L. | white thoroughwort | Extirpated |
| EULE | Eupatorium leucolepis (DC.) Torr. & A. Gray | white-bracted thoroughwort | Extirpated |
| EUIP | Euphorbia ipecacuanhae L. | wild ipecac | Endangered |
| EUPU4 | Euphorbia purpurea (Raf.) Fernald | glade spurge | Endangered |
| EUSP (EUOB3) | Euphorbia spathulata Lam. (Euphorbia obtusata Pursh) | blunt-leaved spurge | Endangered |
| EUSP3 (ASSP11) | Eurybia spectabilis (Aiton) G.L. Nesom (Aster spectabilis Aiton) | low showy aster | Endangered |
| EUCA26 (EUTE7) | Euthamia caroliniana (L.) Greene ex Porter & Britton (Euthamia tenuifolia (Pursh) Nutt.) | grass-leaved goldenrod | Threatened |
| FEPA2 | Festuca paradoxa Desv. | cluster fescue | Endangered |
| FIAN | Fimbristylis annua (All.) Roem. & Schult. | annual fimbry | Threatened |
| FIPU | Fimbristylis puberula (Michx.) Vahl | hairy fimbry | Extirpated |
| FRCA2 | Frasera caroliniensis Walter | American columbo | Endangered |
| FRPR | Fraxinus profunda (Bush) Bush | pumpkin ash | Endangered |
| GARE2 | Galactia regularis (L.) Britton, Sterns & Poggenb. | eastern milk-pea | Extirpated |
| GAVO | Galactia volubilis (L.) Britton | downy milk-pea | Extirpated |
| GALA2 | Galium labradoricum (Wiegand) Wiegand | Labrador marsh bedstraw | Endangered |
| GAHI2 | Gaultheria hispidula (L.) Muhl. ex Bigelow | creeping snowberry | Rare |
| GABR5 | Gaylussacia brachycera (Michx.) A. Gray | box huckleberry | Endangered |
| GADU | Gaylussacia dumosa (Andrews) Torr. & A. Gray | dwarf huckleberry | Endangered |
| GEAL4 | Gentiana alba Muhl. ex Nutt. | yellow gentian | Extirpated |
| GECA10 | Gentiana catesbaei Walter | Elliott's gentian | Extirpated |
| GESA | Gentiana saponaria L. | soapwort gentian | Endangered |
| GEVI5 | Gentiana villosa L. | striped gentian | Endangered |
| GEVIV3 (GEPR6) | Gentianopsis virgata (Raf.) Holub ssp. virgata (Gentianopsis procera (T. Holm) Ma) | lesser fringed gentian | Extirpated |
| GEBI2 | Geranium bicknellii Britton | cranesbill | Endangered |
| GLBO | Glyceria borealis (Nash) Batchelder | small-floating manna-grass | Threatened |
| GLOB | Glyceria obtusa (Muhl.) Trin. | blunt manna-grass | Endangered |
| GOTE | Goodyera tesselata Lodd. | checkered rattlesname-plantain | Threatened |
| GRAU | Gratiola aurea Pursh | golden-pert | Endangered |
| GYAP | Gymnocarpium appalachianum Pryer | Appalachian oak fern | Endangered |
| GYHE3 (GYHE) | Gymnocarpium × heterosporum W.H. Wagner (pro sp.) [appalachianum × robertianum] (Gymnocarpium heterosporum W.H. Wagner) | oak fern | Extirpated |
| GYAM | Gymnopogon ambiguus (Michx.) Britton, Sterns & Poggenb. | broad-leaved beardgrass | Extirpated |
| HEBI2 | Helianthemum bicknellii Fernald | Bicknell's hoary rockrose | Endangered |
| HEAN2 | Helianthus angustifolius L. | swamp sunflower | Extirpated |
| HEMU5 | Heteranthera multiflora (Griseb.) Horn | multiflowered mud-plantain | Endangered |
| HIGR5 (HITR5) | Hieracium greenii Porter & Britton (Hieracium traillii Greene) | Maryland hawkweed | Endangered |
| HIOD | Hierochloe odorata (L.) P. Beauv. | vanilla sweet-grass | Endangered |
| HOPU | Hordeum pusillum Nutt. | little barley | Extirpated |
| HOIN | Hottonia inflata Elliot | American featherfoil | Extirpated |
| HOSE2 (HEMI15) | Houstonia serpyllifolia Michx. (Hedyotis michauxii Fosberg) | creeping bluets | Extirpated |
| HUPO2 | Huperzia porophila (Lloyd & Underw.) Holub | rock clubmoss | Endangered |
| HUSE | Huperzia selago (L.) Bernh. ex Schrank & Mart. | mountain clubmoss | Extirpated |
| HYCA | Hydrastis canadensis L. | goldenseal | Vulnerable |
| HYUM | Hydrocotyle umbellata L. | many-flowered pennywort | Extirpated |
| HYMA | Hydrophyllum macrophyllum Nutt. | large-leafed water-leaf | Endangered |
| HYTE9 (SETE) | Hylotelephium telephioides (Michx.) H. Ohba (Sedum telephioides Michx.) | Allegheny stonecrop | Rare |
| HYAD | Hypericum adpressum Raf. ex W. Bartram | creeping St. John's-wort | Extirpated |
| HYCR3 (HYST3) | Hypericum crux-andreae (L.) Crantz (Hypericum stans (Michx. ex Willd.) P. Adams & N. Robson) | St. Peter's-wort | Extirpated |
| HYDE | Hypericum densiflorum Pursh | bushy St. John's-wort | Threatened |
| HYDE2 | Hypericum denticulatum Walter | coppery St. John's-wort | Extirpated |
| HYDR | Hypericum drummondii (Grev. & Hook.) Torr. & A. Gray | nits-and-lice | Extirpated |
| HYGY | Hypericum gymnanthum Engelm. & A. Gray | clasping-leaved St. John's-wort | Extirpated |
| HYMA2 | Hypericum majus (A. Gray) Britton | larger Canadian St. John's-wort | Threatened |
| ILGL | Ilex glabra (L.) A. Gray | ink-berry | Extirpated |
| ILOP | Ilex opaca Aiton | American holly | Threatened |
| IOPI | Iodanthus pinnatifidus (Michx.) Steud. | purple rocket | Endangered |
| IRCR | Iris cristata Aiton | crested dwarf iris | Endangered |
| IRPR | Iris prismatica Pursh ex Ker Gawl. | slender blue iris | Endangered |
| IRVE | Iris verna L. | dwarf iris | Endangered |
| IRVI | Iris virginica L. | Virginia blue flag | Endangered |
| ISME2 | Isotria medeoloides (Pursh) Raf. | small-whorled pogonia | Endangered |
| ITVI | Itea virginica L. | Virginia willow | Extirpated |
| JUALN (JUAL) | Juncus alpinoarticulatus Chaix ssp. nodulosus (Wahlenb.) Hämet-Ahti (Juncus alpinus auct. non Vill.) | Richardson's rush | Threatened |
| JUARL (JUBA) | Juncus arcticus Willd. ssp. littoralis (Engelm.) Hultén (Juncus balticus Willd.) | Baltic rush | Threatened |
| JUBI | Juncus biflorus Elliot | grass-leaved rush | Threatened |
| JUBR | Juncus brachycarpus Engelm. | short-fruited rush | Endangered |
| JUBR2 | Juncus brachycephalus (Engelm.) Buchenau | small-headed rush | Threatened |
| JUDI | Juncus dichotomus Elliot | forked rush | Endangered |
| JUFI | Juncus filiformis L. | thread rush | Rare |
| JUGR | Juncus greenei Oakes & Tuck. | Greene's rush | Extirpated |
| JUGY | Juncus gymnocarpus Coville | Coville's rush | Rare |
| JUMI2 | Juncus militaris Bigelow | bayonet rush | Endangered |
| JUSC | Juncus scirpoides Lam. | scirpus-like rush | Endangered |
| JUTO | Juncus torreyi Coville | Torrey's rush | Endangered |
| KOMA (KOCR) | Koeleria macrantha (Ledeb.) Schult. (Koeleria cristata auct. non Pers. p.p.) | Junegrass | Extirpated |
| LAJA | Lathyrus japonicus Willd. | beach peavine | Threatened |
| LAOC2 | Lathyrus ochroleucus Hook. | wild-pea | Threatened |
| LAPA4 | Lathyrus palustris L. | marsh pea | Endangered |
| LEGR | Ledum groenlandicum Oeder | common labrador-tea | Rare |
| LEBU | Leiophyllum buxifolium (Bergius) Elliot | sand-myrtle | Extirpated |
| LEOB2 | Lemna obscura (Austin) Daubs | little water duckweed | Extirpated |
| LEVA | Lemna valdiviana Phil. | pale duckweed | Extirpated |
| LEAN | Lespedeza angustifolia (Pursh) Elliot | narrowleaf bush clover | Endangered |
| LEST5 | Lespedeza stuevei Nutt. | tall bushclover | Extirpated |
| LICA16 | Ligusticum canadense (L.) Britton | lovage | Endangered |
| LIAU6 | Limosella australis R. Br. | awl-shaped mudwort | Extirpated |
| LIBO3 | Linnaea borealis L. | twinflower | Threatened |
| LIIN | Linum intercursum E.P. Bicknell | sandplain wild flax | Endangered |
| LISU4 | Linum sulcatum Riddell | grooved yellow flax | Endangered |
| LIMI12 (HEMI5) | Lipocarpha micrantha (Vahl) G. Tucker (Hemicarpha micrantha (Vahl) Pax) | common hemicarpa | Endangered |
| LIAU3 | Listera australis Lindl. | southern twayblade | Endangered |
| LICO6 | Listera cordata (L.) R. Br. | heart-leaved twayblade | Endangered |
| LISM | Listera smallii Wiegand | kidney-leaved twayblade | Endangered |
| LICA13 | Lithospermum caroliniense (Walter ex J.F. Gmel.) MacMill. | hispid gromwell | Endangered |
| LILA2 | Lithospermum latifolium Michx. | American gromwell | Endangered |
| LODO | Lobelia dortmanna L. | water lobelia | Threatened |
| LOKA | Lobelia kalmii L. | brook lobelia | Endangered |
| LONU | Lobelia nuttallii Schult. | Nuttall's lobelia | Extirpated |
| LOPU | Lobelia puberula Michx. | downy lobelia | Endangered |
| LOHI | Lonicera hirsuta Eaton | hairy honeysuckle | Endangered |
| LOOB | Lonicera oblongifolia (Goldie) Hook. | swamp fly honeysuckle | Endangered |
| LOVI | Lonicera villosa (Michx.) Schult. | mountain fly honeysuckle | Endangered |
| LUDE4 | Ludwigia decurrens Walter | upright primrose-willow | Endangered |
| LUPO | Ludwigia polycarpa Short & Peter | false loosestrife seedbox | Endangered |
| LUSP | Ludwigia sphaerocarpa Elliot | spherical-fruited seedbox | Extirpated |
| LUPE3 | Lupinus perennis L. | wild blue lupine | Rare |
| LUBU | Luzula bulbosa (Alph. Wood) Smyth & Smyth | wood-rush | Endangered |
| LYAL5 | Lycopodiella alopecuroides (L.) Cranfill | foxtail clubmoss | Endangered |
| LYAP4 | Lycopodiella appressa (Chapm.) Cranfill | southern bog clubmoss | Threatened |
| LYSA (DISA11) | Lycopodium sabinifolium Willd. (Diphasiastrum sabinifolium (Willd.) Holub) | fir clubmoss | Extirpated |
| LYRU | Lycopus rubellus Moench | taper-leaved bugle-weed | Endangered |
| LYPA3 | Lygodium palmatum (Bernh.) Sw. | Hartford fern | Rare |
| LYMA2 | Lyonia mariana (L.) D. Don | stagger-bush | Endangered |
| LYHY | Lysimachia hybrida Michx. | lance-leaved loosestrife | Threatened |
| LYAL4 | Lythrum alatum Pursh | winged loosestrife | Endangered |
| MATR | Magnolia tripetala (L.) L. | umbrella magnolia | Rare |
| MAVI2 | Magnolia virginiana L. | sweet bay magnolia | Threatened |
| MABA6 | Malaxis bayardii Fernald | Bayard's malaxis | Rare |
| MABR5 | Malaxis brachypoda (A. Gray) Fernald | white adder's-mouth | Endangered |
| MAGR7 | Marshallia grandiflora Beadle & F.E. Boynt. | large-flowered marshallia | Endangered |
| MAOB2 | Matelea obliqua (Jacq.) Woodson | oblique milkvine | Endangered |
| MECO | Meehania cordata (Nutt.) Britton | heart-leafed meehania | Endangered |
| MENI | Melica nitens (Scribn.) Nutt. ex Piper | three-flowered meltic-grass | Threatened |
| MEPI2 | Menziesia pilosa (Michx. ex Lam.) Juss. ex Pers. | minniebush | Rare |
| MIMI6 | Micranthemum micranthemoides (Nutt.) Wettst. | Nuttall's mud-flower | Extirpated |
| MIGL5 | Minuartia glabra (Michx.) Mattf. | Applachian sandwort | Threatened |
| MINU3 | Mitella nuda L. | naked bishop's-cap | Endangered |
| MOPU | Monarda punctata L. | spotted bee-balm | Endangered |
| MOCH | Montia chamissoi (Ledeb. ex Spreng.) Greene | Chamisso's miner's-lettuce | Endangered |
| MUCA2 | Muhlenbergia capillaris (Lam.) Trin. | short muhly | Extirpated |
| MUUN | Muhlenbergia uniflora (Muhl.) Fernald | false dropseed muhly | Endangered |
| MYGA | Myrica gale L. | sweet bayberry | Threatened |
| MYFA2 | Myriophyllum farwellii Morong | Farwell's water-milfoil | Endangered |
| MYHE2 | Myriophyllum heterophyllum Michx. | broad-leaved water-milfoil | Endangered |
| MYSI (MYEX) | Myriophyllum sibiricum Kom. (Myriophyllum exalbescens Fernald) | northern water-milfoil | Endangered |
| MYTE | Myriophyllum tenellum Bigelow | slender water-milfoil | Threatened |
| MYVE3 | Myriophyllum verticillatum L. | whorled water-milfoil | Endangered |
| NAGR | Najas gracillima (A. Braun ex Engelm.) Magnus | bushy naiad | Threatened |
| NAMA | Najas marina L. | holly-leaved naiad | Endangered |
| NELU | Nelumbo lutea Willd. | American lotus | Endangered |
| NYCO | Nymphoides cordata (Elliot) Fernald | floating-heart | Threatened |
| OCNE2 (ASNE) | Oclemena nemoralis (Aiton) Greene (Aster nemoralis Aiton) | bog aster | Endangered |
| OEAR | Oenothera argillicola Mack. | shale-barren evening-primrose | Threatened |
| OLRIR (SORI2) | Oligoneuron rigidum (L.) Small var. rigidum (Solidago rigida L.) | stiff goldenrod | Endangered |
| ONBEH (ONHI) | Onosmodium bejariense DC. ex A. DC. var. hispidissimum (Mack.) B.L. Turner (Onosmodium hispidissimum Mack.) | false gromwell | Endangered |
| ONVI2 | Onosmodium virginianum (L.) A. DC. | Virginia false-gromwell | Extirpated |
| OPEN | Ophioglossum engelmannii Prantl | limestone adder's-tongue | Endangered |
| OPVU (OPPY3) | Ophioglossum vulgatum L (Ophioglossum pycnostichum (Fernald) A. Löve & D. Löve) | southeastern adder's tongue | Extirpated |
| OPHU | Opuntia humifusa (Raf.) Raf. | prickly-pear cactus | Rare |
| ORAQ | Orontium aquaticum L. | golden club | Rare |
| PAAN6 (SEAN2) | Packera anonyma (Alph. Wood) W.A. Weber & A. Löve (Senecio anonymus Alph. Wood) | plain ragwort | Rare |
| PAAN7 (SEAN3) | Packera antennariifolia (Britton) W.A. Weber & A. Löve (Senecio antennariifolius Britton) | cat's-paw ragwort | Endangered |
| PAPL12 (SEPL) | Packera plattensis (Nutt.) W.A. Weber & A. Löve (Senecio plattensis Nutt.) | prairie ragwort | Extirpated |
| PAQU | Panax quinquefolius L. | ginseng | Vulnerable |
| PAAMA2 | Panicum amarum Elliot var. amarulum (Hitchc. & Chase) P.G. Palmer | southern sea-beach panic-grass | Endangered |
| PAPH (PATU) | Panicum philadelphicum Bernh. ex Trin. (Panicum tuckermanii Fernald) | Tuckerman's panicgrass | Threatened |
| PAGL3 | Parnassia glauca Raf. | Carolina grass-of-parnassus | Endangered |
| PAFAN | Paronychia fastigiata (Raf.) Fernald var. nuttallii (Small) Fernald | forked chickweed | Endangered |
| PAIN3 | Parthenium integrifolium L. | American fever-few | Extirpated |
| PAFL4 (PAFLG) | Paspalum floridanum Michx. (Paspalum floridanum Michx. var. glabratum Engelm. ex Vasey) | Florida beadgrass | Extirpated |
| PALU2 | Passiflora lutea L. | passion-flower | Endangered |
| PACA | Paxistima canbyi A. Gray | Canby's mountain-lover | Endangered |
| PELA2 | Pedicularis lanceolata Michx. | swamp lousewort | Endangered |
| PHTE18 (TATE) | Phemeranthus teretifolius (Pursh) Raf. (Talinum teretifolium Pursh) | round-leaved fame-flower | Threatened |
| PHLA13 (PHOV) | Phlox latifolia Michx. (Phlox ovata auct. non L.) | mountain phlox | Endangered |
| PHPI | Phlox pilosa L. | downy phlox | Endangered |
| PHSUB2 | Phlox subulata L. ssp. brittonii (Small) Wherry | moss pink | Endangered |
| PHLE14 (PHSE9) | Phoradendron leucarpum (Raf.) Reveal & M.C. Johnst. (Phoradendron serotinum (Raf.) M.C. Johnst.) | Christmas mistletoe | Extirpated |
| PHLA3 | Phyla lanceolata (Michx.) Greene | fog-fruit | Rare |
| PHCA9 | Phyllanthus caroliniensis Walter | Carolina leaf-flower | Endangered |
| PHVI5 | Physalis virginiana Mill. | Virginia ground-cherry | Endangered |
| PIPU7 (ORPU4) | Piptatherum pungens (Torr. ex Spreng.) Dorn (Oryzopsis pungens (Torr. ex Spreng.) Hitchc.) | slender mountain-ricegrass | Endangered |
| PIAV | Piptochaetium avenaceum (L.) Parodi | black oatgrass | Extirpated |
| PLCI2 | Platanthera ciliaris (L.) Lindl. | yellow fringed-orchid | Threatened |
| PLCR | Platanthera cristata (Michx.) Lindl. | crested yellow orchid | Extirpated |
| PLDI3 | Platanthera dilatata (Pursh) Lindl. ex Beck | leafy white orchid | Endangered |
| PLHO3 | Platanthera hookeri (Torr. ex A. Gray) Lindl. | Hooker's orchid | Endangered |
| PLHY2 | Platanthera hyperborea (L.) Lindl. | leafy northern green orchid | Endangered |
| PLLE2 | Platanthera leucophaea (Nutt.) Lindl. | prairie white-fringed orchid | Extirpated |
| PLPE | Platanthera peramoena (A. Gray) A. Gray | purple fringeless orchid | Threatened |
| PLOD | Pluchea odorata (L.) Cass. | shrubby camphor-weed | Endangered |
| POAU | Poa autumnalis Muhl. ex Elliot | autumn bluegrass | Endangered |
| POPA | Poa paludigena Fernald & Wiegand | bog bluegrass | Threatened |
| POSA (POLA2) | Poa saltuensis Fernald & Wiegand (Poa languida Hitchc.) | woodland bluegrass | Threatened |
| POVA5 | Polemonium vanbruntiae Britton | Jacob's-ladder | Endangered |
| POCR | Polygala cruciata L. | cross-leaved milkwort | Endangered |
| POCU5 | Polygala curtissii A. Gray | Curtis's milkwort | Endangered |
| POIN4 | Polygala incarnata L. | pink milkwort | Endangered |
| POLU | Polygala lutea L. | yellow milkwort | Extirpated |
| POPO | Polygala polygama Walter | bitter milkwort | Endangered |
| POAR4 | Polygonella articulata (L.) Meisn. | eastern jointweed | Endangered |
| POCA8 | Polygonum careyi Olney | Carey's smartweed | Endangered |
| PORA3 | Polygonum ramosissimum Michx. | bushy knotweed | Extirpated |
| POSE6 (POSEI) | Polygonum setaceum Baldw. (Polygonum setaceum Baldw. var. interjectum Fernald) | swamp smartweed | Endangered |
| POBR4 | Polystichum braunii (Spenner) Fée | Braun's holly fern | Endangered |
| POBA2 | Populus balsamifera L. | balsam poplar | Endangered |
| POHE4 | Populus heterophylla L. | swamp cottonwood | Extirpated |
| POAL8 | Potamogeton alpinus Balbis | northern pondweed | Extirpated |
| POCO12 | Potamogeton confervoides Rchb. | Tuckerman's pondweed | Threatened |
| POFR3 | Potamogeton friesii Rupr. | Fries' pondweed | Endangered |
| POGR8 | Potamogeton gramineus L. | grassy pondweed | Endangered |
| POHI4 | Potamogeton hillii Morong | Hill's pondweed | Endangered |
| POIL | Potamogeton illinoensis Morong | Illinois pondweed | Rare |
| POOA | Potamogeton oakesianus J.W. Robbins | Oakes' pondweed | Endangered |
| POOB2 | Potamogeton obtusifolius Mert. & W.D.J. Koch | blunt-leaved pondweed | Endangered |
| POPR5 | Potamogeton praelongus Wulfen | white-stemmed pondweed | Endangered |
| POPU6 | Potamogeton pulcher Tuck. | spotted pondweed | Endangered |
| PORI2 | Potamogeton richardsonii (Benn.) Rydb. | red-head pondweed | Threatened |
| PORO2 | Potamogeton robbinsii Oakes | flat-leaved pondweed | Rare |
| POST2 | Potamogeton strictifolius Benn. | narrow-leaved pondweed | Endangered |
| POTE4 | Potamogeton tennesseensis Fernald | Tennessee pondweed | Endangered |
| POVA3 | Potamogeton vaseyi J.W. Robbins | Vasey's pondweed | Endangered |
| POZO | Potamogeton zosteriformis Fernald | flat-stem pondweed | Rare |
| POPA15 | Potentilla paradoxa Nutt. | bushy cinquefoil | Endangered |
| PRCR | Prenanthes crepidinea Michx. | rattlesnake-root | Endangered |
| PRRA | Prenanthes racemosa Michx. | glaucous rattlesnake-root | Extirpated |
| PRPE | Proserpinaca pectinata Lam. | comb-leaved mermaid-weed | Extirpated |
| PRAL5 | Prunus alleghaniensis Porter | Allegheny plum | Threatened |
| PRMA2 | Prunus maritima Marsh. | beach plum | Endangered |
| PRPU3 | Prunus pumila L. | sand cherry | Rare |
| PTTR | Ptelea trifoliata L. | common hop-tree | Threatened |
| PTCA | Ptilimnium capillaceum (Michx.) Raf. | mock bishop-weed | Extirpated |
| PYPY | Pycnanthemum pycnanthemoides (Leavenworth) Fernald | southern mountain-mint | Endangered |
| PYTO | Pycnanthemum torrei Benth. | Torrey's mountain-mint | Endangered |
| PYVEP (PYPI) | Pycnanthemum verticillatum (Michx.) Pers. var. pilosum (Nutt.) Cooperr. (Pycnanthemum pilosum Nutt.) | hairy mountain-mint | Extirpated |
| PYPU | Pyrularia pubera Michx. | buffalo nut | Rare |
| QUFA | Quercus falcata Michx. | southern red oak | Endangered |
| QUPH | Quercus phellos L. | willow oak | Endangered |
| QUSH | Quercus shumardii Buckley | Shumard's oak | Endangered |
| RAFA | Ranunculus fascicularis Muhl. ex Bigelow | tufted buttercup | Endangered |
| RAFL2 | Ranunculus flammula L. | creeping spearwort | Extirpated |
| RAHE2 | Ranunculus hederaceus L. | long-stalked crowfoot | Extirpated |
| RALO2 | Ranunculus longirostris Godr. | eastern white water-crowfoot | Threatened |
| RAPU | Ranunculus pusillus Poir. | low spearwort | Endangered |
| RATR | Ranunculus trichophyllus Chaix | white water-crowfoot | Rare |
| RAPI | Ratibida pinnata (Vent.) Barnhart | prairie coneflower | Extirpated |
| RHLA | Rhamnus lanceolata Pursh | lanceolate buckthorn | Endangered |
| RHMA | Rhexia mariana L. | Maryland meadow-beauty | Endangered |
| RHRO3 (SERO2) | Rhodiola rosea L. (Sedum rosea (L.) Scop.) | roseroot stonecrop | Endangered |
| RHAT | Rhododendron atlanticum (Ashe) Rehder | dwarf azalea | Endangered |
| RHCA4 | Rhododendron calendulaceum (Michx.) Torr. | flame azalea | Extirpated |
| RHCA11 | Rhynchospora capillacea Torr. | capillary beaked-rush | Endangered |
| RHFU | Rhynchospora fusca (L.) W.T. Aiton | brown beaked-rush | Extirpated |
| RHGR | Rhynchospora gracilenta A. Gray | beaked-rush | Extirpated |
| RILA | Ribes lacustre (Pers.) Poir. | bristly black currant | Endangered |
| RIMI | Ribes missouriense Nutt. | Missouri gooseberry | Endangered |
| RITR | Ribes triste Pall. | red currant | Threatened |
| RORA | Rotala ramosior (L.) Koehne | tooth-cup | Rare |
| RUCU | Rubus cuneifolius Pursh | sand blackberry | Endangered |
| RUCA4 | Ruellia caroliniensis (J.F. Gmel.) Steud. | Carolina petunia | Extirpated |
| RUHU | Ruellia humilis Nutt. | fringed-leaved petunia | Endangered |
| RUST2 | Ruellia strepens L. | limestone petunia | Threatened |
| RUHA2 | Rumex hastatulus Baldw. | heart sorrel | Extirpated |
| SACA26 | Sabatia campanulata (L.) Torr. | slender marsh pink | Extirpated |
| SAGI (ERGI) | Saccharum giganteum (Walter) Pers. (Erianthus giganteus (Walter) P. Beauv.) | sugarcane plumegrass | Extirpated |
| SACAS | Sagittaria calycina Engelm. var. spongiosa Engelm. | long-lobed arrow-head | Endangered |
| SAFI2 (SAST4) | Sagittaria filiformis J.G. Sm. (Sagittaria stagnorum Small) | arrow-head | Extirpated |
| SASU | Sagittaria subulata (L.) Buchenau | subulate arrow-head | Rare |
| SACA4 | Salix candida Flueggé ex Willd. | hoary willow | Endangered |
| SACA5 | Salix caroliniana Michx. | Carolina willow | Endangered |
| SAPE2 | Salix pedicellaris Pursh | bog-willow | Endangered |
| SAPE5 | Salix petiolaris Sm. | slender willow | Endangered |
| SASE2 | Salix serissima (L.H. Bailey) Fernald | autumn willow | Threatened |
| SAVAP (SAPA9) | Samolus valerandi L. ssp. parviflorus (Raf.) Hultén (Samolus parviflorus Raf.) | pineland pimpernel | Endangered |
| SAMI6 | Saxifraga micranthidifolia (Haw.) Steud. | lettice saxofrage | Rare |
| SCPA2 | Scheuchzeria palustris L. | pod-grass | Endangered |
| SCLI11 (SCSCL) | Schizachyrium littorale (Nash) E.P. Bicknell (Schizachyrium scoparium (Michx.) Nash var. littorale (Nash) Gould) | seaside bluestem | Rare |
| SCACA (SCAC) | Schoenoplectus acutus (Muhl. ex Bigelow) A. Löve & D. Löve var. acutus (Scirpus acutus Muhl. ex Bigelow) | hard-stemmed bullrush | Endangered |
| SCFL11 (SCFL) | Schoenoplectus fluviatilis (Torr.) M.T. Strong (Scirpus fluviatilis (Torr.) A. Gray) | river bullrush | Rare |
| SCHE5 (SCHE) | Schoenoplectus heterochaetus (Chase) Soják (Scirpus heterochaetus Chase) | slender bullrush | Extirpated |
| SCSM2 (SCSM) | Schoenoplectus smithii (A. Gray) Soják (Scirpus smithii A. Gray) | Smith's bullrush | Endangered |
| SCTO3 (SCTO) | Schoenoplectus torreyi (Olney) Palla (Scirpus torreyi Olney) | Torrey's bullrush | Endangered |
| SCAN5 | Scirpus ancistrochaetus Schuyler | northeastern bullrush | Threatened |
| SCPE3 | Scirpus pedicellatus Fernald | stalked bullrush | Threatened |
| SCMI4 | Scleria minor W. Stone | minor nutrush | Endangered |
| SCPA5 | Scleria pauciflora Muhl. ex Willd. | few-flowered nutrush | Threatened |
| SCRE | Scleria reticularis Michx. | reticulated nutrush | Endangered |
| SCVE2 | Scleria verticillata Muhl. ex Willd. | whorled nutrush | Endangered |
| SCSA5 | Scutellaria saxatilis Riddell | rock skullcap | Endangered |
| SCSE5 | Scutellaria serrata Andrews | showy skullcap | Endangered |
| SELI5 (ASSO2) | Sericocarpus linifolius (L.) Britton, Sterns & Poggenb. (Aster solidagineus Michx.) | narrow-leaved white-topped aster | Endangered |
| SHCA | Shepherdia canadensis (L.) Nutt. | Canada buffalo-berry | Endangered |
| SITR3 (POTR7) | Sibbaldiopsis tridentata (Aiton) Rydb. (Potentilla tridentata Aiton) | three-toothed cinquefoil | Endangered |
| SIHE3 | Sida hermaphrodita (L.) Rusby | sida | Endangered |
| SIAL3 | Sisyrinchium albidum Raf. | blue-eyed-grass | Extirpated |
| SIAT | Sisyrinchium atlanticum E.P. Bicknell | eastern blue-eyed grass | Endangered |
| SIFU2 (SIAR2) | Sisyrinchium fuscatum E.P. Bicknell (Sisyrinchium arenicola E.P. Bicknell) | sand blue-eyed grass | Extirpated |
| SMPS | Smilax pseudochina L. | long-stalked greenbrier | Extirpated |
| SOARH | Solidago arguta Aiton var. harrisii (Steele) Cronquist | Harris' goldenrod | Endangered |
| SOCU | Solidago curtisii Torr. & A. Gray | Curtis' goldenrod | Endangered |
| SOER | Solidago erecta Pursh | slender goldenrod | Endangered |
| SORO2 | Solidago roanensis Porter | Tennessee golden-rod | Rare |
| SOSIR2 (SOSPR4) | Solidago simplex Kunth ssp. randii (Porter) Ringius var. racemosa (Greene) Ringius (Solidago spathulata DC. var. racemosa (Greene) Gleason) | sticky goldenrod | Endangered |
| SODE3 | Sorbus decora (Sarg.) C.K. Schneid. | showy mountain-ash | Endangered |
| SPAN | Sparganium androcladum (Engelm.) Morong | branching bur-reed | Endangered |
| SPNA (SPMI) | Sparganium natans L.(Sparganium minimum Wallr.) | small bur-reed | Extirpated |
| SPBE2 | Spiraea betulifolia Pall. | dwarf spiraea | Threatened |
| SPVI2 | Spiraea virginiana Britton | Virginia spiraea | Extirpated |
| SPCA6 | Spiranthes casei Catling & Cruise | Case's ladies'-tresses | Endangered |
| SPMA5 | Spiranthes magnicamporum Sheviak | ladies'-tresses | Extirpated |
| SPOV | Spiranthes ovalis Lindl. | October ladies'-tresses | Endangered |
| SPRO | Spiranthes romanzoffiana Cham. | hooded ladies'-tresses | Endangered |
| SPTU | Spiranthes tuberosa Raf. | slender ladies'-tresses | Extirpated |
| SPVE | Spiranthes vernalis Engelm. & A. Gray | spring ladies'-tresses | Endangered |
| SPCL | Sporobolus clandestinus (Biehler) Hitchc. | rough dropseed | Endangered |
| SPCR | Sporobolus cryptandrus (Torr.) A. Gray | sand dropseed | Rare |
| SPHE | Sporobolus heterolepis (A. Gray) A. Gray | prairie dropseed | Endangered |
| STCO9 (STNU2) | Stachys cordata Riddell (Stachys nuttallii Shuttlw. ex Benth.) | Nuttall's hedge-nettle | Endangered |
| STHY3 | Stachys hyssopifolia Michx. | hyssop hedge-nettle | Extirpated |
| STAM2 | Streptopus amplexifolius (L.) DC. | white twisted-stalk | Endangered |
| STFIF (POFI2) | Stuckenia filiformis (Pers.) Böerner ssp. filiformis (Potamogeton filiformis Pers.) | threadleaf pondweed | Extirpated |
| STBI2 | Stylosanthes biflora (L.) Britton, Sterns & Poggenb. | pencil-flower | Endangered |
| SYBO2 (ASBO7) | Symphyotrichum boreale (Torr. & A. Gray) A. Löve & D. Löve (Aster borealis (Torr. & A. Gray) Prov.) | rush aster | Endangered |
| SYDE2 (ASDE9) | Symphyotrichum depauperatum (Fernald) G.L. Nesom (Aster depauperatus Fernald) | serpentine aster | Threatened |
| SYNON (ASNO2) | Symphyotrichum novi-belgii (L.) G.L. Nesom var. novi-belgii (Aster novi-belgii L.) | long-leaved aster | Threatened |
| SYPUP (ASFI5) | Symphyotrichum puniceum (L.) A. Löve & D. Löve var. puniceum (Aster firmus Nees) | shining aster | Threatened |
| TAMO | Taenidia montana (Mack.) Cronquist | mountain pimpernel | Endangered |
| THCO2 | Thalictrum coriaceum (Britton) Small | thick-leaved meadow-rue | Endangered |
| TIDI | Tipularia discolor (Pursh) Nutt. | crainfly orchid | Rare |
| TROH | Tradescantia ohiensis Raf. | Ohio spiderwort | Endangered |
| TRCA | Trautvetteria caroliniensis (Walter) Vail | Carolina tassel-rue | Rare |
| TRSE5 | Trichostema setaceum Houtt. | blue-curls | Endangered |
| TRRE2 | Trifolium reflexum L. | buffalo clover | Extirpated |
| TRVI3 | Trifolium virginicum Small ex Small & Vail | Kate's mountain clover | Endangered |
| TRPA28 (TRPA6) | Triglochin palustris L. (Triglochin palustre L., orth. var.) | marsh arrowgrass | Extirpated |
| TRNI2 | Trillium nivale Riddell | snow trillium | Rare |
| TRAN3 | Triosteum angustifolium L. | horse-gentian | Endangered |
| TRTR3 | Triphora trianthophora (Sw.) Rydb. | nodding pogonia | Endangered |
| TRPU4 | Triplasis purpurea (Walter) Chapm. | purple sandgrass | Endangered |
| TRDA3 | Tripsacum dactyloides (L.) L. | gamma grass | Endangered |
| TRSP2 | Trisetum spicatum (L.) K. Richt. | narrow false oats | Endangered |
| TRLA14 | Trollius laxus Salisb. | spreading globe flower | Endangered |
| UTGI (UTFI) | Utricularia gibba L. (Utricularia fibrosa Walter) | fibrous bladderwort | Extirpated |
| UTIN2 | Utricularia intermedia Hayne | flat-leaved bladderwort | Threatened |
| UTMI | Utricularia minor L. | lesser bladderwort | Threatened |
| UTPU | Utricularia purpurea Walter | purple bladderwort | Rare |
| UTRA | Utricularia radiata Small | floating bladderwort | Endangered |
| UTRE | Utricularia resupinata B.D. Greene ex Bigelow | northeastern bladderwort | Extirpated |
| UVPU2 | Uvularia puberula Michx. | mountain bellwort | Rare |
| VEGL | Vernonia glauca (L.) Willd. | tawny ironweed | Endangered |
| VINU | Viburnum nudum L. | possum haw viburnum | Endangered |
| VIOPA2 (VITR8) | Viburnum opulus L. var. americanum Aiton (Viburnum trilobum Marsh.) | highbush cranberry | Rare |
| VIBR | Viola brittoniana Pollard | coast violet | Endangered |
| VIPE2 | Viola pedatifida G. Don | prairie violet | Endangered |
| VIRE2 | Viola renifolia A. Gray | kidney-leaved white violet | Extirpated |
| VITR4 | Viola tripartita Elliot | three-parted violet | Extirpated |
| VICIB | Vitis cinerea (Engelm.) Engelm. ex Millard var. baileyana (Munson) Comeaux | possum grape | Endangered |
| VINO2 | Vitis × novae-angliae Fernald (pro sp.) [labrusca × riparia] | New England grape | Endangered |
| VIRU2 | Vitis rupestris Scheele | sand grape | Endangered |
| VIAP2 | Vittaria appalachiana Farrar & Mickel | Appalachian gametophyte fern | Threatened |
| WOGL2 | Wolffiella gladiata (Hegelm.) Hegelm. | bog mat | Rare |
| WOAR | Woodwardia areolata (L.) T. Moore | netted chain fern | Threatened |
| XYMO | Xyris montana Ries | yellow-eyed grass | Rare |
| XYTO | Xyris torta Sm. | yellow-eyed-grass | Threatened |
| ZIELG (ZIELG2) | Zigadenus elegans Pursh ssp. glaucus (Nutt.) Hultén (Zigadenus elegans Pursh var. glaucus (Nutt.) Cronquist) | death-camas | Endangered |
| ZIAQ | Zizania aquatica L. | Indian wild rice | Rare |