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Digital Atlas of the Virginia Flora

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  • Abdra brachycarpa (Nuttall ex Torrey & A. Gray) E.L. Greene (Short-fruited Whitlow-grass)
  • Abies balsamea (L.) Miller (Balsam Fir, Northern Balsam)
  • Abies fraseri (Pursh) Poiret (Fraser Fir, Southern Balsam)
  • Abietinella abietina (Hedw.) M. Fleisch.
  • Abutilon theophrasti Medik. (Velvetleaf)
  • Acalypha deamii (Weatherby) Ahles (Deam's Copperleaf, Big-seeded Copperleaf, Two-seeded Copperleaf)
  • Acalypha gracilens Gray (Slender Three-seeded Mercury, Short-stalk Copperleaf)
  • Acalypha ostryifolia Riddell (Hornbeam Copperleaf, Rough-pod Copperleaf)
  • Acalypha rhomboidea Raf. (Common Three-seeded Mercury, Common Copperleaf)
  • Acalypha virginica L. (Virginia Three-seeded Mercury, Virginia Copperleaf)
  • Acanthospermum australe (Loefl.) Kuntze (Paraguay Bur, Sheep Bur)
  • Acanthospermum hispidum DC. (Hispid Starbur)
  • Acaulon muticum (Hedw.) Mll. Hal. var. rufescens (A. Jaeger) H.A. Crum
  • Acaulon triquetrum (Spruce) Mll. Hal.
  • Acer campestre L. (Hedge Maple)
  • Acer floridanum (Chapm.) Pax. (Southern Sugar Maple, Florida Maple)
  • Acer ginnala Maxim. (Amur Maple)
  • Acer negundo L. var. negundo (Boxelder, Eastern Boxelder)
  • Acer nigrum Michx. f. (Black Maple)
  • Acer palmatum Thunb. (Japanese Maple)
  • Acer pensylvanicum L. (Striped Maple)
  • Acer platanoides L. (Norway maple)
  • Acer pseudoplatanus L. (Sycamore Maple)
  • Acer rubrum L. (Red Maple)
  • Acer saccharinum L. (Silver Maple)
  • Acer saccharum Marshall (Sugar Maple)
  • Acer spicatum Lamarck (Mountain Maple)
  • Acetosa acetosella (L.) P. Miller (Sheep Sorrel)
  • Acetosa hastatula (Baldwin) . Lve (Heart-wing Sorrel)
  • Achillea borealis Bongard (Common Yarrow)
  • Achyranthes japonica (Miq.) Nakai var. hachijoensis Honda (Japanese Chaff Flower)
  • Acmispon helleri (Britt.) A.A. Heller (Carolina Prairie-trefoil)
  • Aconitum reclinatum Gray (White Monkshood)
  • Aconitum uncinatum L. (Blue Monkshood)
  • Acorus calamus L. (Sweetflag, European Calamus)
  • Acorus gramineus Sol. ex Aiton (Grass-leaf Sweetflag, Japanese Sweetflag)
  • Acrobolbus ciliatus (Mitt.) Schiffn.
  • Actaea pachypoda Ell. (White Baneberry, Dolls'-eyes)
  • Actaea podocarpa DC. (Mountain Black Cohosh, Late Black Cohosh)
  • Actaea racemosa L. (Common Black Cohosh, Bugbane)
  • Actaea rubifolia (Kearney) Kartesz (Appalachian Black Cohosh)
  • Actinidia chinensis Planch. (Kiwi)
  • Adiantum capillus-veneris L. (Southern Maidenhair Fern, Venus'-hair Fern)
  • Adiantum pedatum L. (Northern Maidenhair Fern)
  • Adlumia fungosa (Ait.) Greene ex BSP (Climbing Fumitory, Alleghany Vine)
  • Aegilops cylindrica Host (Jointed Goatgrass)
  • Aegilops neglecta Req. ex Bertoloni (Small Goat Grass, Three-awned Goat Grass)
  • Aegopodium podagraria L. (Bishop's Goutweed)
  • Aeschynomene indica L. (Southern Joint-vetch, Indian Joint-vetch)
  • Aeschynomene virginica (L.) B.S.P. (Sensitive Joint-vetch, Northern Joint-vetch)
  • Aesculus flava Solander (Yellow Buckeye)
  • Aesculus pavia L. var. pavia (Red Buckeye)
  • Aesculus sylvatica Bartr. (Painted Buckeye)
  • Agalinis auriculata (Michx.) Blake (Earleaf False Foxglove)
  • Agalinis decemloba (Greene) Pennell (Ten-lobed False Foxglove)
  • Agalinis fasciculata (Ell.) Raf. (Tall False Foxglove, Fascicled False Foxglove)
  • Agalinis maritima (Raf.) Raf. var. maritima (Salt Marsh False Foxglove)
  • Agalinis obtusifolia Raf. (Bluntleaf False Foxglove)
  • Agalinis purpurea (L.) Pennell (Purple False Foxglove)
  • Agalinis setacea (J.F. Gmel.) Raf. (Threadleaf False Foxglove)
  • Agalinis tenuifolia (Vahl) Raf. (Slender-leaf False Foxglove, Slender False Foxglove)
  • Agalinis virgata Raf. (Pine-barren False Foxglove)
  • Agastache nepetoides (L.) Kuntze (Yellow Giant Hyssop)
  • Agastache rugosa (Fisch. & C.A. Meyer) Kuntze (Korean Mint, Purple Giant Hyssop)
  • Agastache scrophulariifolia (Willd.) Kuntze (Purple Giant Hyssop)
  • Ageratina altissima (L.) King & H.E. Robins. (White Snakeroot)
  • Ageratina aromatica (L.) Spach (Small White Snakeroot, Lesser Snakeroot)
  • Ageratina roanensis (Small) E.E. Lamont (Appalachian White Snakeroot)
  • Agrimonia gryposepala Wallr. (Tall Hairy Agrimony)
  • Agrimonia microcarpa Wallr. (Low Agrimony)
  • Agrimonia parviflora Ait. (Small-flowered Agrimony, Harvest-lice)
  • Agrimonia pubescens Wallr. (Downy Agrimony)
  • Agrimonia rostellata Wallr. (Woodland Agrimony)
  • Agrostemma githago L. var. githago (Common Corncockle)
  • Agrostis altissima (Walt.) Tuckerm. (Coastal Bog Bentgrass, Tall Bentgrass)
  • Agrostis capillaris L. (Colonial Bentgrass)
  • Agrostis elliottiana J.A. Schultes (Elliott's Bentgrass, Southern Bentgrass)
  • Agrostis gigantea Roth (Redtop)
  • Agrostis hyemalis (Walt.) B.S.P. (Winter Bentgrass, Ticklegrass)
  • Agrostis perennans (Walt.) Tuckerman (Autumn Bentgrass)
  • Agrostis scabra Willd. (Rough Bentgrass)
  • Agrostis stolonifera L. (Creeping Bentgrass)
  • Ailanthus altissima (P. Miller) Swingle (Tree-of-heaven)
  • Aira caryophyllea L. (Silver Hairgrass)
  • Aira elegans Willd. ex Kunth (Elegant Hairgrass)
  • Aira praecox L. (Early Hairgrass, Spike Hairgrass)
  • Ajuga chamaepitys (L.) Schreb. (Yellow Bugle, Ground-pine Bugle)
  • Ajuga reptans L. (Carpet-bugle)
  • Akebia quinata (Houtt.) Dcne. (Five-leaf Akebia, Chocolate Vine)
  • Albizia julibrissin Durazz. (Mimosa, Silk Tree)
  • Alcea rosea L. (Hollyhock)
  • Aldrovanda vesiculosa L. (Waterwheel Plant)
  • Aletris aurea Walt. (Golden Colicroot)
  • Aletris farinosa L. (White Colicroot)
  • Alisma gramineum Lej. (Grass-leaved Water Plantain)
  • Alisma subcordatum Rafinesque (Southern Water-plantain)
  • Alliaria petiolata (Bieberstein) Cavara & Grande (Garlic Mustard, Hedge Garlic)
  • Allium allegheniense Small (Allegheny Onion)
  • Allium ampeloprasum L. (Wild Leek)
  • Allium canadense L. var. canadense (Wild Onion, Meadow Onion)
  • Allium cernuum Roth (Nodding Onion)
  • Allium oxyphilum Wherry (Shale Barren Nodding Onion)
  • Allium tricoccum Ait. (Ramps, Wild Leek, Rampscallions)
  • Allium vineale L. (Field Garlic, Onion Grass, Wild Onion)
  • Alnus glutinosa (L.) Gaertn. (Black Alder, European Alder)
  • Alnus incana (L.) Moench ssp. rugosa (Du Roi) Clausen (Speckled Alder)
  • Alnus serrulata (Ait.) Willd. (Smooth Alder, Hazel Alder)
  • Alopecurus aequalis Sobol. var. aequalis (Short-awn Foxtail Grass)
  • Alopecurus carolinianus Walt. (Carolina Foxtail Grass)
  • Alopecurus geniculatus L. (Water Foxtail Grass)
  • Alopecurus myosuroides Huds. (Slender Foxtail Grass)
  • Alopecurus pratensis L. (Meadow Foxtail Grass)
  • Alternanthera philoxeroides (Mart.) Griseb. (Alligator-weed)
  • Alternanthera pungens Kunth (Mat Chaff Flower, Khakiweed)
  • Althaea officinalis L. (Common Marsh-mallow)
  • Alysicarpus vaginalis (L.) DC. (Alyce Clover)
  • Alyssum alyssoides (L.) L. (Pale Alyssum, Yellow Alyssum)
  • Amaranthus albus L. (Tumbleweed Amaranth, White Amaranth, Prostrate Pigweed)
  • Amaranthus arenicola I.M. Johnston (Sand Amaranth)
  • Amaranthus australis (Gray) Sauer (Southern Water Hemp)
  • Amaranthus blitum L. ssp. emarginatus (Uline & W.L.Bray) Carr., Muoz Garm., & Pedrol (Purple Amaranth, Livid Amaranth)
  • Amaranthus cannabinus (L.) J.D. Sauer (Tidal-marsh Amaranth, Water-hemp)
  • Amaranthus cruentus L. (Red Amaranth, Blood Amaranth, Purple Amaranth)
  • Amaranthus deflexus L. (Large-fruited Amaranth, Argentine Amaranth)
  • Amaranthus hybridus L. (Slender Pigweed, Smooth Pigweed, Green Amaranth)
  • Amaranthus palmeri S. Wats. (Careless-weed, Palmer's Amaranth)
  • Amaranthus powellii S. Wats. (Green Amaranth, Powell's Amaranth)
  • Amaranthus pumilus Rafinesque (Sea-beach Amaranth, Dwarf Amaranth)
  • Amaranthus retroflexus L. (Rough Pigweed, Red-root Amaranth)
  • Amaranthus spinosus L. (Spiny Amaranth)
  • Amaranthus tuberculatus (Moq.) Sauer (Inland water-hemp)
  • Amaranthus viridis L. (Slender Amaranth, Tropical Green Amaranth)
  • Amauropelta noveboracensis (L.) S.E. Fawcett & A.R. Smith (New York Fern)
  • Amblystegium serpens (Hedwig) Schimper
  • Ambrosia artemisiifolia L. (Common Ragweed)
  • Ambrosia bidentata Michx. (Lance-leaf Ragweed)
  • Ambrosia psilostachya DC. (Perennial Ragweed)
  • Ambrosia trifida L. (Giant Ragweed)
  • Amelanchier arborea (Michx. f.) Fernald (Downy Serviceberry)
  • Amelanchier canadensis (L.) Medik. (Canadian Serviceberry)
  • Amelanchier laevis Wieg. (Smooth Serviceberry)
  • Amelanchier nantucketensis Bickn. (Nantucket Serviceberry)
  • Amelanchier obovalis (Michx.) Ashe (Coastal Plain Serviceberry)
  • Amelanchier sanguinea (Pursh) DC. (Roundleaf Serviceberry)
  • Amelanchier spicata (Lam.) K. Koch (Running Serviceberry, Dwarf Serviceberry)
  • Amianthium muscitoxicum (Walt.) Gray (Fly-poison)
  • Ammannia coccinea Rottb. (Scarlet Ammannia, Purple Ammannia)
  • Ammannia latifolia L. (Koehne's Ammannia, Pink Redstem)
  • Amorpha fruticosa L. (False Indigo-bush, Tall Indigo-bush)
  • Ampelopsis cordata Michx. (Heart-leaf Peppervine, False Grape)
  • Ampelopsis glandulosa (Wallr.) Momiy. (Porcelain-berry, Amur Peppervine)
  • Amphiachyris dracunculoides (DC.) Nutt. (Prairie Broomweed)
  • Amphicarpaea bracteata (L.) Fern. var. bracteata (Hog-peanut)
  • Amphicarpaea bracteata (L.) Fern. var. comosa Fassett (American Hog-peanut, Lowland Hog-peanut)
  • Amphicarpum amphicarpon (Pursh) Nash (Pine-barrens Peanut Grass, Pine-Barrens Goobergrass, Blue Maidencane)
  • Amphidium lapponicum (Hedw.) Schimp.
  • Amphidium mougeotii (Bruch & Schimp.) Schimp.
  • Amsonia tabernaemontana Walt. (Eastern Blue-star, Eastern Blue Dogbane)
  • Anacamptodon splachnoides (Froel. ex Brid.) Brid. (Knothole Moss)
  • Anagallis arvensis L. (Scarlet Pimpernel, Common Pimpernel)
  • Anagallis monelli L. (Blue Pimpernel)
  • Anaphalis margaritacea (L.) Benth. & Hook. f. (Pearly Everlasting)
  • Anastrophyllum michauxii (F. Weber) H. Buch ex A. Evans
  • Anchistea virginica (L.) Presl (Virginia Chain Fern)
  • Anchusa arvensis (L.) Bieb. (Small Bugloss)
  • Andersonglossum virginianum (L.) J.I. Cohen (Wild Comfrey)
  • Andreaea rothii F. Weber & D. Mohr (Needle-Leaved Lantern Moss)
  • Andreaea rupestris Hedwig (Broad-Leaved Lantern Moss)
  • Andrographis echioides (L.) Nees (False Water-willow)
  • Andropogon campbellii U.B. Deshmukh, M.B. Shende, & E.S. Reddy (Deceptive Bluestem)
  • Andropogon cretaceus Weakley & Schori (Chalky Bluestem)
  • Andropogon gerardii Vitman (Big Bluestem, Turkeyfoot)
  • Andropogon glomeratus (Walt.) B.S.P. (Bushy Bluestem)
  • Andropogon gyrans Ashe (Elliott's Bluestem)
  • Andropogon hirsutior (Hackel) Weakley & LeBlond (Hairy Bluestem)
  • Andropogon mohrii (Hack.) Hack. ex Vasey (Mohr's Bluestem, Tawny Bluestem)
  • Andropogon perangustatus Nash (Narrow-leaved Bluestem)
  • Andropogon tenuispatheus (Nash) Nash (Maritime Bushy Bluestem)
  • Andropogon ternarius Michx. var. ternarius (Splitbeard Bluestem, Silvery Bluestem)
  • Andropogon virginicus L. var. virginicus (Broomsedge, Broomstraw, Sedge Grass, Sage Grass)
  • Anemonastrum canadense (L.) Mosyakin (Canada Anemone)
  • Anemone berlandieri Pritz. (Eastern Prairie Anemone, Ten-petal Thimbleweed)
  • Anemone blanda Schott & Kotschy (Grecian Windflower)
  • Anemone lancifolia Pursh (Lanceleaf Anemone, Mountain Anemone)
  • Anemone quinquefolia L. var. minima (DC.) Frodin (Dwarf Anemone)
  • Anemone quinquefolia L. var. quinquefolia (Wood Anemone)
  • Anemone virginiana L. var. virginiana (Thimbleweed, Tall Anemone)
  • Anethum graveolens L. (Dill)
  • Aneura pinguis (L.) Dumort. var. pinguis
  • Aneura sharpii Inoue & N.G. Mill.
  • Angelica lucida L. (Seacoast Angelica)
  • Angelica triquinata Michx. (Filmy Angelica, Mountain Angelica)
  • Angelica venenosa (Greenway) Fern. (Hairy Angelica)
  • Anoda cristata (L.) Schlecht. (Crested Anoda, Spurred Anoda)
  • Anomobryum julaceum (Schrad. ex P. Gaertn., B. Mey. & Scherb.) Schimp.
  • Anomodon attenuatus (Hedwig) Huebener
  • Anomodon minor (Hedwig) Lindberg
  • Anomodon rostratus (Hedwig) Schimper
  • Anomodon rugelii (Mll. Hal.) Keissl.
  • Anomodon tristis (Ces.) Sull. & Lesq.
  • Anomodon viticulosus (Hedw.) Hooker & Taylor
  • Antennaria howellii Greene ssp. neodioica (Greene) Bayer (Howell's Pussytoes)
  • Antennaria howellii Greene ssp. petaloidea (Greene) Bayer (Small Pussytoes)
  • Antennaria neglecta Greene (Field Pussytoes)
  • Antennaria parlinii Fern. ssp. fallax (Greene) Bayer & Stebbins (Big-head Pussytoes)
  • Antennaria parlinii Fern. ssp. parlinii (Parlin's Pussytoes)
  • Antennaria plantaginifolia (L.) Richards. (Plantain-leaved Pussytoes)
  • Antennaria solitaria Rydb. (Single-head Pussytoes)
  • Antennaria virginica Stebbins (Shale-barren Pussytoes)
  • Anthemis arvensis L. (Corn Chamomile)
  • Anthemis cotula L. (Mayweed, Stinking Chamomile)
  • Anthemis secundiramea Biv. (Prostrate Chamomile)
  • Anthoxanthum aristatum Boiss. (Annual Vernal Grass)
  • Anthoxanthum odoratum L. (Sweet Vernal Grass)
  • Anthriscus caucalis Bieb. (Bur Chervil, Bur Parsley)
  • Anthriscus cerefolium (L.) Hoffmann (Garden Chervil)
  • Anthriscus sylvestris (L.) Hoffman (Wild Chervil)
  • Anticlea glauca Kunth (White Death-camas, White Camas)
  • Antirrhinum majus L. (Common Snapdragon)
  • Aphanes australis Rydberg (Slender Parsley-piert)
  • Aphanorrhegma serratum (Hook. & Wilson) Sull.
  • Aphyllon uniflorum L. (Cancer-root)
  • Apios americana Medik. (Groundnut)
  • Aplectrum hyemale (Muhl. ex Willd.) Torrey (Puttyroot, Adam-and-Eve)
  • Apocynum androsaemifolium L. (Spreading Dogbane)
  • Apocynum cannabinum L. (Indian Hemp, Hemp Dogbane)
  • Apocynum floribundum Greene (Intermediate Dogbane)
  • Apocynum sibiricum Jacq. (Clasping-leaved Dogbane)
  • Aquilegia canadensis L. (Wild Columbine, Eastern Red Columbine)
  • Arabidopsis lyrata (L.) O'Kane & Al-Shehbaz ssp. lyrata (Lyre-leaf Rock Cress)
  • Arabidopsis thaliana (Linnaeus) Heynhold (Mouse-ear Cress)
  • Arabis adpressipilis (M. Hopkins) Al-Shehbaz (Hairy Rock Cress, Slender Rock Cress)
  • Arabis patens Sullivant (Spreading Rock Cress)
  • Aralia hispida Vent. (Bristly Sarsaparilla)
  • Aralia nudicaulis L. (Wild Sarsaparilla)
  • Aralia racemosa L. (Spikenard, American Spikenard)
  • Aralia spinosa L. (Devil's Walking-stick)
  • Archidium alternifolium (Dicks. & Hedw.) Schimp.
  • Archidium donnellii Austin
  • Archidium ohioense Schimp. ex Mll. Hal.
  • Arctium minus Bernh. (Common Burdock, Lesser Burdock)
  • Arctostaphylos uva-ursi (L.) Spreng. (Bearberry, Kinnikinick)
  • Arenaria lanuginosa (Michx.) Rohrb. var. lanuginosa (Spreading Sandwort)
  • Arenaria leptoclados (Reichenbach) Guss. (Small Thyme-leaved Sandwort, Slender Sandwort)
  • Arenaria serpyllifolia L. (Large Thyme-leaved Sandwort)
  • Arethusa bulbosa L. (Dragon's-mouth, Bog-rose, Arethusa)
  • Argemone mexicana L. (Mexican Prickly-Poppy)
  • Arisaema dracontium (L.) Schott (Green Dragon)
  • Arisaema triphyllum (L.) Schott ssp. pusillum (Peck) Huttleston (Small Jack-in-the-pulpit)
  • Arisaema triphyllum (L.) Schott ssp. stewardsonii (Britt.) Huttleston (Bog Jack-in-the-pulpit)
  • Arisaema triphyllum (L.) Schott ssp. triphyllum (Common Jack-in-the-pulpit)
  • Aristida dichotoma Michx. var. curtissii Gray (Curtiss' Three-awn Grass)
  • Aristida dichotoma Michx. var. dichotoma (Fork-tip Three-awn Grass)
  • Aristida lanosa Muhl. ex Ell. (Woolly Three-awn Grass)
  • Aristida longespica Poir. (Eastern Slim-spike, Long-awned Slim-spike, Three-awn Grass)
  • Aristida oligantha Michx. (Prairie Three-awn Grass)
  • Aristida purpurascens Poir. (Purple Three-awn Grass, Arrow-feather, Three-awn Grass)
  • Aristida ramosissima Engelm. ex A.Gray, (S-Curve Threeawn)
  • Aristida tuberculosa Nutt. (Sea-beach Needlegrass, Seaside Three-awn Grass)
  • Aristida virgata Trin. (Wandlike Three-awn Grass)
  • Arivela viscosa (L.) Raf. (Yellow Cleome)
  • Arnica acaulis (Walt.) B.S.P. (Leopard's-bane)
  • Arnoglossum atriplicifolium (L.) H.E. Robins. (Pale Indian-plantain)
  • Arnoglossum reniforme (Hooker) H. Robinson (Great Indian-plantain)
  • Aronia arbutifolia (L.) Pers. (Red Chokeberry)
  • Aronia melanocarpa (Michx.) Elliott (Black Chokeberry)
  • Aronia prunifolia (Marsh.) Rehder (Purple Chokeberry)
  • Arrhenatherum elatius (L.) J. & K. Presl var. bulbosum (Willd.) Spenner (Tuber Oatgrass)
  • Arrhenatherum elatius (L.) J. & K. Presl var. elatius (Tall Oatgrass)
  • Arrhenopterum heterostichum Hedwig
  • Artemisia abrotanum L. (Southernwood)
  • Artemisia annua L. (Sweet Wormwood, Annual Wormwood, Sweet Annie)
  • Artemisia ludoviciana Nutt. ssp. ludoviciana (Silver Wormword, Western Mugwort, White Sagebrush)
  • Artemisia stelleriana Bess. (Hoary Mugwort, Beach Wormwood)
  • Artemisia vulgaris L. (Common Mugwort)
  • Arthraxon hispidus (Thunb.) Makino var. hispidus (Joint-head Grass)
  • Arum italicum P. Miller (Italian Arum, Orange Candleflower)
  • Aruncus dioicus (Walt.) Fernald var. dioicus (Goat's-beard)
  • Arundinaria gigantea (Walt.) Muhl. (Giant Cane, River Cane)
  • Arundinaria tecta (Walt.) Muhl. (Small Cane, Switch Cane)
  • Arundo donax L. (Giant Reed)
  • Asarum canadense L. (Common Wild Ginger)
  • Asclepias amplexicaulis J.E. Smith (Clasping Milkweed)
  • Asclepias exaltata L. (Tall Milkweed)
  • Asclepias incarnata L. (Swamp Milkweed)
  • Asclepias incarnata L. var. incarnata (Swamp Milkweed)
  • Asclepias incarnata L. var. pulchra (Ehrh. ex Willd.) Pers. (Swamp Milkweed)
  • Asclepias lanceolata Walt. (Few-flower Milkweed)
  • Asclepias longifolia Michx. (Long-leaf Milkweed)
  • Asclepias purpurascens L. (Purple Milkweed)
  • Asclepias quadrifolia Jacq. (Four-leaf Milkweed)
  • Asclepias rubra L. (Red Milkweed)
  • Asclepias syriaca L. (Common Milkweed)
  • Asclepias tuberosa L. var. rolfsii (Britt. ex Vail) Shinners (Sandhills Butterfly-weed)
  • Asclepias tuberosa L. var. tuberosa (Butterfly-weed, Common Butterfly-weed)
  • Asclepias variegata L. (White Milkweed)
  • Asclepias verticillata L. (Whorled Milkweed)
  • Asclepias viridiflora Raf. (Green Milkweed)
  • Asimina parviflora (Michx.) Dunal (Dwarf Pawpaw, Small-flowered Pawpaw, Small-fruited Pawpaw)
  • Asimina triloba (L.) Dunal (Pawpaw, Common Pawpaw)
  • Asparagus officinalis L. (Asparagus)
  • Aspiromitus punctatus (L.) Schljakov
  • Asplenium bradleyi D.C. Eaton (Bradley's Spleenwort)
  • Asplenium montanum Willd. (Mountain Spleenwort)
  • Asplenium pinnatifidum Nuttall (Lobed Spleenwort, Pinnatifid Spleenwort)
  • Asplenium platyneuron (L.) B.S.P. (Ebony Spleenwort)
  • Asplenium resiliens Kunze (Blackstem Spleenwort)
  • Asplenium rhizophyllum L. (Walking Fern)
  • Asplenium ruta-muraria L. var. cryptolepis (Fern.) Wherry (American Wall-rue)
  • Asplenium trichomanes L. ssp. quadrivalens D.E. Meyer (Northern Maidenhair Spleenwort)
  • Asplenium trichomanes L. ssp. trichomanes (Maidenhair Spleenwort)
  • Asplenium ebenoides R.R. Scott (Scott's Spleenwort)
  • Asplenium kentuckiense T.N. McCoy (Kentucky Spleenwort)
  • Asplenium trudellii Wherry (Trudell's Spleenwort)
  • Asplenium virginicum Maxon (Virginia Spleenwort)
  • Asplenium wherryi D.M. Sm. (Wherry's Spleenwort)
  • Aster tataricus L. f. (Tartarian Aster)
  • Asterella tenella (L.) P. Beauv.
  • Astilbe biternata (Vent.) Britt. (Appalachian False Goat's-beard)
  • Astragalus canadensis L. var. canadensis (Canada Milkvetch)
  • Astragalus distortus T. & G. var. distortus (Ozark Milkvetch, Bent Milkvetch)
  • Astragalus neglectus (Torr. & Gray) Sheldon (Cooper's Milkvetch)
  • Athyrium angustum (Willd.) K. Presl (Northern Lady Fern)
  • Athyrium asplenioides (Michx.) A.A. Eaton (Southern Lady Fern)
  • Atrichum altecristatum (Renauld & Cardot) B.B. Smyth & L.C.D. Smyth (Wavy Starburst Moss)
  • Atrichum angustatum (Brid.) Bruch & Schimp. (Slender Starburst Moss)
  • Atrichum crispulum Schimp. ex Besch. (Crispy Starburst Moss)
  • Atrichum crispum (James) Sull. (Oval Starburst Moss)
  • Atrichum cylindricum (F. Weber) G.L. Sm.
  • Atrichum undulatum (Hedw.) P. Beauv.
  • Atriplex dioica Raf. (Thick-leaf Orach)
  • Atriplex glabriuscula Edmondston (Smooth Orach, Maritime Orach, Scotland Saltbush)
  • Atriplex mucronata Raf. (Sea-beach Orach)
  • Atriplex patula L. (Spear Orach)
  • Atriplex prostrata Boucher ex DC. (Halberd-leaf Orach, Thin-leaf Orach, Triangle Orach)
  • Aulacomnium palustre (Hedw.) Schwgr. (Ribbed Bog Moss)
  • Aureolaria flava (L.) Farwell (Smooth Yellow False Foxglove, Smooth Oak-leach)
  • Aureolaria levigata (Raf.) Raf. (Entire-leaf Yellow False Foxglove, Appalachian Oak-leach)
  • Aureolaria pedicularia (L.) Raf. (Fern-leaf Yellow False Foxglove, Annual Oak-leach)
  • Aureolaria virginica (L.) Pennell (Downy Yellow False Foxglove, Downy Oak-leach)
  • Aurinia saxatilis (L.) Desv. ssp. saxatilis (Basket-of-gold, Gold-dust)
  • Avena sativa L. (Oats)
  • Avenella flexuosa (Linnaeus) Drejer (Wavy Hairgrass)
  • Axonopus fissifolius (Raddi) Kuhlm. (Common Carpetgrass, Southern Carpetgrass)
  • Axonopus furcatus (Fluegge) A.S. Hitchc. (Big Carpetgrass)
  • Azolla caroliniana Willd. (Eastern Mosquito Fern, Water Fern)
  • Azolla filiculoides Lam. (Pacific Mosquito Fern, Large Mosquito Fern)
  • Baccharis halimifolia L. (High-tide Bush, Groundsel Tree)
  • Bacopa caroliniana (Walter) B.L. Robinson (Blue Water-hyssop, Carolina Water-hyssop, Lemon Bacopa)
  • Bacopa innominata (G. Maza) Alain (Tropical Water-hyssop)
  • Bacopa monnieri (L.) Wettstein (Coastal Water-hyssop)
  • Bacopa rotundifolia (Michx.) Wettst. (Round-leaf Water-hyssop)
  • Baptisia albescens Small (Narrow-pod White Wild Indigo, Spiked Wild Indigo)
  • Baptisia australis (L.) R. Brown (Blue Wild Indigo)
  • Baptisia cinerea (Raf.) Fern. & Schub. (Gray-hairy Wild Indigo, Carolina Wild Indigo)
  • Baptisia tinctoria (L.) R. Br. ex Ait. f. (Yellow Wild Indigo, Horsefly Weed)
  • Barbarea verna (Miller) Ascherson (Early Winter Cress)
  • Barbarea vulgaris R. Brown (Common Winter Cress, Yellow Rocket)
  • Barbilophozia barbata (Schmidel ex Schreb.) Loeske
  • Barbula convoluta Hedw. var. convoluta
  • Barbula indica (Hook.) Spreng. var. indica
  • Barbula unguiculata Hedwig
  • Bartonia paniculata (Michx.) Muhl. ssp. paniculata (Twining Bartonia, Twining Screwstem)
  • Bartonia verna (Michx.) Raf. ex Bart. (Spring Bartonia, White Screwstem)
  • Bartonia virginica (L.) BSP (Yellow Bartonia, Yellow Screwstem)
  • Bartramia pomiformis Hedwig (Apple Moss)
  • Bassia scoparia (L.) A.J. Scott (Summer-cypress, Burning-bush)
  • Bazzania denudata (Torr. ex Gottsche, Lindenb. & Nees) Trevis.
  • Bazzania nudicaulis A. Evans
  • Bazzania tricrenata (Wahlenb.) Lindb. var. tricrenata
  • Bazzania trilobata (L.) Gray
  • Bellis perennis L. (English Daisy, Lawn Daisy)
  • Benthamidia florida (L.) Spach (Flowering Dogwood)
  • Berberis canadensis P. Mill. (American Barberry, Allegheny Barberry)
  • Berberis julianae Schneider (Wintergreen Barberry, Chinese Barberry)
  • Berberis thunbergii DC (Japanese Barberry)
  • Berchemia scandens (Hill) K.Koch (Supplejack, American Rattan)
  • Berteroa incana (Linnaeus) A. P. DeCandolle (Hoary Alyssum, Hoary False Alyssum)
  • Betula alleghaniensis Britt. (Yellow Birch)
  • Betula lenta L. var. lenta (Sweet Birch, Black Birch)
  • Betula lenta L. var. uber Ashe (Virginia Roundleaf Birch)
  • Betula nigra L. (River Birch, Red Birch)
  • Betula papyrifera Marshall (Paper Birch)
  • Betula pendula Roth (European White Birch)
  • Betula populifolia Marsh. (Gray Birch)
  • Bidens aristosa (Michx.) Britt. (Ozark Tickseed Sunflower)
  • Bidens bipinnata L. (Spanish Needles)
  • Bidens cernua L. (Nodding Beggar-ticks, Nodding Bur-marigold)
  • Bidens comosa (Gray) Wiegand (Three-lobe Beggar-ticks)
  • Bidens comosa (Gray) Wiegand + Bidens connata Muhl. ex Willd. (Three-lobe Beggar-ticks)
  • Bidens connata Muhl. ex Willd. (Purple-stem Beggar-ticks)
  • Bidens discoidea (Torr. & Gray) Britt. (Small Beggar-ticks)
  • Bidens frondosa L. (Devil's Beggar-ticks)
  • Bidens laevis (L.) B.S.P. (Smooth Bur-marigold, Showy Bur-marigold)
  • Bidens mitis (Michx.) Sherff (Coastal Plain Beggar-ticks)
  • Bidens pilosa L. (Hairy Beggar-ticks, Common Beggar-ticks)
  • Bidens polylepis Blake (Midwestern Tickseed Sunflower)
  • Bidens trichosperma (Michx.) Britt. (Tall Swamp Marigold, Crowned Beggar-ticks)
  • Bidens vulgata Greene (Tall Beggar-ticks, Big Devil's Beggar-ticks)
  • Bignonia capreolata L. (Cross-vine)
  • Blasia pusilla Linnaeus
  • Blepharostoma trichophyllum (L.) Dumortier
  • Blephilia ciliata (L.) Benth. (Downy Wood Mint)
  • Blephilia hirsuta (Pursh) Benth. (Hairy Wood Mint)
  • Blindia acuta (Hedwig) Bruch & Schimper (Sharp-leaved Blindia)
  • Boehmeria cylindrica (L.) Sw. (False Nettle)
  • Boerhavia coccinea P. Miller (Wineflower)
  • Bolboschoenus fluviatilis (Torrey) Sojak (River Bulrush)
  • Bolboschoenus novae-angliae (Britton) S.G. Smith (New England Bulrush)
  • Bolboschoenus robustus (Pursh) Sojak (Saltmarsh Bulrush)
  • Boltonia asteroides (L.) L'Her. var. glastifolia (Hill) Fern. (Eastern Doll's-daisy, White Doll's-daisy)
  • Boltonia asteroides (L.) L'Her. var. latisquama (Gray) Cronquist (Midwestern Doll's Daisy)
  • Boltonia caroliniana (Walt.) Fern. (Carolina Doll's-daisy)
  • Boltonia diffusa Ell. var. diffusa (Small-head Doll's-daisy)
  • Boltonia montana J.F. Townsend & V. Karaman-Castro (Valley Doll's-daisy)
  • Borago officinalis L. (Borage)
  • Borodinia burkii (Porter) P.J. Alexander & Windham (Burk's Smooth Rock Cress)
  • Borodinia canadensis (L.) P.J. Alexander & Windham (Sicklepod, Canada Rock Cress)
  • Borodinia dentata (Raf.) P.J. Alexander & Windham (Short's Rock Cress)
  • Borodinia laevigata (Muhl. ex Willd.) P.J. Alexander & Windham (Smooth Rock Cress)
  • Borodinia serotina (Steele) P.J. Alexander & Windham (Shale Barren Rock Cress)
  • Borrichia frutescens (L.) DC. (Seaside Oxeye, Sea Oxeye)
  • Bothriochloa bladhii (Retz.) S.T. Blake (Australian Bluestem, Caucasian Bluestem)
  • Bothriochloa ischaemum (L.) Keng (Yellow Bluestem)
  • Bothriochloa torreyana (Steud.) Scrivanti & Antn (Silver Bluestem)
  • Botrychium angustisegmentum (Pease & A.H. Moore) Fernald (Triangle Grape Fern, Lanceleaf Moonwort)
  • Botrychium matricariifolium (Retz.) A.Braun ex W.D.J.Koch (Daisyleaf Grape Fern, Daisyleaf Moonwort)
  • Botrychium simplex E. Hitchc. var. simplex (Dwarf Grape Fern, Least Moonwort)
  • Botrypus virginianus (L.) Michx. (Rattlesnake Fern)
  • Bouteloua curtipendula (Michx.) Torr. var. curtipendula (Side-oats Grama)
  • Bouteloua dactyloides (Nuttall) J.T. Thomas (Buffalo Grass)
  • Boykinia aconitifolia Nutt. (Brook Saxifrage, Allegheny Brookfoam, Eastern Boykinia)
  • Brachelyma subulatum (P. Beauv.) Cardot
  • Brachyelytrum aristosum (Michx.) Trel. in Banner & Coville (Northern Shorthusk)
  • Brachyelytrum erectum (Schreb. ex Spreng.) Beauv. (Bearded Shorthusk, Common Shorthusk)
  • Brachypodium sylvaticum (Huds.) P. Beauv. ssp. sylvaticum (Slender False Brome)
  • Brachytheciastrum velutinum (Hedw.) Ignatov & Huttunen var. velutinum
  • Brachythecium acuminatum (Hedw.) Austin
  • Brachythecium acutum (Mitt.) Sull.
  • Brachythecium campestre (Mll. Hal.) Schimp.
  • Brachythecium laetum (Brid.) Schimp. (Pleated Foxtail Moss)
  • Brachythecium rivulare Schimper (River Foxtail Moss)
  • Brachythecium rotaeanum de Not.
  • Brachythecium rutabulum (Hedw.) Schimp. (Rough Foxtail Moss)
  • Brachythecium salebrosum (Hoffm. ex F. Weber & D. Mohr) Schimp. (Golden Foxtail Moss)
  • Bradburia pilosa (Nutt.) Semple (Soft Golden-aster)
  • Brasenia schreberi J. F. Gmel. (Water Shield)
  • Brassica juncea (Linnaeus) Czern. (Indian Mustard, Chinese Mustard)
  • Brassica napus Linnaeus (Rutabaga, Rape, Canola)
  • Brassica rapa Linnaeus (Turnip, Bird's Rape, Field Rape, Field Mustard)
  • Braya humilis (C. A. Meyer) Robinson ssp. humilis (Low Braya)
  • Brickellia eupatorioides (L.) Shinners (False Boneset)
  • Briza minor L. (Lesser Quaking Grass)
  • Bromus catharticus Vahl var. catharticus (Rescue Grass)
  • Bromus ciliatus L. (Fringed Brome Grass, Fringed Brome)
  • Bromus erectus Huds. (Upright Brome, Erect Brome)
  • Bromus hordeaceus L. ssp. hordeaceus (Soft Brome Grass, Soft Brome, Soft Chess)
  • Bromus inermis Leyss. (Awnless Brome Grass, Smooth Brome)
  • Bromus japonicus Thunb. ex Murr. (Japanese Brome Grass, Japanese Chess)
  • Bromus kalmii Gray (Arctic Brome, Prairie Brome)
  • Bromus latiglumis (Shear) A.S. Hitchc. (Riverbank Brome, Auricled Brome, Hairy Woodbrome)
  • Bromus nottowayanus Fern. (Nottoway Valley Brome Grass, Satin Brome)
  • Bromus pubescens Sprengel (Common Eastern Brome Grass, Hairy Woodland Brome)
  • Bromus racemosus L. (Smooth Brome, Bald Brome, Meadow Brome, Hairy Chess)
  • Bromus rigidus Roth (Ripgut Grass)
  • Bromus scoparius L. (Broom Brome)
  • Bromus secalinus L. (Cheat, Common Chess, Rye Brome)
  • Bromus sterilis L. (Poverty Brome)
  • Bromus tectorum L. (Downy Brome, Downy Chess, Cheatgrass)
  • Brothera leana (Sull.) Mll. Hal.
  • Brotherella recurvans (Michx.) M. Fleisch. (Satin Moss)
  • Broussonetia papyrifera (L.) L'Her. ex Vent. (Paper Mulberry)
  • Bruchia drummondii Hampe ex E. Britton
  • Bruchia flexuosa (Schwgr.) Mll. Hal
  • Bruchia texana Austin
  • Brunnichia ovata (Walt.) Shinners (Buckwheat-vine, Eardrop-vine, Redvine)
  • Bryhnia graminicolor (Brid.) Grout
  • Bryhnia novae-angliae (Sull. & Lesq.) Grout
  • Bryoandersonia illecebra (Hedw.) H. Rob. (Worm Moss)
  • Bryoerythrophyllum ferruginascens (Stirt.) Giacom.
  • Bryoerythrophyllum recurvirostrum (Hedw.) P. C. Chen
  • Bryum argenteum Hedwig var. argenteum (Silver Moss)
  • Buchnera americana L. (American Bluehearts)
  • Bucklandiella affinis (Schleich. ex F. Weber & D. Mohr) Bednarek-Ochyra & Ochyra
  • Bucklandiella sudetica (Funck) Bednarek-Ochyra & Ochyra
  • Bucklandiella venusta (Frisvoll) Bednarek-Ochyra & Ochyra
  • Buckleya distichophylla (Nutt.) Torr. (Piratebush)
  • Buddleja davidii Franch. (Orange-eye Butterfly-bush)
  • Buglossoides arvensis (L.) I.M. Johnston ssp. arvensis (Corn-gromwell)
  • Bulbostylis barbata (Rottb.) C.B. Clarke (Old World Hairsedge)
  • Bulbostylis capillaris (L.) Kunth ex C.B. Clarke ssp. capillaris (Common Hairsedge)
  • Bulbostylis ciliatifolia (Elliott) Fernald (Savanna Hairsedge)
  • Bulbostylis coarctata (Elliott) Fernald (Elliott's Hairsedge)
  • Bunias erucago Linnaeus (Southern Warty-cabbage)
  • Bunias orientalis Linnaeus (Turkish Rocket)
  • Bupleurum rotundifolium L. (Round-leaf Thoroughwax, Hare's-ear)
  • Bupleurum virgatum Cavanilles (Narrow-leaf Thoroughwax)
  • Burmannia biflora L. (Violet Burmannia)
  • Buxbaumia aphylla Hedwig
  • Buxbaumia minakatae S. Okamura
  • Buxus sempervirens L. (Common Boxwood)
  • Cabomba caroliniana A. Gray (Carolina Fanwort)
  • Cajanus scarabaeoides (L.) Thouars (Showy Pigeonpea)
  • Cakile edentula (Bigelow) Hooker (American Sea Rocket)
  • Cakile maritima Scopoli (European Sea Rocket)
  • Calamagrostis breviligulata (Fern.) Saarela ssp. breviligulata (American Beach Grass)
  • Calamagrostis canadensis (Michx.) Beauv. var. canadensis (Bluejoint, Canada Reedgrass)
  • Calamagrostis porteri Gray ssp. porteri (Porter's Reedgrass)
  • Calamovilfa brevipilis (Torr.) Scribn. (Pine Barren Sandreed, Pine Barren Reedgrass)
  • Calepina irregularis (Asso) Thellung (White Ball Mustard, Calepina)
  • Calibrachoa parviflora (Juss.) D'Arcy (Wild Petunia, Seaside Petunia)
  • Callicarpa americana L. (American Beauty-berry, French-mulberry)
  • Callicarpa dichotoma (Loureiro) K. Koch (Purple Beauty-berry)
  • Callicladium haldanianum (Grev.) H.A. Crum
  • Calliergon cordifolium (Hedw.) Kindb.
  • Calliergonella cuspidata (Hedw.) Loeske
  • Callirhoe involucrata (Torr. & Gray) Gray var. involucrata (Purple Poppy-mallow)
  • Callitriche heterophylla Pursh var. heterophylla (Large Water-starwort)
  • Callitriche palustris L. (Vernal Water-starwort)
  • Callitriche stagnalis Scop. (Pond Water-starwort)
  • Callitriche terrestris Raf. (Terrestrial Water-starwort)
  • Calopogon pallidus Chapman (Pale Grass-pink)
  • Calopogon tuberosus (L.) BSP var. tuberosus (Tuberous Grass-pink, Common Grass-pink)
  • Caltha palustris L. (Marsh Marigold, Cowslip)
  • Calycanthus floridus L. (Sweet-shrub)
  • Calypogeia muelleriana (Schiffn.) Mll. Frib.
  • Calypogeia neesiana (C. Massal. & Carestia) Mll. Frib.
  • Calypogeia neogaea (R.M. Schust.) Bakalin
  • Calypogeia peruviana Nees et Mont.
  • Calypogeia suecica (Arnell & J. Perss.) K. Mller
  • Calypogeia sullivantii Austin
  • Calystegia catesbeiana Pursh (Catesby's False Bindweed)
  • Calystegia pubescens Lindl. (Japanese Bindweed, Hairy False Bindweed)
  • Calystegia sepium (L.) R. Br. complex (Hedge Bindweed)
  • Calystegia sepium (L.) R. Br. ssp. americana (Sims) Brummitt (Northeastern Bindweed)
  • Calystegia sepium (L.) R. Br. ssp. appalachiana (Sims) Brummitt (Appalachian Bindweed)
  • Calystegia sepium (L.) R. Br. ssp. limnophila (Greene) Brummitt (Coastal Plain Bindweed)
  • Calystegia silvatica (Kit.) Griesb. ssp. fraterniflora (Mackenzie & Bush) Brummitt (Large Bindweed, Giant Bindweed)
  • Calystegia soldanella (L.) R. Br. ex Roemer & J. A. Schultes (Seaside Bindweed)
  • Calystegia spithamaea (L.) Pursh ssp. purshiana (Wherry ) Brummitt (Appalachian Low Bindweed)
  • Calystegia spithamaea (L.) Pursh ssp. spithamaea (Low Bindweed)
  • Camassia scilloides (Raf.) Cory (Wild Hyacinth, Quamash Lily, Eastern Camas Lily)
  • Camelina microcarpa Andrzejowski ex. A. P. DeCandolle (Little-seed False Flax, Little-pod False Flax)
  • Camelina sativa (Linnaeus) Crantz (Gold-of-pleasure, False Flax)
  • Campanula divaricata Michx. (Southern Harebell, Appalachian Bellflower)
  • Campanula persicifolia L. (Peachleaf Bellflower)
  • Campanula rapunculoides L. (Creeping Bellflower, Rampion Bellflower)
  • Campanula rotundifolia L. (Harebell, Bluebell Bellflower)
  • Campanulastrum americanum (L.) Small (Tall Bellflower)
  • Campsis radicans (L.) Seem. ex Bureau (Trumpet-creeper)
  • Campyliadelphus chrysophyllus (Brid.) Kanda (Bristle Star Moss)
  • Campylium stellatum (Hedw.) C.E.O. Jensen (Yellow Star Moss)
  • Campylophyllum hispidulum (Brid.) Hedens (Tiny Star Moss)
  • Campylopus carolinae Grout
  • Campylopus surinamensis Mll. Hal.
  • Campylopus tallulensis Sull. & Lesq.
  • Campylostelium saxicola (F. Weber & D. Mohr) Bruch & Schimp.
  • Cannabis sativa L. (Marijuana, Hemp)
  • Capnoides sempervirens (L.) Borkh. (Pale Corydalis, Pink Corydalis, Rock Harlequin)
  • Capsella bursa-pastoris (Linnaeus) Medicus (Common Shepherd's Purse)
  • Cardamine angustata O. E. Schulz (Slender Toothwort)
  • Cardamine bulbosa (Schreber ex. Muhlenberg) Britton, Sterns & Poggenberg (Spring Cress, Bulbous Bittercress)
  • Cardamine clematitis Shuttleworth ex. A. Gray (Mountain Bittercress)
  • Cardamine concatenata (Michaux) O. Schwarz (Cut-leaf Toothwort)
  • Cardamine diphylla (Michaux) A. Wood (Crinkleroot, Two-leaf Toothwort)
  • Cardamine dissecta (Leavenworth) Al-Shehbaz (Fork-leaf Toothwort, Dissected Toothwort)
  • Cardamine douglassii Britton (Purple Cress)
  • Cardamine flagellifera O. E. Schulz (Blue Ridge Bittercress)
  • Cardamine hirsuta Linnaeus (Hairy Bittercress)
  • Cardamine impatiens Linnaeus (Narrow-leaf Bittercress)
  • Cardamine longii Fernald (Long's Bittercress)
  • Cardamine micranthera Rollins (Small-anthered Bittercress)
  • Cardamine occulta Hornem. (Wavy Bittercress)
  • Cardamine parviflora Linnaeus var. arenicola (Britton) O. E. Schulz (Small-flowered Bittercress, Sand Bittercress)
  • Cardamine pensylvanica Muhlenberg ex Willdenow (Pennsylvania Bittercress)
  • Cardamine pratensis L. var. palustris Wimm. & Graebn. (Cuckoo-flower)
  • Cardamine rotundifolia Michaux (American Bittercress, Mountain Watercress)
  • Cardiospermum halicacabum L. (Balloon Vine)
  • Carduus acanthoides L. ssp. acanthoides (Spiny Plumeless Thistle)
  • Carduus crispus L. (Welted Thistle)
  • Carduus nutans L. (Musk Thistle, Nodding Thistle)
  • Carex abscondita Mackenzie (Thicket Sedge)
  • Carex aestivaliformis Mackenzie (Small-fruited Summer Sedge)
  • Carex aestivalis M.A. Curtis ex Gray (Summer Sedge)
  • Carex aggregata Mackenzie (Glomerate Sedge)
  • Carex alata Torrey (Broad-winged Sedge)
  • Carex albicans complex
  • Carex albicans Willd. ex Sprengel var. albicans (White-tinged Sedge)
  • Carex albicans Willd. ex Sprengel var. australis (Bailey) Rettig (Southern White-tinged Sedge)
  • Carex albicans Willd. ex Sprengel var. emmonsii (Dewey ex Torr.) Rettig (Emmons's Sedge)
  • Carex albolutescens Schweinitz (Greenish-white Sedge)
  • Carex albursina Sheldon (White Bear Sedge)
  • Carex amphibola complex
  • Carex amphibola Steudel (Eastern Narrow-leaved Sedge)
  • Carex annectens (Bickn.) Bickn. (Yellow-fruited Sedge)
  • Carex appalachica Webber & Ball (Appalachian Sedge)
  • Carex aquatilis Wahlenb. var. substricta Kukenth. (Aquatic Sedge)
  • Carex arctata Boott (Black Sedge, Drooping Woodland Sedge)
  • Carex arenaria L. (Sand Sedge)
  • Carex argyrantha Tuckerman ex Dewey (Silvery-flowered Sedge, Hay Sedge)
  • Carex arkansana (L.H. Bailey) L.H. Bailey (Arkansas sedge)
  • Carex atherodes Sprengel (Awned Sedge)
  • Carex atlantica Bailey (Prickly Bog Sedge, Atlantic Sedge)
  • Carex aureolensis Steudel (Southern Frank's Sedge)
  • Carex austrina Mackenzie (Southern Sedge)
  • Carex austrodeflexa P.D. McMillan, Sorrie, & van Eerden (Canebrake Sedge)
  • Carex austrolucorum (Rettig) D.P. Poind. & Naczi (Appalachian Woodland Sedge)
  • Carex baileyi Britton (Shortbeak Sedge, Fescue Sedge)
  • Carex barrattii Schw. & Torr. (Barratt's Sedge)
  • Carex blanda Dewey (Eastern Woodland Sedge)
  • Carex brevior (Dewey) Mackenzie ex Lunell (Shortbeak Sedge)
  • Carex bromoides Schk. ex Willd. ssp. bromoides (Common Brome Sedge)
  • Carex bromoides Schk. ex Willd. ssp. montana Naczi (Blue Ridge Brome Sedge)
  • Carex brunnescens (Pers.) Poiret (Brownish Sedge)
  • Carex bullata Schk. ex Willd. var. bullata (Button Sedge)
  • Carex bullata Schk. ex Willd. var. greenei (Boeckeler) Fernald (Greene's Sedge)
  • Carex bushii Mackenzie (Bush's Sedge)
  • Carex buxbaumii Wahlenb. (Brown Bog Sedge, Buxbaum's Sedge)
  • Carex canescens L. var. disjuncta Fernald (Silvery Sedge)
  • Carex careyana Torrey ex Dewey (Carey's Sedge)
  • Carex caroliniana Schweinitz (Carolina Sedge)
  • Carex cephalophora Muhl. ex Willd. (Oval-leaved Sedge)
  • Carex cherokeensis Schweinitz (Cherokee Sedge)
  • Carex collinsii Nuttall (Collins's Sedge)
  • Carex communis Bailey (Fibrous-rooted Sedge)
  • Carex comosa Boott (Bottlebrush Sedge, Bristly Sedge)
  • Carex complanata Torr. & Hook. (Hirsute Sedge)
  • Carex conjuncta Boott (Soft Fox Sedge)
  • Carex conoidea Willd. (Field Sedge)
  • Carex copulata (L.H. Bailey) Mackenzie (Spreading Sedge)
  • Carex corrugata Fernald (Prune-fruited Sedge)
  • Carex crawei Dewey (Crawe's Sedge)
  • Carex crebriflora Wiegand (Coastal Plain Sedge)
  • Carex crinita Lam. (Long-fringed Sedge)
  • Carex crinita Lam. var. brevicrinis Fernald (Short-fringed Sedge)
  • Carex crinita Lam. var. crinita (Long-fringed Sedge)
  • Carex cristatella Britton (Crested Sedge)
  • Carex crus-corvi Shuttw. (Crowfoot Sedge, Ravenfoot Sedge)
  • Carex cumberlandensis Naczi, Kral, & Bryson (Cumberland Sedge)
  • Carex davisii Schw. & Torrey (Davis's Sedge)
  • Carex debilis Michaux var. debilis (White-edged Sedge)
  • Carex debilis Michx. var. pubera A. Gray (Allegheny Sedge)
  • Carex decomposita Muhl. (Cypress-knee Sedge, Epiphytic Sedge)
  • Carex digitalis Willd. (Slender Woodland Sedge)
  • Carex digitalis Willd. var. digitalis (Slender Woodland Sedge)
  • Carex digitalis Willd. var. floridana (Bailey) Naczi & Bryson (Southern Slender Woodland Sedge)
  • Carex digitalis Willd. var. macropoda Fernald (Long-spiked Slender Woodland Sedge)
  • Carex divisa Hudson (Separated Sedge, Divided Sedge)
  • Carex eburnea Boott (Ebony Sedge, Bristle-leaf Sedge)
  • Carex echinata Murray ssp. echinata (Star Sedge, Little Prickly Sedge)
  • Carex emoryi Dewey (Emory's sedge)
  • Carex extensa Goodenough (Long-bracted Sedge)
  • Carex festucacea Schk. ex Willd. (Fescue Sedge)
  • Carex fissa Mackenzie var fissa (Hammock sedge)
  • Carex flaccosperma complex (Meadow Sedge, Thin-fruited Sedge)
  • Carex flaccosperma Dewey (Meadow Sedge, Thin-fruited Sedge)
  • Carex flava L. (Yellow Sedge, Green Sedge)
  • Carex flexuosa Muhl. ex Willd. (Flexuous White-edge Sedge)
  • Carex floridana Schw. (Florida Sedge)
  • Carex folliculata L. (Northern Long Sedge)
  • Carex frankii Kunth (Frank's Sedge)
  • Carex gigantea Rudge (Giant Sedge)
  • Carex glaucescens Elliott (Southern Waxy Sedge)
  • Carex glaucodea Tuckerman ex Olney (Blue Sedge)
  • Carex gracilescens Steudel (Slender Loose-flowered Sedge)
  • Carex gracillima Schw. (Graceful Sedge)
  • Carex granularis Muhl. ex Willd. (Limestone Meadow Sedge)
  • Carex gravida L.H. Bailey (Heavy Sedge)
  • Carex grayi Carey (Gray's Sedge)
  • Carex grisea Wahlenb. (Inflated Narrow-leaved Sedge)
  • Carex gynandra Schweinitz (Nodding sedge)
  • Carex hirsutella Mackenzie (Fuzzy Sedge, Hairy-leaved Sedge)
  • Carex hirta L. (Hairy Sedge, Hammer Sedge)
  • Carex hirtifolia Mackenzie (Pubescent Sedge)
  • Carex hitchcockiana Dewey (Hitchcock's Sedge)
  • Carex hormathodes Fernald (Marsh Straw Sedge)
  • Carex howei Mackenzie (Howe's Sedge)
  • Carex hyalinolepis Steudel (Shoreline Sedge)
  • Carex hystericina Muhl. ex Willd. (Porcupine Sedge)
  • Carex interior Bailey (Inland Sedge)
  • Carex intumescens Rudge var. fernaldii Bailey (Fernald's Bladder Sedge)
  • Carex intumescens Rudge var. intumescens (Bladder Sedge)
  • Carex jamesii Schweinitz (James's Sedge)
  • Carex joorii Bailey (Joor's Sedge, Hummock Sedge, Cypress-swamp Sedge)
  • Carex juniperorum Catling, Rezn., & Crins (Juniper Sedge)
  • Carex kobomugi Ohwi (Japanese Beach Sedge)
  • Carex kraliana Naczi & Bryson (Kral's Sedge)
  • Carex lacustris Willdenow (Lake-shore Sedge)
  • Carex laevivaginata (Kukenth.) Mackenzie (Smooth-sheathed Sedge)
  • Carex lasiocarpa Erhr. var. americana Fernald (Slender Sedge)
  • Carex laxiculmis Schweinitz (Spreading Sedge)
  • Carex laxiflora Lam. (Broad Loose-flowered Sedge)
  • Carex leavenworthii Dewey (Leavenworth's Sedge)
  • Carex leptalea Wahlenberg var. harperi (Fernald) Weatherby & Griscom (Harper's Bristly-stalk Sedge)
  • Carex leptalea Wahlenberg var. leptalea (Bristly-stalk Sedge)
  • Carex leptonervia (Fernald) Fernald (Finely-nerved Sedge, Nerveless Woodland Sedge)
  • Carex lonchocarpa Willd. ex Sprengel (Southern Long Sedge)
  • Carex longii Mackenzie (Long's Sedge)
  • Carex louisianica Bailey (Louisiana Sedge)
  • Carex lupuliformis Sartwell ex Dewey (False Hop Sedge)
  • Carex lupulina Willd. (Hop Sedge)
  • Carex lurida Wahlenb. (Sallow Sedge)
  • Carex manhartii Bryson (Blue Ridge Purple Sedge, Manhart's Sedge)
  • Carex meadii Dewey (Mead's Sedge)
  • Carex mesochorea Mackenzie (Midland Sedge)
  • Carex mitchelliana M.A. Curtis (Mitchell's Sedge)
  • Carex molesta Mackenzie ex Bright (Troublesome Sedge)
  • Carex molestiformis Rezn. & P. Rothr. (Frightful Sedge)
  • Carex muehlenbergii Schk. ex Willd. (Muehlenberg's Sedge)
  • Carex muehlenbergii Schk. ex Willd. var. enervis Boott (Small-fruited Muehlenberg's Sedge)
  • Carex muehlenbergii Schk. ex Willd. var. muehlenbergii (Muehlenberg's Sedge)
  • Carex nigromarginata Schweinitz (Black-edged Sedge)
  • Carex normalis Mackenzie (Greater Straw Sedge)
  • Carex oklahomensis Mackenzie (Oklahoma Sedge)
  • Carex oligocarpa Willd. (Eastern Few-fruited Sedge)
  • Carex opaca (F.J. Hermann) P. Rothrock & Reznicek (Bicknell's sedge)
  • Carex ormostachya Wiegand (Necklace Spike Sedge)
  • Carex oxylepis Torrey & Hooker (Sharp-scale Sedge)
  • Carex pallescens L. (Pale Sedge)
  • Carex pedunculata Muhl. ex Willd. var. pedunculata (Long-stalk Sedge)
  • Carex pellita Willd. (Woolly Sedge)
  • Carex pendula Hudson (Drooping Sedge, Hanging Sedge)
  • Carex pensylvanica Lam. (Pennsylvania Sedge)
  • Carex pigra Naczi (Lazy Sedge)
  • Carex planispicata Naczi (Flat-spiked Sedge)
  • Carex plantaginea Lam. (Plantain-leaved Sedge)
  • Carex platyphylla Carey (Broad-leaved Sedge)
  • Carex polymorpha Muhl. (Variable Sedge)
  • Carex praegracilis Boott (Clustered Field Sedge)
  • Carex prairea Dewey ex Wood (Prairie Sedge)
  • Carex prasina Wahlenb. (Drooping Sedge)
  • Carex projecta Mackenzie (Necklace Sedge)
  • Carex purpurifera Mackenzie (Limestone Purple Sedge)
  • Carex radiata (Wahlenb.) Small (Eastern Star Sedge)
  • Carex reniformis (Bailey) Small (Kidney Sedge)
  • Carex retroflexa Muhl. ex Willd. (Reflexed Sedge)
  • Carex reznicekii Werier (Reznicek's Sedge)
  • Carex roanensis F.J. Hermann (Roan Mountain Sedge)
  • Carex rosea Schk. ex Willd. (Rosy Sedge)
  • Carex rugosperma Mackenzie (Parachute Sedge)
  • Carex ruthii Mackenzie in Britton (Ruth's Sedge)
  • Carex scabrata Schweinitz (Eastern Rough Sedge)
  • Carex schweinitzii Dewey ex Schweinitz (Schweinitz's Sedge)
  • Carex scoparia Schk. ex Willd. (Broom Sedge)
  • Carex seorsa Howe in Gordinier & Howe (Weak Stellate Sedge)
  • Carex shortiana Dewey (Short's Sedge)
  • Carex silicea Olney (Sea-beach Sedge)
  • Carex sparganioides Muhl. ex Willd. (Bur-reed Sedge)
  • Carex spicata Hudson (Prickly Sedge)
  • Carex squarrosa L. (Squarrose Sedge)
  • Carex sterilis Willd. (Sterile Sedge)
  • Carex stipata Muhl. ex Willd. var. maxima Chapman ex Boott (Large Stalk-grain Sedge)
  • Carex stipata Muhl. ex Willd. var. stipata (Stalk-grain Sedge, Awl-fruit Sedge)
  • Carex straminea Willd. in Schk. (Straw Sedge)
  • Carex striata Michaux (Walter's Sedge)
  • Carex striatula Michaux (Lined Sedge)
  • Carex stricta Lam. (Tussock Sedge, Upright Sedge, Stool Sedge)
  • Carex styloflexa Buckley (Bent Sedge)
  • Carex suberecta (Olney) Britton (Prairie Straw Sedge)
  • Carex superata Naczi, Rezn., & Ford (Limestone Forest Sedge)
  • Carex swanii (Fernald) Mackenzie (Swan's Sedge)
  • Carex tetanica Schkuhr (Rigid Sedge)
  • Carex texensis (Torr.) Bailey (Texas Sedge)
  • Carex tonsa (Fernald) Bicknell (Shaved Sedge)
  • Carex torta Boott (Twisted Sedge)
  • Carex tribuloides Wahlenb. var. sangamonensis Clokey (Midwestern Blunt Broom Sedge)
  • Carex tribuloides Wahlenb. var. tribuloides (Blunt Broom Sedge)
  • Carex trichocarpa Willd. (Hairy-fruited Sedge)
  • Carex trisperma Dewey (Three-seeded Sedge)
  • Carex typhina Michaux (Cattail Sedge)
  • Carex umbellata Schk. ex Willd. (Parasol Sedge)
  • Carex utriculata Boott (Beaked Sedge)
  • Carex venusta Dewey var. minor Bckler (Southern Dark Green Sedge)
  • Carex venusta Dewey var. venusta (Dark Green Sedge)
  • Carex vesicaria L. (Inflated Sedge)
  • Carex vestita Willd. (Velvet Sedge)
  • Carex virescens Muhl. ex Willd. (Ribbed Sedge)
  • Carex vulpinoidea Michaux (Fox Sedge)
  • Carex willdenowii Schk. ex Willd. (Willdenow's Sedge)
  • Carex woodii Dewey (Wood's Sedge)
  • Carphephorus bellidifolius (Michx.) Torr. & Gray (Sandy-woods Chaffhead, Sandhill Chaffhead)
  • Carphephorus tomentosus (Michx.) Torr. & Gray (Woolly Chaffhead)
  • Carpinus caroliniana Walt. (American Hornbeam, Ironwood)
  • Cartrema americanum (L.) Nesom (Devilwood, Wild Olive)
  • Carum carvi L. (Caraway)
  • Carya aquatica (Michx.f.) Nutt. (Water Hickory, Bitter Pecan)
  • Carya carolinae-septentrionalis (Ashe) Engl. & Graebn. (Southern Shagbark Hickory, Carolina Shagbark Hickory)
  • Carya cordiformis (Wangenh.) K. Koch (Bitternut Hickory)
  • Carya glabra (P. Miller) Sweet (Pignut Hickory)
  • Carya illinoinensis (Wangenh.) K. Koch (Pecan)
  • Carya ovalis (Wangenh.) Sarg. (Red Hickory, Sweet Pignut Hickory)
  • Carya ovata (P.Mill.) K. Koch (Shagbark hickory)
  • Carya pallida (Ashe) Engl. & Graebn. (Sand Hickory, Pale Hickory)
  • Carya tomentosa (Poir.) Nutt. (Mockernut Hickory)
  • Castanea dentata (Marshall) Borkhausen (American Chestnut)
  • Castanea mollissima Blume (Chinese Chestnut)
  • Castanea pumila (Linnaeus) P. Miller (Allegheny Chinkapin)
  • Castilleja coccinea (L.) Spreng. (Eastern Indian Paintbrush)
  • Catalpa bignonioides Walt. (Southern Catalpa)
  • Catalpa speciosa (Warder) Warder ex Engelm. (Northern Catalpa)
  • Caulophyllum giganteum (Farw.) Loconte & Blackwell (Northern Blue Cohosh)
  • Caulophyllum thalictroides (L.) Michx. (Blue Cohosh, Common Blue Cohosh)
  • Causonis japonica (Thunb.) Raf. (Bush-killer, Sorrel Vine)
  • Ceanothus americanus L. (New Jersey Tea, Redroot)
  • Celastrus orbiculatus Thunb. (Oriental Bittersweet)
  • Celastrus scandens L. (Climbing Bittersweet, American Bittersweet)
  • Celosia argentea L. (Plumed Cockscomb)
  • Celtis laevigata Willd. (Sugarberry, Southern Hackberry)
  • Celtis occidentalis L. (Common Hackberry, Northern Hackberry)
  • Celtis pumila Pursh (Dwarf Hackberry, Georgia Hackberry)
  • Cenchrus americanus (L.) Morrone (Pearl Millet)
  • Cenchrus longispinus (Hack.) Fern. (Northern Sandbur, Common Sandbur)
  • Cenchrus purpurascens Thunb. (Fountain Grass)
  • Cenchrus spinifex Cav. (Coastal Sandbur)
  • Cenchrus tribuloides L. (Dune Sandbur)
  • Centaurea benedicta (L.) L. (Blessed Thistle, Holy Thistle)
  • Centaurea calcitrapa L. (Purple Star-thistle)
  • Centaurea jacea L. (Brown Knapweed)
  • Centaurea nigra L. (Black Knapweed)
  • Centaurea nigrescens Willd. (Tyrol Knapweed)
  • Centaurea solstitialis L. (Yellow Star-thistle)
  • Centaurea stoebe L. ssp. micranthos (S.G. Gmelin ex Gugler) Hayek (Spotted Knapweed)
  • Centaurea moncktonii C.E. Britton (Meadow Knapweed)
  • Centaurium erythraea Raf. (Common Centaury, Forking Centaury)
  • Centaurium pulchellum (Sw.) Druce (Lesser Centaury, Branching Centaury)
  • Centella erecta (L. f.) Fern. (Coinleaf, Erect Centella)
  • Centrosema virginianum (L.) Benth. ssp. virginianum (Spurred Butterfly Pea)
  • Centunculus minimus L. (Chaffweed)
  • Cephalanthus occidentalis L. (Buttonbush)
  • Cephalotaxus harringtonia (J. Knight ex Forbes) Koch (Japanese Plum Yew)
  • Cephalozia bicuspidata (L.) Dumort.
  • Cephaloziella divaricata (Sm.) Schiffn.
  • Cephaloziella divaricata (Sm.) Schiffn. var scabra (Howe) Haynes
  • Cephaloziella hampeana (Nees) Schiffn. ex Loeske
  • Cephaloziella rubella (Nees) Warnst.
  • Cephaloziella spinicaulis Doulin
  • Cerastium arvense L. ssp. strictum Gaudin (Field Chickweed)
  • Cerastium brachypetalum Pers. (Gray Mouse-ear Chickweed)
  • Cerastium brachypodum (Engelm. ex Gray) B.L. Robinson (Shortstalk Chickweed)
  • Cerastium dubium (Bast.) Guepin (Anomalous Mouse-ear Chickweed)
  • Cerastium fontanum Baumg. ssp. vulgare (Hartman) Greuter & Burdet (Common Mouse-ear Chickweed)
  • Cerastium glomeratum Thuill. (Sticky Mouse-ear Chickweed)
  • Cerastium nutans Raf. (Nodding Mouse-ear Chickweed)
  • Cerastium pumilum W. Curtis (Dwarf Mouse-ear)
  • Cerastium semidecandrum L. (Little Mouse-ear Chickweed)
  • Cerastium tomentosum L. (Snow-in-summer)
  • Cerastium velutinum Raf. var. velutinum (Field Chickweed)
  • Ceratodon purpureus (Hedw.) Brid. ssp. purpureus (Purple Moss)
  • Ceratophyllum demersum L. (Common Hornwort, Coontail)
  • Ceratophyllum echinatum A. Gray (Spineless Hornwort)
  • Cercis canadensis L. var. canadensis (Eastern Redbud)
  • Chaenomeles japonica (Thunb.) Lindl. (Japanese Flowering Quince)
  • Chaenomeles speciosa (Sweet) Nakai (Flowering Quince)
  • Chaenorhinum minus (L.) Lange ssp. minus (Dwarf Snapdragon, Lesser Toadflax)
  • Chaerophyllum procumbens (L.) Crantz var. procumbens (Spreading Chervil)
  • Chaerophyllum procumbens (L.) Crantz var. shortii Torr. & Gray (Short's Spreading Chervil)
  • Chaerophyllum tainturieri Hook. (Hairy-fruit Chervil, Southern Wild Chervil)
  • Chaiturus marrubiastrum (L.) Reichenb. (Horehound Motherwort, False Motherwort)
  • Chamaecrista fasciculata (Michx.) Greene var. fasciculata (Common Partridge-pea)
  • Chamaecrista fasciculata (Michx.) Greene var. macrosperma (Fernald) C. F. Reed (Marsh Patridge-pea, Marsh Senna)
  • Chamaecrista nictitans (L.) Moench var. nictitans (Wild Sensitive Plant, Sensitive Partridge-pea)
  • Chamaecyparis thyoides (L.) BSP (Atlantic White Cedar)
  • Chamaelirium luteum (L.) Gray (Devil's-bit)
  • Chamaenerion angustifolium (Linnaeus) Scopoli ssp. circumvagum (Mosquin) Moldenke (Fireweed, Great Willow-herb)
  • Chamaepericlymenum canadense (L.) Ascherson & Graebner (Bunchberry, Dwarf Cornel, Dwarf Dogwood)
  • Chasmanthium latifolium (Michx.) Yates (River Oats)
  • Chasmanthium laxum (L.) Yates (Slender Spikegrass)
  • Chasmanthium sessiliflorum (Poir.) Yates (Long-leaf Spikegrass)
  • Cheilolejeunea clypeata (Schwein.) W. Ye & R. L. Zhu
  • Cheilolejeunea conchifolia (A. Evans) W. Ye & R.L. Zhu
  • Cheilolejeunea unciloba (Lindenb.) Malombe
  • Chelidonium majus L. (Greater Celandine)
  • Chelone cuthbertii Small (Cuthbert's Turtlehead)
  • Chelone glabra L. (White Turtlehead)
  • Chelone obliqua L. var. obliqua (Red Turtlehead)
  • Chenopodiastrum murale (Linnaeus) S. Fuentes, Uotila, & Borsch (Nettleleaf Goosefoot)
  • Chenopodiastrum simplex (Torrey) S. Fuentes, Uotila, & Borsch (Maple-leaf Goosefoot, Giant-seed Goosefoot)
  • Chenopodium album L. (Lamb's-quarters, Pigweed)
  • Chenopodium berlandieri Moq. (Pit-seed Goosefoot)
  • Chenopodium berlandieri Moquin-Tandon var. macrocalycium (Aellen) Cronquist (Pit-seed Goosefoot)
  • Chenopodium foggii Wahl (Fogg's Goosefoot)
  • Chenopodium opulifolium Schrad. (Gray Goosefoot)
  • Chenopodium pratericola Rydberg (Narrowleaf Goosefoot)
  • Chenopodium standleyanum Aellen (Woodland Goosefoot, Standley's Goosefoot)
  • Chiloscyphus bicuspidatus (Steph.) J.J. Engel & R.M. Schust.
  • Chiloscyphus pallescens (Ehrh. ex Hoffm.) Dumort. var. fragilis (Roth) Muell. Frib. ex R.M. Schust.
  • Chiloscyphus pallescens (Ehrh. ex Hoffm.) Dumort. var. pallescens
  • Chiloscyphus polyanthos (L.) Corda var. polyanthos
  • Chiloscyphus polyanthos (L.) Corda var. rivularis (Schrad.) Nees
  • Chimaphila maculata (L.) Pursh (Spotted Wintergreen, Striped Wintergreen)
  • Chimaphila umbellata (L.) W. Barton ssp. cisatlantica (Blake) Hulten (Pipsissewa, Prince's-pine)
  • Chionanthus virginicus L. (Fringetree, Old Man's Beard)
  • Chloris verticillata Nutt. (Windmill Grass)
  • Chloris virgata Sw. (Feather Finger Grass, Showy Chloris)
  • Chondrilla juncea L. (Skeleton-weed, Rush Skeleton-weed)
  • Chrysogonum repens (Cassini) Nesom (Carolina Green-and-gold)
  • Chrysogonum virginianum L. (Green-and-gold)
  • Chrysopsis gossypina (Michx.) Ell. (Cottony Golden-aster)
  • Chrysopsis mariana (L.) Ell. (Maryland Golden-aster)
  • Chrysosplenium americanum Schwein. ex Hook. (Golden Saxifrage, Water-mat, Water-carpet)
  • Cichorium intybus L. (Chicory, Succory)
  • Cicuta bulbifera L. (Bulb-bearing Water-hemlock, Bulblet-bearing Water-hemlock)
  • Cicuta maculata L. var. curtisii (Coult. & Rose) Fern. (Southern Water-hemlock)
  • Cicuta maculata L. var. maculata (Water-hemlock, Spotted Water-hemlock)
  • Cinna arundinacea L. (Common Wood Reedgrass, Sweet Wood Reed-grass)
  • Cinna latifolia (Trev. ex Goepp.) Griseb. (Slender Wood Reedgrass, Drooping Wood Reedgrass)
  • Circaea alpina L. ssp. alpina (Small Enchanter's Nightshade)
  • Circaea canadensis (L.) Hill (Enchanter's Night-shade)
  • Cirriphyllum piliferum (Hedw.) Grout
  • Cirsium altissimum (L.) Hill (Tall Thistle)
  • Cirsium arvense (L.) Scop. (Canada Thistle, Field Thistle)
  • Cirsium carolinianum (Walt.) Fern. & Schub. (Carolina Thistle)
  • Cirsium discolor (Muhl. ex Willd.) Spreng. (Field Thistle)
  • Cirsium horridulum Michx. var. horridulum (Yellow Thistle, Common Yellow Thistle)
  • Cirsium muticum Michx. (Swamp Thistle)
  • Cirsium nuttallii DC. (Nuttall's Thistle)
  • Cirsium pumilum (Nutt.) Spreng. (Pasture Thistle)
  • Cirsium repandum Michx. (Sandhill Thistle, Coastal Plain Thistle)
  • Cirsium virginianum (L.) Michx. (Virginia Thistle)
  • Cirsium vulgare (Savi) Ten. (Bull Thistle)
  • Citrullus lanatus (Thunb.) Matsumura & Nakai (Watermelon)
  • Citrus trifoliata L. (Hardy Orange, Trifoliate Orange)
  • Cladium jamaicense Crantz (Sawgrass)
  • Cladium mariscoides (Muhl.) Torrey (Twig-rush)
  • Clasmatodon parvulus (Hampe) Sull.
  • Claytonia caroliniana Michx. (Carolina Spring Beauty, Broad-leaved Spring Beauty)
  • Claytonia rubra (T.J. Howell) Tidestrom ssp. rubra (Red-stem Spring Beauty)
  • Claytonia virginica L. var. virginica (Spring Beauty, Virginia Spring Beauty, Eastern Spring Beauty)
  • Claytosmunda claytoniana (L.) Metzgar & Rouhan (Interrupted Fern)
  • Cleistesiopsis bifaria (Fernald) Pansarin & F. Barros (Appalachian Small Spreading Pogonia)
  • Cleistesiopsis divaricata (L.) Pansarin & F. Barros (Large Spreading Pogonia)
  • Cleistesiopsis oricamporum P.M. Brown (Coastal Plain Small Spreading Pogonia)
  • Clematis addisonii Britt. (Addison's Leatherflower)
  • Clematis albicoma Wherry (White-haired Leatherflower)
  • Clematis catesbyana Pursh (Satin-curls)
  • Clematis coactilis (Fern.) Keener (Virginia White-haired Leatherflower)
  • Clematis crispa L. (Marsh Swamp Leatherflower, Marsh Clematis, Blue Jasmine)
  • Clematis glaucophylla Small (White-leaved Leatherflower)
  • Clematis occidentalis (Hornemann) DC. var. occidentalis (Purple Clematis, Mountain Clematis)
  • Clematis ochroleuca Ait. (Curlyheads)
  • Clematis terniflora DC. (Sweet Autumn Clematis, Japanese Clematis)
  • Clematis viorna L. (Northern Leatherflower, Vase-vine)
  • Clematis virginiana L. (Virgin’s-bower)
  • Clematis viticaulis Steele (Millboro Leatherflower)
  • Clerodendrum trichotomum Thunb. (Harlequin Glory-Bower, Peanut Butter Tree)
  • Clethra acuminata Michx. (Mountain Pepperbush, Mountain White-alder)
  • Clethra alnifolia L. (Sweet Pepperbush, Coastal White-alder)
  • Climacium americanum Bridel (Common Tree Moss)
  • Climacium dendroides (Hedw.) F. Weber & D. Mohr (Palm Tree Moss)
  • Clinopodium acinos (L.) Kuntze (Basil Thyme)
  • Clinopodium arkansanum (Nutt.) House (Limestone Calamint)
  • Clinopodium ascendens (Jordan) Sampaio (Common Calamint)
  • Clinopodium calamintha (L.) Stace (Lesser Calamint, Basil-thyme)
  • Clinopodium gracile (Benth.) Kuntze (Slender Wild Basil)
  • Clinopodium vulgare L. (Wild Basil)
  • Clintonia borealis (Ait.) Raf. (Bluebead Lily, Yellow Clintonia)
  • Clintonia umbellulata (Michx.) Morong (Speckled Wood Lily, White Clintonia)
  • Clitoria mariana L. var. mariana (Butterfly Pea)
  • Cnidoscolus stimulosus (Michx.) Engelm. & Gray (Spurge-nettle, Tread Softly, Finger Rot, Bull-nettle)
  • Codriophorus acicularis (Hedw.) P. Beauv.
  • Codriophorus aduncoides (Bednarek-Ochyra) Bednarek-Ochyra & Ochyra
  • Coincya monensis (L.) Greuter & Burdet ssp. recurvata (Allioni) Leadlay (Wallflower-cabbage)
  • Coleataenia anceps (Michx.) Soreng ssp. anceps (Beaked Panic Grass)
  • Coleataenia anceps (Michx.) Soreng ssp. rhizomatosa (Hitchcock & Chase) Soreng (Small Beaked Panic Grass)
  • Coleataenia longifolia (Torrey) Soreng ssp. combsii (Scribner & C.R. Ball) Soreng (Combs' Panic Grass)
  • Coleataenia longifolia (Torrey) Soreng ssp. longifolia (Long-leaved Panic Grass)
  • Coleataenia pulchra (F. Dietrich) Mabberley & LeBlond (Redtop Panic Grass)
  • Coleataenia rigidula (Bosc ex Nees) LeBlond ssp. condensa (Nash) LeBlond (Dense Panic Grass)
  • Coleataenia rigidula (Bosc ex Nees) LeBlond ssp. rigidula (Tall Flat Panic Grass)
  • Collinsia verna Nutt. (Eastern Blue-eyed Mary)
  • Collinsonia canadensis L. (Richweed, Canada Horsebalm)
  • Collinsonia verticillata Baldw. (Whorled Horsebalm)
  • Cololejeunea biddlecomiae (Austin ex Pearson) A. Evans
  • Cololejeunea cardiocarpa (Mont.) A. Evans
  • Comandra umbellata (L.) Nuttall var. umbellata (Eastern Bastard Toadflax)
  • Commelina benghalensis L. (Benghal dayflower; Tropical spiderwort)
  • Commelina communis L. (Asiatic Dayflower, Common Dayflower)
  • Commelina diffusa Burman f. (Creeping Dayflower)
  • Commelina erecta L. (Slender Dayflower, Erect Dayflower)
  • Commelina virginica L. (Virginia Dayflower)
  • Comptonia peregrina (L.) Coult. (Sweet-fern)
  • Conardia compacta (Hook.) H. Rob.
  • Conioselinum chinense (L.) B.S.P. (Hemlock Parsley)
  • Conium maculatum L. (Poison Hemlock)
  • Conocephalum salebrosum Szweyk., Buczk. & Odrzyk.
  • Conoclinium coelestinum (L.) DC. (Mistflower, Ageratum)
  • Conopholis americana (L.) Wallroth (Squawroot, Bearcorn)
  • Conringia orientalis (Linnaeus) Andrzejowski (Hare's-ear Mustard, Treacle Mustard)
  • Consolida ajacis (L.) Schur. (Rocket Larkspur)
  • Convallaria majalis L. (European Lily-of-the-valley)
  • Convallaria pseudomajalis Bartram (American Lily-of-the-valley)
  • Convolvulus arvensis L. (Field Bindweed)
  • Corallorhiza bentleyi Freudenstein (Bentley's Coralroot)
  • Corallorhiza maculata (Raf.) Raf. var. maculata (Eastern Spotted Coralroot)
  • Corallorhiza maculata (Raf.) Raf. var. occidentalis (Lindley) Ames (Western Spotted Coralroot)
  • Corallorhiza odontorhiza (Willd.) Nuttall (Autumn Coralroot)
  • Corallorhiza trifida Chtelain (Early Coralroot, Northern Coralroot)
  • Corallorhiza wisteriana Conrad (Spring Coralroot)
  • Coreopsis auriculata L. (Larkspur Coreopsis)
  • Coreopsis falcata Boynton (Pool Coreopsis)
  • Coreopsis grandiflora Hogg ex Sweet var. harveyana (Gray) Sherff (Large-flowered Coreopsis)
  • Coreopsis lanceolata L. (Long-stalk Coreopsis)
  • Coreopsis linifolia Nutt. (Savanna Coreopsis)
  • Coreopsis major Walt. (Woodland Coreopsis)
  • Coreopsis pubescens Ell. (Hairy Coreopsis)
  • Coreopsis tinctoria Nutt. var. tinctoria (Plains Coreopsis, Golden Tickseed)
  • Coreopsis tripteris L. (Tall Coreopsis)
  • Coreopsis verticillata L. (Whorled Coreopsis, Thread-leaf Coreopsis)
  • Coreopsis delphiniifolia Lam. (Larkspur Coreopsis, Lobed Coreopsis)
  • Coriandrum sativum L. (Coriander, Cilantro)
  • Cortaderia selloana (Schultes & Schultes f.) Aschers. & Graebn. (Pampas Grass)
  • Corydalis flavula (Raf.) DC (Yellow Corydalis, Yellow Fumewort, Yellow Harlequin)
  • Corydalis incisa (Thunb.) Pers. (Incised Fumewort, Purple Keman)
  • Corydalis orthopoda Hayata
  • Corylus americana Walt. (American Hazelnut, American Filbert)
  • Corylus cornuta Marsh. var. cornuta (Beaked Hazelnut)
  • Coryphopteris simulata (Davenport) S.E. Fawcett (Bog Fern, Massachusetts Fern)
  • Coscinodon cribrosus (Hedw.) Spruce
  • Cosmos bipinnatus Cav. (Common Cosmos)
  • Cosmos sulphureus Cav. (Orange Cosmos)
  • Cota tinctoria (L.) J. Gay ex Guss. (Golden Chamomile)
  • Crataegus aemula Beadle (Rome Hawthorn)
  • Crataegus aprica Beadle (Sunny Hawthorn)
  • Crataegus beata Sargent (Red Hawthorn)
  • Crataegus berberifolia Torr. & Gray (Barberry Hawthorn)
  • Crataegus calpodendron (Ehrh.) Medik. (Pear Hawthorn)
  • Crataegus coccinea L. (Scarlet Hawthorn)
  • Crataegus collina Chapman (Hillside Hawthorn)
  • Crataegus compacta Sargent (Clustered Hawthorn, Thames Hawthorn)
  • Crataegus craytonii Beadle (Crayton's Hawthorn)
  • Crataegus crus-galli L. var. crus-galli (Cockspur Hawthorn)
  • Crataegus crus-galli L. var. pyracanthifolia Aiton (Narrowleaf Cockspur Hawthorn)
  • Crataegus dodgei Ashe (Dodge's Hawthorn)
  • Crataegus intricata Lange var. biltmoreana (Beadle) R.W. Lance (Biltmore Hawthorn)
  • Crataegus intricata Lange var. boyntonii (Beadle) Kruschke (Boynton's Hawthorn)
  • Crataegus intricata Lange var. intricata (Entangled Hawthorn)
  • Crataegus intricata Lange var. rubella (Beadle) Kruschke (Reddish Hawthorn)
  • Crataegus intricata Lange var. straminea (Beadle) E.J. Palmer (Yellow-fruited Hawthorn)
  • Crataegus iracunda Beadle (Forest Hawthorn)
  • Crataegus macrosperma Ashe (Big-fruited Hawthorn, Eastern Hawthorn)
  • Crataegus margarettae Ashe (Margaret's Hawthorn)
  • Crataegus marshallii Egglest. (Parsley Hawthorn)
  • Crataegus mollis Scheele var. mollis (Downy Hawthorn)
  • Crataegus monogyna Jacquin (English Hawthorn)
  • Crataegus pennsylvanica Ashe (Pennsylvania Hawthorn)
  • Crataegus pexa Beadle (Dwarf Hawthorn)
  • Crataegus phaenopyrum (L. f.) Medik. (Washington Hawthorn)
  • Crataegus pruinosa (Wendl. f.) K. Koch var. dissona (Sarg.) Eggelstone (Large-leaved Frosted Hawthorn)
  • Crataegus pruinosa (Wendl. f.) K. Koch var. gattingeri (Ashe) R.W. Lance (Gattinger's Hawthorn)
  • Crataegus pruinosa (Wendl. f.) K. Koch var. parvula (Sarg.) Phipps (Small-leaved Frosted Hawthorn)
  • Crataegus pruinosa (Wendl. f.) K. Koch var. pruinosa (Frosted Hawthorn)
  • Crataegus pruinosa (Wendl. f.) K. Koch var. rugosa (Ashe) Kruschke (Wide-leaved Frosted Hawthorn)
  • Crataegus pruinosa (Wendl.) K. Koch var. virella (Ashe) Kruschke
  • Crataegus punctata Jacq. (Dotted Hawthorn)
  • Crataegus scabrida Sargent var. asperifolia (Sargent) Kruschke (Rough Hawthorn)
  • Crataegus schuettei Ashe (Schuette's Hawthorn)
  • Crataegus succulenta Schrad. ex Link var. macracantha (Lodd. ex Loudon) Eggleston (Large-thorned Hawthorn)
  • Crataegus succulenta Schrad. ex Link var. neofluvialis (Ashe) E.J. Palmer (New River Hawthorn)
  • Crataegus succulenta Schrad. ex Link var. succulenta (Fleshy Hawthorn)
  • Crataegus uniflora Muenchh. (One-flowered Hawthorn)
  • Crataegus viridis L. var. viridis (Green Hawthorn)
  • Crataegus disperma Ashe (Two-seed Hawthorn)
  • Crataegus persimilis Sargent (Plumleaf Hawthorn)
  • Crataegus vailiae Britton (Vail's Hawthorn)
  • Cratoneuron filicinum (Hedw.) Spruce
  • Crepidomanes intricatum (Farrar) Ebihara & Weakley (Grotto-felt, Appalachian Trichomanes, Weft Fern)
  • Crepis capillaris (L.) Wallr. (Smooth Hawksbeard)
  • Crepis pulchra L. (Small-flower Hawksbeard)
  • Crepis tectorum L. (Narrowleaf Hawksbeard)
  • Crocanthemum bicknellii (Fernald) Barnhart (Plains Frostweed, Hoary Frostweed)
  • Crocanthemum canadense (L.) Britton (Canada Frostweed, Canada Sunrose)
  • Crocanthemum propinquum (Bicknell) Bicknell (Low Frostweed)
  • Croptilon divaricatum (Nutt.) Raf. (Scratch Daisy)
  • Crossocalyx hellerianus (Nees ex Lindenb.) Meyl. (Heller's Notchwort)
  • Crotalaria biflora L. (Two-flower Rattlebox)
  • Crotalaria pallida Aiton var. obovata (G. Don) Polhill (Smooth Rattlebox)
  • Crotalaria purshii DC. (Pursh's Rattlebox)
  • Crotalaria rotundifolia Walt. ex J.F. Gmel. (Low Rattlebox, Rabbitbells)
  • Crotalaria sagittalis L. (Rattlebox, Arrowhead Rattlebox)
  • Crotalaria spectabilis Roth (Showy Rattlebox)
  • Croton bonplandianus Baill. (Bonpland's Croton)
  • Croton capitatus Michx. (Woolly Croton, Hogwort)
  • Croton glandulosus L. var. septentrionalis Muell.-Arg. (Tropic Croton, Tooth-leaved Croton, Sand Croton)
  • Croton monanthogynus Michx. (Prairie Tea, One-seeded Croton)
  • Croton willdenowii Webster (Glade Rushfoil, Outcrop Rushfoil, Willdenow's Croton)
  • Cryphaea glomerata Schimp. ex Sull.
  • Cryphaea nervosa (Hook. & Wilson) Mll. Hal.
  • Cryphaea ravenelii Austin
  • Cryptotaenia canadensis (L.) DC. (Honewort)
  • Ctenidium molluscum (Hedw.) Mitt.
  • Ctenium aromaticum (Walt.) Wood (Toothache Grass, Orange Grass)
  • Cubelium concolor (T.F. Forst.) Raf. ex Britt. & A. Brown (Green Violet)
  • Cucumis melo L. (Cantaloupe)
  • Cucurbita pepo L. (Pumpkin)
  • Cunila origanoides (L.) Britt. (Common Dittany, Wild Oregano, Stonemint)
  • Cuphea carthagenensis (Jacq.) McBride (Colombian Waxweed)
  • Cuphea viscosissima Jacq. (Blue Waxweed, Clammy Cuphea)
  • Cuscuta campestris Yuncker (Field Dodder)
  • Cuscuta cephalanthi Engelm. (Buttonbush Dodder)
  • Cuscuta compacta Jussieu ex Choisy (Compact Dodder)
  • Cuscuta coryli Engelm. (Hazel Dodder)
  • Cuscuta gronovii Willd. ex Roem. & Schult. (Common Dodder)
  • Cuscuta indecora Choisy var. indecora (Big-seed Alfalfa Dodder, Large-seed Dodder, Pretty Dodder)
  • Cuscuta pentagona Engelm. (Five-angled Dodder)
  • Cuscuta polygonorum Engelm. (Smartweed Dodder)
  • Cuscuta rostrata Shuttlw. ex Engelm. & Gray (Beaked Dodder)
  • Cuthbertia graminea Small (Grasslike Roselings)
  • Cyanus segetum Hill (Cornflower, Bachelor's-buttons)
  • Cyclachaena xanthiifolia (Nutt.) Fresenius (Giant Sumpweed)
  • Cyclospermum leptophyllum (Pers.) Sprague ex Britt. & Wilson (Marsh Parsley)
  • Cymbalaria muralis P.G. Gaertn., B. Mey. & Scherb. ssp. muralis (Kenilworth-ivy)
  • Cymophyllus fraserianus (Ker-Gawler) Kartesz & Gandhi (Fraser's Sedge, Lily-leaf Sedge)
  • Cynanchum laeve (Michx.) Pers. (Honeyvine, Sandvine)
  • Cynodon dactylon (L.) Pers. (Bermuda Grass)
  • Cynoglossum officinale L. (Hound's-tongue)
  • Cynosurus echinatus L. (Rough Dogtail Grass, Bristly Dogtail Grass)
  • Cyperus acuminatus Torr. & Hook. (Taper-tip Flatsedge, Pale Umbrella-sedge)
  • Cyperus bipartitus Torrey (Slender Flatsedge, Shining Flatsedge)
  • Cyperus brevifolioides Thieret & Delahoussaye (Pasture Spikesedge, Asiatic Greenhead Sedge)
  • Cyperus compressus L. (Poorland Flatsedge)
  • Cyperus croceus Vahl (Baldwin's Flatsedge)
  • Cyperus dentatus Torrey (Toothed Flatsedge)
  • Cyperus diandrus Torrey (Umbrella Flatsedge)
  • Cyperus difformis L. (Variable Flatsedge)
  • Cyperus echinatus (L.) Wood (Globe Flatsedge)
  • Cyperus erythrorhizos Muhlenberg (Red-root Flatsedge)
  • Cyperus esculentus L. var. leptostachyus Bckler (Yellow Nutsedge, Yellow Nutgrass, Wild Chufa, Earth-almond)
  • Cyperus filicinus Vahl. (Fern Flatsedge)
  • Cyperus filiculmis Vahl. (Southeastern Flatsedge)
  • Cyperus flavescens L. (Yellow Flatsedge)
  • Cyperus flavicomus Michaux (White-edge Flatsedge)
  • Cyperus fuscus L. (Brown Galingale)
  • Cyperus granitophilus McVaugh (Granite Flatsedge)
  • Cyperus grayi Torrey (Gray's Flatsedge)
  • Cyperus haspan L. (Sheathed Flatsedge)
  • Cyperus hortensis (Salzmann ex Steudel) Dorr (Low Spikesedge)
  • Cyperus houghtonii Torrey (Houghton's Flatsedge)
  • Cyperus hystricinus Fernald (Bristly Flatsedge)
  • Cyperus iria L. (Rice-field Flatsedge)
  • Cyperus lancastriensis Porter ex Gray (Many-flowered Flatsedge)
  • Cyperus lupulinus (Sprengel) Marcks ssp. lupulinus (Upland Flatsedge)
  • Cyperus lupulinus (Sprengel) Marcks ssp. macilentus Fernald (Small-scale Upland Flatsedge)
  • Cyperus lupulinus complex
  • Cyperus microiria Steudel (Asian Flatsedge)
  • Cyperus neotropicalis Alain (American Halfchaff Sedge)
  • Cyperus odoratus L. var. engelmannii (Steud.) R. Carter, S.D. Jones, & Wipff (Slender Sand Sedge)
  • Cyperus odoratus L. var. odoratus (Fragrant Flatsedge, Rusty Flatsedge)
  • Cyperus odoratus L. var. squarrosus (N. Britt.) S.D. Jones, Wipff, & R. Carter
  • Cyperus plukenetii Fernald (Plukenet's Flatsedge)
  • Cyperus polystachyos Rottboell (Coast Flatsedge, Many-spike Flatsedge)
  • Cyperus pseudovegetus Steudel (Green Flatsedge, Marsh Flatsedge)
  • Cyperus refractus Engelm. ex Boeckl. (Reflexed Flatsedge)
  • Cyperus retrofractus (L.) Torrey (Rough Flatsedge)
  • Cyperus retrorsus Chapman (Pineland Flatsedge)
  • Cyperus rotundus L. (Purple Nutsedge, Nutgrass, Cocograss)
  • Cyperus squarrosus L. var. squarrosus (Awned Flatsedge)
  • Cyperus strigosus L. (Straw-colored Flatsedge)
  • Cyperus subsquarrosus (Muhl.) Bauters (Small-flower Halfchaff Sedge, Dwarf Bulrush)
  • Cyperus surinamensis Rottb. (Tropical Flatsedge)
  • Cyperus virens Michaux (Green Flatsedge)
  • Cypripedium acaule Aiton (Pink Lady's-slipper, Moccasin-flower)
  • Cypripedium candidum Muhl. ex Willd. (Small White Lady's-slipper)
  • Cypripedium kentuckiense C.F.Reed (Kentucky Lady's-slipper)
  • Cypripedium parviflorum Salisb. var. pubescens (Willd.) Knight (Large Yellow Lady's-slipper)
  • Cypripedium reginae Walter (Showy Lady's-slipper, Queen Lady's-slipper)
  • Cyrilla racemiflora L. (Swamp Cyrilla, Ti-ti)
  • Cyrto-hypnum minutulum (Hedw.) W.R. Buck & H.A. Crum
  • Cyrto-hypnum pygmaeum (Schimper) W. R. Buck & H. A. Crum
  • Cyrtomium falcatum (L.f.) K. Presl (Asian Net-vein Holly Fern)
  • Cystopteris bulbifera (L.) Bernh. (Bulblet Fern, Bulblet Bladder Fern)
  • Cystopteris protrusa (Weatherby) Blasdell (Lowland Bladder Fern, Lowland Brittle Fern)
  • Cystopteris tennesseensis Shaver (Tennessee Bladder Fern)
  • Cystopteris tenuis (Michx.) Desv. (Fragile Fern, Mackay's Bladder Fern)
  • Cytisus scoparius (L.) Link (Common Broom, Scotch Broom)
  • Dactylis glomerata L. (Orchard Grass)
  • Dactyloctenium aegyptium (L.) Willd. (Crowfoot Grass)
  • Dactylorhiza viridis (L.) R.M. Bateman Pridgeon, & M.W. Chase (Long-bracteate Green Orchid, Long-bracteate Frog Orchid)
  • Dalea leporina (Ait.) Bullock (Hare's-foot Dalea)
  • Dalibarda repens L. (Dewdrop, Robin-runaway, Star-violet)
  • Danthonia compressa Austin (Mountain Oatgrass)
  • Danthonia sericea Nutt. (Silky Oatgrass)
  • Danthonia spicata (L.) Beauv. ex Roemer & J.A. Schultes (Poverty Oatgrass)
  • Dasistoma macrophyllum (Nutt.) Raf. (Mullein Foxglove)
  • Datura stramonium L. (Jimson-weed)
  • Datura wrightii Regel (Indian-apple)
  • Daucus carota L. (Queen-Anne's Lace, Wild Carrot)
  • Daucus pusillus Michaux (American Queen Anne's Lace, American Wild Carrot)
  • Decodon verticillatus (L.) Ell. (Swamp Loosestrife, Water-willow)
  • Delphinium exaltatum Ait. (Tall Larkspur)
  • Delphinium tricorne Michx. (Dwarf Larkspur)
  • Dendrolycopodium dendroideum (Michx.) A. Haines (Tree Ground-pine, Prickly Tree-clubmoss, Round-branch Tree-clubmoss)
  • Dendrolycopodium hickeyi (W.H. Wagner, Beitel & Moran) A. Haines (Hickey's Ground-pine, Hickey's Tree-clubmoss)
  • Dendrolycopodium obscurum (L.) A. Haines (Common Ground-pine, Common Tree-clubmoss, Flat-branched Tree-clubmoss)
  • Deparia acrostichoides (Sw.) M. Kato (Silvery Spleenwort)
  • Deschampsia cespitosa (L.) Beauv. (Tufted Hairgrass)
  • Descurainia pinnata (Walter) Britton var. brachycarpa (Richardson) Fernald (Western Tansy Mustard)
  • Descurainia sophia (Linnaeus) Webb ex. Prantl (Common Tansy Mustard, Herb Sophia)
  • Desmanthus illinoensis (Michx.) MacMillan ex. Rob. & Fern. (Prairie Mimosa)
  • Desmodium canadense (L.) DC. (Showy Tick-trefoil, Canadian Tick-trefoil)
  • Desmodium canescens (L.) DC. (Hoary Tick-trefoil)
  • Desmodium ciliare (Muhl. ex Willd.) DC. (Hairy Small-leaf Tick-trefoil)
  • Desmodium cuspidatum (Muhl. ex Willd.) Loudon (Toothed Tick-trefoil, Large-bracted Tick-trefoil)
  • Desmodium fernaldii Schub. (Fernald's Tick-trefoil)
  • Desmodium glabellum (Michx.) DC. (Dillenius' Tick-trefoil)
  • Desmodium laevigatum (Nutt.) DC. (Smooth Tick-trefoil)
  • Desmodium lineatum DC. (Sand Tick-trefoil)
  • Desmodium marilandicum (L.) DC. (Smooth Small-leaf Tick-trefoil, Maryland Tick-trefoil)
  • Desmodium nuttallii (Schindl.) Schub. (Nuttall's Tick-trefoil)
  • Desmodium obtusum (Muhl. ex Willd.) DC. (Stiff Tick-trefoil)
  • Desmodium ochroleucum M.A. Curtis ex Canby (Cream-flowered Tick-trefoil)
  • Desmodium paniculatum (L.) DC. var. epetiolatum Schub. (Narrow-leaf Tick-trefoil, Panicled-leaf Tick-trefoil)
  • Desmodium paniculatum (L.) DC. var. paniculatum (Narrow-leaf Tick-trefoil, Panicled-leaf Tick-trefoil)
  • Desmodium perplexum Schub. (Perplexing Tick-trefoil)
  • Desmodium rotundifolium DC. (Round-leaf Tick-trefoil, Prostrate Tick-trefoil)
  • Desmodium sessilifolium (Torr.) Torr. & Gray (Sessile-leaf Tick-trefoil)
  • Desmodium strictum (Pursh) DC. (Pineland Tick-trefoil, Pine Barren Tick-Trefoil)
  • Desmodium tenuifolium Torr. & Gray (Slim-leaf Tick-trefoil)
  • Desmodium viridiflorum (L.) DC. (Velvet-leaf Tick-trefoil)
  • Deutzia scabra Thunb. (Fuzzy Deutzia)
  • Diamorpha smallii Britt. ex Small (Small's Stonecrop, Elf-orpine)
  • Dianthus armeria L. (Deptford Pink)
  • Dianthus barbatus L. ssp. barbatus (Sweet William)
  • Dianthus deltoides L. ssp. deltoides (Maiden Pink, Meadow Pink)
  • Dianthus plumarius L. ssp. plumarius (Garden Pink)
  • Diarrhena americana Beauv. (American Beakgrain, Eastern Beakgrain)
  • Diarrhena obovata (Gleason) Brandenburg (Western Beakgrain)
  • Dicentra canadensis (Goldie) Walp. (Squirrel Corn)
  • Dicentra cucullaria (L.) Bernh. (Dutchman's Breeches)
  • Dicentra eximia (Ker-Gawl.) Torr. (Wild Bleeding Heart)
  • Dichanthelium aciculare (Desv. ex Poir.) Gould & C.A. Clark (Needle-leaf Panic Grass, Needle-leaf Witchgrass)
  • Dichanthelium acuminatum (Sw.) Gould & C.A. Clark var. acuminatum (Woolly Panic Grass, Woolly Witchgrass)
  • Dichanthelium acuminatum (Sw.) Gould & C.A. Clark var. fasciculatum (Torr.) Freckmann (Slender-stemmed Panic Grass, Slender-stemmed Witchgrass)
  • Dichanthelium acuminatum (Sw.) Gould & C.A. Clark var. lindheimeri (Nash) Gould & C.A. Clark (Lindheimer's Panic Grass, Lindheimer's Witchgrass)
  • Dichanthelium acuminatum complex
  • Dichanthelium angustifolium (Ell.) Gould (Narrow-leaved Panic Grass, Narrow-leaved Witchgrass)
  • Dichanthelium annulum (Ashe) LeBlond (Ringed Panic Grass, Ringed Witchgrass)
  • Dichanthelium appalachiense Townsend & LeBlond (Appalachian Panic Grass, Appalachian Witchgrass)
  • Dichanthelium arenicoloides (Ashe) LeBlond (Sandy Woods Panic Grass, Sandy Woods Witchgrass)
  • Dichanthelium bicknellii (Nash) LeBlond (Bicknell's Panic Grass, Bicknell's Witchgrass)
  • Dichanthelium boscii (Poir.) Gould & C.A. Clark (Bosc's Panic Grass, Bosc's Witchgrass)
  • Dichanthelium caerulescens (Hack. ex Fitchc.) Correll (Blue Panic Grass, Blue Witchgrass)
  • Dichanthelium clandestinum (L.) Gould (Deer-Tongue Grass)
  • Dichanthelium columbianum (Scribn.) Freckmann (American Witchgrass)
  • Dichanthelium commutatum (J.A. Schultes) Gould (Variable Panic Grass, Ashe's Panic Grass)
  • Dichanthelium commutatum (J.A. Schultes) Gould var. ashei (Pearson ex Ashe) Mohlenbrock (Ashe's Panic Grass, Ashe's Witchgrass)
  • Dichanthelium commutatum (J.A. Schultes) Gould var. commutatum (Variable Panic Grass, Variable Witchgrass)
  • Dichanthelium consanguineum (Kunth) Gould & C.A. Clark (Blood Panic Grass, Blood Witchgrass)
  • Dichanthelium cryptanthum (Ashe) LeBlond (Hidden-flowered Panic Grass, Hidden-flowered Witchgrass)
  • Dichanthelium curtifolium (Nash) LeBlond (Short-leaf Panic Grass, Short-leaf Witchgrass)
  • Dichanthelium depauperatum (Muhl.) Gould (Starved Panic Grass, Starved Witchgrass)
  • Dichanthelium dichotomum (L.) Gould var. dichotomum (Small-fruited Panic Grass, Forked Witchgrass)
  • Dichanthelium dichotomum (L.) Gould var. nitidum (Lam.) LeBlond (Shining Panic Grass, Shining Witchgrass)
  • Dichanthelium dichotomum complex
  • Dichanthelium ensifolium (Baldwin ex Elliott) Gould (Small-leaved Panic Grass, Small-leaved Witchgrass)
  • Dichanthelium filiramum (Ashe) LeBlond
  • Dichanthelium harvillii Ludwig & LeBlond (Harvill's Panic Grass, Harvill's Witchgrass)
  • Dichanthelium inflatum (Scribn. & J.G. Sm.) J.R. Thomas
  • Dichanthelium latifolium (L.) Harvill (Broad-leaf Panic Grass, Broad-leaf Witchgrass)
  • Dichanthelium laxiflorum (Lam.) Gould (Open-flower Panic Grass, Open-flower Witchgrass)
  • Dichanthelium leucothrix (Nash) Freckmann (Rough Panic Grass, Rough Witchgrass)
  • Dichanthelium linearifolium (Scribn.) Gould (Slim-leaf Panic Grass, Linear-leaf Panic Grass, Slim-leaf Witchgrass)
  • Dichanthelium longiligulatum (Nash) Freckmann (Coastal Plain Panic Grass, Coastal Plain Witchgrass)
  • Dichanthelium lucidum (Ashe) LeBlond (Bog Panic Grass, Bog Witchgrass)
  • Dichanthelium mattamuskeetense (Ashe) Mohlenbrock (Mattamuskeet Panic Grass, Mattamuskeet Witchgrass)
  • Dichanthelium meridionale (Ashe) Freckmann (Matting Panic Grass, Matting Witchgrass)
  • Dichanthelium microcarpon (Muhl. ex Elliott) Mohlenbrock (Branched Panic Grass, Small-fruited Witchgrass)
  • Dichanthelium mundum (Fern.) LeBlond (Elegant Witchgrass)
  • Dichanthelium mutabile (Scribner & J.G. Smith ex Nash) Wipff
  • Dichanthelium oligosanthes (J.A. Schultes) Gould (Few-flowered Panic Grass, Few-flowered Witchgrass)
  • Dichanthelium ovale (Ell.) Gould & C.A. Clark var. addisonii (Nash) Gould & C.A. Clark (Addison's Panic Grass, Addison's Witchgrass)
  • Dichanthelium ovale (Ell.) Gould & C.A. Clark var. ovale (Oval-flowered Panic Grass, Oval-flowered Witchgrass)
  • Dichanthelium polyanthes (Schultes) Mohlenbrock (Round-seed Panic Grass, Many-flowered Witchgrass)
  • Dichanthelium portoricense (Desv. ex Ham.) B.F. Hansen & Wunderlin ssp. patulum (Scribn. & Murr.) Freckmann & Lelong (Hemlock Panic Grass, Hemlock Witchgrass)
  • Dichanthelium portoricense (Desv. ex Ham.) B.F. Hansen & Wunderlin ssp. portoricense (Puerto Rican Panic Grass, Puerto Rican Witchgrass)
  • Dichanthelium ravenelii (Scribn. & Merr.) Gould (Ravenel's Panic Grass, Ravenel's Witchgrass)
  • Dichanthelium recognitum (Fernald) LeBlond (Novel Witchgrass, Novel Witchgrass)
  • Dichanthelium roanokense (Ashe) LeBlond (Roanoke Panic Grass, Roanoke Witchgrass)
  • Dichanthelium scabriusculum (Ell.) Gould & C.A. Clark (Tall Swamp Panic Grass, Tall Swamp Witchgrass)
  • Dichanthelium scoparium (Lam.) Gould (Velvet Panic Grass, Velvet Witchgrass)
  • Dichanthelium scribnerianum (Nash) J.R. Thomas (Scribner's Panic Grass, Scribner's Witchgrass)
  • Dichanthelium sphaerocarpon (Ell.) Gould (Round-fruited Panic Grass, Round-fruited Witchgrass)
  • Dichanthelium spretum (J.A. Schultes) Freckmann (Eaton's Panic Grass, Eaton's Witchgrass)
  • Dichanthelium strigosum (Muhl. ex. Ell.) Freckmann var. strigosum (Rough-hair Panic Grass, Rough-hair witchgrass)
  • Dichanthelium tenue (Muhl.) Freckmann & Lelong (White-edged Panic Grass, White-edged Witchgrass)
  • Dichanthelium villosissimum (Nash) Freckmann var. villosissimum (White-haired Panic Grass, White-haired Witchgrass)
  • Dichanthelium wrightianum (Scribn.) Freckmann (Wright's Panic Grass, Wright's Witchgrass)
  • Dichanthelium yadkinense (Ashe) Mohlenbrock (Spotted-sheath Panic Grass, Spotted-sheath Witchgrass)
  • Dichelyma capillaceum (With.) Myrin
  • Dichodontium pellucidum (Hedw.) Schimp.
  • Dichondra carolinensis Michx. (Carolina Ponyfoot)
  • Dicliptera brachiata (Pursh) Sprengel (Branched Dicliptera, Branched Fold-wing, Wild Mudwort)
  • Dicranella heteromalla (Hedw.) Schimp (Fine Hair Moss)
  • Dicranella rufescens (With.) Schimp.
  • Dicranella varia (Hedw.) Schimp.
  • Dicranodontium asperulum (Mitt.) Broth.
  • Dicranodontium denudatum (Brid.) E. Britton
  • Dicranoweisia crispula (Hedw.) Milde
  • Dicranum bonjeanii De Notaris
  • Dicranum condensatum Hedw.
  • Dicranum flagellare Hedwig
  • Dicranum fulvum Hooker (Boulder Broom Moss)
  • Dicranum fuscescens Turner var. fuscescens (Curly Broom Moss)
  • Dicranum montanum Hedwig (Crispy Broom Moss)
  • Dicranum muehlenbeckii Bruch & Schimp.
  • Dicranum polysetum Swartz (Wrinkled Broom Moss)
  • Dicranum scoparium Hedwig (Common Broom Moss)
  • Dicranum spurium Hedwig
  • Dicranum undulatum Schrad. ex Brid.
  • Dicranum viride (Sull. & Lesq.) Lindb. (Brittle Broom Moss)
  • Didiplis diandra (Nutt. ex DC.) Wood (Water-purslane)
  • Didymodon fallax (Hedw.) R.H. Zander
  • Didymodon ferrugineus (Schimp. ex Besch.) M.O. Hill
  • Didymodon rigidulus Hedw. var. rigidulus
  • Didymodon tophaceus (Brid.) Lisa
  • Diervilla lonicera Miller (Northern Bush-honeysuckle)
  • Digitalis purpurea L. (Purple Foxglove)
  • Digitaria ciliaris (Retz.) Koeler (Southern Crabgrass)
  • Digitaria filiformis (L.) Koeler var. filiformis (Slender Crabgrass)
  • Digitaria ischaemum (Schreb.) Muhl. (Smooth Crabgrass)
  • Digitaria sanguinalis (L.) Scop. (Northern Crabgrass)
  • Digitaria sanguinalis / ciliaris complex (Hairy Crabgrass, Big Crabgrass, Southern Crabgrass)
  • Digitaria serotina (Walt.) Michx. (Dwarf Crabgrass)
  • Digitaria texana A.S. Hitchc. (Texas Crabgrass)
  • Digitaria villosa (Walt.) Pers. (Shaggy Crabgrass)
  • Digitaria violascens Link. (Violet Crabgrass)
  • Dinebra panicea (Retz.) P.M. Peterson & N. Snow ssp. brachiata (Steud.) P.M. Peterson & N. Snow (Red Sprangletop)
  • Dinebra panicoides (J. Presl.) P.M. Peterson & N. Snow (Amazon Sprangletop)
  • Diodia virginiana L. (Virginia Buttonweed)
  • Dioscorea polystachya Turczaninow (Chinese Yam, Cinnamon Vine)
  • Dioscorea villosa L. (Wild Yam)
  • Diospyros virginiana L. (Common Persimmon, American Persimmon)
  • Diphasiastrum digitatum (Dill. ex A. Braun) Holub (Common Running-cedar, Common Running-pine)
  • Diphasiastrum tristachyum (Pursh) Holub (Ground-cedar, Blue Running-cedar)
  • Diphasiastrum habereri (House) Holub
  • Diphylleia cymosa Michx. (Umbrella-leaf)
  • Diphyscium foliosum (Hedw.) D. Mohr
  • Diphyscium mucronifolium Mitt.
  • Diplachne fusca (L.) P. Beauv. ex Roem. & Schult. ssp. fascicularis (Lam.). P.M. Peterson & N. Snow (Bearded Sprangletop, Long-awned Sprangletop, Salt-meadow Grass)
  • Diplachne fusca (L.) P. Beauv. ex Roem. & Schult. ssp. uninervia (J. Presl) P.M. Peterson & N. Snow (Mexican Sprangletop)
  • Diplophyllum andrewsii A. Evans
  • Diplophyllum apiculatum (A. Evans) Steph.
  • Diplophyllum taxifolium (Wahlenb.) Dumort.
  • Diplotaxis muralis (Linnaeus) A. P. DeCandolle (Annual Wall-rocket)
  • Diplotaxis tenuifolia (Linnaeus)A. P. DeCandolle (Perennial Wall-rocket)
  • Dipsacus fullonum L. (Wild Teasel, Common Teasel)
  • Dipsacus laciniatus L. (Cut-leaf Teasel)
  • Dirca palustris L. (Leatherwood)
  • Distichium capillaceum (Hedw.) Bruch & Schimp.
  • Distichlis spicata (L.) Greene (Saltgrass)
  • Ditrichum lineare (Sw.) Lindb.
  • Ditrichum pallidum (Hedw.) Hampe (Saffron Moss)
  • Ditrichum pusillum (Hedw.) Hampe
  • Ditrichum rhynchostegium Kindb.
  • Doellingeria infirma (Michx.) Greene (Cornel-leaved Aster)
  • Doellingeria umbellata (P. Mill.) Nees var. umbellata (Tall Flat-topped White Aster)
  • Draba ramosissima Desvaux (Rocktwist)
  • Draba verna Linnaeus (Whitlow-grass)
  • Drepanocladus aduncus (Hedw.) Warnst.
  • Drepanocladus polygamus (Schimp.) Hedens (Stiff Star Moss)
  • Drepanolejeunea appalachiana R.M. Schuster (Appalachian Threadwort)
  • Drosera brevifolia Pursh (Dwarf Sundew)
  • Drosera capillaris Poir. (Pink Sundew)
  • Drosera intermedia Hayne (Water Sundew, Spoonleaf Sundew)
  • Drosera rotundifolia L. (Roundleaf Sundew)
  • Drummondia prorepens (Hedw.) E. Britton
  • Drymocallis arguta (Pursh) Rydberg (Tall Cinquefoil, Sticky Cinquefoil)
  • Dryopteris campyloptera (Kunze) Clarkson (Mountain Wood Fern)
  • Dryopteris campyloptera intermedia
  • Dryopteris carthusiana (Vill.) H.P. Fuchs (Spinulose Wood Fern, Toothed Wood Fern)
  • Dryopteris celsa (Wm. Palmer) Knowlt., Palmer & Pollard ex Small (Log Fern)
  • Dryopteris celsa cristata
  • Dryopteris clintoniana (D.C. Eaton) Dowell (Clinton's Wood Fern, Broad Swamp Fern)
  • Dryopteris clintoniana cristata
  • Dryopteris clintoniana marginalis
  • Dryopteris cristata (L.) Gray (Crested Wood Fern, Crested Fern)
  • Dryopteris cristata goldieana
  • Dryopteris erythrosora (D.C. Eaton) Kuntze (Japanese Red Shield Fern)
  • Dryopteris goldieana (Hook. ex Goldie) Gray (Goldie's Wood Fern)
  • Dryopteris intermedia (Muhl. ex Willd.) Gray (Evergreen Wood Fern, Fancy Fern)
  • Dryopteris intermedia marginalis
  • Dryopteris marginalis (L.) Gray (Marginal Wood Fern)
  • Dryopteris australis (Wherry) Small
  • Dryopteris boottii (Tuckerman) Underwood
  • Dryopteris neowherryi W.H. Wagner
  • Dryopteris separabilis Small
  • Dryopteris slossoniae Wherry ex Lellinger
  • Dryopteris triploidea Wherry
  • Dryopteris uliginosa (A. Braun ex Dowell) Druce
  • Dulichium arundinaceum (L.) Britton var. arundinaceum (Three-way Sedge)
  • Dumortiera hirsuta (Sw.) Nees
  • Dysphania ambrosioides (L.) Mosyakin & Clemants (Mexican Tea, Wormseed, Epazote)
  • Dysphania atriplicifolia (Sprengel) G. Kadereit (Winged Pigweed)
  • Dysphania botrys (L.) Mosyakin & Clemants (Jerusalem-oak, Feather-geranium)
  • Dysphania pumilio (R. Br.) Mosyakin & Clemants (Clammy Goosefoot)
  • Dyssodia papposa (Ventenat) A.S. Hitchcock. (Dogweed, Fetid Marigold)
  • Echinacea laevigata (C.L. Boynt. & Beadle) Blake (Smooth Coneflower)
  • Echinacea pallida (Nutt.) Nutt. (Pale Purple Coneflower)
  • Echinacea purpurea (L.) Moench (Purple Coneflower)
  • Echinochloa colonum (L.) Link (Jungle-rice)
  • Echinochloa crus-galli (L.) Beauv. var. crus-galli (Barnyard Grass)
  • Echinochloa frumentacea Link (Japanese Millet, Siberian Millet, Billion-dollar Grass)
  • Echinochloa muricata (Beauv.) Fern. var. microstachya Wieg. (Rough Barnyard Grass)
  • Echinochloa muricata (Beauv.) Fern. var. muricata (Rough Barnyard Grass)
  • Echinochloa walteri (Pursh) Heller (Swamp Barnyard Grass, Coast Cockspur Grass)
  • Echinocystis lobata (Michx.) Torrey & A. Gray (Wild Cucumber, Prickly Cucumber, Wild Balsam-apple)
  • Echinodorus cordifolius (L.) Grisebach (Creeping Burhead)
  • Echinops sphaerocephalus L. (Giant Globe-thistle)
  • Echium vulgare L. (Viper's Bugloss, Blueweed)
  • Eclipta prostrata (L.) L. (False Daisy, Yerba-de-tajo)
  • Edrastima uniflora (L.) Raf. (Clustered Bluets)
  • Egeria densa Planchon (Brazilian Waterweed)
  • Elaeagnus angustifolia L. (Russian Olive, Oleaster)
  • Elaeagnus multiflora Thunb. (Cherry Silverberry)
  • Elaeagnus pungens Thunb. (Thorny Olive)
  • Elaeagnus umbellata Thunb. (Autumn Olive)
  • Elatine americana (Pursh) Arnott (American Waterwort)
  • Elatine minima (Nutt.) Fisch. & C.A. Mey. (Small Waterwort)
  • Eleocharis acicularis (L.) Roemer & Schultes (Needle Spikerush)
  • Eleocharis albida Torrey (White Spikerush)
  • Eleocharis atropurpurea (Retz) Presl & Presl (Purple Spikerush)
  • Eleocharis baldwinii (Torrey) Chapman (Baldwin's Spikerush)
  • Eleocharis bifida S.G. Smith (Bifid Spikerush)
  • Eleocharis compressa Sullivant var. compressa (Flattened Spikerush)
  • Eleocharis elliptica Kunth (Elliptic Spikerush)
  • Eleocharis engelmannii Steudel (Engelmann Spikerush)
  • Eleocharis equisetoides (Elliott) Torrey (Horsetail Spikerush)
  • Eleocharis erythropoda Steudel (Bald Spikerush)
  • Eleocharis fallax Weatherby (Creeping Spikerush)
  • Eleocharis flavescens (Poiret) Urban (Yellow Spikerush, Pale Spikerush)
  • Eleocharis intermedia Schultes (Matted Spikerush)
  • Eleocharis melanocarpa Torrey (Black-fruited Spikerush)
  • Eleocharis microcarpa Torrey var. filiculmis Torrey (Small-fruited Spikerush)
  • Eleocharis obtusa (Willd.) Schultes (Blunt Spikerush)
  • Eleocharis olivacea Torrey var. olivacea (Bright Green Spikerush)
  • Eleocharis palustris (L.) Roemer & Schultes (Common Spikerush)
  • Eleocharis parvula (R. & S.) Link ex Bluff, Nees & Schauer (Dwarf Spikerush, Small Spikerush)
  • Eleocharis quadrangulata (Michaux) R. & S. (Square-stem Spikerush)
  • Eleocharis radicans (Poiret) Kunth (Rooted Spikerush)
  • Eleocharis robbinsii Oakes (Robbins' Spikerush)
  • Eleocharis rostellata (Torrey) Torrey (Beaked Spikerush)
  • Eleocharis tenuis (Willd.) Schultes var. pseudoptera (Weath.) Svens. (Sharp-angled Spikerush)
  • Eleocharis tenuis (Willd.) Schultes var. tenuis (Slender Spikerush)
  • Eleocharis tortilis (Link) Schultes (Twisted Spikerush)
  • Eleocharis tricostata Torrey (Three-angled Spikerush)
  • Eleocharis tuberculosa (Michx.) Schultes (Long-tubercled Spikerush, Cone-cup Spikerush)
  • Eleocharis uniglumis (Link) Schultes (One-scale Spikerush)
  • Eleocharis verrucosa (Svens.) Harms (Warty Spikerush)
  • Eleocharis vivipara Link (Viviparous Spikerush)
  • Eleocharis wolfii (Gray) Gray ex Britt. in H.N. Patterson (Wolf's Spikerush)
  • Elephantopus carolinianus Raeusch. (Carolina Elephant's-foot)
  • Elephantopus nudatus Gray (Smooth Elephant's-foot)
  • Elephantopus tomentosus L. (Hairy Elephant's-foot, Devil's Grandmother)
  • Eleusine indica (L.) Gaertn. (Indian Goosegrass, Yard Grass)
  • Eleutherococcus sieboldianus (Makino) Koidz. (Five-leaf Aralia)
  • Ellisia nyctelea (L.) L. (Nyctelea, Waterpod, Aunt Lucy)
  • Elodea canadensis Michx. (Common Waterweed)
  • Elodea nuttallii (Planchon) St. John (Nuttall's Waterweed, Free-flowered Waterweed)
  • Elodium paludosum Austin
  • Elsholtzia ciliata (Thunb.) Hyl. (Crested Latesummer Mint, Vietnamese Balm)
  • Elymus canadensis L. var. canadensis (Nodding Wild Rye)
  • Elymus glabriflorus (Vasey ex L.H. Dewey) Scribn. & C.R. Ball (Southeastern Wild Rye)
  • Elymus glabriflorus (Vasey ex L.H. Dewey) Scribn. & C.R. Ball var. australis (Scribn. & C.R. Ball) J.J.N. Campbell (Hairy Southeastern Wild Rye)
  • Elymus glabriflorus (Vasey ex L.H. Dewey) Scribn. & C.R. Ball var. glabriflorus (Smooth Southeastern Wild Rye)
  • Elymus hystrix L. var. hystrix (Bottlebrush Grass)
  • Elymus hystrix L. var. piedmontanus Poindexter & Weakley (Piedmont Bottlebrush Grass)
  • Elymus macgregorii Brooks & Campbell (Early Wild Rye, MacGregor's Wild Rye)
  • Elymus repens (L.) Gould (Quackgrass, Dog Grass)
  • Elymus riparius Wieg. (Riverbank Wild Rye)
  • Elymus trachycaulus (Link) Gould ex Shinners ssp. trachycaulus (Slender Wheatgrass)
  • Elymus villosus Muhl. ex Willd. (Hairy Wild Rye, Downy Wild Rye)
  • Elymus virginicus L. var. halophilus (Bickn.) Wieg. (Virginia Wild Rye)
  • Elymus virginicus L. var. intermedius (Vasey ex . Gray) Bush (Virginia Wild Rye)
  • Elymus virginicus L. var. jejunus (Ramalay) Bush (Virginia Wild Rye)
  • Elymus virginicus L. var. virginicus (Virginia Wild Rye)
  • Emblica urinaria (Linnaeus) R.W. Bouman (Chamber Bitter)
  • Encalypta ciliata Hedw.
  • Encalypta procera Bruch
  • Endodeca serpentaria (L.) Raf. (Virginia Snakeroot, Turpentine-root)
  • Endotropis alnifolia (L'Her.) Hauensch. (Alder-leaved Buckthorn, American Alder-Buckthorn)
  • Endotropis lanceolata (Pursh) Hauensch. (Lance-Leaved Buckthorn)
  • Enemion biternatum Raf. (False Rue-anemone)
  • Entodon brevisetus (Hook. & Wilson) Lindb.
  • Entodon challengeri (Paris) Cardot
  • Entodon cladorrhizans (Hedw.) Mll. Hal.
  • Entodon macropodus (Hedw.) Mll. Hal.
  • Entodon seductrix (Hedw.) Mll. Hal.
  • Entodon sullivantii (Mll. Hal.) Lindb.
  • Ephemerum cohaerens (Hedwig) Hampe
  • Ephemerum crassinervium (Schwgr.) Hampe var. crassinervium
  • Ephemerum serratum (Schreb. ex Hedw.) Hampe
  • Ephemerum spinulosum Bruch & Schimper
  • Epifagus virginiana (L.) W.Barton (Beechdrops)
  • Epigaea repens L. (Trailing Arbutus)
  • Epilobium ciliatum Raf. ssp. ciliatum (American Willow-herb, Fringed Willow-herb, Hairy Willow-herb)
  • Epilobium coloratum Biehler (Purple-leaved Willow-herb)
  • Epilobium leptophyllum Raf. (Bog Willow-herb, Linear-leaved Willow-herb, Narrow-leaved Willow-herb)
  • Epilobium parviflorum Schreber (Smallflower Hairy Willowherb)
  • Epipactis helleborine (L.) Crantz (Helleborine)
  • Equisetum arvense L. (Field Horsetail)
  • Equisetum fluviatile L. (Water Horsetail)
  • Equisetum laevigatum A. Braun (Smooth Scouring-Rush)
  • Equisetum praealtum Rafinesque (Tall Scouring-Rush)
  • Equisetum sylvaticum L. (Woodland Horsetail)
  • Eragrostis capillaris (L.) Nees (Lacegrass)
  • Eragrostis cilianensis (All.) Vignola. ex Janchen (Stinkgrass)
  • Eragrostis curvula (Schrad.) Nees (Weeping Lovegrass)
  • Eragrostis frankii C.A. Mey. ex Steud. (Sandbar Lovegrass, Frank's Lovegrass)
  • Eragrostis hirsuta (Michx.) Nees (Big-top Lovegrass)
  • Eragrostis hypnoides (Lam.) B.S.P. (Creeping Lovegrass)
  • Eragrostis intermedia A.S. Hitchc. (Plains Lovegrass)
  • Eragrostis minor Host (Little Lovegrass)
  • Eragrostis pectinacea (Michx.) Nees var. pectinacea (Tufted Lovegrass, Carolina Lovegrass, Western Lovegrass)
  • Eragrostis pilosa (L.) Beauv. var. pilosa (India Lovegrass)
  • Eragrostis refracta (Muhl.) Scribn. (Coastal Lovegrass)
  • Eragrostis secundiflora J. Presl ssp. oxylepis (Torr.) S.D. Koch (Red Lovegrass)
  • Eragrostis spectabilis (Pursh) Steud. (Purple Lovegrass, Tumblegrass)
  • Eragrostis trichodes (Nutt.) Wood (Sand Lovegrass)
  • Eranthis hyemalis (L.) Salisb. (Winter-aconite)
  • Erechtites hieraciifolius (L.) Raf. ex DC. (Fireweed, Pilewort, American Burnweed)
  • Eremochloa ophiuroides (Munro) Hack. (Centipede Grass)
  • Erianthus alopecuroides (L.) Ell. (Silver Plumegrass, Woolly Plumegrass)
  • Erianthus coarctatus Fernald (Compressed Plumegrass, Brown Plumegrass)
  • Erianthus contortus Ell. (Spiral-awned Plumegrass, Short-beard Plumegrass)
  • Erianthus giganteus (Walt.) P. Beauv. (Giant Plumegrass, Sugarcane Plumegrass)
  • Erianthus strictus Baldwin (Narrow Plumegrass, Slender Plumegrass)
  • Erigenia bulbosa (Michx.) Nutt. (Harbinger-of-Spring)
  • Erigeron annuus (L.) Pers. (Annual Fleabane)
  • Erigeron bonariensis L. (Asthma-weed)
  • Erigeron canadensis L. (Horseweed, Common Horseweed)
  • Erigeron philadelphicus L. var. philadelphicus (Philadelphia Fleabane)
  • Erigeron pulchellus Michx. var. pulchellus (Robin's Plantain)
  • Erigeron pusillus Nutt. (Southern Horseweed)
  • Erigeron quercifolius Lam. (Oak-leaf Fleabane, Southern Fleabane)
  • Erigeron strigosus Muhl. ex Willd. var. strigosus (Daisy Fleabane)
  • Erigeron vernus (L.) Torr. & Gray (White-top Fleabane)
  • Eriocaulon aquaticum (Hill) Druce (Seven-angled Pipewort)
  • Eriocaulon decangulare L. var. decangulare (Ten-angled Pipewort)
  • Eriocaulon parkeri B.L.Robinson (Parker's Pipewort)
  • Eriochloa acuminata (J. Presl) Kunth var. acuminata (Taper-tip Cupgrass)
  • Eriochloa contracta A.S. Hitchc. (Prairie Cupgrass)
  • Eriochloa villosa (Thunb.) Kunth (Chinese Cupgrass)
  • Eriogonum allenii S. Wats. in A. Gray et al. (Shale Barren Wild Buckwheat)
  • Eriophorum virginicum L. (Tawny Cottongrass)
  • Erodium cicutarium (L.) L'Her. ex Ait. (Common Storksbill, Heron's-bill, Red-stem Filaree, Alfileria)
  • Eryngium aquaticum L. var. aquaticum (Rattlesnake-master, Marsh Eryngo)
  • Eryngium integrifolium Walter (Blue-flower Eryngo)
  • Eryngium prostratum Nutt. ex DC. (Creeping Eryngo)
  • Eryngium yuccifolium Michx. var. yuccifolium (Northern Rattlesnake-master, Button Eryngo)
  • Erysimum capitatum (Douglas ex. Hooker) E. L. Greene var. capitatum (Western Wallflower)
  • Erysimum cheiranthoides Linnaeus (Wormseed Wallflower)
  • Erysimum repandum Linnaeus (Spreading Wallflower, Bushy Wallflower, Treacle Mustard)
  • Erythranthe moschata (Douglas ex Lindley) Nesom (Muskflower)
  • Erythronium albidum Nutt. (White Trout Lily)
  • Erythronium americanum Ker-Gawl. ssp. americanum (Yellow Trout Lily, American Trout Lily)
  • Erythronium umbilicatum Parks & Hardin ssp. umbilicatum (Dimpled Trout Lily)
  • Eubotrys racemosus (L.) Nutt. (Fetterbush, Swamp Dog-hobble)
  • Eubotrys recurvus (Buckl.) Britt. (Mountain Fetterbush)
  • Eucladium verticillatum (Hedw.) Bruch & Schimp.
  • Euonymus alatus (Thunb.) Sieb. (Winged Euonymus, Burning Bush)
  • Euonymus americanus L. (Strawberry-bush, American Strawberry-bush, Heart's-a-bustin')
  • Euonymus atropurpureus Jacq. (Eastern Wahoo)
  • Euonymus europaeus L. (European Spindle Tree)
  • Euonymus fortunei (Turcz.) Hand.-Maz. (Winter Creeper, Climbing Euonymus)
  • Euonymus japonicus Thunb. (Japanese Spindle Tree)
  • Euonymus kiautschovicus Loes. (Spreading Euonymus)
  • Eupatorium album L. (White Thoroughwort)
  • Eupatorium altissimum L. (Tall Thoroughwort)
  • Eupatorium cannabinum L. (Hemp-agrimony)
  • Eupatorium capillifolium (Lam.) Small (Dog-fennel)
  • Eupatorium cordigerum (Fernald) Fernald (Clasping Round-leaf Thoroughwort)
  • Eupatorium glaucescens Ell. (Wedge-leaf Thoroughwort)
  • Eupatorium godfreyanum Cronq. (Godfrey's Thoroughwort)
  • Eupatorium hyssopifolium L. (Hyssop-leaf Thoroughwort)
  • Eupatorium leucolepis (DC.) Torr. & Gray (White-bracted Thoroughwort, Justice-weed)
  • Eupatorium linearifolium Walt. (Narrow-leaf Bushy Thoroughwort)
  • Eupatorium maritimum E.E. Schilling (Maritime Thoroughwort)
  • Eupatorium mohrii Greene (Mohr's Thoroughwort)
  • Eupatorium perfoliatum L. (Boneset, Common Boneset)
  • Eupatorium pilosum Walt. (Vervain Thoroughwort, Rough Boneset)
  • Eupatorium pubescens Muhl. ex Willd. (Hairy Thoroughwort, Hairy Boneset)
  • Eupatorium rotundifolium L. (Roundleaf Thoroughwort, Roundleaf Boneset)
  • Eupatorium saltuense Fern. (Pasture Thoroughwort)
  • Eupatorium semiserratum DC. (Small-flower Thoroughwort)
  • Eupatorium serotinum Michx. (Late Thoroughwort)
  • Eupatorium sessilifolium L. (Upland Boneset)
  • Eupatorium torreyanum Short and Peter (Torrey's Thoroughwort)
  • Eupatorium vaseyi Porter (Vasey's Thoroughwort)
  • Euphorbia bombensis Jacquin (Southern Seaside Spurge, Dixie Sandmat)
  • Euphorbia commutata Engelm. (Wood Spurge, Tinted Woodland Spurge)
  • Euphorbia corollata L. (Flowering Spurge)
  • Euphorbia cyathophora Murr. (Wild Poinsettia, Fire-on-the-Mountain)
  • Euphorbia cyparissias L. (Cypress Spurge)
  • Euphorbia davidii Subils (Davids Spurge)
  • Euphorbia dentata Michx. (Toothed Spurge, Green Poinsettia)
  • Euphorbia exserta (Small) Coker (Maroon Sandhills Spurge, Coastal Sand Spurge)
  • Euphorbia falcata L. (Crescent Spurge, Sickle Spurge)
  • Euphorbia helioscopia L. (Sun Spurge, Wartweed)
  • Euphorbia hirta L. (Pillpod Sandmat)
  • Euphorbia humistrata Engelm. (Spreading Sandmat)
  • Euphorbia hypericifolia L. (Graceful Sandmat)
  • Euphorbia ipecacuanhae L. (American Ipepac, Wild Ipepac)
  • Euphorbia lathyris L. (Caper Spurge, Mole Plant)
  • Euphorbia maculata L. (Spotted Spurge, Milk-purslane)
  • Euphorbia marginata Pursh (Snow-on-the-mountain)
  • Euphorbia mercurialina Michx. (Cumberland Spruge, Mercury Spurge)
  • Euphorbia nutans Lagasca y Segura (Nodding Spurge, Eyebane)
  • Euphorbia peplus L. (Petty Spruge)
  • Euphorbia polygonifolia L. (Seaside Spurge, Seaside Sandmat)
  • Euphorbia prostrata Aiton (Prostrate Sandmat)
  • Euphorbia pubentissima Michx. (False Flowering Spurge)
  • Euphorbia purpurea (Raf.) Fern. (Glade Spurge, Darlington Spurge, Purple Spurge)
  • Euphorbia serpens Kunth (Roundleaf Sandmat)
  • Euphorbia spathulata Lam. (Woodland Spurge)
  • Euphorbia vermiculata Raf. (Wormseed Sandmat, Hairy Spurge)
  • Euphorbia virgata Waldst. & Kitaib. (Wolf's-milk, Leafy Spurge)
  • Euphrasia stricta J. P. Wolff ex J. F. Lehmann var. stricta (Drug Eyebright)
  • Eurhynchiastrum pulchellum (Hedw.) Ignatov & Huttunen var. pulchellum (Rug Moss)
  • Eurybia chlorolepis (Burgess) Nesom (Mountain Wood Aster)
  • Eurybia compacta Nesom (Slender Aster)
  • Eurybia divaricata (L.) Nesom (White Wood Aster)
  • Eurybia macrophylla (L.) Cass. (Big-leaf Aster, Large-leaved Aster)
  • Eurybia radula (Ait.) Nesom (Low Rough Aster, Rough-leaved Aster)
  • Eurybia schreberi (Nees) Nees (Schreber's Aster)
  • Eurybia spectabilis (Ait.) Nesom (Showy Aster, Eastern Showy Aster)
  • Eurybia surculosa (Michx.) Nesom (Creeping Aster)
  • Euthamia caroliniana (L.) Greene ex Porter & Britt. (Slender Flat-top Goldenrod)
  • Euthamia floribunda Greene (Mid-Atlantic Flat-top Goldenrod)
  • Euthamia graminifolia (L.) Nutt. (Common Grass-leaved Goldenrod)
  • Euthamia lanceolata (L.) Nesom (Hairy Grass-leaved Goldenrod)
  • Euthamia weakleyi Nesom (Weakley’s Flat-top Goldentop)
  • Eutrochium dubium (Willd. ex Poir.) E.E. Lamont (Three-nerved Joe-pye-weed)
  • Eutrochium fistulosum (Barratt) E.E. Lamont (Hollow Joe-pye-weed)
  • Eutrochium maculatum (L.) E.E. Lamont var. maculatum (Spotted Joe-pye-weed)
  • Eutrochium purpureum (Linnaeus) E.E. Lamont var. purpureum (Sweet-scented Joe-pye-weed, Sweet Joe-pye-weed, Purple Joe-pye-weed)
  • Eutrochium steelei (E.E. Lamont) E.E. Lamont (Appalachian Joe-pye-weed, Steele's Joe-pye-weed)
  • Exochorda racemosa (Lindl.) Rehd. (Common Pearlbush)
  • Fabronia ciliaris (Brid.) Brid.
  • Facelis retusa (Lam.) Schultz-Bip. (Trampweed)
  • Fagopyrum esculentum Moench (Buckwheat)
  • Fagus grandifolia Ehrhart (American Beech)
  • Falcaria vulgaris Bernh. (Sickleweed)
  • Fallopia baldschuanica (Regel) Holub (Silver-lace Vine, China Fleece-vine)
  • Fallopia convolvulus (L.) A. Love (Bindweed, Black Bindweed)
  • Fallopia cristata (Engelm. & A. Gray) Holub (Crested False Buckwheat)
  • Fallopia scandens (L.) Holub (Climbing False Buckwheat)
  • Fatoua villosa (Thunb.) Nakai (Mulberry-weed, Hairy Crabweed)
  • Festuca filiformis Pourret (Hair Fescue, Fineleaf Sheep Fescue)
  • Festuca paradoxa Desv. (Cluster Fescue)
  • Festuca rubra L. (Red Fescue)
  • Festuca subverticillata (Pers.) Alexeev (Nodding Fescue)
  • Festuca trachyphylla (Hackell) Krajina (Hard Fescue)
  • Ficaria verna Hudson (Lesser Celandine)
  • Ficus carica L. (Common Fig)
  • Filago germanica (L.) Hudson (Common Cotton-rose, Common Cudweed)
  • Filipendula rubra (Hill) B.L. Robins. (Queen-of-the-Prairie)
  • Fimbristylis annua (Allioni) R. & S. (Annual Fimbry)
  • Fimbristylis autumnalis (L.) R. & S. (Slender Fimbry)
  • Fimbristylis caroliniana (Lam.) Fern. (Carolina Fimbry)
  • Fimbristylis castanea (Michx.) Vahl (Marsh Fimbry)
  • Fimbristylis littoralis Gaudichaud-Beaupr (Grasslike Fimbry, Lesser Fimbry)
  • Fimbristylis perpusilla Harper ex Small & Britt. (Harper's Fimbry)
  • Fimbristylis puberula (Michx.) Vahl (Hairy Fimbry)
  • Firmiana simplex (L.) W. Wight (Chinese Parasol Tree)
  • Fissidens adianthoides Hedwig
  • Fissidens bryoides Hedwig
  • Fissidens bushii (Cardot & Thr.) Cardot & Thr.
  • Fissidens closteri Austin ssp. closteri (Closter's Pocket Moss)
  • Fissidens dubius P. Beauv.
  • Fissidens elegans Brid.
  • Fissidens exilis Hedw.
  • Fissidens fontanus (Bach. Pyl.) Steud.
  • Fissidens grandifrons Brid.
  • Fissidens minutulus Sull.
  • Fissidens obtusifolius Wilson
  • Fissidens osmundioides Hedwig
  • Fissidens subbasilaris Hedwig
  • Fissidens taxifolius Hedwig
  • Flaveria trinervia (Spreng.) C. Mohr (Clustered Yellowtops)
  • Fleischmannia incarnata (Walt.) King & Robins. (Pink Thoroughwort)
  • Floerkea proserpinacoides Willd. (False Mermaid, False Mermaid-weed)
  • Foeniculum vulgare P. Mill. (Fennel, Sweet Fennel)
  • Fontinalis antipyretica Hedw.
  • Fontinalis dalecarlica Schimper
  • Fontinalis novae-angliae Sullivant
  • Fontinalis sphagnifolia (Mll. Hal.) Wijk & Margad.
  • Fontinalis sullivantii Lindb.
  • Forsstroemia producta (Hornsch.) Paris
  • Forsstroemia trichomitria (Hedw.) Lindb. (Fan Moss)
  • Forsythia suspensa (Thunb.) Vahl (Weeping Forsythia)
  • Forsythia viridissima Lindley (Green-stem Forsythia)
  • Fossombronia cristula Austin
  • Fossombronia foveolata Lindb.
  • Fossombronia porphyrorhiza (Nees) Prosk.
  • Fossombronia wondraczekii (Corda) Dumort. ex Lindb.
  • Fragaria vesca L. var americana Porter (Woodland Strawberry)
  • Fragaria virginiana Duchesne (Wild Strawberry)
  • Frangula alnus P. Mill. (Alder Buckthorn, Glossy Buckthorn)
  • Frangula caroliniana (Walter) A. Gray (Carolina Buckthorn)
  • Fraxinus americana L. (White Ash)
  • Fraxinus biltmoreana Beadle (Biltmore Ash, Biltmore White Ash)
  • Fraxinus caroliniana P. Miller (Carolina Ash, Water Ash, Pop Ash)
  • Fraxinus nigra Marshall (Black ash)
  • Fraxinus pennsylvanica Marshall (Green Ash, Red Ash)
  • Fraxinus profunda (Bush) Bush (Pumpkin Ash)
  • Fraxinus quadrangulata Michx. (Blue Ash)
  • Froelichia gracilis (Hook.) Moq. (Slender Cottonweed)
  • Frullania appalachiana R. M. Schuster
  • Frullania asagrayana Montagne
  • Frullania brittoniae A. Evans
  • Frullania caulisequa (Nees) Nees
  • Frullania eboracensis Gottsche ssp. eboracensis
  • Frullania eboracensis Gottsche ssp. virginica (Lehm.) R.M. Schust.
  • Frullania ericoides (Nees) Mont.
  • Frullania inflata Gottsche
  • Frullania kunzei Lehmann & Lindberg
  • Frullania oakesiana Sullivant ssp. oakesiana
  • Frullania plana Sullivant
  • Frullania riparia Hampe ex Lehm.
  • Fuirena breviseta (Coville) Coville (Short-bristled Umbrella-sedge)
  • Fuirena coerulescens Steudel (Blue Umbrella-sedge)
  • Fuirena pumila (Torrey) Sprengel (Dwarf Umbrella-sedge)
  • Fuirena squarrosa Michaux (Hairy Umbrella-sedge)
  • Fumaria muralis W.D.J. Koch ssp. muralis (Common Ramping-fumitory, Wall Fumitory)
  • Fumaria officinalis L. (Common Fumitory)
  • Funaria flavicans Michaux
  • Funaria hygrometrica Hedwig var. hygrometrica
  • Fuscocephaloziopsis catenulata (Huebener) Vana & Sderstr.
  • Fuscocephaloziopsis connivens (Dicks.) Vana & Sderstr.
  • Fuscocephaloziopsis lunulifolia (Dumort.) Vana & Sderstr.
  • Fuscocephaloziopsis macrostachya (Kaal.) Vana & Sderstr.
  • Gaillardia pulchella Foug. var. pulchella (Common Blanket-flower, Fire-wheel)
  • Galactia brachypoda Torrey & A. Gray (Sandhill Milkpea)
  • Galactia regularis (L.) B.S.P. (Eastern Milkpea)
  • Galactia volubilis (L.) Britt var. volubilis (Downy Milkpea)
  • Galanthus nivalis L. (Common Snowdrop)
  • Galax urceolata (Poir.) Brummitt (Galax)
  • Galearis spectabilis (L.) Raf. (Showy Orchis, Showy Orchid)
  • Galeopsis bifida Boenn. (Common Hemp-nettle, Split-lip Hemp-nettle)
  • Galinsoga parviflora Cav. var. parviflora (Small-flower Quickweed, Gallant Soldier)
  • Galinsoga quadriradiata Ruiz & Pavon (Fringed Quickweed, Hairy Galinsoga, Shaggy Soldier)
  • Galium anglicum Hudson (Lamarck's Bedstraw)
  • Galium aparine L. (Cleavers)
  • Galium asprellum Michx. (Rough Bedstraw)
  • Galium bermudense L. (Coastal Bedstraw)
  • Galium boreale L. (Northern Bedstraw)
  • Galium circaezans Michx. (Forest Bedstraw)
  • Galium concinnum Torr. & Gray (Shining Bedstraw)
  • Galium divaricatum Pourret ex Lam. (Lamarck's Bedstraw)
  • Galium lanceolatum Torr. (Lanceleaf Wild Licorice)
  • Galium latifolium Michx. (Purple Bedstraw)
  • Galium mollugo L. (Smooth Bedstraw, Hedge Bedstraw)
  • Galium obtusum Bigelow (Blunt-leaf Bedstraw)
  • Galium obtusum Bigelow var. filifolium (Wieg.) Fern. (Bluntleaf Bedstraw, Carolina Bedstraw)
  • Galium obtusum Bigelow var. obtusum (Bluntleaf Bedstraw)
  • Galium orizabense Hemsl. ssp. laevicaule (Weatherby & Blake) Dempster (Bald Bedstraw, Smooth-stem Bedstraw)
  • Galium pedemontanum (Bellardi) Allioni (Piedmont Bedstraw)
  • Galium pilosum Ait. (Hairy Bedstraw)
  • Galium sherardia E.H.L. Krause (Field Madder, Blue Field Madder)
  • Galium tinctorium L. (Three-lobed Bedstraw)
  • Galium triflorum Michx. (Sweet-scented Bedstraw)
  • Galium uniflorum Michx. (One-flowered Bedstraw)
  • Galium verum L. (Yellow Bedstraw)
  • Gamochaeta antillana (Urban) Anderb. (Delicate Everlasting)
  • Gamochaeta argyrinea Nesom (Silvery Everlasting, Silver Cudweed)
  • Gamochaeta calviceps (Fern.) Cabrera (Narrow-leaf Purple Everlasting)
  • Gamochaeta impatiens Nesom (Gray Everlasting)
  • Gamochaeta pensylvanica (Willd.) Cabrera (Pennsylvania Everlasting)
  • Gamochaeta purpurea (L.) Cabrera (Purple Cudweed, Purple Everlasting)
  • Gamochaeta simplicicaulis (Willd. ex Spreng.) Cabrera (Simple-stem Everlasting)
  • Gaultheria procumbens L. (Wintergreen, Teaberry)
  • Gaylussacia baccata (Wangenh.) K. Koch (Black Huckleberry)
  • Gaylussacia brachycera (Michx.) Gray (Box Huckleberry)
  • Gaylussacia dumosa (Andr.) Torr. & Gray (Dwarf Huckleberry)
  • Gaylussacia frondosa (L.) Torr. & Gray ex Torr. (Dangleberry)
  • Gelsemium sempervirens (L.) St.-Hilaire (Yellow Jessamine, Carolina Jessamine)
  • Gemmabryum caespiticium (Hedw.) J.R. Spence
  • Gemmabryum dichotomum (Hedw.) J.R. Spence & H.P. Ramsay
  • Gemmabryum subapiculatum (Hampe) J.R. Spence & H.P. Ramsay
  • Gentiana austromontana Pringle & Sharp (Appalachian Gentian)
  • Gentiana autumnalis L. (Pine Barren Gentian)
  • Gentiana catesbaei Walt. (Coastal Plain Gentian, Elliott's Gentian)
  • Gentiana clausa Raf. (Bottle Gentian, Closed Gentian)
  • Gentiana decora Pollard (Showy Gentian)
  • Gentiana linearis Froel. (Narrowleaf Gentian)
  • Gentiana saponaria L. (Soapwort Gentian)
  • Gentiana villosa L. (Striped Gentian)
  • Gentianella occidentalis (A. Gray) Small (Western Stiff Gentian)
  • Gentianella quinquefolia (L.) Small (Eastern Stiff Gentian)
  • Gentianopsis crinita (Froel.) Ma (Greater Fringed Gentian)
  • Geocalyx graveolens (Schrad.) Nees
  • Geocarpon carolinianum (Walt.) E.E. Schilling (Carolina Sandwort, Pine-barren Sandwort)
  • Geocarpon glabrum (Michx.) E.E. Schilling (Appalachian Sandwort)
  • Geocarpon groenlandicum (Retzius) E.E. Schilling (Mountain Sandwort, Greenland Sandwort)
  • Geranium carolinianum L. (Carolina Geranium, Carolina Cranesbill)
  • Geranium columbinum L. (Long-stalk Cranesbill)
  • Geranium dissectum L. (Cut-leaf Geranium, Cut-leaf Cranesbill)
  • Geranium maculatum L. (Wild Geranium)
  • Geranium molle L. (Dove's-foot Geranium, Dove's-foot Cranesbill)
  • Geranium pusillum L. (Small Geranium, Small-flowered Cranesbill)
  • Geranium robertianum L. (Herb Robert)
  • Geranium sibiricum L. (Siberian Geranium, Siberian Cranesbill)
  • Geranium thunbergii Sieb. & Zucc. ex Lindl. & Paxton (Thunberg's Geranium)
  • Geum aleppicum Jacquin (Yellow Avens)
  • Geum canadense Jacquin (White Avens)
  • Geum geniculatum Michaux (Bent Avens)
  • Geum laciniatum Murray (Rough Avens)
  • Geum vernum (Raf.) Torr. & Gray (Spring Avens)
  • Geum virginianum L. (Cream Avens)
  • Gillenia stipulata (Muhl. ex Willd.) Nutt. (American Ipecac, Western Indian-physic)
  • Gillenia trifoliata (L.) Moench (Bowman's-root, Mountain Indian-physic)
  • Glandularia canadensis (L.) Nutt. (Rose Vervain, Rose Verbena, Creeping Vervain)
  • Glaucium flavum Crantz (Yellow Horned-poppy, Sea-poppy)
  • Glechoma hederacea L. (Gill-over-the-ground, Ground-ivy)
  • Gleditsia triacanthos L. (Honey Locust)
  • Glyceria acutiflora Torr. (Sharp-scaled Mannagrass, Creeping Mannagrass)
  • Glyceria canadensis (Michx.) Trin. (Canada Mannagrass, Rattlesnake Mannagrass)
  • Glyceria grandis S. Wats. var. grandis (American Mannagrass)
  • Glyceria laxa (Scribn.) Scribn. (Northern Mannagrass, Lax Mannagrass)
  • Glyceria melicaria (Michx.) F.T. Hubbard (Slender Mannagrass, Melic Mannagrass)
  • Glyceria obtusa (Muhl.) Trin. (Coastal Mannagrass)
  • Glyceria septentrionalis A.S. Hitchc. (Eastern Mannagrass, Floating Mannagrass)
  • Glyceria striata (Lam.) A.S. Hitchc. var. striata (Fowl Mannagrass)
  • Glycine max (L.) Merr. (Soybean)
  • Glycyrrhiza lepidota Pursh (Wild Licorice, American Licorice)
  • Gnaphalium uliginosum L. (Low Cudweed)
  • Gomphrena serrata L. (Arrasa con todo)
  • Gonolobus suberosus (L.) R. Br. var. suberosus (Eastern Anglepod, Angular-fruit Milkvine)
  • Goodyera pubescens (Willd.) R.Br. ex Aiton f. (Downy Rattlesnake-plantain)
  • Goodyera repens (L.) R.Br. in W. Aiton & W.T. Aiton (Dwarf Rattlesnake-plantain, Lesser Rattlesnake-plantain)
  • Gratiola neglecta Torr. (Clammy Hedge-hyssop)
  • Gratiola ramosa Walter (Branched Hedge-hyssop)
  • Gratiola virginiana L. var. aestuariorum Pennell (Estuarine Hedge-hyssop)
  • Gratiola virginiana L. var. virginiana (Round-fruit Hedge-hyssop)
  • Gratiola viscidula Pennell (Short's Hedge-hyssop)
  • Greeneochloa coarctata (Eaton) P.M. Peterson, Soreng, Romasch. & Barber (Nuttall's Reedgrass)
  • Grewia biloba G. Don (Bilobed Grewia)
  • Grimmia donniana Sm.
  • Grimmia hartmanii Schimp.
  • Grimmia laevigata (Bridel) Bridel
  • Grimmia longirostris Hook.
  • Grimmia olneyi Sull.
  • Grimmia ovalis (Hedwig) Lindberg
  • Grimmia pilifera Palisot de Beauvois
  • Grimmia pulvinata (Hedw.) Sm.
  • Grimmia teretinervis Limpr.
  • Grindelia lanceolata Nutt. (Narrowleaf Gumweed)
  • Grindelia squarrosa (Pursh) Dunal var. squarrosa (Curly-top Gumweed, Curly-cup Gumweed)
  • Guizotia abyssinica (L. f.) Cass. (Niger-seed, Niger-thistle)
  • Gymnocarpium appalachianum Pryer and Haufler (Appalachian Oak Fern)
  • Gymnocladus dioicus (L.) K. Koch (Kentucky Coffee-tree)
  • Gymnopogon ambiguus (Michx.) B.S.P. (Eastern Beard Grass)
  • Gymnopogon brevifolius Trin. (Short-leaf Beard Grass)
  • Gymnostomum aeruginosum J.E. Smith
  • Habenaria repens Nuttall (Water-spider Orchid, Floating Orchid)
  • Hackelia virginiana (L.) I.M.Johnston (Virginia Stickseed)
  • Hageniella micans (Mitt.) B. C. Tan & Y. Jia
  • Halesia tetraptera Ellis (Silverbell, Common Silverbell)
  • Hamamelis virginiana L. var. virginiana (Witch Hazel)
  • Haplocladium microphyllum (Hedw.) Broth.
  • Haplocladium virginianum (Brid.) Broth.
  • Harpalejeunea molleri (Steph.) Grolle ssp. integra (R. M. Schust.) Damsh.
  • Harpanthus scutatus (F. Weber & D. Mohr) Spruce
  • Harperella nodosa Rose (Harperella)
  • Hasteola suaveolens (L.) Pojarkova (Sweet-scented Indian-plantain)
  • Hedeoma hispida Pursh (Rough Pennyroyal)
  • Hedeoma pulegioides (L.) Pers. (American Pennyroyal)
  • Hedera helix L. (English Ivy, Common Ivy)
  • Hedera hibernica (G. Kirchner) Bean (Irish Ivy)
  • Hedwigia ciliata (Hedw.) P. Beauv. (Medusa Moss)
  • Helanthium tenellum (Martius) Britton (Dwarf Burhead)
  • Helenium amarum (Raf.) H. Rock var. amarum (Bitterweed)
  • Helenium autumnale L. (Common Sneezeweed, Autumn Sneezeweed)
  • Helenium brevifolium (Nutt.) Wood (Short-leaf Sneezeweed)
  • Helenium flexuosum Raf. (Southern Sneezeweed)
  • Helenium virginicum Blake (Virginia Sneezeweed)
  • Helianthus angustifolius L. (Narrow-leaved Sunflower)
  • Helianthus annuus L. (Common Sunflower)
  • Helianthus atrorubens L. (Purple-disk Sunflower)
  • Helianthus debilis Nutt. ssp. cucumerifolius (Torr. & Gray) Heiser (Cucumber-leaf Sunflower)
  • Helianthus decapetalus L. (Thin-leaved Sunflower)
  • Helianthus divaricatus L. (Woodland Sunflower)
  • Helianthus giganteus L. (Tall Sunflower, Giant Sunflower)
  • Helianthus grosseserratus Martens (Sawtooth Sunflower)
  • Helianthus hirsutus Raf. (Hairy Sunflower, Stiff-hair Sunflower)
  • Helianthus laetiflorus Pers. (Showy Sunflower)
  • Helianthus laevigatus Torr. & Gray (Smooth Sunflower)
  • Helianthus maximiliani Schrad. (Maximilian Sunflower)
  • Helianthus microcephalus Torr. & Gray (Small-headed Sunflower)
  • Helianthus mollis Lam. (Ashy Sunflower)
  • Helianthus occidentalis Riddell ssp. occidentalis (Western Sunflower)
  • Helianthus pauciflorus Nutt. ssp. pauciflorus (Stiff Sunflower)
  • Helianthus petiolaris Nutt. ssp. petiolaris (Plains Sunflower)
  • Helianthus strumosus L. (Pale-leaved Sunflower)
  • Helianthus tuberosus L. (Jerusalem Artichoke)
  • Helianthus verticillatus Small (Whorled Sunflower)
  • Heliopsis helianthoides (L.) Sweet var. helianthoides (Oxeye, Smooth Oxeye)
  • Heliotropium amplexicaule Vahl (Clasping Heliotrope, Wild Heliotrope)
  • Heliotropium curassavicum L. var. curassavicum (Seaside Heliotrope)
  • Heliotropium europaeum L. (European Heliotrope)
  • Heliotropium indicum L. (Indian Heliotrope)
  • Helleborus orientalis Lam. (Lenten-rose)
  • Helleborus viridis L. (Green Hellebore, Christmas-rose, Lenten-rose)
  • Helonias bullata L. (Swamp-pink)
  • Hemerocallis fulva (L.) L. (Orange Day-lily, Tiger-lily)
  • Hepatica acutiloba DC. (Sharp-lobed Hepatica, Sharp-lobed Liverleaf)
  • Hepatica americana (DC.) Ker-Gawl. (Round-lobed Hepatica, Round-lobed Liverleaf)
  • Heracleum maximum Bartr. (Cow-parsnip, Common Cow-parsnip)
  • Herbertus tenuis (A. Evans) H.A. Mill. & E.B. Bohrer
  • Herpetineuron toccoae (Sull. & Lesq.) Cardot
  • Herzogiella striatella (Brid.) Z. Iwats.
  • Herzogiella turfacea (Lindb.) Z. Iwats.
  • Hesperis matronalis Linnaeus (Dame's Rocket)
  • Heteranthera dubia (Jacquin) MacMillan (Water Stargrass)
  • Heteranthera pauciflora C.N. Horn (Atlantic Mud Plantain)
  • Heteranthera reniformis Ruiz & Pavon (Mud Plantain, Kidneyleaf Mud Plantain)
  • Heterocladium macounii Best
  • Heterophyllium affine (Hook.) M. Fleisch.
  • Heterotheca camporum (Greene) Shinners var. glandulissima Semple (Nashville Camphorweed)
  • Heterotheca subaxillaris (Lam.) Britt. & Rusby (Camphorweed, Dune Camphorweed)
  • Heuchera alba Rydb. (White Alumroot)
  • Heuchera americana L. (Alumroot, Americana Alumroot)
  • Heuchera caroliniana (Rosendahl, Butters, & Lakela) Wells (Carolina Alumroot)
  • Heuchera hispida Pursh (Purple Alumroot)
  • Heuchera longiflora Rydb. (Long-flowered Alumroot)
  • Heuchera parviflora Bartling var. parviflora (Small-flowered Alumroot)
  • Heuchera pubescens Pursh (Marbled Alumroot)
  • Heuchera villosa Michaux (Hairy Alumroot)
  • Hexalectris spicata (Walter) Barnh. (Crested Coralroot)
  • Hexasepalum radula (Willd.) Delprete & J.H. Kirkbride (Rough Buttonweed)
  • Hexasepalum teres (Walter) J.H. Kirkbride (Common Buttonweed, Rough Buttonweed)
  • Hexastylis arifolia (Michx.) Small (Little Brown Jug, Arrowleaf Heartleaf)
  • Hexastylis chueyi (B.T. Sinn) Weakley & D.B. Poind. (Chuey's Evergreen Wild Ginger)
  • Hexastylis contracta Blomquist (Mountain Heartleaf)
  • Hexastylis heterophylla (Ashe) Small (Variable-leaf Heartleaf)
  • Hexastylis lewisii (Fern.) Blomquist & Oosting (Lewis's Heartleaf)
  • Hexastylis minor (Ashe) Blomquist (Little Heartleaf)
  • Hexastylis ruthii (Ashe) Small (Appalachian Little Brown Jug)
  • Hexastylis sorriei Gaddy (Sandhill Heartleaf)
  • Hexastylis virginica (L.) Small (Virginia Heartleaf)
  • Hibiscus aculeatus Walter (Savanna Hibiscus)
  • Hibiscus coccineus Walt. (Scarlet Rose-mallow)
  • Hibiscus laevis Allioni (Halberd-leaf Rose-mallow, Smooth Rose-mallow)
  • Hibiscus moscheutos L. (Swamp Rose-mallow, Eastern Rose-mallow, Crimson-eyed Rose-mallow)
  • Hibiscus syriacus L. (Rose-of-Sharon, Althaea)
  • Hibiscus trionum L. (Flower-of-an-hour)
  • Hieracium gronovii L. (Hairy Hawkweed)
  • Hieracium paniculatum L. (Panicled Hawkweed, Alleghany Hawkweed)
  • Hieracium scabrum Michx. (Rough Hawkweed)
  • Hieracium traillii Greene (Maryland Hawkweed)
  • Hieracium venosum L. (Rattlesnake Weed)
  • Hierochloe hirta (Schrank) Borbs (Holy Grass, Sweet Grass, Vanilla Grass)
  • Holcus lanatus L. (Common Velvet Grass)
  • Holosteum umbellatum L. ssp. umbellatum (Jagged Chickweed)
  • Homalia trichomanoides (Hedw.) Schimp. var. trichomanoides
  • Homaliadelphus sharpii (R. S. Williams) Sharp
  • Homalosorus pycnocarpos (Spreng.) Pichi-Sermolli (Glade Fern)
  • Homalotheciella subcapillata (Hedw.) Broth.
  • Homomallium adnatum (Hedw.) Broth.
  • Honckenya peploides (L.) Ehrh. ssp. robusta (Fern.) Hulten (Sea-beach Sandwort, Sea Sandwort)
  • Hookeria acutifolia Hooker & Greville
  • Hordeum jubatum L. ssp. jubatum (Foxtail Barley)
  • Hordeum murinum L. (Wall Barley, False Barley)
  • Hordeum pusillum Nutt. (Little Barley)
  • Hordeum vulgare L. (Barley)
  • Hosta ventricosa (Salisb.) Stearn (Blue Plantain-lily)
  • Hottonia inflata Ell. (Featherfoil, Water-violet)
  • Houstonia caerulea L. (Common Bluets, Azur Bluets, Quaker Ladies)
  • Houstonia canadensis Willd. ex Roemer & J.A. Schultes (Canada Bluets)
  • Houstonia longifolia Gaertn. (Longleaf Bluets)
  • Houstonia micrantha (Shinners) Terrell (Small-anthered Bluet)
  • Houstonia montana Small (Roan Mountain Bluets)
  • Houstonia nigricans (Lamarck) Fernald var. nigricans (Glade Bluets, Diamond-flowers)
  • Houstonia purpurea L. (Summer Bluets)
  • Houstonia pusilla Schoepf (Tiny Bluets)
  • Houstonia serpyllifolia Michx. (Thyme-leaf Bluets)
  • Houstonia tenuifolia Nuttall (Narrowleaf Bluets, Diffuse-branched Bluets)
  • Houttuynia cordata Thunb. (Chameleon Plant, Bishop's Weed)
  • Hudsonia tomentosa Nutt. (Sand Heather, Woolly Beach Heather)
  • Humulus japonicus Sieb. & Zucc. (Japanese Hops)
  • Humulus lupulus L. (Common Hops)
  • Huperzia appressa (Desv.) A.& D. Love (Appalachian Fir Clubmoss, Appalachian Clubmoss, Appalachian Firmoss)
  • Huperzia appressa lucidula
  • Huperzia lucidula (Michx.) Trevisan (Shining Clubmoss, Shining Firmoss)
  • Huperzia porophila (Lloyd & Underwood) Holub (Rock Clubmoss)
  • Huperzia porophila lucidula
  • Hyacinthoides hispanica (P. Mill.) Rothm. (Spanish Bluebell)
  • Hyacinthoides nonscripta (L.) Chouard ex Rothm. (English Bluebell)
  • Hyacinthus orientalis L. (Garden Hyacinth)
  • Hydrangea arborescens L. (Wild Hydrangea, Smooth Hydrangea)
  • Hydrangea barbara (L.) B. Schulz (Climbing Hydrangea, Woodvamp)
  • Hydrastis canadensis L. (Golden-seal)
  • Hydrilla verticillata (L.f.) Royle (Hydrilla)
  • Hydrocotyle americana L. (American Water-pennywort, American Marsh-pennywort)
  • Hydrocotyle bonariensis Lam. (Coastal Water-pennywort, Dune Water-pennywort, Large-leaf Pennywort)
  • Hydrocotyle prolifera Kellogg (Whorled Marsh-pennywort)
  • Hydrocotyle ranunculoides L. f. (Swamp Water-pennywort, Floating Marsh-pennywort)
  • Hydrocotyle sibthorpioides Lam. (Lawn Water-pennywort)
  • Hydrocotyle umbellata L. (Marsh Water-pennywort, Marsh-pennywort)
  • Hydrocotyle verticillata Thunb. (Whorled Marsh-pennywort)
  • Hydrolea quadrivalvis Walt. (Waterpod)
  • Hydrophyllum canadense L. (Canada Waterleaf)
  • Hydrophyllum macrophyllum Nutt. (Large-leaf Waterleaf, Hairy Waterleaf)
  • Hydrophyllum virginianum L. var. atranthum (E.J. Alexander) Constance (Appalachian Waterleaf)
  • Hydrophyllum virginianum L. var. virginianum (Virginia Waterleaf, Eastern Waterleaf)
  • Hygroamblystegium varium (Hedw.) Mnkemeyer ssp. noterophilum (Sull. & Lesq.) Vanderporten & Hedens
  • Hygroamblystegium varium (Hedw.) Mnkemeyer ssp. varium var. humile (P. Beauv.) Vanderpoorten & Hedens
  • Hygroamblystegium varium (Hedw.) Mnkemeyer ssp. varium var. varium (Tangled Thread Moss)
  • Hygrohypnum duriusculum (De Not.) D.W. Jamieson (Ruffled Brook Moss)
  • Hygrohypnum eugyrium (Schimp.) Loeske (Swollen Brook Moss)
  • Hygrohypnum luridum (hedw.) Jenn. (Stiff Brook Moss)
  • Hygrohypnum molle (Hedw.) Loeske
  • Hygrohypnum ochraceum (Turner ex Wilson) Loeske
  • Hylocomiastrum umbratum (Hedw.) M. Fleisch. ex Broth.
  • Hylocomium splendens (Hedw.) Schimp. (Stairstep Moss)
  • Hylodesmum glutinosum (Muhl. ex Willld.) H. Ohashi & R.R. Mill (Pointed-leaf Tick-trefoil)
  • Hylodesmum nudiflorum (L.) H. Ohashi & R.R. Mill (Naked-Flowered Tick-trefoil)
  • Hylodesmum pauciflorum (Nutt.) H. Ohashi & R.R. Mill (Few-flowered Tick-trefoil)
  • Hylotelephium erythrostictum (Miq.) H. Ohba (Garden Stonecrop, Garden Orpine)
  • Hylotelephium telephioides (Michx.) H. Ohba (Allegheny Stonecrop, Allegheny Live-for-ever)
  • Hylotelephium telephium (L.) H. Ohba (Live-for-ever)
  • Hymenostylium recurvirostrum (Hedw.) Dixon var. recurvirostrum
  • Hyophila involuta (Hook.) A. Jaeger
  • Hypericum adpressum Raf. ex Barton (Bog St. John's-wort, Creeping St. John's-wort)
  • Hypericum boreale (Britt.) Bickn. (Northern St. John's-wort)
  • Hypericum canadense L. (Canada St. John's-wort)
  • Hypericum crux-andreae (L.) Crantz (St. Peter's-wort)
  • Hypericum densiflorum Pursh (Bushy St. John's-wort)
  • Hypericum denticulatum Walt. (Coppery St. John's-wort)
  • Hypericum drummondii (Grev. & Hooker) Torrey & A. Gray (Nits-and-lice, Drummond's St. John's-wort)
  • Hypericum ellipticum Hooker (Pale St. John's-wort)
  • Hypericum frondosum Michx. (Golden St. John's-wort, Cedar Glade St. John's-wort)
  • Hypericum galioides Lamarck (Bedstraw St. John's-wort)
  • Hypericum gentianoides (L.) B.S.P. (Pineweed, Orange-grass)
  • Hypericum gymnanthum Engelm. & A. Gray (Clasping St. John's-wort, Clasping-leaf St. John's-wort)
  • Hypericum hypericoides (L.) Crantz (St. Andrew's Cross)
  • Hypericum interior Small (Interior Bushy St. John's-wort)
  • Hypericum lloydii (Svenson) P. Adams (Sandhill St. John's-wort, Lloyd's St. John's-wort)
  • Hypericum mitchellianum Rydb. (Blue Ridge St. John's-wort)
  • Hypericum mutilum L. (Dwarf St. John's-wort)
  • Hypericum nudiflorum Michx. ex Willd. (Early St. John's-wort)
  • Hypericum perforatum L. (Common St. John's-wort)
  • Hypericum prolificum L. (Shrubby St. John's-wort)
  • Hypericum punctatum Lam. (Spotted St. John's-wort)
  • Hypericum setosum L. (Hairy St. John's-wort)
  • Hypericum stragulum P. Adams & Robson (Low St. Andrew's Cross)
  • Hypericum virgatum Lam. (Sharp-leaf St. John's-wort)
  • Hypnum cupressiforme Hedw. var. cupressiforme
  • Hypnum cupressiforme var. filiforme Brid.
  • Hypnum curvifolium Hedwig (Greater Plait Moss)
  • Hypnum fauriei Cardot (Plait Moss)
  • Hypnum imponens Hedwig (Brocade Moss)
  • Hypnum lindbergii Mitt. (Pale Plait Moss)
  • Hypnum pallescens (Hedw.) P. Beauv. (Lesser Plait Moss)
  • Hypnum pratense Koch ex Spruce
  • Hypochaeris radicata L. (Spotted Cat's-ear)
  • Hypopitys monotropa Crantz (Pinesap)
  • Hypoxis curtisii Rose (Curtiss' Yellow Stargrass, Swamp Stargrass)
  • Hypoxis hirsuta (L.) Coville (Eastern Yellow Stargrass)
  • Hypoxis sessilis L. (Glossy-seed Yellow Stargrass)
  • Hypoxis wrightii (Baker) Brackett (Bristle-seed Yellow Stargrass, Wright's Stargrass)
  • Hyptis mutabilis (A. Rich.) Briq. (Tropical Bushmint)
  • Iberis amara Linnaeus (Annual Candytuft)
  • Ilex aquifolium L. (English Holly)
  • Ilex collina Alexander (Long-stalked Holly)
  • Ilex coriacea (Pursh) chapman (Sweet Gallberry, Big Gallberry)
  • Ilex cornuta Lindley (Chinese Holly, Burford Holly)
  • Ilex crenata Thunberg (Japanese Holly)
  • Ilex decidua Walt. (Deciduous Holly, Possum-haw)
  • Ilex glabra (L.) Gray (Inkberry)
  • Ilex laevigata (Pursh) Gray (Smooth Winterberry)
  • Ilex montana Torr. & Gray ex Gray (Mountain Holly)
  • Ilex opaca Aiton var. opaca (American Holly)
  • Ilex verticillata (L.) Gray (Winterberry)
  • Ilex vomitoria Aiton (Yaupon)
  • Iliamna corei Sherff (Peter's Mountain Mallow)
  • Iliamna remota Greene (Kankakee Mallow, Kankakee Globe-mallow)
  • Imbribryum gemmiparum ((De. Not.) J.R. Spence & H.P. Ramsay
  • Impatiens balsamina L. (Garden Balsam)
  • Impatiens capensis Meerburg (Orange Jewelweed, Spotted Jewelweed)
  • Impatiens pallida Nuttall (Yellow Jewelweed, Pale Jewelweed)
  • Imperata cylindrica (L.) Beauv. (Cogongrass, Brazilian Satintail)
  • Inula helenium L. (Elecampane)
  • Ionactis linariifolia (L.) Greene (Stiff-leaved Aster)
  • Ipomoea coccinea L. (Red Morning Glory, Scarlet Creeper)
  • Ipomoea hederacea Jacq. (Ivy-leaf Morning Glory)
  • Ipomoea lacunosa L. (Small White Morning Glory)
  • Ipomoea pandurata (L.) G.F.W. Mey. (Wild Potato-vine, Manroot, Man-of-the-earth)
  • Ipomoea purpurea (L.) Roth (Common Morning Glory)
  • Ipomoea quamoclit L. (Cypress-vine)
  • Ipomoea triloba L. (Little-bell)
  • Ipomopsis rubra (L.) Wherry (Standing-cypress)
  • Iresine rhizomatosa Standley (Eastern Bloodleaf, Juda's Bush)
  • Iris cristata Solander ex Aiton (Dwarf Crested Iris)
  • Iris domestica (Linnaeus) Goldblatt & Mabberley (Blackberry-lily)
  • Iris germanica L. (German Iris)
  • Iris prismatica Pursh (Slender Blue Iris, Slender Blue Flag)
  • Iris pseudacorus L. (Yellow Iris, Yellow Flag)
  • Iris sibirica L. (Sibirian Iris)
  • Iris verna L. (Dwarf Iris)
  • Iris verna L. var. smalliana Fernald ex M.E. Edwards (Upland Dwarf Iris)
  • Iris verna L. var. verna (Coastal Plain Dwarf Iris)
  • Iris versicolor L. (Larger Blue Flag, Northern Blue Flag)
  • Iris virginica L. (Virginia Blue Flag, Southern Blue Flag)
  • Isatis tinctoria Linnaeus (Dyer's Woad)
  • Isoetes appalachiana Brunton and Britton (Appalachian Quillwort)
  • Isoetes engelmannii A. Braun (Engelmann's Quillwort)
  • Isoetes hyemalis Brunton (Winter Quillwort)
  • Isoetes lacustris L. (Lake Quillwort)
  • Isoetes mattaponica Musselman & W.C. Taylor (Mattaponi Quillwort)
  • Isoetes melanopoda Gay & Durieu ssp. silvatica Brunton & Britton (Black-footed Quillwort)
  • Isoetes piedmontana (N.E. Pfeiffer) C.F. Reed (Piedmont Quillwort)
  • Isoetes riparia Engelm. ex A. Braun (Shore Quillwort)
  • Isoetes valida (Engelm.) Clute (Mountain Quillwort)
  • Isoetes virginica N.E. Pfeiffer (Virginia Quillwort)
  • Isoetes altonharvillii Musselman & Bray
  • Isoetes bruntonii Knepper & Musselman
  • Isoetes carltaylori Musselman
  • Isoetes fairbrothersii Montgomery & Taylor?
  • Isolepis carinata Hook. & Arnott ex Torr. (Keeled Bulrush)
  • Isolepis hystrix (Thunb.) Nees (Bottlebrush Bulrush)
  • Isopaches bicrenatus (Schmidel ex Hoffm.) H. Buch var. bicrenatus
  • Isopterygiopsis muelleriana (Schimp.) Z. Iwats.
  • Isopterygiopsis pulchella (Hedw.) Z. Iwats.
  • Isopterygium tenerum (Sw.) Mitt.
  • Isothecium myosuroides Brid.
  • Isotrema macrophyllum (Lam.) C.F. Reed (Dutchman's-pipe, Pipevine)
  • Isotria medeoloides (Pursh) Raf. (Small Whorled Pogonia)
  • Isotria verticillata (Muhl. ex Willd.) Raf. (Large Whorled Pogonia)
  • Itea virginica L. (Virginia-willow, Virginia Sweetspire)
  • Iva annua L. (Annual Marsh-elder, Sumpweed)
  • Iva frutescens L. (Marsh-elder)
  • Iva imbricata Walt. (Dune Marsh-elder, Seaside Marsh-elder)
  • Jacquemontia tamnifolia (L.) Griseb. (Common Jacquemontia)
  • Jeffersonia diphylla (L.) Pers. (Twinleaf)
  • Jubula pennsylvanica (Stephani) A. Evans ssp. pennsylvanica
  • Juglans cinerea L. (Butternut, White Walnut)
  • Juglans nigra L. (Black Walnut)
  • Juncus acuminatus Michx. (Sharp-fruited Rush)
  • Juncus anthelatus (Wieg.) R.E. Brooks (Large Path Rush, Greater Poverty Rush)
  • Juncus articulatus L. (Jointed Rush)
  • Juncus balticus Willd. var. littoralis Engelm. (Baltic Rush)
  • Juncus biflorus Ell. (Large Grass-leaved Rush)
  • Juncus brachycarpus Engelm. (Short-fruited Rush)
  • Juncus brachycephalus (Engelm.) Buch. (Small-headed Rush)
  • Juncus bufonius L. (Toad Rush)
  • Juncus caesariensis Coville (New Jersey Rush)
  • Juncus canadensis J. Gay ex Laharpe (Canadian Rush)
  • Juncus coriaceus Mackenzie (Leathery Rush)
  • Juncus debilis Gray (Weak Rush)
  • Juncus dichotomus Ell. (Forked Rush)
  • Juncus diffusissimus Buckl. (Diffuse Rush, Slim-pod Rush)
  • Juncus dudleyi Wieg. (Dudley's Rush)
  • Juncus effusus L. var. pylaei (Laharpe) Fernald & Wiegand (Soft Rush)
  • Juncus effusus L. var. solutus Fernald & Wiegand (Common Rush, Soft Rush)
  • Juncus elliottii Chapman (Bog Rush, Elliott's Rush)
  • Juncus gerardii Loisel. (Saltmarsh Rush, Blackfoot Rush, Blackgrass)
  • Juncus inflexus L. (European Meadow Rush)
  • Juncus longii Fern. (Long's Rush)
  • Juncus marginatus Rostk. (Grass-leaved Rush)
  • Juncus megacephalus M.A. Curtis (Big-headed Rush)
  • Juncus nodosus L. (Knotted Rush)
  • Juncus pelocarpus E. Mey. (Brown-fruited Rush)
  • Juncus repens Michaux (Creeping Rush)
  • Juncus roemerianus Scheele (Black Needle Rush)
  • Juncus scirpoides Lam. var. compositus Harper (Lobe-headed Rush)
  • Juncus scirpoides Lam. var. scirpoides (Needle-pod Rush, Lobe-headed Rush)
  • Juncus secundus Beauv. ex Poir. (Secund Rush, Lopsided Rush)
  • Juncus subcaudatus (Engelm.) Coville & Blake (Short-tailed Rush)
  • Juncus tenuis Willd. (Path Rush, Slender Rush, Poverty Rush)
  • Juncus torreyi Coville (Torrey's Rush)
  • Juncus tweedyi Rydberg (Narrow-panicled Rush)
  • Juncus validus Coville var. validus (Round-headed Rush)
  • Jungermannia pumila With.
  • Juniperus communis L. var. communis (European Common Juniper)
  • Juniperus communis L. var. depressa Pursh (Ground Juniper, Mountain Juniper)
  • Juniperus virginiana L. var. virginiana (Eastern Redcedar)
  • Justicia americana (L.)Vahl (Common Water-willow, American Water-willow)
  • Justicia ovata (Walter) Lindau var. ovata (Coastal Plain Water-willow, Loose-flower Water-willow)
  • Kalmia angustifolia L. (Sheep Laurel, Sheepkill)
  • Kalmia carolina Small (Carolina Laurel, Carolina Wicky, Carolina Bog-myrtle)
  • Kalmia latifolia L. (Mountain Laurel, Ivy)
  • Kalopanax septemlobus (Thunb. ex A. Murr.) Koidz. (Castor Aralia, Prickly Castor Oil Tree)
  • Kellochloa verrucosa (Muhl.) Lizarazu, M.V. Nicola, & Scataglini (Warty Panic Grass)
  • Kerria japonica (L.) DC. (Japanese-rose)
  • Kickxia elatine (L.) Dumort. (Sharp-leaf Cancerwort)
  • Koeleria spicata (Linnaeus) Barber, Quintanar, Soreng, & P.M. Peterson ssp. spicata (Narrow False Oats, Alpine Oatgrass, Spike Trisetum)
  • Koelreuteria paniculata Laxmann (Golden Rain Tree)
  • Kolkwitzia amabilis Graebner (Beautybush)
  • Kosteletzkya pentacarpos (L.) Ledebour (Seashore Mallow, Salt Marsh Mallow)
  • Krigia biflora (Walt.) Blake var. biflora (Two-flowered Dwarf-dandelion, Two-flowered Cynthia)
  • Krigia cespitosa (Raf.) Chambers (Weedy Dwarf-dandelion)
  • Krigia dandelion (L.) Nutt. (Potato Dwarf-dandelion)
  • Krigia virginica (L.) Willd. (Dwarf-dandelion, Virginia Dwarf-dandelion)
  • Kummerowia stipulacea (Maxim.) Makino (Korean-clover)
  • Kummerowia striata (Thunb.) Schindl. (Japanese-clover)
  • Kurzia sylvatica (A. Evans) Grolle
  • Lablab purpureus (L.) Sweet (Hyacinth-bean)
  • Lachnanthes caroliniana (Lam.) Dandy (Redroot)
  • Lachnocaulon anceps (Walt.) Morong (Common Bog-buttons)
  • Lactuca biennis (Moench) Fern. (Tall Blue Lettuce)
  • Lactuca canadensis L. (Wild Lettuce)
  • Lactuca floridana (L.) Gaertn. (Florida Blue Lettuce, Woodland Lettuce)
  • Lactuca graminifolia Michx. var. graminifolia (Grass-leaf Lettuce)
  • Lactuca hirsuta Muhl. ex Nutt. (Hairy Lettuce)
  • Lactuca saligna L. (Willow-leaf Lettuce)
  • Lactuca serriola L. (Prickly Lettuce)
  • Lagerstroemia indica L. (Crepe-myrtle)
  • Lamium amplexicaule L. var. amplexicaule (Henbit, Henbit Dead-nettle)
  • Lamium dissectum With. (Cutleaf Dead-nettle)
  • Lamium galeobdolon (L.) L. (Yellow Archangel)
  • Lamium maculatum L. (Spotted Dead-nettle)
  • Lamium purpureum L. (Red Dead-nettle, Purple Dead-nettle)
  • Landoltia punctata (G. Mey.) D.H. Les & D.J. Crawford (Lesser Greater Duckweed)
  • Laportea canadensis (L.) Weddell (Wood Nettle)
  • Lapsana communis L. (Common Nipplewort)
  • Lathyrus hirsutus L. (Caley Pea, Singletary Pea)
  • Lathyrus latifolius L. (Everlasting Pea, Perennial Sweet Pea)
  • Lathyrus palustris L. (Marsh Pea, Marsh Vetchling)
  • Lathyrus pusillus Ell. (Tiny Pea, Small Vetchling)
  • Lathyrus venosus Muhl. ex Willd. var. venosus (Veiny Pea)
  • Lechea intermedia Leggett ex Britt. var. intermedia (Northern Pinweed, Round-fruit Pinweed, Large-pod Pinweed)
  • Lechea maritima Leggett ex B.S.P. var. virginica Hogdon (Virginia Beach Pinweed)
  • Lechea minor L. (Thyme-leaf Pinweed)
  • Lechea mucronata Raf. (Hairy Pinweed)
  • Lechea pulchella Raf. (Leggett's Pinweed)
  • Lechea pulchella Raf. var. pulchella (Leggett's Pinweed)
  • Lechea pulchella Raf. var. ramosissima (Hodgdon) Sorrie & Weakley (Leggett's Pinweed)
  • Lechea racemulosa Michx. (Common Pinweed, Illinois Pinweed)
  • Lechea tenuifolia Michx. (Slender Pinweed, Narrow-leaf Pinweed)
  • Leersia hexandra Sw. (Southern Cutgrass, Clubhead Cutgrass)
  • Leersia lenticularis Michx. (Catchfly Cutgrass)
  • Leersia oryzoides (L.) Sw. (Rice Cutgrass)
  • Leersia virginica Willd. (White Grass, White Cutgrass, Virginia Cutgrass)
  • Lejeunea blomquistii R.M. Schuster (Blomquist's Leafy Liverwort)
  • Lejeunea cavifolia (Ehrh.) Lindb.
  • Lejeunea deplanata Nees
  • Lejeunea flava (Sw.) Nees ssp. flava
  • Lejeunea laetevirens Nees & Mont.
  • Lejeunea lamacerina (Steph.) Schiffn. ssp. gemminata R.M. Schust.
  • Lejeunea ruthii (A. Evans) R.M. Schust.
  • Lemna aequinoctialis Welw. (Lesser Duckweed)
  • Lemna minor L. (Common Duckweed)
  • Lemna minuta Kunth (Least Duckweed)
  • Lemna obscura (C.F. Austin) E.H. Daubs (Little Duckweed)
  • Lemna perpusilla Torr. (Minute Duckweed)
  • Lemna trisulca L. (Star Duckweed)
  • Lemna valdiviana Phil. (Pale Duckweed)
  • Leontodon autumnalis L. ssp. autumnalis (Fall Dandelion)
  • Leontodon saxatilis Lam. ssp. saxatilis (Little Hawkbit)
  • Leonurus cardiaca L. ssp. cardiaca (Motherwort, Lion's-tail)
  • Leonurus japonicus Houtt. (Honeyweed, Chinese Motherwort)
  • Lepidium campestre (Linnaeus) R. Brown (Field Pepperweed, Field Peppergrass, Cow Cress)
  • Lepidium densiflorum Schrad. (Common Pepperweed, Prairie Peppergrass, Green-flowered Peppergrass)
  • Lepidium didymum L. (Lesser Swinecress)
  • Lepidium draba L. (Hoary Cress)
  • Lepidium ruderale Linnaeus (Narrowleaf Pepperwort)
  • Lepidium sativum L. (Garden Cress)
  • Lepidium virginicum L. var. virginicum (Virginia Pepperweed, Virginia Peppergrass, Common Peppergrass, Poor Man's Pepper)
  • Lepidozia reptans (L.) Dumort.
  • Leptobryum pyriforme (Hedw.) Wilson
  • Leptodictyum riparium (Hedw.) Warnst. (Wet Thread Moss)
  • Leptodontium viticulosoides (P. Beauvois) Wijk & Margadant var. sulphureum (Mll. Hal.) R.H. Zander
  • Leptoloma cognatum (Schultes) Chase (Fall Witch Grass)
  • Leptoscyphus cuneifolius (Hook.) Mitt. ssp. cuneifolius
  • Leskea australis Sharp
  • Leskea gracilescens Hedwig
  • Leskea obscura Hedwig
  • Leskea polycarpa Hedw.
  • Leskeella nervosa (Brid.) Loeske
  • Lespedeza angustifolia (Pursh) Ell. (Narrow-leaf Lespedeza, Narrow-leaf Bush-clover)
  • Lespedeza bicolor Turcz. (Shrubby Bush-clover, Bicolor Lespedeza, Shrub Lespedeza, )
  • Lespedeza capitata Michx. (Round-headed Lespedeza, Round-headed Bush-clover)
  • Lespedeza cuneata (Dum.-Cours.) G. Don (Sericea Lespedeza, Chinese Lespedeza)
  • Lespedeza frutescens (L.) Ell. (Violet Lespedeza, Violet Bush-clover)
  • Lespedeza hirta (L.) Hornemann var. curtissii (Clewell) Isely (Curtiss' Lespedeza)
  • Lespedeza hirta (L.) Hornemann var. hirta (Hairy Lespedeza, Hairy Bush-clover)
  • Lespedeza procumbens Michx. (Trailing Lespedeza, Trailing Bush-clover)
  • Lespedeza repens (L.) W. Bart. (Creeping Lespedeza, Creeping Bush-clover)
  • Lespedeza stuevei Nutt. (Tall Lespedeza, Velvety Lespedeza, Tall Bush-clover)
  • Lespedeza violacea (L.) Pers. (Wand Lespedeza, Wand Bush-clover)
  • Lespedeza virginica (L.) Britt. (Slender Lespedeza, Slender Bush-clover)
  • Leucanthemum lacustre (Brot.) Samp. (Portugese Daisy)
  • Leucanthemum vulgare Lam. (Oxeye Daisy)
  • Leucobryum albidum (Brid. ex P. Beauv.) Lindb. (White Moss)
  • Leucobryum glaucum (Hedw.) ngstr (Cushion Moss)
  • Leucodon andrewsianus (H.A. Crum & L.E. Anderson) W.D. Reese & L.E. Anderson
  • Leucodon brachypus Bridel
  • Leucodon julaceus (Hedw.) Sull.
  • Leucojum aestivum L. (Summer Snowflake)
  • Leucospora multifida (Michx.) Nutt. (Narrow-leaf Paleseed)
  • Leucothoe axillaris (Lam.) D. Don (Coastal Dog-hobble)
  • Leucothoe fontanesiana (Steud.) Sleumer (Highland Dog-hobble, Mountain Dog-hobble, Drooping Leucothoe)
  • Liatris aspera Michx. (Tall Blazing Star, Rough Blazing Star)
  • Liatris helleri T.C. Porter (Heller's Blazing Star)
  • Liatris pilosa (Aiton) Willd. (Grass-leaf Blazing Star, Grass-leaf Gayfeather)
  • Liatris resinosa Nutt. (Dense Blazing Star)
  • Liatris scariosa (L.) Willd. (Large Blazing Star, Eastern Blazing Star)
  • Liatris spicata (L.) Willd. (Dense Blazing Star)
  • Liatris squarrosa (L.) Michx. var. squarrosa (Scaly Blazing Star)
  • Liatris squarrulosa Michx. (Appalachian Blazing Star, Appalachian Gayfeather)
  • Liatris virgata Nuttall (Wand Blazing Star)
  • Ligusticum canadense (L.) Britt. (American Lovage)
  • Ligustrum japonicum Thunb. (Japanese Privet)
  • Ligustrum lucidum W.T. Aiton (Glossy Privet, Broadleaf Privet)
  • Ligustrum obtusifolium Sieb. & Zucc. var. obtusifolium (Border Privet)
  • Ligustrum obtusifolium Sieb. & Zucc. var. suave (Kitag.) H. Hara (Amur Privet)
  • Ligustrum ovalifolium Hassk. (California Privet)
  • Ligustrum quihoui Carriere (Wax-leaf Privet)
  • Ligustrum sinense Louriere (Chinese Privet)
  • Ligustrum vulgare L. (European Privet, Common Privet)
  • Lilaeopsis carolinensis Coult. & Rose (Carolina Lilaeopsis)
  • Lilaeopsis chinensis (L.) Kuntze (Marsh Lilaeopsis, Eastern Grasswort)
  • Lilium canadense L. (Canada Lily)
  • Lilium catesbaei Walter (Pine Lily, Catesby's Lily, Southern Red Lily)
  • Lilium grayi S. Wats. (Gray's Lily)
  • Lilium lancifolium Thunb. (Tiger Lily)
  • Lilium michauxii Poir. (Carolina Lily)
  • Lilium philadelphicum L. (Wood Lily)
  • Lilium pyrophilum M.W. Skinner & Sorrie (Sandhills Bog Lily)
  • Lilium superbum L. (Turk's-cap Lily)
  • Limnobium spongia (Bosc) L.C.Rich. ex Steud. (American Frog's-bit)
  • Limonium carolinianum (Walter) Britton (Sea Lavender, Carolina Sea Lavender)
  • Limosella australis R. Br. (Mudwort, Awl-leaf)
  • Linaria canadensis (L.) Dumont (Blue Toadflax, Canada Toadflax)
  • Linaria maroccana Hook. f. (Moroccan Toadflax)
  • Linaria texana Scheele (Texas Toadflax)
  • Linaria vulgaris P. Mill. (Butter-and-eggs, Yellow Toadflax)
  • Lindbergia brachyptera (Mitt.) Kindb.
  • Lindera benzoin (L.) Blume (Spicebush)
  • Lindernia anagallidea (Michx.) Pennell (Long-stalked False Pimpernel)
  • Lindernia dubia (L.) Pennell var. dubia (False Pimpernel, Yellow-seed False Pimpernel)
  • Lindernia dubia (L.) Pennell var. inundata (Pennell) Pennell (Estuarine False Pimpernel)
  • Linum floridanum (Planch.) Trel. var. floridanum (Florida Yellow Flax)
  • Linum intercursum Bickn. (Sandplain Flax)
  • Linum medium (Planch.) Britton var. texanum (Planch.) Fern. (Stiff Yellow Flax, Common Yellow Flax)
  • Linum striatum Walt. (Ridged Yellow Flax)
  • Linum sulcatum Riddell var. sulcatum (Grooved Yellow Flax)
  • Linum usitatissimum L. (Common Flax)
  • Linum virginianum L. (Virginia Yellow Flax, Woodland Flax)
  • Liochlaena lanceolata Nees
  • Liparis liliifolia (L.) L.C. Rich. ex Ker-Gawl. (Lily-leaved Twayblade, Large Twayblade)
  • Liparis loeselii (L.) L.C. Rich. (Bog Twayblade, Fen Orchid)
  • Liquidambar styraciflua L. (Sweetgum)
  • Liriodendron tulipifera L. (Tulip-Poplar, Yellow Poplar, Tuliptree)
  • Liriope muscari (Dcne.) Bailey (Big Blue Lilyturf)
  • Liriope spicata Lour. (Creeping Lilyturf)
  • Lithospermum canescens (Michx.) Lehm. (Hoary Puccoon)
  • Lithospermum caroliniense (Walt. ex J.F.Gmel.) MacM. (Golden Puccoon)
  • Lithospermum latifolium Michx. (American Gromwell, American Stoneseed)
  • Lithospermum parviflorum Weakley, Witsell, & D. Estes (Shaggy False Gromwell, Eastern Prairie Marbleseed)
  • Lithospermum tuberosum Rugel ex DC. (Tuberous Gromwell, Tuberous Stoneseed)
  • Lithospermum virginianum L. (Virginia False Gromwell, Virginia Marbleseed)
  • Litsea aestivalis (L.) Fern. (Pondspice)
  • Lobelia cardinalis L. (Cardinal Flower)
  • Lobelia elongata Small (Long-leaf Lobelia, Elongated Lobelia)
  • Lobelia georgiana McVaugh (Southern Lobelia)
  • Lobelia inflata L. (Indian Tobacco)
  • Lobelia nuttallii J. A.Schultes (Nuttall's Lobelia)
  • Lobelia puberula Michaux (Downy Lobelia)
  • Lobelia siphilitica L. (Great Blue Lobelia)
  • Lobelia spicata Lam. (Pale-spike Lobelia)
  • Lobelia spicata Lam. var. scaposa McVaugh (Pale-spike Lobelia)
  • Lobelia spicata Lam. var. spicata (Pale-spike Lobelia)
  • Lobularia maritima (Linnaeus) Desvaux (Sweet Alyssum)
  • Loeskeobryum brevirostre (Brid.) M. Fleisch. ex Broth.
  • Lolium arundinaceum (Schreb.) Darbysh. (Tall Fescue, Alta Fescue)
  • Lolium perenne L. (Rye Grass)
  • Lolium perenne L. var. aristatum Willd. (Italian Rye Grass, Annual Rye Grass)
  • Lolium perenne L. var. perenne (English Rye Grass, Perennial Rye Grass)
  • Lolium pratense (Huds.) Darbysh. (Meadow Fescue)
  • Lolium temulentum L. (Darnel)
  • Lonicera canadensis Bartr. ex Marsh. (American Fly-honeysuckle)
  • Lonicera dioica L. (Limber Honeysuckle, Red Honeysuckle)
  • Lonicera fragrantissima Lindl. & Paxton (Winter Honeysuckle, Sweet Breath-of-spring)
  • Lonicera japonica Thunb. (Japanese Honeysuckle)
  • Lonicera maackii (Rupr.) Maximowicz var. maackii (Amur Honeysuckle)
  • Lonicera morrowii Gray (Morrow's Honeysuckle)
  • Lonicera sempervirens L. (Trumpet Honeysuckle, Coral Honeysuckle)
  • Lonicera standishii Jacq. (Standish's Honeysuckle)
  • Lonicera tatarica L. (Tartarian Honeysuckle)
  • Lonicera xylosteum L. (European Fly-honeysuckle)
  • Lonicera bella Zabel (Showy Honeysuckle)
  • Lophocolea appalachiana R. M. Schuster
  • Lophocolea bidentata (L.) Dumort.
  • Lophocolea coadunata (Sw.) Mont.
  • Lophocolea heterophylla (Schrad.) Dum.
  • Lophocolea minor Nees
  • Lorinseria areolata (L.) Presl (Netted Chain Fern)
  • Lotus corniculatus L. (Bird's-foot Trefoil)
  • Lotus tenuis Waldst. & Kit. ex Willd. (Slender Birdsfoot-trefoil)
  • Ludwigia alata Elliott (Winged Seedbox, Winged Primrose-willow)
  • Ludwigia alternifolia L. (Seedbox, Alternate-leaved Seedbox)
  • Ludwigia bonariensis (M. Micheli) Hara (Carolina Primrose-willow)
  • Ludwigia brevipes (B.H. Long ex Britt., A. Braun & Small) Eames (Long Beach Seedbox, Long Beach Primrose-willow)
  • Ludwigia decurrens Walter (Wing-leaved Primrose-willow, Winged Water-primrose)
  • Ludwigia glandulosa Walter (Cylindric-fruited Primrose-willow)
  • Ludwigia hexapetala (Hook. & Arn.) Zardini, Gu, & Raven (Large-flowered Primrose-willow, Common Water-primrose)
  • Ludwigia hirtella Raf. (Rafinesque's Seedbox, Spindleroot)
  • Ludwigia leptocarpa (Nuttall) Hara (Angle-stem Primrose-willow, Angle-stem Water-primrose)
  • Ludwigia linearis Walter (Narrow-leaved Seedbox)
  • Ludwigia palustris (L.) Elliott (Marsh Seedbox, Common Water-purslane)
  • Ludwigia peploides (H.B.K.) Raven var. glabrescens (Kuntze)Shinners (Floating Primrose-willow, Creeping Water-primrose)
  • Ludwigia pilosa Walter (Hairy Seedbox, Hairy Primrose-willow)
  • Ludwigia polycarpa Short & Peter (Many-fruited Primrose-willow)
  • Ludwigia ravenii Peng (Raven's Seedbox, Raven's Primrose-willow)
  • Ludwigia sphaerocarpa Elliott (Globe-fruited Seedbox, Globe-fruited Primrose-willow)
  • Ludwigia virgata Michx. (Savanna Seedbox, Savanna Primrose-willow)
  • Luffa acutangula (L.) Roxb. var. acutangula (Sponge Gourd)
  • Luffa aegyptiaca P. Mill. (Sponge Gourd, Vegetable Gourd)
  • Lunaria annua Linnaeus (Annual Honesty, Money Plant, Silver-dollar)
  • Lunularia cruciata (L.) Dumort. ex Lindb.
  • Lupinus perennis L. (Sundial Lupine)
  • Luzula acuminata Raf. (Hairy Woodrush)
  • Luzula acuminata Raf. var. acuminata (Northern Hairy Woodrush)
  • Luzula acuminata Raf. var. carolinae (S. Wats.) Fern. (Southern Hairy Woodrush)
  • Luzula bulbosa (Wood) Smyth & Smyth (Bulbous Woodrush)
  • Luzula echinata (Small) F.J. Hermann (Spreading Woodrush)
  • Luzula multiflora (Ehrhart) Lejeune var. multiflora (Common Woodrush)
  • Lycium barbarum L. (Common Matrimony-vine, Wolfberry, Goji Berry)
  • Lycium chinense P. Miller (Chinese Wolfberry)
  • Lycopodiella alopecuroides (L.) Cranfill (Foxtail Clubmoss)
  • Lycopodiella appressa (Chapman) Cranfill (Southern Bog Clubmoss)
  • Lycopodiella inundata (L.) Holub (Northern Bog Clubmoss)
  • Lycopodiella gilmanii A. Haines
  • Lycopodium clavatum L. (Staghorn Clubmoss, Running Clubmoss)
  • Lycopus americanus Muhl. ex W. Bart. (American Bugleweed)
  • Lycopus angustifolius Elliott (Narrow-leaf Bugleweed, Southern Bog Water Horehound)
  • Lycopus europaeus L. (European Bugleweed, Gypsywort)
  • Lycopus rubellus Moench (Taper-leaf Water Horehound, Stalked Water Horehound)
  • Lycopus uniflorus Michx. (Northern Bugleweed)
  • Lycopus virginicus L. (Virginia Bugleweed, Virginia Water Horehound)
  • Lygodium japonicum (Thunb.) Swartz (Japanese Climbing Fern)
  • Lygodium palmatum (Bernh.) Sw. (American Climbing Fern, Hartford Fern)
  • Lyonia ligustrina (L.) DC. var. foliosiflora (Michx.) Fern. (Southern Maleberry, He-Huckleberry)
  • Lyonia ligustrina (L.) DC. var. ligustrina (Maleberry, He-Huckleberry)
  • Lyonia lucida (Lam.) K. Koch (Shining Fetterbush)
  • Lyonia mariana (L.) D. Don (Staggerbush)
  • Lysimachia clethroides Duby (Gooseneck Loosestrife)
  • Lysimachia japonica Thunberg (Japanese Loosestrife)
  • Lysimachia nummularia L. (Moneywort, Creeping Jenny)
  • Lysimachia quadrifolia L. (Whorled Loosestrife)
  • Lysimachia terrestris (L.) B.S.P. (Swamp Loosestrife, Bog Loosestrife, Swamp Candles)
  • Lysimachia vulgaris L (Garden Loosestrife, Yellow Loosestrife)
  • Lythrum alatum Pursh (Northern Winged Loosestrife)
  • Lythrum lanceolatum Elliott (Southern Winged Loosestrife)
  • Lythrum lineare L. (Narrow-leaf Loosestrife, Wand Loosestrife, Salt Marsh Loosestrife)
  • Lythrum salicaria L. (Purple Loosestrife)
  • Macleaya cordata (Willd.) R. Brown (Plume-poppy, Tree-celandine)
  • Maclura pomifera (Raf.) Schneid. (Osage Orange, Hedge Apple, Bois-d'arc)
  • Macrothelypteris torresiana (Gaud.) Ching (Swordfern)
  • Madia sativa Molina (Chilean Tarweed)
  • Magnolia acuminata (L.) L. (Cucumber Magnolia, Cucumber-tree)
  • Magnolia fraseri Walt. (Fraser Magnolia, Earleaf Umbrella- tree)
  • Magnolia grandiflora L. (Southern Magnolia, Bull-bay)
  • Magnolia macrophylla Michx. (Bigleaf Magnolia)
  • Magnolia tripetala (L.) L. (Umbrella Magnolia)
  • Magnolia virginiana L. (Sweetbay, Sweetbay Magnolia, Swamp Magnolia)
  • Mahonia bealei (Fortune) Carr. (Leatherleaf Mahonia, Chinese Mahonia, Holly-grape)
  • Maianthemum canadense Desf. (Canada Mayflower, False Lily-of-the-valley)
  • Maianthemum racemosum (L.) Link (Eastern Solomon's-plume, False Solomon's-seal)
  • Maianthemum stellatum (L.) Link (Starry Solomon's-plume, Starry False Solomon's-seal)
  • Malaxis bayardii Fern. (Appalachian Adder's-mouth)
  • Malaxis spicata Swartz (Florida Adder's-mouth)
  • Malaxis unifolia Michaux (Green Adder's-mouth)
  • Malus angustifolia (Aiton) Michx. (Southern Crabapple)
  • Malus baccata (L.) Borkh. (Siberian Crabapple)
  • Malus coronaria (L.) P. Mill. (Sweet Crabapple)
  • Malus domestica (Suckow) Borkh. (Common Apple)
  • Malus floribunda Sieb. ex Van Houtte (Japanese Flowering Crabapple)
  • Malus prunifolia (Willd.) Borkh. (Plumleaf Crabapple)
  • Malus toringo (Sieb.) Sieb. (Toringo Crabapple)
  • Malva moschata L. (Musk Mallow)
  • Malva neglecta Wallroth (Common Mallow, Cheeses)
  • Malva sylvestris L. (High Mallow)
  • Malvastrum hispidum (Pursh) Hochr. (Hispid False Mallow, Yellow False Mallow)
  • Manfreda virginica (L.) Salisbury ex Rose (Rattlesnake-master, Eastern False-aloe)
  • Mannia fragrans (Balb.) Frye & Clarke ssp. fragrans
  • Marchantia polymorpha L.
  • Marchantia quadrata Scop.
  • Marrubium vulgare L. (Common Horehound, White Horehound)
  • Marshallia legrandii Weakley (Tall Barbara's-buttons)
  • Marshallia obovata (Walt.) Beadle & F.E. Boynt. var. obovata (Piedmont Barbara's-buttons, Spoon-leaved Barbara's-buttons)
  • Marsilea mutica Mettenius (Australian Water-clover)
  • Marsupella emarginata (Ehrh.) Dumort.
  • Marsupella paroica R.M. Schuster
  • Marsupella sphacelata (Giesecke ex Lindenb.) Dumort.
  • Matelea carolinensis (Jacq.) Woods. (Carolina Milkvine)
  • Matelea decipiens (Alexander) Woods. (Old-field Milkvine)
  • Matelea obliqua (Jacq.) Woods. (Climbing Milkvine)
  • Matricaria chamomilla L. (German Chamomile)
  • Matricaria discoidea DC. (Pineapple Weed, Rayless Chamomile)
  • Matteuccia struthiopteris (L.) Todaro var. pensylvanica (Willd.) C.V. Morton (Ostrich Fern)
  • Mazus miquelii Makino (Creeping Mazus, Miquel's Mazus)
  • Mazus pumilus (Burm. f.) Steenis (White-flowered Mazus, Japanese Mazus)
  • Mecardonia acuminata (Walter) Small var. acuminata (Mecardonia, Axil-flower)
  • Medeola virginiana L. (Indian Cucumber-root)
  • Medicago arabica (L.) Huds. (Spotted Medick, Spotted Bur-clover)
  • Medicago falcata L. (Yellow Alfalfa, Sickle Medick)
  • Medicago lupulina L. (Black Medick)
  • Medicago minima (L.) L. (Small Medick, Bur Medick, Little Bur-clover)
  • Medicago sativa L. (Alfalfa, Lucerne)
  • Meehania cordata (Nutt.) Britt. (Meehan's Mint, Creeping Mint)
  • Melampyrum lineare Desr. (Cow-wheat)
  • Melanthium hybridum Walter (Crisped Bunchflower, Broadleaf Bunchflower)
  • Melanthium parviflorum (Michaux) S. Watson (Mountain Bunchflower, Small-flowered False-hellebore)
  • Melanthium virginicum L. (Bog Bunchflower, Virginia Bunchflower)
  • Melia azedarach L. (Chinaberry)
  • Melica mutica Walt. (Two-flower Melic)
  • Melica nitens (Scribn.) Nutt. ex Piper (Three-flower Melic)
  • Melilotus albus Medikus (White Sweet-clover)
  • Melilotus indicus (L.) All. (Small Melilot, Sourclover)
  • Melilotus officinalis (L.) Lam. (Yellow Sweet-clover)
  • Melissa officinalis L. (Lemon Balm, Common Balm)
  • Melochia corchorifolia L (Chocolate-weed)
  • Melothria pendula L. (Melonette, Creeping Cucumber, Guadeloupe Cucumber)
  • Menispermum canadense L. (Canada Moonseed, Common Moonseed, Yellow Parilla)
  • Mentha aquatica L. (Water Mint, Lemon Mint, Orange Mint)
  • Mentha canadensis L. (Canada Mint, Wild Mint)
  • Mentha longifolia (L.) L. (Long-leaved mint)
  • Mentha spicata L. (Spearmint)
  • Mentha suaveolens Ehrh. (Pineapple Mint, Round-leaved Mint)
  • Mentha gracilis Sole (Ginger Mint, Creeping Whorled Mint)
  • Mentha piperita L. (Peppermint)
  • Mentha rotundifolia (L.) Huds. (Apple Mint)
  • Menyanthes trifoliata L. (Buckbean, Bogbean)
  • Mertensia virginica (L.) Pers. ex Link (Virginia Bluebells, Virginia Cowslip)
  • Metzgeria conjugata Lindberg
  • Metzgeria consanguinea Schiffn.
  • Metzgeria crassipilis (Lindb.) A. Evans
  • Metzgeria furcata (L.) Corda
  • Metzgeria leptoneura Spruce
  • Metzgeria myriopoda Lindberg
  • Micranthemum micranthemoides (Nutt.) Wettst. (Nuttall's Micranthemum)
  • Micranthemum umbrosum (J.F. Gmel.) Blake (Shade Mudflower)
  • Micranthes careyana (Gray) Small (Carey's Saxifrage)
  • Micranthes caroliniana (Gray) Small (Carolina Saxifrage)
  • Micranthes micranthidifolia (Haw.) Small (Lettuce Saxifrage, Lettuce-leaved Saxifrage, Brook Lettuce)
  • Micranthes pensylvanica (L.) Haw. (Swamp Saxifrage)
  • Micranthes petiolaris (Raf.) Bush var. petiolaris (Michaux's Saxifrage, Cliff Saxifrage)
  • Micranthes virginiensis (Michaux) Small (Early Saxifrage)
  • Microlejeunea bullata (Taylor) Steph.
  • Microlejeunea ulicina (Taylor) Steph.
  • Micromitrium synoicum (James) Aust.
  • Micromitrium tenerum (Bruch & Schimp.) Crosby
  • Microstegium vimineum (Trin.) A. Camus (Japanese Stiltgrass, Nepalese Brown-top, Japanese Grass)
  • Mikania scandens (L.) Willd. (Climbing Hempweed)
  • Milium effusum L. var. cisatlanticum Fern. (Tall Millet Grass, American Millet Grass, American Wood Millet)
  • Mimosa microphylla Dryander (Little-leaf Sensitive-brier)
  • Mimulus alatus Aiton (Winged Monkeyflower)
  • Mimulus ringens L. var. ringens (Square-stemmed Monkeyflower, Allegheny Monkeyflower)
  • Mirabilis jalapa L. (Common Four-o'clock, Marvel-of-Peru)
  • Mirabilis nyctaginea (Michx.) MacM. (Heart-leaved Umbrella-wort, Wild Four-o'clock)
  • Miscanthus sinensis Anderss. (Chinese Silvergrass, Eulalia, Maiden Grass)
  • Misopates orontium (L.) Raf. (Lesser Snapdragon, Weasel's-snout)
  • Mitchella repens L. (Partridge-berry)
  • Mitella diphylla L. (Two-leaved Miterwort, Bishop's Cap)
  • Mitreola petiolata (J.F.Gmelin) Torrey and Gray (Lax Hornpod)
  • Mitreola sessilifolia (J.F.Gmelin) G.Don (Swamp Hornpod, Sessile-leaved Hornpod)
  • Mnesithea rugosa (Nutt.) de Koning & Sosef (Wrinkled Jointgrass)
  • Mnium hornum Hedwig
  • Mnium lycopodioides Schwgr.
  • Mnium marginatum (Dicks. ex With.) P. Beauv.
  • Mnium stellare Hedwig
  • Mnium thomsonii Schimp.
  • Modiola caroliniana (L.) G. Don (Carolina Bristle Mallow)
  • Moehringia lateriflora (L.) Fenzl (Grove Sandwort, Blunt-leaf Sandwort)
  • Moeroris tenella (Roxburgh) R.W. Bouman (Mascarene Island Leaf-flower)
  • Mollugo verticillata L. (Carpetweed, Green Carpetweed, Indian Chickweed)
  • Monarda brevis (Fosberg & Artz) Floden (Smoke Hole Bergamot)
  • Monarda clinopodia L. (White Bergamot, Basil Beebalm)
  • Monarda didyma L. (Scarlet Beebalm, Oswego Tea)
  • Monarda fistulosa L. (Wild Bergamot)
  • Monarda fistulosa L. var. fistulosa (Appalachian Bergamot)
  • Monarda fistulosa L. var. mollis (L.) Benth. (Eastern Bergamot)
  • Monarda fistulosa L. var. rubra A. Gray (Red Bergamot)
  • Monarda media Willd. complex (Purple Bergamot)
  • Monarda punctata L. var. punctata (Horsemint, Spotted Beebalm)
  • Monotropa uniflora L. (Indian Pipe)
  • Monotropsis odorata Schwein. ex Ell. (Sweet Pinesap)
  • Montia fontana L. (Water Blinks)
  • Montia linearis (Dougl. ex Hook.) Greene (Narrow-leaved Montia)
  • Morella caroliniensis (P. Miller) Small (Evergreen Bayberry, Pocosin Bayberry)
  • Morella cerifera (L.) Small (Southern Bayberry, Wax-Myrtle)
  • Morella pensylvanica (Mirbel) Kartesz (Northern Bayberry)
  • Morella pusilla (Raf.) Weakley & D.B.Poind. (Dwarf Bayberry, Dwarf Wax Myrtle)
  • Morus alba L. (White Mulberry)
  • Morus rubra L. (Red Mulberry)
  • Mosla scabra (Thunb.) C.Y. Wu & H.W. Li (Mosla, Miniature Beefsteak Plant)
  • Muhlenbergia bushii Pohl (Bush's Muhly)
  • Muhlenbergia capillaris (Lam.) Trin. (Hair-awn Muhly, Long-awn Hairgrass)
  • Muhlenbergia cuspidata (Torr. ex Hook.) Rydb. (Plains Muhly)
  • Muhlenbergia expansa (Poir.) Trin. (Cut-over Muhly, Savanna Hairgrass)
  • Muhlenbergia frondosa (Poir.) Fern. (Smooth Wirestem Muhly)
  • Muhlenbergia glabrifloris Scribn. (Inland Muhly, Smooth Muhly)
  • Muhlenbergia glomerata (Willd.) Trin. (Marsh Muhly, Spiked Muhly)
  • Muhlenbergia mexicana (L.) Trin. (Hairy Wirestem Muhly)
  • Muhlenbergia schreberi J.F. Gmel. (Nimblewill)
  • Muhlenbergia sobolifera (Muhl. ex Willd.) Trin. (Rock Muhly, Cliff Muhly)
  • Muhlenbergia sylvatica (Torr.) Torr. ex Gray (Woodland Muhly)
  • Muhlenbergia tenuiflora (Willd.) B.S.P. (Slender Muhly)
  • Mummenhoffia alliacea (L.) Esmailbegi & Al-Shehbaz (Roadside Pennycress, Garlic Pennycress)
  • Murdannia keisak (Hasskarl) Handel-Mazzetti (Marsh Dewflower)
  • Muscadinia rotundifolia (Michx.) Small var. rotundifolia (Muscadine Grape, Scuppernong)
  • Muscari botryoides (L.) P. Mill. (Common Grape-hyacinth)
  • Muscari comosum (L.) P. Mill. (Tassel Grape-hyacinth)
  • Muscari neglectum Guss. ex Ten. (Grape-hyacinth)
  • Myosotis arvensis (L.) Hill (Field Forget-me-not, Rough Forget-me-not)
  • Myosotis discolor Pers. (Yellow-and-blue Forget-me-not)
  • Myosotis laxa Lehm. ssp. laxa (Smaller Forget-me-not, Tufted Forget-me-not)
  • Myosotis macrosperma Englem. (Large-seed Forget-me-not)
  • Myosotis scorpioides L. (True Forget-me-not, Water Forget-me-not)
  • Myosotis stricta Link ex Roemer & J.A.Schultes (Small-flowered Forget-me-not, Blue Scorpion-grass)
  • Myosotis verna Nutt. (Early Forget-me-not, Spring Forget-me-not)
  • Myosurus minimus L. (Tiny Mousetail)
  • Myrica gale L. (Sweet Gale, Bog-Myrtle)
  • Myriocoleopsis minutissima (Sm.) R.L. Zhu, Y. Yu & Pocs ssp. minutissima
  • Myriophyllum aquaticum (Vell.) Verdc. (Parrot Feather, Brazilian Water-milfoil)
  • Myriophyllum heterophyllum Michx. (Variable Water-milfoil, Two-leaf Water-milfoil)
  • Myriophyllum humile (Raf.) Morong (Low Water-milfoil)
  • Myriophyllum laxum Shuttlew. ex Chapm. (Loose Water-milfoil)
  • Myriophyllum pinnatum (Walt.) BSP (Cut-leaf Water-milfoil)
  • Myriophyllum spicatum L. (Eurasian Water-milfoil)
  • Myriopteris alabamensis (Buckley) Grusz & Windham (Alabama Lip Fern)
  • Myriopteris gracilis Fe (Slender Lip Fern)
  • Myriopteris lanosa (Michaux) Grusz & Windham (Hairy Lip Fern)
  • Myriopteris rufa Fe (Chestnut Lip Fern)
  • Myriopteris tomentosa (Link) Fe (Woolly Lip Fern)
  • Myurella sibirica (Mll. Hal.) Reimers
  • Myzorrhiza riparia (L.T. Collins) Weakley (River Broomrape)
  • Nabalus albus (L.) Hooker (White Rattlesnake-root)
  • Nabalus altissimus (L.) Hooker (Tall Rattlesnake-root)
  • Nabalus autumnalis (Walter) Weakley (Slender Rattlesnake-root)
  • Nabalus crepidineus (Michaux) A.P. DeCandolle (Midwestern Rattlesnake-Root)
  • Nabalus roanensis Chickering (Roan Mountain Rattlesnake-root)
  • Nabalus serpentarius (Pursh) Hooker (Lion's foot, Cankerweed)
  • Nabalus trifoliolatus Cassini (Gall-of-the-earth)
  • Najas canadensis Michx. (Canada Naiad, Northern Naiad)
  • Najas gracillima (A. Braun ex Engelm.) Magnus (Slender Naiad, Bushy Naiad)
  • Najas guadalupensis (Spreng.) Magnus var. guadalupensis (Southern Naiad, Common Naiad)
  • Najas minor All. (Brittle Naiad, Spinyleaf Naiad)
  • Nandina domestica Thunberg (Nandina, Heavenly Bamboo, Sacred-bamboo)
  • Nanopanax trifolius (L.) A. Haines (Dwarf Ginseng)
  • Napaea dioica L. (Glade Mallow)
  • Narcissus poeticus L. (Poet's Narcissus, Pheasant's-eye Daffodil)
  • Narcissus pseudonarcissus L. (Common Daffodil)
  • Narcissus tazetta L. (Bunch-flowered Daffodil)
  • Narcissus incomparabilis P. Mill. (pro sp.) (Nonesuch Daffodil)
  • Narcissus medioluteus P. Mill. (Two-flower Narcissus)
  • Nardia lescurii (Austin) Underw.
  • Nasturtium officinale R. Brown (Watercress)
  • Neckera besseri (Lobarzewski) Juratzka
  • Neckera complanata (Hedw.) Huebener
  • Neckera pennata Hedwig (Shingle Moss)
  • Neillia incisa (Thunberg) S.H. Oh (Lace Shrub)
  • Nekemias arborea (L.) J. Wen & Boggan (Peppervine)
  • Nelumbo lutea Willd. (American Lotus, American Lotus-lily, Yellow Lotus)
  • Nelumbo nucifera Gaertner (Sacred Lotus, Oriental Lotus-Lily, Pink Lotus)
  • Nemophila aphylla (L.) Brummitt (Small-flower Baby-blue-eyes)
  • Neobeckia aquatica (Eaton) Greene (Lake Cress)
  • Neoorthocaulis attenuatus (Mart.) L. Sderstr., DeRoo & Hedd.
  • Neottia bifolia (Raf.) Bombach (Southern Twayblade)
  • Neottia smallii (Wieg.) Szlachetko (Appalachian Twayblade, Small's Twayblade, Kidneyleaf Twayblade)
  • Nepeta cataria L. (Catnip, Catmint)
  • Nephroia carolina (L.) Lian Lian & Wei Wang (Carolina Coralbead, Carolina Snailseed, Red-berried Moonseed)
  • Nestronia umbellula Raf. (Nestronia, Leechbrush)
  • Nicandra physalodes (L.) Gaertner (Apple-of-Peru)
  • Nigella damascena L. (Love-in-a-mist, Fennel-flower)
  • Noccaea perfoliata (Linnaeus) Al-Shehbaz (Perfoliate Pennycress, Thoroughwort Pennycress)
  • Nothoscordum bivalve (L.) Britt. (Crow-poison, False Garlic)
  • Nothoscordum gracile (Dryander) Stearn (Fragrant False Garlic)
  • Notothylas orbicularis (Schwein.) Sull.
  • Nowellia curvifolia (Dicks.) Mitt.
  • Nuphar advena (Ait.) Ait.f. (Yellow Pond-lily, Common Spatterdock)
  • Nuphar sagittifolia (Walter) Pursh (Narrow-leaved Spatterdock)
  • Nymphaea odorata Aiton ssp. odorata (White Water-lily, Fragrant Water-lily)
  • Nymphoides aquatica (J.F. Gmel.) Kuntze (Big Floating Heart, Banana Floating Heart)
  • Nymphoides peltata (Gmelin) Kuntze (Yellow Floating Heart)
  • Nyssa aquatica L. (Water Tupelo)
  • Nyssa biflora Walt. (Swamp Tupelo, Swamp Black Gum)
  • Nyssa sylvatica Marshall (Black Gum, Sour Gum)
  • Obolaria virginica L. (Pennywort)
  • Oclemena acuminata (Michx.) Greene (Whorled Wood Aster)
  • Odontoschisma denudatum (Nees) Dumort.
  • Odontoschisma sphagni (Dicks.) Dumort.
  • Oenanthe javanica (Blume) DC (Water Celery, Java Water Dropwort)
  • Oenothera argillicola Mackenzie (Shale Barren Evening-primrose)
  • Oenothera biennis L. (Common Evening-primrose)
  • Oenothera curtiflora W.L. Wagner & Hoch (Small-flowered Gaura)
  • Oenothera fruticosa L. (Narrow-leaf Sundrops, Southern Sundrops)
  • Oenothera gaura W.L. Wagner & Hoch (Biennial Gaura, Northeastern Gaura)
  • Oenothera humifusa Nuttall (Sea-beach Evening-primrose)
  • Oenothera laciniata Hill (Cutleaf Evening-primrose)
  • Oenothera linifolia Nuttall (Threadleaf Sundrops, Flaxleaf Sundrops)
  • Oenothera parviflora L. (Small-flowered Evening-primrose)
  • Oenothera perennis L. (Small Sundrops, Little Sundrops)
  • Oenothera pilosella Raf. ssp. pilosella (Meadow Evening-primrose, Prairie Sundrops)
  • Oenothera riparia Nuttall (Riverbank Evening Primrose)
  • Oenothera speciosa Nuttall (Pink Evening-primrose, Showy Evening-primrose, Pink-ladies)
  • Oenothera tetragona Roth (Sundrops)
  • Oenothera triloba Nuttall (Stemless Evening Primrose)
  • Oldenlandia boscii (DC) Chapman (Bosc's Bluets)
  • Oldenlandia corymbosa L. (Diamond-flower)
  • Oncophorus rauei (Austin) Grout
  • Oncophorus virens (Hedw.) Brid.
  • Oncophorus wahlenbergii Brid.
  • Onoclea sensibilis L. (Sensitive Fern, Bead Fern)
  • Onopordum acanthium L. ssp. acanthium (Scotch Thistle, Cotton Thistle)
  • Ophioglossum engelmannii Prantl (Limestone Adder's-tongue, Engelmann's Adder's-tongue)
  • Ophioglossum petiolatum Hook. (Long-stem Adder's-tongue)
  • Ophioglossum pusillum Raf. (Northern Adder's-tongue)
  • Ophioglossum pycnostichum (Fernald) A. & D. Love (Southern Adder's-tongue)
  • Oplismenus undulatifolius (Ard.) P. Beauv. (Wavyleaf Basketgrass, Wavyleaf Grass)
  • Opuntia cespitosa Raf.
  • Opuntia humifusa (Raf.) Raf. (Eastern Prickly-pear)
  • Opuntia humifusa complex (Eastern Prickly-pear)
  • Opuntia mesacantha Raf. ssp. mesacantha (Southeastern Prickly-pear)
  • Orbexilum onobrychis (Nutt.) Rydb. (Lance-leaf Scurfpea, French-grass)
  • Orbexilum psoralioides (Walter) Vincent (Sampson's Snakeroot)
  • Oreojuncus trifidus (L.) Zvesk Drbkov & Kirschner (Highland Rush)
  • Origanum vulgare L. (Wild Marjoram)
  • Ornithogalum nutans L. (Drooping Star-of-Bethlehem)
  • Ornithogalum umbellatum L. (Common Star-of-Bethlehem)
  • Orobanche minor J.E. Smith (Common Broomrape, Lesser Broomrape, Small Broomrape)
  • Orontium aquaticum L. (Golden Club)
  • Orthilia secunda (L.) House (One-sided Shinleaf, One-sided Pyrola)
  • Orthotrichum anomalum Hedw.
  • Orthotrichum elegans Schwgr. ex Hook. & Grev.
  • Orthotrichum exiguum Sullivant
  • Orthotrichum keeverae H.A. Crum & L.E. Anderson (Keever's Bristle Moss)
  • Orthotrichum lescurii Austin
  • Orthotrichum ohioense Sullivant & Lesquereux
  • Orthotrichum pumilum Swartz
  • Orthotrichum pusillum Mitten
  • Orthotrichum stellatum Bridel
  • Orthotrichum strangulatum P. Beauv.
  • Orychophragmus violaceus (L.) O.E. Schulz (Chinese Violet Cress)
  • Oryzopsis asperifolia Michx. (Rough-leaved Ricegrass, White-grained Mountain Ricegrass)
  • Oshuna crassipes (Martius) A. Haines (Water Hyacinth)
  • Osmanthus heterophyllus D. Don (Holly Osmanthus)
  • Osmorhiza claytonii (Michx.) C.B. Clarke (Sweet Cicely)
  • Osmorhiza longistylis (Torr.) DC. (Aniseroot)
  • Osmunda spectabilis Willd. (Royal Fern)
  • Osmunda ruggii R. Tryon
  • Osmundastrum cinnamomeum (L.) C. Presl var. cinnamomeum (Cinnamon Fern)
  • Osmundastrum cinnamomeum (L.) C. Presl var. glandulosum (Waters) McAvoy (Glandular Cinnamon Fern)
  • Ostrya virginiana (P.Mill.) K.Koch (Hop-hornbeam, Eastern Hop-hornbeam, Ironwood)
  • Oxalis articulata Savigny (Red Wood-sorrel)
  • Oxalis colorea (Small) Fedde (Small's Wood-sorrel)
  • Oxalis corniculata L. (Creeping Wood-sorrel)
  • Oxalis dillenii Jacquin (Southern Yellow Wood-sorrel)
  • Oxalis florida Salisbury (Slender Yellow Wood-sorrel)
  • Oxalis grandis Small (Great Yellow Wood-sorrel)
  • Oxalis montana Raf. (Mountain Wood-sorrel, White Wood-sorrel)
  • Oxalis stricta L. (Common Yellow Wood-sorrel)
  • Oxalis violacea L. (Violet Wood-sorrel)
  • Oxybasis glauca (L.) Fuentes (Oakleaf Goosefoot)
  • Oxydendrum arboreum (L.) DC. (Sourwood, Sorrel Tree)
  • Oxypolis rigidior (L.) Raf. (Cowbane, Stiff Cowbane)
  • Oxypolis ternata (Nutt.) Heller (Savanna Cowbane)
  • Oxyrrhynchium hians (Hedw.) Loeske
  • Pachysandra terminalis Sieb. & Zucc. (Pachysandra, Japanese-spurge)
  • Packera anonyma (Wood) W.A. Weber & A. Love (Small's Ragwort)
  • Packera antennariifolia (Britton) W.A. Weber & A. Love (Shale-barren Ragwort)
  • Packera aurea (L.) A. & D. Love (Golden Ragwort, Heartleaf Ragwort)
  • Packera crawfordii (Britton) A.M. Mahoney & R.R. Kowal (Crawford's Ragwort)
  • Packera millefolium (T. & G.) W.A. Weber & A. Love (Yarrow-leaved Ragwort)
  • Packera obovata (Muhl. ex Willd.) W.A. Weber & A. Love (Round-leaved Ragwort, Running Ragwort)
  • Packera paupercula (Michaux) . & D. Lve var. appalachiana A.M. Mahoney; (Appalachian Ragwort)
  • Packera paupercula (Michx.) A. & D. Love var. paupercula (Balsam Ragwort)
  • Packera tomentosa (Michx.) C. Jeffrey (Woolly Ragwort)
  • Pallavicinia lyellii (Hook.) Carruth.
  • Palustricodon aparinoides (Pursh) Morin var. aparinoides (Marsh Bellflower)
  • Panax quinquefolius L. (Ginseng, American Ginseng, Sang)
  • Panicum amarulum Hitchc. & Chase (Beach Panic Grass, Southern Seabeach Grass)
  • Panicum amarum complex (Sea-beach Grass, Beach Panic Grass)
  • Panicum amarum Ell. (Bitter Seabeach Grass)
  • Panicum capillare L. ssp. capillare (Witch Panic Grass)
  • Panicum dichotomiflorum Michx. var. dichotomiflorum (Spreading Panic Grass, Fall Panic Grass)
  • Panicum flexile (Gattinger) Scribn. (Wiry Panic Grass)
  • Panicum hemitomon J.A. Schultes (Maidencane)
  • Panicum miliaceum L. (Broomcorn Millet, Hog Millet)
  • Panicum philadelphicum Bernh. ex Trin. ssp. gattingeri (Nash) Freckm. & Lelong (Gattinger's Panic Grass)
  • Panicum philadelphicum Bernh. ex Trin. ssp. philadelphicum (Philadelphia Panic Grass)
  • Panicum virgatum L. (Switchgrass)
  • Panicum virgatum L. var. cubense Griseb. (Blunt Switchgrass)
  • Panicum virgatum L. var. spissum Linder (Tufted Switchgrass)
  • Panicum virgatum L. var. virgatum (Switchgrass)
  • Papaver dubium L. (Field Poppy, Long-headed Poppy)
  • Papaver orientale L. (Oriental Poppy)
  • Papaver rhoeas L. (Corn Poppy)
  • Papaver somniferum L. (Opium Poppy, Common Poppy)
  • Paraleucobryum longifolium (Ehrh. ex Hedw.) Loeske (Silver Broom Moss)
  • Parapholis incurva (L.) C.E. Hubbard (Sickle Grass)
  • Parietaria judaica L. (Spreading Pellitory, Pellitory-of-the-wall)
  • Parietaria pensylvanica Muhl. ex Willd. (Pennsylvania Pellitory, Rock Pellitory)
  • Parnassia asarifolia Vent. (Kidney-leaved Grass-of-Parnassus, Appalachian Grass-of-Parnassus, Brook Parnassia)
  • Parnassia grandifolia DC. (Large-leaved Grass-of-Parnassus, Bigleaf Grass-of-Parnassus)
  • Parogonum ciliinode (Michaux) Desjardins & J.P. Bailey (Fringed Bindweed, Fringed Black Bindweed)
  • Paronychia argyrocoma (Michx.) Nutt. (Silverling, Silver Whitlow-wort)
  • Paronychia baldwinii (Torr. & Gray) Fenzl ex Walp. ssp riparia (Chapman) Chaudhri (Baldwin's Nailwort)
  • Paronychia canadensis (L.) Wood (Smooth Forked Nailwort)
  • Paronychia fastigiata (Raf.) Fern. (Hairy Forked Nailwort)
  • Paronychia montana (Small) Pax & K. Hoffmann (Mountain Nailwort)
  • Paronychia virginica Spreng. var. virginica (Yellow Nailwort)
  • Parthenium auriculatum Britt. (Glade Wild Quinine)
  • Parthenium integrifolium L. var. integrifolium (Common Wild Quinine)
  • Parthenium integrifolium L. var. mabryanum Mears (Mabry's Wild Quinine)
  • Parthenocissus inserta (Kern.) Fritsch (Thicket Creeper, Woodbine)
  • Parthenocissus quinquefolia (L.) Planch. (Virginia-creeper)
  • Parthenocissus tricuspidata (Sieb. & Zucc.) Planch. (Boston-ivy)
  • Paspalum bifidum (Bertol.) Nash (Pitchfork Paspalum, Pitchfork Crowngrass)
  • Paspalum boscianum Fluegge (Bull Paspalum)
  • Paspalum dilatatum Poir. (Dallis Grass)
  • Paspalum dissectum (L.) L. (Walter's Paspalum, Mudbank Crowngrass)
  • Paspalum distichum L. (Joint Paspalum, Knotgrass)
  • Paspalum floridanum Michx. (Florida Paspalum)
  • Paspalum laeve Michx. (Field Paspalum)
  • Paspalum notatum Fluegge (Bahia Grass)
  • Paspalum praecox Walter var. curtisianum (Steud.) Vasey (Early Paspalum)
  • Paspalum pubiflorum Rupr. ex Fourn. var. glabrum Vasey (Hairy-seed Paspalum, Hairy-seed Crown-grass)
  • Paspalum repens P.J. Bergius (Water Paspalum, Horsetail Paspalum)
  • Paspalum setaceum Michx. (Thin Paspalum, Slender Paspalum)
  • Paspalum setaceum Michx. var. ciliatifolium (Michx.) Vasey (Hairy Slender Paspalum)
  • Paspalum setaceum Michx. var. mhlenbergii (Nash) Fern. (Muhlenberg's Slender Paspalum)
  • Paspalum setaceum Michx. var. setaceum (Thin Paspalum, Slender Paspalum)
  • Paspalum urvillei Steud. (Vasey's Grass)
  • Passiflora incarnata L. (Purple Passionflower, Maypop)
  • Passiflora lutea L. (Yellow Passionflower)
  • Pastinaca sativa L. (Wild Parsnip)
  • Patis racemosa (Sm.) Romasch., P.M. Peterson, & Soreng (Black-seed Ricegrass)
  • Paulownia tomentosa (Thunb.) Steud. (Royal Paulownia, Princess Tree, Empress Tree)
  • Paxistima canbyi A. Gray (Canby's Mountain-lover, Cliff-green, Rat-stripper)
  • Pedicularis canadensis L. (Lousewort, Wood-betony)
  • Pedicularis lanceolata Michx. (Swamp Lousewort)
  • Pediomelum canescens (Michx.) Rydb. (Buckroot, Hoary Scurfpea)
  • Pellaea atropurpurea (L.) Link (Purple Cliff-brake)
  • Pellaea glabella Mett. ex Kuhn ssp. glabella (Smooth Cliff-brake)
  • Pellia endiviifolia (Dicks.) Dumort.
  • Pellia epiphylla (L.) Corda
  • Pellia neesiana (Gottsche) Limpr.
  • Peltandra virginica (L.) Schott (Arrow-arum, Tuckahoe)
  • Penstemon australis Small (Southern Beard-tongue, Sandhill Beard-tongue)
  • Penstemon brevisepalus Pennell (Short-sepaled Beard-tongue)
  • Penstemon calycosus Small (Calico Beard-tongue, Long-sepal Beard-tongue)
  • Penstemon canescens (Britt.) Britt. (Gray Beard-tongue, Eastern Gray Beard-tongue)
  • Penstemon digitalis Nutt. ex Sims (Foxglove Beard-tongue, Tall White Beard-tongue)
  • Penstemon hirsutus (L.) Willd. (Hairy Beard-tongue)
  • Penstemon laevigatus Aiton (Smooth Beard-tongue, Eastern Smooth Beard-tongue)
  • Penstemon pallidus Small (Eastern Pale Beard-tongue)
  • Penthorum sedoides L. (Ditch Stonecrop)
  • Perilla frutescens (L.) Britt. (Perilla, Beefsteak Plant)
  • Persicaria amphibia (L.) Gray (Water Smartweed)
  • Persicaria arifolia (L.) Haraldson (Halberd-leaf Tearthumb)
  • Persicaria densiflora (Meisner) Moldenke (Dense-flowered Smartweed)
  • Persicaria extremiorientalis (Vorosch.) Tzvelev. (East Asian Smartweed)
  • Persicaria filiformis (Thunb.) Nakai (Japanese Jumpseed)
  • Persicaria hydropiper (L.) Spach (Marsh-pepper Smartweed, Water-pepper)
  • Persicaria hydropiperoides (Michx.) Small (Mild Water-pepper, Marsh-pepper Smartweed)
  • Persicaria lapathifolia (L.) Gray (Dock-leaf Smartweed, Pale Smartweed)
  • Persicaria longiseta (Bruijn) Kitagawa (Long-bristled Smartweed, Bristly Lady's-Thumb)
  • Persicaria maculosa Gray (Lady's-thumb, Spotted Lady's-thumb)
  • Persicaria orientalis (L.) Spach (Kiss-me-over-the-garden-gate, Prince's-feather, Prince's-plume)
  • Persicaria pensylvanica (L.) M. Gomez (Pennsylvania Smartweed, Pinkweed)
  • Persicaria perfoliata (L.) H. Gross (Mile-a-minute Weed, Mile-a-minute Vine, Asiatic Tearthumb)
  • Persicaria posumbu (Buch.-Ham. ex D. Don) H. Gross (Asian Lady's-thumb)
  • Persicaria punctata (Ell.) Small (Dotted Smartweed)
  • Persicaria robustior (Small) E.P. Bicknell (Stout Smartweed)
  • Persicaria sagittata (L.) H. Gross ex Nakai (Arrow-leaf Tearthumb)
  • Persicaria setacea (Baldw.) Small (Bog Smartweed, Swamp Smartweed)
  • Persicaria virginiana (L.) Gaertn. (Virginia Knotweed, Jumpseed)
  • Petrorhagia prolifera (L.) P.W. Ball & Heywood (Childing Pink, Proliferous Pink)
  • Petrorhagia saxifraga (L.) Link var. saxifraga (Saxifrage Pink)
  • Petunia atkinsiana Loudon
  • Phacelia bipinnatifida Michx. (Fernleaf Phacelia, Forest Phacelia)
  • Phacelia covillei S. Wats. ex A. Gray (Coville’s Phacelia)
  • Phacelia dubia (L.) Trel. var. dubia (Appalachian Phacelia)
  • Phacelia fimbriata Michx. (Fringed Phacelia, Fringed Scorpion-weed)
  • Phacelia purshii Buckl. (Miami-mist)
  • Phaeoceros carolinianus (Michx.) Prosk.
  • Phaeoceros laevis (L.) Prosk.
  • Phalaris arundinacea L. (Reed Canary Grass, Ribbon Grass)
  • Phalaris canariensis L. (Annual Canary Grass, Common Canary Grass, Birdseed Grass)
  • Phalaris caroliniana Walt. (Carolina Canary Grass, Maygrass)
  • Phanopyrum gymnocarpon (Ell.) Nash (Savanna Panic Grass, Clustered Panic Grass)
  • Phaseolus polystachios (L.) BSP (Wild Bean, Thicket Bean)
  • Phegopteris hexagonoptera (Michx.) Fee (Broad Beech Fern)
  • Phelipanche ramosa L. (Branching Broomrape, Hemp Broomrape)
  • Phellodendron amurense Ruprecht (Amur Cork-tree, Japanese Cork-tree)
  • Phemeranthus piedmontanus Ware (Piedmont Fameflower)
  • Phemeranthus teretifolius (Pursh) Raf. (Roundleaf Fameflower, Quill Fameflower, Appalachian Fameflower)
  • Philadelphus coronarius L. (Sweet Mock Orange)
  • Philadelphus hirsutus Nutt. (Hairy Mock Orange)
  • Philadelphus inodorus L. (Scentless Mock Orange)
  • Philadelphus pubescens Loisel. (Hoary Mock Orange)
  • Philonotis fontana (Hedw.) Brid. var. fontana (Fountain Moss)
  • Philonotis gracillima ngstrm
  • Philonotis longiseta (Michx.) E. Britton
  • Philonotis marchica (Hedw.) Brid.
  • Philonotis uncinata (Schwagr.) Bridel
  • Phleum pratense L. (Timothy)
  • Phlox amplifolia Britt. (Large-leaf Phlox)
  • Phlox buckleyi Wherry (Sword-leaf Phlox)
  • Phlox carolina L. (Carolina Phlox, Thick-leaf Phlox)
  • Phlox divaricata L. (Wild Blue Phlox, Woodland Phlox)
  • Phlox drummondii Hook. (Annual Phlox)
  • Phlox glaberrima L. (Smooth Phlox)
  • Phlox maculata L. (Meadow Phlox, Wild Sweet-william)
  • Phlox nivalis Lodd. ex Sweet ssp. hentzii (Nutt.) Wherry (Trailing Phlox)
  • Phlox ovata L. (Mountain Phlox, Appalachian Phlox)
  • Phlox paniculata L. (Fall Phlox, Garden Phlox)
  • Phlox pilosa L. ssp. pilosa (Downy Phlox)
  • Phlox stolonifera Sims (Creeping Phlox)
  • Phlox subulata L. (Moss Phlox, Moss-pink)
  • Phoradendron leucarpum (Raf.) Reveal & M.C. Johnston ssp. leucarpum (American Mistletoe, Eastern Mistletoe)
  • Photinia serratifolia (Desf.) Kalkm. (Taiwanese Photinia)
  • Phragmites americanus (Saltonstall P.M. Peterson, & Soreng) A. Haines (American Common Reed)
  • Phragmites australis (Cav.) Trin. ex Steud. (Common Reed)
  • Phryma leptostachya L. (Lopseed, American Lopseed)
  • Phyla lanceolata (Michx.) Greene (Frogfruit, Lance-leaf Frogfruit)
  • Phyla nodiflora (L.) Greene (Sawtooth Frogfruit, Turkey-tangle Frogfruit)
  • Phyllanthus caroliniensis Walt. ssp. caroliniensis (Carolina Leaf-flower)
  • Phyllostachys aurea Carr. ex A. & C. Riviere (Golden Bamboo)
  • Phyllostachys aureosulcata McClure (Yellowgroove Bamboo)
  • Phyllostachys bissetii McClure (Bisset's Bamboo)
  • Phyllostachys nigra (Lodd. ex Lindl.) Munro (Black Bamboo)
  • Physalis angulata L. (Cut-leaf Ground-cherry)
  • Physalis grisea (Waterfall) M. Martinez (Gray Ground-cherry)
  • Physalis heterophylla Nees (Clammy Ground-cherry)
  • Physalis longifolia Nuttall var. subglabrata (Mackenzie & Bush) Cronq. (Longleaf Ground-cherry)
  • Physalis philadelphica Lamarck (Tomatillo)
  • Physalis pubescens L. (Downy Ground-cherry)
  • Physalis virginiana P. Miller (Virginia Ground-cherry)
  • Physalis walteri Nutt. (Dune Ground-cherry)
  • Physaria gordonii (A. Gray) O'Kane & Al-Shehbaz (Gordon's Bladderpod)
  • Physcomitrella patens (Hedw.) Bruch & Schimp.
  • Physcomitrium collenchymatum Gier
  • Physcomitrium pyriforme (Hedw.) Hampe
  • Physocarpus opulifolius (L.) Maxim. var. opulifolius (Common Ninebark, Eastern Ninebark)
  • Physostegia leptophylla Small (Slender-leaf False Dragonhead)
  • Physostegia virginiana (L.) Benth. (Obedient-plant)
  • Phytolacca americana L. var. americana (Common Pokeweed)
  • Phytolacca americana L. var. rigida (Small) Caulkins & Wyatt (Seaside Pokeweed)
  • Picea abies (L.) H. Karsten (Norway Spruce)
  • Picea rubens Sargent (Red Spruce)
  • Picris hieracioides L. (Hawkweed Ox-tongue, Cat's-ear)
  • Pieris floribunda (Pursh) Benth. & Hook. f. (Evergreen Mountain Fetterbush, Mountain Andromeda)
  • Pilea fontana (Lunell) Rydb. (Lesser Clearweed, Blackfruit Clearweed)
  • Pilea microphylla (L.) Liebm. (Rockweed)
  • Pilea pumila (L.) Gray (Clearweed, Greenfruit Clearweed)
  • Pilosella aurantiaca (L.) F. Schultz & Schultz Bip. (Orange Hawkweed, Orange King-devil)
  • Pilosella caespitosa (Dum.) P.D. Sell & C. West (Meadow Hawkweed, Yellow King-devil)
  • Pilosella floribunda (Wimmer & Grabowski) Arvet-Touvet (Glaucous Hawkweed)
  • Pilosella officinarum F. Schultz & Schultz Bip. (Mouse-ear Hawkweed)
  • Pilosella piloselloides (Villars) Sojk (Tall Hawkweed)
  • Pimpinella saxifraga L. ssp. saxifraga (Burnet Saxifrage)
  • Pinellia ternata (Thunb.) Makino ex Breitenbach (Crow-dipper)
  • Pinus echinata Miller (Shortleaf Pine)
  • Pinus palustris Miller (Longleaf Pine)
  • Pinus pungens Lambert (Table-mountain Pine)
  • Pinus resinosa Aiton (Red Pine)
  • Pinus rigida Miller (Pitch Pine)
  • Pinus serotina Michaux (Pond Pine)
  • Pinus strobus L. (Eastern White Pine)
  • Pinus taeda L. (Loblolly Pine)
  • Pinus virginiana Miller (Virginia Pine, Scrub Pine)
  • Piptochaetium avenaceum (L.) Parodi (Eastern Needlegrass)
  • Pistacia chinensis Bunge (Chinese Pistachio)
  • Pistia stratiotes L. (Water Lettuce)
  • Pityopsis aspera (Shuttlw. ex Small) Small var. adenolepis (Fern.) Semple & Bowers (Pineland Golden-aster)
  • Pityopsis nervosa (Willd.) Dress (Grass-leaved Golden-aster)
  • Plagiochasma rupestre (J.R. Forst. & G. Forst.) Steph. var. rupestre
  • Plagiochila appalachiana Inoue
  • Plagiochila austinii A. Evans
  • Plagiochila echinata R.M. Schuster
  • Plagiochila exigua (Taylor) Taylor
  • Plagiochila porelloides (Torr. ex Nees) Lindenb.
  • Plagiochila raddiana Lindenb.
  • Plagiochila sullivantii Gottsche ex A. Evans
  • Plagiochila virginica A. Evans
  • Plagiomnium ciliare (Mll. Hal.) T.J. Kop.
  • Plagiomnium cuspidatum (Hedw.) T.J. Kop.
  • Plagiomnium drummondii (Bruch & Schimp.) T.J. Kop.
  • Plagiomnium ellipticum (Brid.) T.J. Kop.
  • Plagiomnium medium (Bruch & Schimp.) T.J. Kop.
  • Plagiomnium rostratum (Schrad.) T.J. Kop.
  • Plagiopus oederianus (Sw.) H.A. Crum & L.E. Anderson
  • Plagiothecium cavifolium (Brid.) Z. Iwats.
  • Plagiothecium denticulatum (Hedw.) Schimp.
  • Plagiothecium laetum Schimp.
  • Plagiothecium latebricola Bruch, Schimper, & W. Gmbel (Lurking Leskea)
  • Planodes virginicum (L.) E.L. Greene (Virginia Winged Rock Cress)
  • Plantago aristata Michxaux (Bracted Plantain, Large-bracted Plantain)
  • Plantago cordata Lamarck (King-root, Heart-leaved Plantain)
  • Plantago heterophylla Nuttall (Slender Plantain)
  • Plantago indica L. (Leafy-stemmed Plantain)
  • Plantago lanceolata L. (English Plantain, Rib-grass)
  • Plantago major L. (Common Plantain)
  • Plantago maritima L. var. juncoides (Lamarck) Gray (Seaside Plantain)
  • Plantago patagonica Jacquin (Woolly Plantain)
  • Plantago pusilla Nuttall (Dwarf Plantain)
  • Plantago rugelii Dcne. (American Plantain, Broad-leaved Plantain, Blackseed Plantain)
  • Plantago virginica L. (Virginia Plantain, Paleseed Plantain)
  • Plantago wrightiana Dcne. (Wright's Plantain)
  • Platanthera blephariglottis (Willd.) Lindl. (Small White Fringed Orchid)
  • Platanthera ciliaris (L.) Lindl. (Yellow Fringed Orchid)
  • Platanthera clavellata (Michx.) Luer (Small Green Wood Orchid)
  • Platanthera cristata (Michx.) Lindl. (Crested Fringed Orchid, Golden Fringed Orchid)
  • Platanthera flava (L.) Lindl. (Rein Orchid)
  • Platanthera flava (L.) Lindl. var. flava (Southern Rein Orchid, Southern Gypsy-spike)
  • Platanthera flava (L.) Lindl. var. herbiola (R.Br. ex Ait.f.) Luer (Tubercled Rein Orchid, Northern Gypsy-spike)
  • Platanthera grandiflora (Bigelow) Lindl. (Large Purple Fringed Orchid)
  • Platanthera hookeri (Torrey ex Gray) Lindley (Hooker's Orchid)
  • Platanthera lacera (Michx.) G. Don (Ragged Fringed Orchid, Green Fringed Orchid)
  • Platanthera leucophaea (Nutt.) Lindl. (Prairie Fringed Orchid)
  • Platanthera orbiculata (Pursh) Lindl. (Large Round-leaved Orchid)
  • Platanthera peramoena (Gray) Gray (Purple Fringeless Orchid, Purple Spire Orchid)
  • Platanthera psycodes (L.) Lindl. (Small Purple Fringed Orchid)
  • Platanthera shriveri P.M. Brown (Shriver's Frilly Orchid)
  • Platanus occidentalis L. (Sycamore, American Sycamore)
  • Platydictya confervoides (Brid.) H.A. Crum
  • Platydictya minutissima (Sull. & Lesq.) H.A. Crum
  • Platydictya subtilis (Hedw.) H.A. Crum (Algal Thread Moss)
  • Platygyrium repens (Brid.) Schimp.
  • Platylomella lescurii (Sull.) A. L. Andrews (Bordered Brook Moss)
  • Pleioblastus fortunei (Van Houtte) Nakai (Pygmy Bamboo, Dwarf Fern-leaf Bamboo)
  • Pleopeltis michauxiana (Weath.) Hickey & Sprunt (Resurrection Fern, Scaly Polypody)
  • Pleuridium acuminatum Lindb.
  • Pleuridium subulatum (Hedw.) Rabenh.
  • Pleuridium sullivantii Austin
  • Pleurochaete luteola (Besch.) Ther.
  • Pleurozium schreberi (Willd. ex Brid.) Mitt. (Phoenix Feather Moss, Big Red Stem)
  • Pluchea camphorata (L.) DC. (Camphorweed, Camphor Pluchea)
  • Pluchea foetida (L.) DC. var. foetida (Stinking Camphorweed)
  • Pluchea odorata (L.) Cass. (Salt Marsh Fleabane)
  • Poa alsodes Gray (Grove Bluegrass)
  • Poa annua L. (Annual Bluegrass)
  • Poa arachnifera Torr, (Texas Bluegrass)
  • Poa autumnalis Muhl. ex Ell. (Autumn Bluegrass)
  • Poa bulbosa L. ssp. vivipara (Koel.) Arcang. (Bulbous Bluegrass)
  • Poa chapmaniana Scribn. (Chapman's Bluegrass)
  • Poa compressa L. (Flat-stemmed Bluegrass)
  • Poa cuspidata Nutt. (Early Bluegrass, Short-leaved Bluegrass)
  • Poa iconia Azn. var. iconia
  • Poa languida Hitchc. (Drooping Bluegrass)
  • Poa nemoralis L. (Wood Bluegrass)
  • Poa paludigena Fern. & Wieg. (Bog Bluegrass)
  • Poa palustris L. (Fowl Bluegrass)
  • Poa pratensis L. (Kentucky Bluegrass)
  • Poa saltuensis Fern. & Wieg. (Weak Bluegrass)
  • Poa sylvestris Gray (Woodland Bluegrass)
  • Poa trivialis L. ssp. trivialis (Rough Bluegrass)
  • Podophyllum peltatum L. (Mayapple)
  • Podostemum ceratophyllum Michx. (Horn-leaf Riverweed, Threadfoot)
  • Pogonatum brachyphyllum (Michx.) P. Beauv.
  • Pogonatum pensilvanicum (Hedw.) P. Beauv. (Algal Haircap Moss)
  • Pogonia ophioglossoides (L.) Ker-Gawl. (Rose Pogonia)
  • Pohlia annotina (Hedw.) Lindb.
  • Pohlia camptotrachela (Renauld & Cardot) Broth.
  • Pohlia cruda (Hedw.) Lindb.
  • Pohlia elongata Hedwig
  • Pohlia lescuriana (Sullivant) Ochi
  • Pohlia longicolla (Hedwig) Lindberg
  • Pohlia melanodon (Brid.) A.J. Shaw
  • Pohlia nutans (Hedw.) Lindb.
  • Pohlia proligera (Kindb.) Lindb. ex Arnell
  • Pohlia wahlenbergii (F. Weber & D. Mohr) A.L. Andrews
  • Polanisia dodecandra (L.) A. DC. var. dodecandra (Common Clammy-weed)
  • Polanisia dodecandra (L.) A. DC. var. trachysperma (Torrey & A. Gray) Iltis (Western Clammy-weed)
  • Polemonium reptans L. var. reptans (Spreading Jacob's Ladder, Greek Valerian)
  • Polycarpon tetraphyllum (L.) L. (Four-leaf Manyseed)
  • Polygaloides paucifolia (Willd.) J.R. Abbott (Gaywings, Fringed Polygala)
  • Polygonatum biflorum (Walt.) Ell. (Solomon's-seal)
  • Polygonatum biflorum (Walt.) Ell. var. biflorum (Solomon's-seal)
  • Polygonatum biflorum (Walt.) Ell. var. commutatum (J.A. & J.H. Schultes) Morong (Large Solomon's-seal, King Solomon's-seal)
  • Polygonatum pubescens (Willd.) Pursh (Hairy Solomon's-seal, Downy Solomon's-seal)
  • Polygonella articulata (L.) Meisn. (Coastal Jointweed, Sand Jointweed)
  • Polygonella polygama (Vent.) Engelm. & Gray var. polygama (October-flower)
  • Polygonum aviculare L. (Prostrate Knotweed, Knotgrass)
  • Polygonum erectum L. (Erect Knotweed)
  • Polygonum glaucum Nutt. (Sea-beach Knotweed)
  • Polygonum ramosissimum Michx. (Bushy Knotweed)
  • Polygonum tenue Michx. (Slender Knotweed)
  • Polymnia canadensis L. (White-flowered Leafcup)
  • Polypodium appalachianum Haufler & Windham (Appalachian Rock Polypody, Appalachian Rockcap Fern)
  • Polypodium virginianum L. (Common Rock Polypody, Common Rockcap Fern)
  • Polypogon monspeliensis (L.) Desf. (Annual Rabbitfoot Grass)
  • Polypremum procumbens L. (Juniper-leaf, Rustweed, Polypremum)
  • Polystichum acrostichoides (Michx.) Schott (Christmas Fern)
  • Polytrichastrum alpinum (Hedw.) G. L. Sm. var. alpinum (Alpine Haircap Moss)
  • Polytrichastrum appalachianum (L. E. Anderson) G. L. Smith (Appalachian Haircap Moss)
  • Polytrichastrum formosum (Hedw.) G. L. Sm. var. densifolium (Mitten) Z. Iwatsuki & A. Noguchi
  • Polytrichastrum ohioense (Renauld & Cardot) G.L. Sm.
  • Polytrichastrum pallidisetum (Funck) G. L. Sm. (Mountain Haircap Moss)
  • Polytrichum commune Hedwig var. commune (Common Haircap Moss)
  • Polytrichum commune Hedwig var. perigoniale (Michx.) Hampe
  • Polytrichum juniperinum Hedwig (Juniper Haircap Moss)
  • Polytrichum piliferum Hedwig (Bristly Haircap Moss)
  • Polytrichum strictum Bridel (Woolly Haircap Moss)
  • Pontederia cordata L. var. cordata (Pickerelweed)
  • Ponthieva racemosa (Walt.) C. Mohr (Shadow Witch Orchid)
  • Populus alba L. (White Poplar, Silver Poplar)
  • Populus balsamifera L. (Balsam poplar)
  • Populus deltoides Bartram ex Marshall ssp. deltoides (Eastern Cottonwood)
  • Populus grandidentata Michx. (Bigtooth Aspen)
  • Populus heterophylla L. (Swamp Cottonwood)
  • Populus nigra L. (Lombardy Poplar, Black Cottonwood)
  • Populus tremuloides Michx. (Quaking Aspen)
  • Populus canadensis Moench
  • Populus canescens (Ait.) Sm. (Gray Poplar)
  • Populus jackii Sargent
  • Porella pinnata Linnaeus
  • Porella platyphylla (L.) Pfeiffer
  • Portulaca amilis Speg. (Paraguayan Purslane)
  • Portulaca grandiflora Hook. (Rose-moss)
  • Portulaca halimoides L. (Silkcotton purslane)
  • Portulaca oleracea L. (Common Purslane, Garden Purslane)
  • Portulaca pilosa L. (Kiss-me-quick)
  • Portulaca smallii P. Wilson (Small's Purslane)
  • Potamogeton amplifolius Tuckerman (Bigleaf Pondweed, Large-leaf Pondweed)
  • Potamogeton berchtoldii Fieber (Slender Pondweed)
  • Potamogeton bicupulatus Fernald (Snailseed Pondweed)
  • Potamogeton crispus L. (Curled Pondweed, Curly Pondweed)
  • Potamogeton diversifolius Raf. (Waterthread Pondweed, Common Snailseed Pondweed)
  • Potamogeton epihydrus Raf. (Ribbonleaf Pondweed)
  • Potamogeton foliosus Raf. var. foliosus (Leafy Pondweed)
  • Potamogeton friesii Ruprecht (Fries' Pondweed)
  • Potamogeton hillii Morong (Hill's Pondweed)
  • Potamogeton illinoensis Morong (Illinois pondweed)
  • Potamogeton nodosus L. (Longleaf Pondweed, American Pondweed)
  • Potamogeton oakesianus Robbins (Oakes' pondweed)
  • Potamogeton perfoliatus L. (Clasping-leaf Pondweed, Perfoliate Pondweed)
  • Potamogeton pulcher Tuckerman (Spotted Pondweed)
  • Potamogeton pusillus L. (Small Pondweed)
  • Potamogeton robbinsii Oakes (Flatleaf Pondweed, Fern Pondweed)
  • Potamogeton spirillus Tuckerman (Spiral Pondweed, Northern Snailseed Pondweed)
  • Potamogeton strictifolius Bennett (Straightleaf Pondweed)
  • Potamogeton tennesseensis Fernald (Tennessee Pondweed)
  • Potamogeton zosteriformis Fernald (Flatstem Pondweed)
  • Potentilla argentea L. (Silvery Cinquefoil)
  • Potentilla canadensis L. (Dwarf Cinquefoil, Canada Cinquefoil)
  • Potentilla indica (Andr.) T. Wolf (Indian-strawberry)
  • Potentilla intermedia L. (Downy Cinquefoil)
  • Potentilla norvegica L. (Rough Cinquefoil)
  • Potentilla recta L. (Sulphur Cinquefoil, Rough-fruited Cinquefoil)
  • Potentilla reptans L. (Creeping Cinquefoil, European Cinquefoil)
  • Potentilla rivalis Nutt. (Brook Cinquefoil)
  • Potentilla simplex Michx. (Common Cinquefoil)
  • Poterium sanguisorba L. var. polygamum (Waldstein & Kitaibel) Visiani (Salad Burnet, Garden Burnet)
  • Pourthiaea villosa (Thunb.) Decaisne (Smooth Oriental Photinia)
  • Primula meadia (L.) A. R. Mast & Reveal (Eastern Shooting Star)
  • Proboscidea louisianica (P. Miller) Thellung (Unicorn-plant, Devil's-claw)
  • Prosartes lanuginosa (Michx.) D. Don (Yellow Mandarin, Yellow Fairybells)
  • Prosartes maculata (Buckl.) Gray (Spotted Mandarin, Nodding Mandarin)
  • Proserpinaca palustris L. (Common Mermaid-weed)
  • Proserpinaca pectinata Lam. (Comb-leaf Mermaid-weed)
  • Prunella laciniata (L.) L. (Cutleaf Self-heal)
  • Prunella vulgaris L. (Self-heal, Heal-all)
  • Prunus alleghaniensis Porter var. alleghaniensis (Allegheny Plum, Allegheny Sloe)
  • Prunus americana Marshall (American Wild Plum)
  • Prunus angustifolia Marshall (Chickasaw Plum)
  • Prunus avium (L.) L. (Sweet Cherry, Bird Cherry)
  • Prunus caroliniana (P. Miller) Aiton (Carolina Laurel Cherry)
  • Prunus cerasifera Ehrh. (Cherry Plum)
  • Prunus cerasus L. (Sour Cherry)
  • Prunus domestica L. var. insititia (L.) Fiori & Paoletti (Damson Plum)
  • Prunus hortulana Bailey (Hortulan plum)
  • Prunus mahaleb L. (Mahaleb Cherry, Rock Cherry, Perfumed Cherry)
  • Prunus maritima Marshall (Beach Plum)
  • Prunus munsoniana W. Wight & Hedrick (Wild Goose Plum)
  • Prunus nigra Aiton (Canada Plum)
  • Prunus pensylvanica L.f. (Pin Cherry, Fire Cherry)
  • Prunus persica (L.) Batsch (Peach)
  • Prunus serotina Ehrhart ssp. serotina (Black Cherry, Wild Black Cherry)
  • Prunus subhirtella Miq. (Spring Cherry, Higan Cherry, Winter-flowering Cherry)
  • Prunus susquehanae Hort. ex Willd. (Susquehanna Sand Cherry)
  • Prunus virginiana L. var. virginiana (Choke Cherry)
  • Pseudobryum cinclidioides (Huebener) T.J. Kop.
  • Pseudocampylium radicale (P. Beauv.) Vanderpoorten & Hedens
  • Pseudognaphalium helleri (Britt.) A. Anderb. (Heller's Cudweed, Heller's Rabbit Tobacco)
  • Pseudognaphalium macounii (Greene) Kartesz (Clammy Everlasting, Winged Cudweed)
  • Pseudognaphalium micradenium (Weatherby) Nesom (Small Rabbit Tobacco, Delicate Rabbit Tobacco)
  • Pseudognaphalium obtusifolium (L.) Hilliard & Burtt (Sweet Everlasting, Catfoot, Rabbit Tobacco)
  • Pseudognaphalium stramineum (Kunth) W.A. Weber (Cotton-batting Plant)
  • Pseudolycopodiella caroliniana (L.) Holub (Carolina Bog Clubmoss, Slender Clubmoss)
  • Pseudosasa japonica (Sieb. & Zucc. ex Steud.) Makino ex Nakai (Arrow Bamboo)
  • Pseudotaxiphyllum distichaceum (Mitt.) Z. Iwats.
  • Pseudotaxiphyllum elegans (Brid.) Z. Iwats.
  • Ptelea trifoliata L. var. mollis Torr. & Gray (Hairy Hop-tree)
  • Ptelea trifoliata L. var. trifoliata (Hop-tree, Wafer-ash)
  • Pteridium aquilinum (L.) Kuhn (Bracken Fern)
  • Pteridium aquilinum (L.) Kuhn ssp. latiusculum (Desv.) Hulten (Eastern Bracken Fern)
  • Pteridium aquilinum (L.) Kuhn ssp. pseudocaudatum (Clute) Hulten (Southern Bracken Fern)
  • Pterigynandrum filiforme Hedwig
  • Pteris multifida Poir. (Spider Fern)
  • Ptilidium pulcherrimum (Weber) Vain.
  • Ptilimnium capillaceum (Michx.) Raf. (Mock Bishop's-weed)
  • Ptilium crista-castrensis (Hedw.) De Not. (Knight's Plume Moss)
  • Ptychomitrium drummondii (Wilson) Sull.
  • Ptychomitrium incurvum (Schwgr.) Spruce
  • Ptychostomum creberrimum (Taylor) J.R. Spence & H.P. Ramsay (Scarlet Stalk Moss)
  • Ptychostomum intermedium (Brid.) J.R. Spence
  • Ptychostomum pallescens (Schleicher ex Schwgr.) J.R. Spence
  • Ptychostomum pseudotriquetrum (Hedw.) J.R. Spence & H.P. Ramsay ex Holyoak & N. Pedersen
  • Ptychostomum weigelii (Sprengel) J.R. Spence
  • Puccinellia distans (Jacq.) Parl. (European Alkali Grass)
  • Puccinellia fasciculata (Torr.) Bickn. (Eastern Alkali Grass, Saltmarsh Goosegrass)
  • Pueraria montana (Loureiro) Merritt var. lobata (Willd.) Maesen & S. Almeida (Kudzu)
  • Pycnanthemum beadlei (Small) Fern. (Beadle's Mountain-mint)
  • Pycnanthemum clinopodioides Torr. & Gray (Basil Mountain-mint)
  • Pycnanthemum curvipes (Greene) Grant & Epling (Tennessee Mountain-mint)
  • Pycnanthemum flexuosum (Walt.) B.S.P. (Savanna Mountain-mint, Hyssop-leaf Mountain-mint)
  • Pycnanthemum incanum (L.) Michx. var. incanum (Hoary Mountain-mint)
  • Pycnanthemum incanum complex (Hoary Mountain-mint)
  • Pycnanthemum loomisii Nutt. (Loomis' Mountain-mint)
  • Pycnanthemum monotrichum Fern. (One-hair Mountain-mint)
  • Pycnanthemum muticum (Michx.) Pers. (Short-toothed Mountain-mint, Clustered Mountain-mint)
  • Pycnanthemum pycnanthemoides (Leavenworth) Fern. (Southern Mountain-mint)
  • Pycnanthemum setosum Nutt. (Awned Mountain-mint)
  • Pycnanthemum tenuifolium Schrad. (Narrow-leaf Mountain-mint, Slender Mountain-mint)
  • Pycnanthemum torreyi Benth. (Torrey's Mountain-mint)
  • Pycnanthemum verticillatum (Michx.) Pers. (Whorled Mountain-mint)
  • Pycnanthemum virginianum (L.) T. Dur. & B.D. Jackson ex B.L. Robins. & Fern. (Virginia Mountain-mint)
  • Pylaisia condensata (Mitt.) A. Jaeger (Paintbrush Moss)
  • Pylaisia intricata (Hedw.) Schimp.
  • Pylaisia polyantha (Hedw.) Schimp.
  • Pylaisiadelpha tenuirostris (Bruch & Schimp. ex Sull.) W.R. Buck
  • Pyracantha coccinea M. Roemer (Scarlet Firethorn)
  • Pyrola americana Sweet (Round-leaved Pyrola, American Wintergreen)
  • Pyrola chlorantha Sw. (Green Pyrola, Green-flowered Wintergreen)
  • Pyrola elliptica Nutt. (Shinleaf, Wax-flower Shinleaf)
  • Pyrrhopappus carolinianus (Walt.) DC. (Carolina False Dandelion)
  • Pyrularia pubera Michx. (Buffalo-nut, Oil-nut)
  • Pyrus calleryana Dcne. (Callery Pear)
  • Pyrus communis L. (Common Pear)
  • Pyrus elaeagnifolia Pallas? (Oleaster-leaved Pear)
  • Pyrus pyrifolia (Burm. f.) Nakai (Chinese Pear, Asian Pear)
  • Pyxidanthera barbulata Michx. var. barbulata (Common Pyxie-moss, Flowering Pyxie-moss, Big Pyxie)
  • Quercus acutissima Carruthers (Sawtooth Oak)
  • Quercus alba Linnaeus (White Oak)
  • Quercus bicolor Willdenow (Swamp White Oak)
  • Quercus coccinea Muenchhausen (Scarlet Oak)
  • Quercus falcata Michaux (Southern Red Oak, Spanish Oak)
  • Quercus hemisphaerica Bartram ex Willdenow (Sand Laurel Oak, Darlington Oak)
  • Quercus ilicifolia Wangenheim (Bear Oak, Scrub Oak)
  • Quercus imbricaria Michaux (Shingle Oak)
  • Quercus incana W. Bartram (Bluejack Oak)
  • Quercus laevis Walter (Turkey Oak)
  • Quercus laurifolia Michaux (Laurel Oak)
  • Quercus lyrata Walter (Overcup Oak)
  • Quercus macrocarpa Michaux (Bur Oak, Mossycup Oak)
  • Quercus margarettae Ashe ex Small (Sand Post Oak)
  • Quercus marilandica Muenchhausen var. marilandica (Blackjack Oak)
  • Quercus michauxii Nuttall (Swamp Chestnut Oak, Basket Oak)
  • Quercus montana Willd. (Chestnut Oak, Rock Chestnut Oak)
  • Quercus muehlenbergii Engelmann (Chinquapin Oak, Chinkapin Oak, Yellow Oak)
  • Quercus nigra Linnaeus (Water Oak)
  • Quercus pagoda Rafinesque (Cherrybark Oak, Swamp Spanish Oak)
  • Quercus palustris Muenchhausen (Pin Oak)
  • Quercus phellos Linnaeus (Willow Oak)
  • Quercus prinoides Willdenow (Dwarf Chinquapin Oak, Dwarf Chinkapin Oak)
  • Quercus rubra L. var. borealis (F. Michaux) Farwell (Northern Red Oak)
  • Quercus rubra Linnaeus var. rubra (Northern Red Oak)
  • Quercus shumardii Buckley (Shumard Oak)
  • Quercus stellata Wangenheim (Post Oak)
  • Quercus velutina Lamarck (Black Oak)
  • Quercus virginiana Miller (Live Oak)
  • Radula australis Austin
  • Radula complanata (L.) Dumort.
  • Radula obconica Sullivant
  • Radula quadrata Gottsche
  • Radula tenax Lindberg
  • Ranunculus abortivus L. (Kidneyleaf Buttercup)
  • Ranunculus acris L. (Tall Buttercup, Bitter Buttercup)
  • Ranunculus allegheniensis Britt. (Allegheny Buttercup, Mountain Crowfoot)
  • Ranunculus ambigens S. Wats. (Water-plantain Crowfoot, Water-plantain Spearwort)
  • Ranunculus aquatilis L. var. diffusus Withering (Long-beaked Buttercup, White Water Crowfoot)
  • Ranunculus bulbosus L. (Bulbous Buttercup)
  • Ranunculus caricetorum Greene (Northern Swamp Buttercup, Marsh Buttercup)
  • Ranunculus fascicularis Muhl. ex Bigelow (Thick-root Buttercup, Early Buttercup)
  • Ranunculus flabellaris Raf. (Yellow Water Crowfoot)
  • Ranunculus hederaceus L. (Ivy-leaved Water Crowfoot, Long-stalked Crowfoot)
  • Ranunculus hispidus Michx. (Bristly Buttercup, Hispid Buttercup)
  • Ranunculus laxicaulis (Torr. & Gray) Darby (Mississippi Buttercup)
  • Ranunculus micranthus Nutt. (Rock Buttercup)
  • Ranunculus parviflorus L. (Small-flowered Buttercup, Stick-seed Crowfoot)
  • Ranunculus pusillus Poir. (Low Spearwort)
  • Ranunculus recurvatus Poir. var. recurvatus (Hooked Buttercup, Hooked Crowfoot)
  • Ranunculus repens L. (Creeping Buttercup)
  • Ranunculus sardous Crantz (Hairy Buttercup)
  • Ranunculus sceleratus L. var. sceleratus (Cursed Buttercup, Celery-leaved Crowfoot)
  • Ranunculus septentrionalis Poir. (Carolina Buttercup)
  • Raphanus raphanistrum L. (Wild Radish, Jointed Charlock, White Charlock)
  • Raphanus sativus Linnaeus (Radish)
  • Rapistrum rugosum (Linnaeus) Allioni (Annual Bastard Cabbage)
  • Ratibida pinnata (Vent.) Barnh. (Gray-headed Coneflower)
  • Rauiella scita (P. Beauv.) Reimers
  • Reboulia hemisphaerica (L.) Raddi
  • Reynoutria japonica Houttuyn var. japonica (Japanese Knotweed)
  • Reynoutria sachalinensis (F. Schmidt ex Maximowicz) Nakai (Giant Knotweed)
  • Rhabdoweisia crispata (Dicks. ex With.) Lindb.
  • Rhamnus cathartica L. (Common Buckthorn)
  • Rhamnus davurica Pallas (Dahurian Buckthorn)
  • Rhamphospermum arvense (L.) Al-Shehbaz (Charlock)
  • Rhamphospermum nigrum (L.) Al-Shehbaz (Black Mustard, Charlock)
  • Rhexia mariana L. var. mariana (Maryland Meadow Beauty, Pale Meadow Beauty)
  • Rhexia nashii Small (Hairy Meadow Beauty)
  • Rhexia petiolata Walt. (Fringed Meadow Beauty)
  • Rhexia ventricosa Fernald & Griscom (Swollen Meadow Beauty)
  • Rhexia virginica L. (Virginia Meadow Beauty)
  • Rhizomnium appalachianum T. J. Kop.
  • Rhizomnium magnifolium (Horik.) T.J. Kop.
  • Rhizomnium punctatum (Hedw.) T.J. Kop.
  • Rhodobryum ontariense (Kindb.) Kindb. (Rose Moss)
  • Rhododendron arborescens (Pursh) Torrey (Smooth Azalea, Sweet Azalea)
  • Rhododendron atlanticum (Ashe) Rehder (Dwarf Azalea)
  • Rhododendron calendulaceum (Michx.) Torr. (Flame Azalea)
  • Rhododendron catawbiense Michx. (Catawba Rhododendron, Mountain Rosebay, Pink Laurel)
  • Rhododendron cumberlandense E.L. Braun (Cumberland Azalea)
  • Rhododendron maximum L. (Great Rhododendron, White Rosebay, Great Laurel)
  • Rhododendron minus Michx. (Gorge Rhododendron)
  • Rhododendron periclymenoides (Michx.) Shinners (Wild Azalea, Pinxterflower, Pinxterbloom Azalea)
  • Rhododendron pilosum (Michx.) Craven (Minniebush)
  • Rhododendron prinophyllum (Small) Millais (Early Azalea, Rose Azalea, Roseshell Azalea)
  • Rhododendron viscosum (L.) Torr. var. serrulatum (Small) H.E. Ahles (Southeastern Swamp Azalea, Southeastern Clammy Azalea)
  • Rhododendron viscosum (L.) Torr. var. viscosum (Swamp Azalea, Clammy Azalea)
  • Rhodotypos scandens (Thunb.) Makino (Jetbead)
  • Rhus aromatica Aiton var. aromatica (Fragrant Sumac)
  • Rhus copallinum L. var. copallinum (Winged Sumac, Shining Sumac)
  • Rhus copallinum L. var. latifolia Engler (Winged Sumac, Shining Sumac)
  • Rhus glabra L. (Smooth Sumac)
  • Rhus michauxii Sargent (Michaux's Sumac, Dwarf Sumac)
  • Rhus typhina L. (Staghorn Sumac)
  • Rhynchosia difformis (Ell.) DC. (Climbing Snoutbean, Double-form Snoutbean)
  • Rhynchosia tomentosa (L.) Hook. & Arnott (Hairy Snoutbean)
  • Rhynchospora alba (L.) Vahl (Northern White Beaksedge)
  • Rhynchospora caduca Elliott (Angle-stem Beaksedge)
  • Rhynchospora capillacea Torrey (Needle Beaksedge)
  • Rhynchospora capitellata (Michaux) Vahl (Brownish Beaksedge)
  • Rhynchospora cephalantha A. Gray var. attenuata Gale (Small Bunched Beaksedge)
  • Rhynchospora cephalantha A. Gray var. cephalantha (Common Bunched Beaksedge)
  • Rhynchospora chalarocephala Fernald and Gale (Loose-headed Beaksedge)
  • Rhynchospora colorata (L.) H. Pfeiffer (Narrow-leaf Whitetop Sedge)
  • Rhynchospora corniculata (Lam.) Gray (Short-bristled Horned Beaksedge)
  • Rhynchospora debilis Gale (Savanna Beaksedge)
  • Rhynchospora distans (Michx.) Vahl. (Fasciculate Beaksedge)
  • Rhynchospora fascicularis (Michaux) Vahl (Fasciculate Beaksedge)
  • Rhynchospora filifolia Gray (Thread-leaved Beaksedge)
  • Rhynchospora globularis (Chapman) Small (Globe Beaksedge)
  • Rhynchospora glomerata (L.) Vahl (Clustered Beaksedge)
  • Rhynchospora gracilenta Gray (Slender Beaksedge)
  • Rhynchospora grayi Kunth (Gray's Beaksedge)
  • Rhynchospora harveyi W. Boott (Harvey's Beaksedge)
  • Rhynchospora inexpansa (Michaux) Vahl (Nodding Beaksedge)
  • Rhynchospora macrostachya Torrey ex Gray (Horned Beaksedge)
  • Rhynchospora microcephala (Britton) Britton ex Small (Small-headed Bunched Beaksedge)
  • Rhynchospora miliacea (Lam.) Gray (Millet Beaksedge)
  • Rhynchospora nitens (Vahl) Gray (Short-beaked Beaksedge)
  • Rhynchospora oligantha Gary (Feather-bristled Beaksedge)
  • Rhynchospora pallida M.A. Curtis (Pale Beaksedge)
  • Rhynchospora perplexa Britton in J.K. Small (Pineland Beaksedge)
  • Rhynchospora rariflora (Michaux) Elliott (Few-flowered Beaksedge)
  • Rhynchospora recognita (Gale) Kral (Round-headed Beaksedge, Cymose Beaksedge)
  • Rhynchospora scirpoides (Torrey) Grisebach (Long-beaked Beaksedge)
  • Rhynchospora stenophylla Chapman (Coastal Bog Beaksedge)
  • Rhynchospora torreyana Gray (Torrey's Beaksedge)
  • Rhynchospora wrightiana Boeckl. (Wright's Beaksedge)
  • Rhynchostegium serrulatum (Hedw.) A. Jaeger
  • Rhytidiadelphus subpinnatus (Lindb.) T.J. Koponen
  • Rhytidiadelphus triquetrus (Hedw.) Warnst.
  • Rhytidium rugosum (Hedw.) Kindb.
  • Ribes americanum P.Mill. (Wild Black Currant, American Black Currant)
  • Ribes cynosbati L. (Prickly Gooseberry)
  • Ribes glandulosum Grauer (Skunk Currant)
  • Ribes missouriense Nutt. (Missouri Gooseberry)
  • Ribes rotundifolium Michx. (Appalachian Gooseberry)
  • Ribes rubrum L. (Garden Red Currant)
  • Ribes uva-crispa var. sativum DC (European Gooseberry)
  • Riccardia chamedryfolia (With.) Grolle
  • Riccardia latifrons Lindberg ssp. latifrons
  • Riccardia multifida (L.) Gray
  • Riccardia palmata (Hedw.) Carruth.
  • Riccia beyrichiana Hampe ex Lehm.
  • Riccia cavernosa Hoffm.
  • Riccia dictyospora M. Howe
  • Riccia fluitans Linnaeus
  • Riccia hirta (Austin) Underw.
  • Riccia huebeneriana Lindenb. subsp. sullivantii (Austin) R.M. Schust.
  • Riccia membranacea Gottsche, Lindenb. & Nees
  • Riccia sorocarpa Bischoff
  • Ricciocarpos natans (L.) Corda
  • Richardia brasiliensis Gomes (Tropical Mexican-clover)
  • Richardia scabra L. (Rough Mexican-clover, Florida Pusley)
  • Ricinus communis L. (Castor Bean)
  • Ripariosida hermaphrodita (L.) Weakley & Poindexter (Virginia Sida, Virginia Mallow)
  • Robinia hispida L. (Bristly Locust)
  • Robinia pseudoacacia L. (Black Locust)
  • Robinia viscosa Vent. (Clammy Locust)
  • Rorippa austriaca (Crantz) Besser (Austrian Yellow Cress)
  • Rorippa indica (L.) Hiern. (Variable-leaf Yellow Cress)
  • Rorippa palustris (L.) Besser ssp. palustris (Marsh Yellow Cress)
  • Rorippa palustris (L.) Besser ssp. hispida (Desv.) Jonsell (Hairy Marsh Yellow Cress)
  • Rorippa sessiliflora (Nutt.) A.S. Hitchc. (Stalkless Yellow Cress, Sessile-flowered Yellow Cress)
  • Rorippa sylvestris (Linnaeus) Besser (Creeping Yellow Cress)
  • Rosa blanda Aiton (Smooth Rose, Meadow Rose)
  • Rosa bracteata J.C. Wendl. (Chickasaw Rose)
  • Rosa canina L. (Dog Rose)
  • Rosa carolina L. ssp. carolina (Carolina Rose, Pasture Rose)
  • Rosa carolina L. ssp. subserrulata (Rydb.) W.H. Lewis (Carolina Rose)
  • Rosa cinnamomea L. (Cinnamon Rose)
  • Rosa gallica L. (French Rose)
  • Rosa luciae Franchet & Rochebrune ex Crepin (Memorial Rose, Dorothy Perkins Rose, Lucie Rose)
  • Rosa multiflora Thunb. ex Murr. (Multiflora Rose)
  • Rosa palustris Marsh. (Swamp Rose)
  • Rosa rubiginosa L. var. nemoralis (Leman) Thory (Sweetbriar)
  • Rosa rubiginosa L. var. rubiginosa (Eglantine Rose)
  • Rosa rugosa Thunb. (Japanese Rose)
  • Rosa setigera Michx. (Prairie Rose, Climbing Prairie Rose)
  • Rosa spinosissima L. (Scotch Rose)
  • Rosa virginiana Miller (Virginia Rose)
  • Rosulabryum capillare (Hedw.) J.R. Spence (Cluster Moss)
  • Rosulabryum laevifilum (Syed) Ochyra
  • Rotala ramosior (L.) Koehne (Toothcup)
  • Rottboellia cochinchinensis (Lour.) Clayton (Itchgrass)
  • Rubacer odoratum (L.) Rydb. (Flowering Raspberry, Purple-flowering Raspberry)
  • Rubus allegheniensis Porter (Allegheny Blackberry)
  • Rubus bifrons Vest (European Blackberry, Himalayan Blackberry)
  • Rubus canadensis L. (Smooth Blackberry, Thornless Blackberry)
  • Rubus cuneifolius Pursh (Sand Blackberry)
  • Rubus flagellaris Willd. (Common Dewberry)
  • Rubus hispidus L. (Bristly Dewberry, Swamp Dewberry)
  • Rubus idaeus L. ssp. strigosus (Michx.) Focke (Red Raspberry)
  • Rubus laciniatus Willd. (Cut-leaved Blackberry, Evergreen Blackberry)
  • Rubus occidentalis L. (Black Raspberry)
  • Rubus pensilvanicus Poir. (Pennsylvania Blackberry, Prickly Blackberry)
  • Rubus phoenicolasius Maxim. (Wineberry)
  • Rubus setosus Bigelow (Bristly Blackberry)
  • Rubus trivialis Michx. (Southern Dewberry)
  • Rudbeckia fulgida Ait. var. fulgida (Orange Coneflower)
  • Rudbeckia fulgida Ait. var. umbrosa (C.L. Boynt. & Beadle) Cronq. (Appalachian Coneflower)
  • Rudbeckia heliopsidis Torr. & Gray (Sun-facing Coneflower)
  • Rudbeckia hirta L. var. hirta (Woodland Black-eyed Susan)
  • Rudbeckia hirta L. var. pulcherrima Farwell (Black-eyed Susan)
  • Rudbeckia laciniata L. (Cut-leaf Coneflower, Common Cut-leaf Coneflower, Green-headed Coneflower)
  • Rudbeckia laciniata L. var. bipinnata Perdue
  • Rudbeckia laciniata L. var. digitata (Mill.) Fiori (Southeastern Cut-leaf Coneflower)
  • Rudbeckia laciniata L. var. laciniata (Common Cut-leaf Coneflower)
  • Rudbeckia triloba L. var. beadlei (Small) Fernald (Pinnate-lobed Coneflower)
  • Rudbeckia triloba L. var. triloba (Three-lobed Coneflower, Brown-eyed Susan)
  • Ruellia caroliniensis (Gmelin) Steudel (Carolina Wild-petunia, Common Wild-petunia)
  • Ruellia humilis Nuttall (Low Wild-petunia, Hairy Wild-petunia)
  • Ruellia purshiana Fernald (Pursh's Wild-petunia)
  • Ruellia strepens L. (Smooth Wild-petunia, Limestone Wild-petunia)
  • Rumex altissimus Wood (Pale Dock, Tall Dock)
  • Rumex conglomeratus Murr. (Clustered Dock, Clustered Green Dock)
  • Rumex crispus L. ssp. crispus (Curly Dock)
  • Rumex obtusifolius L. (Bitter Dock, Broad-leaf Dock)
  • Rumex pulcher L. (Fiddle Dock)
  • Rumex verticillatus L. (Swamp Dock)
  • Ruppia maritima L. (Wigeon-grass, Ditch-grass)
  • Ruta graveolens L. (Rue)
  • Sabatia angularis (L.) Pursh (Rose-pink)
  • Sabatia brachiata Ell. (Narrow-leaf Rose-pink, Narrow-leaf Rose-gentian)
  • Sabatia calycina (Lam.) Heller (Coastal Rose-pink, Coastal Rose-gentian)
  • Sabatia campanulata (L.) Torr. (Slender Marsh-pink, Slender Rose-gentian)
  • Sabatia difformis (L.) Druce (Lance-leaved Rose-gentian)
  • Sabatia dodecandra (L.) BSP (Large Marsh-pink, Marsh Rose-gentian)
  • Sabatia quadrangula Wilbur (Four-angle Rose-gentian, Winged Sabatia)
  • Sabatia stellaris Pursh (Salt-marsh Pink, Sea-pink)
  • Sabulina diffusa Brock
  • Sabulina michauxii (Fenzl) Dillenberger & Kadereit (Rock Sandwort, Michaux's Stitchwort)
  • Sabulina paludicola (Fern. & B.G. Schub.) E.E. Schilling (Godfrey's Sandwort)
  • Sabulina patula (Michaux) Small (Pitcher's Stitchwort, Glade Sandwort)
  • Sacciolepis striata (L.) Nash (American Cupscale)
  • Sagina decumbens (Ell.) Torrey & A. Gray ssp. decumbens (Trailing Pearlwort)
  • Sagina procumbens L. (Matted Pearlwort)
  • Sagittaria australis (J.G.Smith) Small (Long-beaked Arrowhead)
  • Sagittaria brevirostra Mackenzie & Bush (Midwestern Arrowhead)
  • Sagittaria calycina Engelm. (Long-lobed Arrowhead)
  • Sagittaria engelmanniana J.G. Smith (Engelmann's Arrowhead)
  • Sagittaria filiformis J.G. Smith (Narrow-leaved Arrowhead)
  • Sagittaria graminea Michaux (Grass-leaved Arrowhead)
  • Sagittaria lancifolia L. var. media Micheli (Lance-leaved Arrowhead, Bull-tongue Arrowhead)
  • Sagittaria latifolia Willd. var. latifolia (Broadleaf Arrowhead)
  • Sagittaria latifolia Willd. var. pubescens (Muhl. ex Nutt.) J.G. Smith (Hairy Arrowhead)
  • Sagittaria latifolia Willdenow (Broad-leaved Arrowhead, Duck Potato, Wapato)
  • Sagittaria platyphylla (Engelm.)J.G.Sm. (Delta Arrowhead)
  • Sagittaria rigida Pursh (Sessile-fruited Arrowhead)
  • Sagittaria spatulata (J.G. Smith) Buchenau (Tidal Arrowhead)
  • Sagittaria subulata (L.) Buch. (Dwarf Arrowhead)
  • Sagittaria weatherbiana Fernald (Weatherby's Arrowhead)
  • Salicornia ambigua Michaux (Woody Glasswort, Perennial Glasswort)
  • Salicornia bigelovii Torr. (Dwarf Glasswort, Dwarf Saltwort)
  • Salicornia virginica L. (Jointed Glasswort)
  • Salix alba L. (White Willow)
  • Salix babylonica L. (Weeping Willow)
  • Salix caprea L. (Goat Willow)
  • Salix caroliniana Michx. (Carolina Willow, Coastal Plain Willow)
  • Salix cinerea L. (European Gray Willow)
  • Salix discolor Muhl. (Pussy Willow)
  • Salix eriocephala Michx. (Heart-leaved Willow)
  • Salix humilis Marshall (Prairie Willow, Upland Willow)
  • Salix interior Rowlee (Sandbar Willow)
  • Salix lucida Muhl. (Shining Willow)
  • Salix matsudana Koidzumi (Corkscrew Willow)
  • Salix nigra Marsh. (Black Willow)
  • Salix occidentalis Walter (Dwarf Upland Willow, Sage Willow)
  • Salix pentandra L. (Laurel Willow)
  • Salix purpurea L. (Basket Willow, Purple Willow, Purple Osier)
  • Salix sericea Marsh. (Silky Willow)
  • Salix bebbii Gandog.
  • Salix ehrhartiana Sm.
  • Salix fragilis L. (Crack Willow, Brittle Willow)
  • Salix sepulcralis Simonkai
  • Salpichroa origanifolia (Lam.) Baill. (Lily-of-the-valley Vine, Pampas Lily-of-the-valley)
  • Salsola kali L. (Saltwort)
  • Salsola tragus L. (Russian Thistle, Tumbleweed)
  • Salvia lyrata L. (Lyre-leaf Sage)
  • Salvia officinalis L. (Garden Sage)
  • Salvia pratensis L. (Meadow Sage, Meadow Clary)
  • Salvia reflexa Hornemann (Lanceleaf Sage)
  • Salvia sclarea L. (Clary Sage)
  • Salvia urticifolia L. (Nettle-leaf Sage)
  • Salvia verbenacea L. (Wild Clary Sage, Vervain Sage)
  • Salvinia molesta D.S. Mitchell (Giant Salvinia)
  • Sambucus canadensis L. (Common Elderberry)
  • Sambucus racemosa L. var. pubens (Michx.) Koehne (Red Elderberry)
  • Samolus parviflorus Raf. (Water-pimpernel, Brookweed)
  • Sanguinaria canadensis L. (Bloodroot)
  • Sanguisorba canadensis L. (Canada Burnet, American Burnet)
  • Sanicula canadensis L. var. canadensis (Black Snakeroot)
  • Sanicula canadensis L. var. floridana (Bicknell) H. Wolff (Florida Snakeroot)
  • Sanicula canadensis L. var. grandis Fern. (Large Sanicle)
  • Sanicula marilandica L. (Sanicle)
  • Sanicula odorata (Raf.) K.M. Pryer & L.R. Phillippe (Clustered Snakeroot)
  • Sanicula smallii Bickn. (Small's Snakeroot, Small's Sanicle)
  • Sanicula trifoliata Bickn. (Large-fruited Sanicle)
  • Saponaria officinalis L. (Soapwort, Bouncing Bet)
  • Sarracenia flava L. (Yellow Pitcher Plant, Trumpets)
  • Sarracenia purpurea L. (Purple Pitcher Plant)
  • Sassafras albidum (Nutt.) Nees (Sassafras)
  • Saururus cernuus L. (Lizard's-tail, Water-dragon)
  • Scapania degenii Schiffn. ex Mll. Frib. var. dubia R.M. Schuster
  • Scapania irrigua (Nees) Nees
  • Scapania nemorea (L.) Grolle
  • Scapania undulata (L.) Dumort.
  • Sceptridium biternatum (Savigny) Lyon (Southern Grape Fern)
  • Sceptridium dissectum (Sprengel) Lyon (Cut-leaf Grape Fern, Dissected Grape Fern)
  • Sceptridium jenmanii (Underwood) Lyon (Alabama Grape Fern)
  • Sceptridium multifidum (S.G. Gmelin) M. Nishida (Leathery Grape Fern)
  • Sceptridium oneidense (Gilbert) Holub (Blunt-lobed Grape Fern)
  • Schenkia spicata (L.) Mansion (Spiked Centaury)
  • Schistidium agassizii Sull. & Lesq.
  • Schistidium apocarpum (Hedw.) Bruch & Schimp.
  • Schistidium canadense (Dupr.) Ignatova & H.H. Blom
  • Schistidium crassithecium H. H. Blom ex B. H. Allen
  • Schistidium dupretii (Thr.) W.A. Weber
  • Schistidium liliputanum (Mll. Hal.) Deguchi
  • Schistidium rivulare (Brid.) Podp.
  • Schistidium sp. A.
  • Schistidium viride H. H. Blom & C. Darigo
  • Schistochilopsis incisa (Schrad.) Konstant.
  • Schizachne purpurascens (Torr.) Swallen (Purple Oatgrass, False Melic)
  • Schizachyrium littorale (Nash) E.P. Bicknell (Seaside Little Bluestem)
  • Schizachyrium scoparium (Michx.) Nash var. scoparium (Little Bluestem)
  • Schlotheimia rugifolia (Hook.) Schwgr.
  • Schoenoplectiella purshiana (Fernald) K. Lye var. purshiana (Blunt-scale Bulrush, Weak-stalk Bulrush)
  • Schoenoplectiella smithii (Fernald) Hayasaka (Smith's Bulrush, Blunt-scale Bulrush)
  • Schoenoplectus acutus (Muhl. ex Bigel.) Love & Love var. acutus (Hard-stem Bulrush, Great Bulrush)
  • Schoenoplectus americanus (Pers.) Volk. ex Schinz & Keller (Olney Threesquare)
  • Schoenoplectus etuberculatus (Steudel) Sojak (Swamp Bulrush, Canby's Bulrush)
  • Schoenoplectus mucronatus (L.) Palla (Bog Bulrush)
  • Schoenoplectus pungens (Vahl) Palla var. pungens (Common Threesquare, Chairmaker's Rush)
  • Schoenoplectus subterminalis (Torrey) Sojak (Water Bulrush)
  • Schoenoplectus tabernaemontani (Gmelin) Palla (Soft-stem Bulrush)
  • Schoenoplectus torreyi (Olney) Palla (Torrey's Bulrush, Torrey's Threesquare)
  • Schwalbea americana L. (Chaffseed)
  • Schwetschkeopsis fabronia (Schwgr.) Broth.
  • Scirpus ancistrochaetus Schuyler (Northeastern Bulrush)
  • Scirpus atrovirens Willd. (Dark Green Bulrush)
  • Scirpus cyperinus (L.) Kunth (Woolgrass)
  • Scirpus divaricatus Elliott (Spreading Bulrush)
  • Scirpus expansus Fernald (Woodland Bulrush)
  • Scirpus flaccidifolius (Fernald) Schuyler (Reclining Bulrush)
  • Scirpus georgianus Harper (Georgia Bulrush)
  • Scirpus hattorianus Makino (Northern Bulrush)
  • Scirpus lineatus Michaux (Drooping Bulrush)
  • Scirpus pendulus Muhlenberg (Reddish Bulrush)
  • Scirpus polyphyllus Vahl (Leafy Bulrush)
  • Sciuro-hypnum plumosum (Hedw.) Ignatov & Huttunen
  • Sciuro-hypnum populeum (Hedw.) Ignatov & Huttunen
  • Sciuro-hypnum reflexum (Starke) Ignatov & Huttunen
  • Scleranthus annuus L. ssp. annuus (Knawel, Annual Knawel)
  • Scleria ciliata Michaux var. ciliata (Hairy Nutrush, Fringed Nutrush)
  • Scleria ciliata Michaux var. elliottii (Chapman) Fernald (Broad-leaved Hairy Nutrush)
  • Scleria flaccida Steud. (Flaccid Nutrush)
  • Scleria minor (Britton) W. Stone (Slender Nutrush)
  • Scleria muehlenbergii Steudel (Pitted Nutrush)
  • Scleria nitida Willd. (Shining Nutrush)
  • Scleria oligantha Michaux (Little-headed Nutrush, Few-Flowered Nutrush)
  • Scleria pauciflora Muhl. ex Willd. (Carolina Nutrush, Papillose Nutrush)
  • Scleria pauciflora Muhl. ex Willd. var. caroliniana A.W. Wood (Carolina Nutrush)
  • Scleria pauciflora Muhl. ex Willd. var. pauciflora (Papillose Nutrush)
  • Scleria triglomerata Michaux (Tall Nutrush)
  • Scleria verticillata Muhl. ex Willd. (Whorled Nutrush)
  • Sclerochloa dura (L.) Beauv. (Hard Grass, Fairground Grass)
  • Sclerolepis uniflora (Walt.) B.S.P. (One-flowered Sclerolepis, Pink Bog-button)
  • Scopelophila ligulata (Spruce) Spruce
  • Scrophularia lanceolata Pursh (American Figwort, Lanceleaf Figwort, Early Figwort)
  • Scrophularia marilandica L. (Eastern Figwort, Late Figwort)
  • Scutellaria elliptica Muhl. ex Spreng. (Hairy Skullcap)
  • Scutellaria elliptica Muhl. ex Spreng. var. elliptica (Hairy Skullcap)
  • Scutellaria elliptica Muhl. ex Spreng. var. hirsuta (Short & Peter) Fern. (Hairy Skullcap)
  • Scutellaria galericulata L. (Hooded Skullcap, Marsh Skullcap)
  • Scutellaria incana Biehler (Hoary Skullcap, Downy Skullcap)
  • Scutellaria integrifolia L. (Hyssop Skullcap)
  • Scutellaria lateriflora L. (Mad-dog Skullcap, Blue Skullcap)
  • Scutellaria leonardii Epling (Small Skullcap, Leonard's Skullcap)
  • Scutellaria nervosa Pursh (Veined Skullcap, Veiny Skullcap)
  • Scutellaria ovata Hill (Heart-leaf Skullcap)
  • Scutellaria ovata Hill ssp. ovata (Heart-leaf Skullcap)
  • Scutellaria ovata Hill ssp. rugosa (A. Wood) Epling (Heart-leaf Skullcap)
  • Scutellaria parvula Michaux (Dwarf Scullcap)
  • Scutellaria saxatilis Riddell (Rock Skullcap)
  • Scutellaria serrata Andr. (Showy Skullcap)
  • Secale cereale L. (Rye)
  • Securigera varia (L.) Lassen (Crown Vetch)
  • Sedum acre L. (Wallpepper, Mossy Stonecrop, Gold-moss Stonecrop, Gold-moss Sedum)
  • Sedum glaucophyllum Clausen (Cliff Stonecrop)
  • Sedum pulchellum Michx. (Widow's-cross)
  • Sedum sarmentosum Bunge (Stringy Stonecrop)
  • Sedum ternatum Michx. (Wild Stonecrop, Woodland Stonecrop)
  • Selaginella apoda (L.) Spring (Meadow Spikemoss)
  • Selaginella rupestris (L.) Spring (Rock Spikemoss)
  • Sematophyllum adnatum (Michx.) E. Britton
  • Sematophyllum demissum (Wilson) Mitt.
  • Sematophyllum marylandicum (Mll. Hal.) E. Britton
  • Senecio vulgaris L. (Common Groundsel)
  • Senega ambigua (Nutt.) J.F.B. Pastore & J.R. Abbott (Loose Milkwort)
  • Senega aquilonia (Fern. & Schub.) J.F.B. Pastore & J.R. Abbott (Northern Cross-leaved Milkwort)
  • Senega cruciata (L.) J.F.B. Pastore & J.R. Abbott (Southern Cross-leaved Milkwork; Drumheads)
  • Senega curtissii (A. Gray) J.F.B. Pastore & J.R. Abbott (Curtiss' Milkwort)
  • Senega incarnata (L.) J.F.B. Pastore & J.R. Abbott (Pink Milkwort, Procession Flower)
  • Senega lutea (L.) J.F.B. Pastore & J.R. Abbott (Orange Milkwort, Yellow milkwort)
  • Senega mariana (P. Mill.) J.F.B. Pastore & J.R. Abbott (Maryland Milkwort)
  • Senega nuttallii (Torr. & A. Gray) J.F.B. Pastore & J.R. Abbott (Nuttall's Milkwort)
  • Senega officinalis Spach (Seneca Snakeroot)
  • Senega polygama (Walt.) J.F.B. Pastore & J.R. Abbott (Racemed Milkwort)
  • Senega ramosa (Ell.) J.F.B. Pastore & J.R. Abbott (Low Pine Barren Milkwort)
  • Senega sanguinea (L.) J.F.B. Pastore & J.R. Abbott (Field Milkwort, Purple Milkwort)
  • Senega verticillata (L.) J.F.B. Pastore & J.R. Abbott (Whorled Milkwort)
  • Senna hebecarpa (Fernald) Irwin & Barneby (American Senna, Northern Wild Senna)
  • Senna marilandica (L.) Link (Maryland Wild Senna, Southern Wild Senna)
  • Senna obtusifolia (L.) Irwin & Barneby (Sicklepod, Coffeeweed)
  • Senna occidentalis (L.) Link (Coffee Senna)
  • Sericocarpus asteroides (L.) B.S.P. (Toothed White-top Aster)
  • Sericocarpus caespitosus Nesom (Clumped White-top Aster)
  • Sericocarpus linifolius (L.) B.S.P. (Narrow-leaf White-top Aster)
  • Sesbania herbacea (P. Miller) McVaugh (Sesban, Coffee-weed, Indigo-weed, Peatree)
  • Sesbania punicea (Cav.) Benth. (Rattlebox Tree, Red Sesbania)
  • Sesuvium maritimum (Walter) Britton, Stearns, & Poggenberg (Small Sea-purslane, Slender Sea-purslane)
  • Setaria faberi Herrm. (Nodding Bristlegrass, Japanese Bristlegrass)
  • Setaria italica (L.) Beauv. (Foxtail-millet, Italian Bristlegrass)
  • Setaria magna Griseb. (Giant Bristlegrass, Giant Foxtail)
  • Setaria parviflora (Poir.) Kerguelen (Knotroot Bristlegrass, Knotroot Foxtail)
  • Setaria pumila (Poir.) Roemer & Schultes ssp. pumila (Yellow Bristlegrass, Yellow Foxtail)
  • Setaria verticillata (L.) Beauv. (Hooked Bristlegrass)
  • Setaria viridis (L.) Beauv. var. viridis (Green Bristlegrass, Green Foxtail)
  • Seymeria cassioides (J.F. Gmel.) Blake (Senna Seymeria)
  • Shortia galacifolia Torrey & A. Gray var. galacifolia (Shortia, Oconee Bells)
  • Sibbaldiopsis tridentata (Ait.) Rydb. (Three-toothed Cinquefoil, Mountain Cinquefoil)
  • Sicyos angulatus L. (Bur Cucumber, One-seeded Bur Cucumber, Star Cucumber)
  • Sida elliottii Torrey & Gray var. elliottii (Elliott's Sida, Elliott's Fanpetals)
  • Sida rhombifolia L. var. rhombifolia (Arrowleaf Sida)
  • Sida spinosa L. (Prickly Sida, Prickly Mallow)
  • Sideroxylon lycioides L. (Buckthorn Bumelia)
  • Silene antirrhina L. (Sleepy Catchfly)
  • Silene armeria L. (Sweet William Catchfly)
  • Silene caroliniana Walt. var. pensylvanica (Michx.) Fernald (Wild Pink, Northern Wild Pink)
  • Silene coronaria (L.) Clairville (Rose Campion, Crown Pink)
  • Silene dichotoma Ehrh. ssp. dichotoma (Forked Catchfly)
  • Silene gallica L. (Small-flowered Catchfly)
  • Silene latifolia Poir. (White Campion, Evening Lychnis)
  • Silene nivea (Nutt.) Muhl. ex Otth (Snowy Campion)
  • Silene noctiflora L. (Night-flowering Catchfly, Sticky Campion)
  • Silene ovata Pursh (Mountain Catchfly)
  • Silene rotundifolia Nutt. (Round-leaf Catchfly, Sandstone Fire Pink)
  • Silene stellata (L.) Ait. f. (Starry Campion)
  • Silene virginica L. (Fire Pink)
  • Silene vulgaris (Moench) Garcke (Bladder Campion)
  • Silphium asteriscus L. (Rosin Weed)
  • Silphium asteriscus L. var. asteriscus (Starry Rosin Weed)
  • Silphium asteriscus L. var. latifolium (Gray) Clevinger (Broad-leaved Rosin Weed)
  • Silphium asteriscus L. var. trifoliatum (L.) Clevinger (Whorled Rosin Weed)
  • Silphium compositum Michx. var. compositum (Carolina Rosin Weed)
  • Silphium compositum Michx. var. reniforme (Raf. ex Nutt.) Torr. & Gray (Kidney-leaf Rosin Weed)
  • Silphium connatum L. (Virginia Cup-plant)
  • Silphium laciniatum L. var. laciniatum (Compass-plant)
  • Silphium perfoliatum L. (Cup Plant)
  • Silphium terebinthinaceum Jacquin (Prairie Rosin Weed, Prairie Dock)
  • Silybum marianum (L.) Gaertn. (Milk Thistle, Blessed Thistle)
  • Sisymbrium altissimum Linnaeus (Tall Tumble Mustard)
  • Sisymbrium officinale (Linnaeus) Scopoli (Hedge Mustard)
  • Sisyrinchium albidum Raf. (White Blue-eyed-grass)
  • Sisyrinchium angustifolium P. Mill. (Narrow-leaved Blue-eyed-grass)
  • Sisyrinchium atlanticum Bickn. (Eastern Blue-eyed-grass, Atlantic Blue-eyed-grass)
  • Sisyrinchium capillare Bickn. (Wiry Blue-eyed-grass)
  • Sisyrinchium fuscatum Bickn. (Coastal Plain Blue-eyed-grass)
  • Sisyrinchium micranthum Cav. (Annual Blue-eyed-grass)
  • Sisyrinchium mucronatum Michx. (Needle-tip Blue-eyed-grass)
  • Sisyrinchium nashii Bicknell (Nash's Blue-eyed-grass)
  • Sitobolium punctilobulum (Michaux) Desvaux (Hay-scented Fern)
  • Sium suave Walt. (Water Parsnip)
  • Smallanthus uvedalia (L.) Mackenzie ex Small (Hairy Leafcup, Yellow-flowered Leafcup, Bear's-foot)
  • Smilax bona-nox L. var. bona-nox (Catbrier, Fringed Greenbrier)
  • Smilax bona-nox L. var. littoralis Coker ex Sorrie (Sea-side Catbrier)
  • Smilax ecirrata (Kunth) S. Wats. (Upright Carrion-flower, Upright Greenbrier)
  • Smilax glauca Walt. (White-leaf Greenbrier, Sawbrier)
  • Smilax herbacea L. (Carrion-flower, Common Carrion-flower, Smooth Carrion-flower)
  • Smilax hispida Raf. (Bristly Greenbrier, Chinaroot)
  • Smilax laurifolia L. (Laurel-leaf Greenbrier, Bamboo-vine, Blaspheme-vine)
  • Smilax pseudochina L. (Coastal Carrion-flower)
  • Smilax pulverulenta Michx. (Hairy Carrion-flower, Downy Carrion-flower)
  • Smilax rotundifolia L. (Common Greenbrier, Bullbrier, Horsebrier)
  • Smilax walteri Pursh (Red-berried Greenbrier, Coral Greenbrier)
  • Solanum carolinense L. var. carolinense (Horse-nettle, Carolina Horse-nettle)
  • Solanum dulcamara L. (Bittersweet, Climbing Nightshade)
  • Solanum emulans Raf. (Eastern Black Nightshade)
  • Solanum lycopersicum L. (Tomato)
  • Solanum nigrum L. (European Black Nightshade)
  • Solanum pseudocapsicum L. (Jerusalem Cherry)
  • Solanum rostratum Dunal (Buffalo-bur, Kansas-thistle)
  • Solanum sarrachoides Sendt. (Hairy Nightshade)
  • Solanum sisymbriifolium Lamarck (Sticky Nightshade)
  • Solenostoma appalachianum R.M.Schust. ex Bakalin
  • Solenostoma crenuliforme (Aust.) Steph.
  • Solenostoma fossombronoides (Aust.) Schust.
  • Solenostoma gracillimum (Sm.) R.M. Schust.
  • Solenostoma hyalinum (Lyell) Mitt.
  • Solenostoma infuscum (Mitt.) Hentschel
  • Solidago aestivalis Bickn. (Peat-loving Goldenrod)
  • Solidago altissima L. var. altissima (Tall Goldenrod)
  • Solidago altissima L. var. pluricephala M.C. Johnston
  • Solidago arguta Ait. (Sharp-leaved Goldenrod, Cut-leaved Goldenrod)
  • Solidago arguta Ait. var. arguta (Sharp-leaved Goldenrod; Cut-leaved Goldenrod)
  • Solidago arguta Ait. var. caroliniana Gray (Atlantic Goldenrod)
  • Solidago bicolor L. (Silverrod, White Goldenrod)
  • Solidago caesia L. var. caesia (Blue-stemmed Goldenrod, Wreath Goldenrod)
  • Solidago canadensis L. var. canadensis (Canada Goldenrod)
  • Solidago canadensis L. var. hargeri Fern. (Harger's Goldenrod)
  • Solidago curtisii Torr. & Gray (Curtis' Goldenrod)
  • Solidago erecta Pursh (Erect Goldenrod, Slender Goldenrod)
  • Solidago faucibus Wieboldt (Gorge Goldenrod)
  • Solidago fistulosa P. Mill. (Pine Barren Goldenrod)
  • Solidago flaccidifolia Small (Mountain Goldenrod, Appalachian Goldenrod)
  • Solidago flexicaulis L. (Broad-Leaved Goldenrod, Zigzag Goldenrod)
  • Solidago gigantea Ait. (Late Goldenrod)
  • Solidago harrisii Steele (Shale Barren Goldenrod)
  • Solidago hispida Muhl. ex Willd. var. hispida (Hairy Goldenrod)
  • Solidago juncea Ait. (Early Goldenrod)
  • Solidago lancifolia (Torr. & Gray) Chapman (Lance-leaf Goldenrod)
  • Solidago latissimifolia P. Mill. (Elliott's Goldenrod, Coastal Swamp Goldenrod)
  • Solidago mexicana L. (Southern Seaside Goldenrod)
  • Solidago nemoralis Ait. var. nemoralis (Gray Goldenrod)
  • Solidago odora Ait. (Sweet Goldenrod, Anise-scented Goldenrod)
  • Solidago patula Muhl. ex Willd. (Rough-leaved Goldenrod)
  • Solidago pinetorum Small (Small's Goldenrod, Pineywoods Goldenrod)
  • Solidago puberula Nutt. (Downy Goldenrod)
  • Solidago pulverulenta Nutt. (Dusty Downy Goldenrod)
  • Solidago racemosa Greene (Sticky Goldenrod)
  • Solidago randii (Porter) Britt. (Rand's Goldenrod)
  • Solidago rigida L. var. glabrata E.L. Braun (Southeastern Stiff Goldenrod)
  • Solidago rigida L. var. rigida (Stiff Goldenrod)
  • Solidago roanensis Porter (Roan Mountain Goldenrod)
  • Solidago rugosa P. Mill. (Rough-stemmed Goldenrod, Wrinkle-leaf Goldenrod)
  • Solidago rugosa P. Mill. var. aspera (Ait.) Fern. (Rough-stemmed Goldenrod, Wrinkle-leaf Goldenrod)
  • Solidago rugosa P. Mill. var. celtidifolia (Small) Fernald (Rough-stemmed Goldenrod, Wrinkle-leaf Goldenrod)
  • Solidago rugosa P. Mill. var. cronquistiana Semple (Rough-stemmed Goldenrod, Wrinkle-leaf Goldenrod)
  • Solidago rugosa P. Mill. var. rugosa (Rough-stemmed Goldenrod, Wrinkle-leaf Goldenrod)
  • Solidago rupestris Raf. (Riverbank Goldenrod, Rock Goldenrod)
  • Solidago salicina Elliott (Southern Rough-leaved Goldenrod, Round-leaf Goldenrod)
  • Solidago sempervirens L. (Northern Seaside Goldenrod)
  • Solidago speciosa Nutt. (Showy Goldenrod)
  • Solidago sphacelata Raf. (Limestone Goldenrod, False Goldenrod)
  • Solidago squarrosa Nutt. (Stout Goldenrod)
  • Solidago stricta Ait. (Southern Bog Goldenrod, Virginia Goldenrod)
  • Solidago tarda Mackenzie (Sandhill Goldenrod)
  • Solidago tortifolia Ell. (Twisted-leaf Goldenrod, Leafy Pineywoods Goldenrod)
  • Solidago uliginosa Nutt. var. uliginosa (Bog Goldenrod)
  • Solidago ulmifolia Muhl. ex Willd. (Elm-leaf Goldenrod)
  • Soliva sessilis Ruiz & Pavon (Field Burweed, Lawn Burweed)
  • Sonchus arvensis L. var. glabrescens Guenth., Grab. & Wimmer (Field Sow Thistle)
  • Sonchus asper (L.) Hill (Spiny-leaf Sow Thistle)
  • Sonchus oleraceus L. (Common Sow Thistle)
  • Sophronanthe pilosa (Michx.) Small (Shaggy Hedge-hyssop)
  • Sorbus americana Marsh. (American Mountain-ash)
  • Sorghastrum elliottii (C. Mohr) Nash (Slender Indian Grass)
  • Sorghastrum nutans (L.) Nash (Indian Grass, Yellow Indian Grass)
  • Sorghum halepense (L.) Pers. (Johnson Grass)
  • Sparganium acaule (Beeby ex Macoun) Rydberg (Narrow-leaf Bur-reed)
  • Sparganium americanum Nutt. (American Bur-reed)
  • Sparganium eurycarpum Engelm. ex Gray (Giant Bur-reed)
  • Spartina alterniflora Loisel. (Saltmarsh Cordgrass, Smooth Cordgrass)
  • Spartina cynosuroides (L.) Roth (Big Cordgrass, Giant Cordgrass)
  • Spartina patens (Ait.) Muhl. (Saltmeadow Cordgrass, Saltmeadow Hay)
  • Spartina pectinata Link (Freshwater Cordgrass, Prairie Cordgrass)
  • Spergula arvensis L. (Corn Spurry)
  • Spergula pentandra L. (Wing-stem Spurry)
  • Spergularia marina (L.) Besser (Salt-marsh Sand Spurry, Lesser Sand Spurry)
  • Spergularia rubra (L.) J. & K. Presl (Purple Sand-spurrey)
  • Spermacoce glabra Michx. (Smooth False Buttonweed)
  • Spermolepis divaricata (Walt.) Raf. (Rough-fruit Scale-seed, Rough-fruit Spermolepis)
  • Spermolepis echinata (Nutt. ex DC.) Heller (Bristle-fruit Spermolepis, Hooked Spermolepis)
  • Sphaerocarpos michelii Bellardi
  • Sphaerocarpos texanus Austin
  • Sphaerosporoceros adscendens (Lehm. & Lindenb.) Hssel
  • Sphagnum affine Renauld & Cardot
  • Sphagnum angustifolium (Warnst.) C.E.O. Jensen
  • Sphagnum atlanticum R.E. Andrus
  • Sphagnum bartlettianum Warnstorf
  • Sphagnum capillifolium (Ehrh.) Hedw.
  • Sphagnum carolinianum R. E. Andrus
  • Sphagnum compactum Lam. & DC.
  • Sphagnum contortum Schultz
  • Sphagnum cuspidatum Hoffm.
  • Sphagnum cyclophyllum Sullivant
  • Sphagnum fallax (H. Klinggr.) H. Klinggr.
  • Sphagnum fimbriatum Wilson & Hook. ssp. fimbriatum
  • Sphagnum fitzgeraldii Lesq. & James
  • Sphagnum flavicomans (Cardot) Warnst.
  • Sphagnum flexuosum Dozy & Molkenboer
  • Sphagnum fuscum (Schimp.) H. Klinggr.
  • Sphagnum girgensohnii Russow
  • Sphagnum henryense Warnstorf
  • Sphagnum inundatum Russow
  • Sphagnum isoviitae Flatberg
  • Sphagnum lescurii Sullivant
  • Sphagnum macrophyllum Bridel
  • Sphagnum magellanicum Bridel
  • Sphagnum molle Sull.
  • Sphagnum palustre Linnaeus
  • Sphagnum papillosum Lindb.
  • Sphagnum perichaetiale Hampe
  • Sphagnum playtphyllum (Lindb.) Warnst.
  • Sphagnum portoricense Hampe
  • Sphagnum pulchrum (Lindb.) Warnst.
  • Sphagnum quinquefarium (Lindb.) Warnst.
  • Sphagnum recurvum Palisot de Beauvois
  • Sphagnum rubellum Wilson
  • Sphagnum russowii Warnst.
  • Sphagnum strictum Sullivant
  • Sphagnum subsecundum Nees
  • Sphagnum subtile (Russow) Warnst.
  • Sphagnum tenerum Sullivant
  • Sphagnum torreyanum Sullivant
  • Sphagnum trinitense Mll. Hal.
  • Sphagnum viride Flatberg
  • Sphenolobopsis pearsonii (Spruce) R.M. Schust.
  • Sphenolobus minutus (Schreb.) Berggr.
  • Sphenopholis filiformis (Chapman) Scribn. (Long-leaf Wedgegrass)
  • Sphenopholis nitida (Biehler) Scribn. (Shiny Wedgegrass)
  • Sphenopholis obtusata (Michx.) Scribn. var. major (Torr.) K.S. Erdman (Slender Wedgegrass)
  • Sphenopholis obtusata (Michx.) Scribn. var. obtusata (Prairie Wedgegrass)
  • Sphenopholis pensylvanica (L.) A.S. Hitchc. (Swamp Wedgegrass)
  • Sphenopholis pallens (Biehler) Scribn.
  • Spinulum annotinum (L.) A. Haines (Stiff Clubmoss, Bristly Clubmoss)
  • Spiraea alba Du Roi var. alba (Narrowleaf Meadowsweet)
  • Spiraea alba Du Roi var. latifolia (Ait.) Dippel (Broadleaf Meadowsweet)
  • Spiraea corymbosa Raf. (Dwarf Spiraea)
  • Spiraea japonica L. f. (Japanese Spiraea)
  • Spiraea prunifolia Sieb. & Zucc. (Bridal-wreath Spiraea)
  • Spiraea salicifolia L. (Willow-leaf Meadowsweet)
  • Spiraea tomentosa L. (Steeplebush, Hardhack)
  • Spiraea virginiana Britt. (Virginia Spiraea)
  • Spiraea billiardii Herinq. (Billard's Spiraea)
  • Spiraea vanhouttei (Briot) Carr. (Van Houtte Spiraea)
  • Spiranthes arcisepala M.C. Pace
  • Spiranthes bightensis M.C. Pace
  • Spiranthes cernua (L.) L.C. Rich. (Nodding Ladies'-tresses)
  • Spiranthes eatonii Ames ex P.M. Brown (Eaton's Ladies'-tresses)
  • Spiranthes lacera (Raf.) Raf. var. gracilis (Bigelow) Luer (Southern Slender Ladies'-tresses)
  • Spiranthes lacera (Raf.) Raf. var. lacera (Northern Slender Ladies'-tresses)
  • Spiranthes laciniata (Small) Ames (Lace-lip Ladies'-tresses)
  • Spiranthes lucida (H.H.Eat.) Ames (Shining Ladies'-tresses)
  • Spiranthes magnicamporum Sheviak (Great Plains Ladies'-tresses)
  • Spiranthes ochroleuca (Rydb.) Rydb. (Yellow Nodding Ladies'-tresses)
  • Spiranthes odorata (Nutt.) Lindl. (Fragrant Ladies'-tresses, Marsh Ladies'-tresses)
  • Spiranthes ovalis Lindl. var. erostellata Catling (Oval Ladies'-tresses, October Ladies'-tresses)
  • Spiranthes praecox (Walt.) S.Wats. (Grass-leaved Ladies'-tresses, Giant Ladies'-tresses)
  • Spiranthes sylvatica P.M. Brown (Woodland Ladies'-tresses, Pale Green Ladies'-tresses)
  • Spiranthes tuberosa Raf. (Little Ladies'-tresses)
  • Spiranthes vernalis Engelm. & Gray (Twisted Ladies'-tresses, Spring Ladies'-tresses)
  • Spirobassia hirsuta (L.) Frietag & G. Kadereit (Hairy Smother-weed, Hairy Sea-blite)
  • Spirodela polyrrhiza (L.) Schleid. (Greater Duckweed, Duckmeal)
  • Sporobolus clandestinus (Biehler) A.S. Hitchc. (Rough Dropseed)
  • Sporobolus compositus (Poir.) Merr. var. compositus (Tall Dropseed, Longleaf Dropseed)
  • Sporobolus heterolepis (Gray) Gray (Prairie Dropseed, Northern Dropseed)
  • Sporobolus indicus (L.) R. Br. (Smut Grass)
  • Sporobolus junceus (Beauv.) Kunth (Purple Dropseed, Pineywoods Dropseed)
  • Sporobolus neglectus Nash (Small Dropseed)
  • Sporobolus ozarkanus Fernald (Ozark Dropseed)
  • Sporobolus vaginiflorus (Torr. ex Gray) Wood (Poverty Dropseed, Sheathed Dropseed)
  • Stachys annua (L.) L. (Annual Hedge-nettle)
  • Stachys appalachiana D.B. Poindexter & J.B. Nelson (Appalachian Hedge-nettle)
  • Stachys arenicola Britt. (Hairy Hedge-nettle)
  • Stachys aspera Michx. (Rough Hedge-nettle)
  • Stachys byzantina K. Koch ex Scheele (Woolly Hedge-nettle, Lamb's-ear)
  • Stachys cordata Riddell (Heart-leaf Hedge-nettle)
  • Stachys eplingii J. Nelson (Epling's Hedge-nettle)
  • Stachys floridana Shuttlw. ex Benth. (Florida Hedge-nettle, Florida Betony)
  • Stachys germanica L. (German Hedge-nettle, Downy Woundwort)
  • Stachys hispida Pursh (Hispid Hedge-nettle, Bristly Hedge-nettle)
  • Stachys hyssopifolia Michx. (Hyssop-leaf Hedge-nettle, Hyssop Hedge-nettle)
  • Stachys latidens Small ex Britt. (Broad-tooth Hedge-nettle)
  • Stachys matthewsii G.P. Fleming, J.B. Nelson, & J.F. Townsend (Yadkin Hedge-nettle)
  • Stachys palustris L. (Woundwort, Marsh Hedge-nettle, Marsh Woundwort)
  • Stachys subcordata Rydb. (Blue Ridge Hedge-nettle)
  • Stachys tenuifolia Willd. (Smooth Hedge-nettle)
  • Staphylea trifolia L. (Bladdernut)
  • Steinchisma hians (Ell.) Nash (Gaping Panic Grass)
  • Steironema ciliatum (L.) Baudo (Fringed Loosestrife)
  • Steironema hybridum (Michaux) Raf. ex B.D. Jackson (Lowland Loosestrife)
  • Steironema lanceolatum (Walt.) Gray (Lanceleaf Loosestrife)
  • Steironema quadriflorum (Sims) A.S. Hitchcock (Prairie Loosestrife, Four-flowered Loosestrife)
  • Steironema radicans (Hooker) A. Gray (Trailing Loosestrife)
  • Steironema tonsum (Alph. Wood) E.P. Bicknell ex Britton (Southern Loosestrife, Appalachian Loosestrife)
  • Stellaria alsine Grimm (Bog Chickweed, Bog Stitchwort)
  • Stellaria aquatica (L.) Scopoli (Giant Chickweed, Water Chickweed)
  • Stellaria corei Shinners (Tennessee Starwort)
  • Stellaria graminea L. (Common Stitchwort, Lesser Stitchwort)
  • Stellaria longifolia Muhl. (Long-leaf Stitchwort)
  • Stellaria media (L.) Vill. (Common Chickweed)
  • Stellaria pallida (Dumort.) Crepin (Lesser Chickweed)
  • Stellaria pubera Michx. (Star Chickweed, Common Starwort, Giant Chickweed, Great Chickweed)
  • Stenanthium densum (Desr.) Zomlefer & Judd (Dense-flowered Camas)
  • Stenanthium gramineum (Ker-Gawl.) Morong var. gramineum (Common Featherbells)
  • Stenanthium gramineum (Ker-Gawl.) Morong var. robustum (S. Wats.) Fern. (Giant Featherbells)
  • Stenanthium leimanthoides (Gray) Zomlefer & Judd. (Pinebarrens Death-camas)
  • Stenotaphrum secundatum (Walt.) Kuntze (St. Augustine Grass, Carpet Grass)
  • Stewartia malacodendron L. (Silky Camellia, Virginia Stewartia)
  • Stewartia ovata (Cav.) Weatherby (Mountain Camellia, Mountain Stewartia)
  • Stillingia sylvatica Garden ex L. (Queen's-delight)
  • Stipulicida setacea Michx. (Pineland Scalypink)
  • Straminergon stramineum (Dicks. ex Brid.) Hedens
  • Streptopus amplexifolius (L.) DC. (White Mandarin, Pagoda-bells)
  • Streptopus lanceolatus (Ait.) Reveal (Eastern Rose Mandarin, Eastern Twisted-stalk)
  • Strophostyles helvola (L.) Ell. (Beach Bean, Trailing Wild Bean, Amberique Bean)
  • Strophostyles leiosperma (Torr. & Gray) Piper (Small-flowered Sand Bean)
  • Strophostyles umbellata (Muhl. ex Willd.) Britt. (Pink Wild Bean, Perennial Wild Bean)
  • Stuckenia pectinata (L.) Borner (Sago Pondweed)
  • Stylisma humistrata (Walt.) Chapman (Southern Dawnflower)
  • Stylophorum diphyllum (Michaux) Nuttall (Celandine Poppy, Wood Poppy)
  • Stylosanthes biflora (L.) B.S.P. (Pencilflower)
  • Styphnolobium japonicum (L.) Schott (Pagoda Tree)
  • Styrax americanus Lamarck var. americanus (American Snowbell)
  • Styrax grandifolius Aiton (Bigleaf Snowbell)
  • Styrax japonicus Sieb. & Zucc. (Japanese Snowbell)
  • Suaeda linearis (Ell.) Moq. (Tall Sea-blite, Southern Sea-blite)
  • Suaeda maritima (L.) Dumort (Common Sea-blite, White Sea-blite)
  • Sullivantia sullivantii (Torr. & Gray) Britt. (Sullivantia, Sullivant's Coolwort)
  • Swida alternifolia (L.f.) Small (Alternate-leaf Dogwood, Pagoda Cornel, Pagoda Dogwood)
  • Swida amomum (P. Miller) Small (Silky Dogwood)
  • Swida drummondii (C.A. Meyer) Sojk (Midwestern Roughleaf Dogwood)
  • Swida foemina (P. Miller) Rydberg (Stiff Dogwood, Swamp Dogwood)
  • Swida obliqua (Raf.) Moldenke (Silky Dogwood)
  • Swida racemosa (Lamarck) Moldenke (Gray Dogwood)
  • Swida rugosa (Lamarck) Rydberg (Roundleaf Dogwood)
  • Swida sericea (L.) Holub (Red-osier Dogwood)
  • Symphoricarpos albus (L.) Blake (Snowberry)
  • Symphoricarpos albus (L.) Blake var. albus (Common Snowberry)
  • Symphoricarpos albus (L.) Blake var. laevigatus (Fern.) Blake (Smooth Snowberry)
  • Symphoricarpos orbiculatus Moench (Coralberry)
  • Symphyotrichum concinnum (Willd.) Mohlenbr. (Narrow-leaved Smooth Aster)
  • Symphyotrichum concolor (L.) Nesom (Eastern Silvery Aster)
  • Symphyotrichum cordifolium (L.) Nesom (Heart-leaved Aster, Blue Wood Aster)
  • Symphyotrichum divaricatum (Nutt.) Nesom (Southern Annual Salt-marsh Aster)
  • Symphyotrichum dumosum (L.) Nesom var. dumosum (Bushy Aster)
  • Symphyotrichum dumosum (L.) Nesom var. strictior (Torr. & Gray) Nesom (Bushy Aster)
  • Symphyotrichum elliottii (Torr. & Gray) Nesom (Elliott's Aster)
  • Symphyotrichum ericoides (L.) Nesom var. ericoides (White Heath Aster)
  • Symphyotrichum grandiflorum (L.) Nesom (Large-flowered Aster)
  • Symphyotrichum laeve (L.) A. & D. Love (Smooth Blue Aster, Smooth Aster)
  • Symphyotrichum lanceolatum (Willd.) Nesom (Panicled Aster, Eastern Lined Aster)
  • Symphyotrichum lateriflorum (L.) A.& D. Love (Calico Aster, Starved Aster)
  • Symphyotrichum lowrieanum (Porter) Nesom (Lowrie's Aster, Lowrie's Blue Wood Aster)
  • Symphyotrichum novae-angliae (L.) Nesom (New England Aster)
  • Symphyotrichum novi-belgii (L.) Nesom (New York Aster)
  • Symphyotrichum oblongifolium (Nutt.) Nesom (Aromatic Aster)
  • Symphyotrichum ontarionis (Wiegand) Nesom var. ontarionis (Bottomland Aster, Lake Ontario Aster)
  • Symphyotrichum patens (Ait.) Nesom var. patens (Late Purple Aster)
  • Symphyotrichum phlogifolium (Muhl. ex Willd.) Nesom (Thin-leaf Late Purple Aster)
  • Symphyotrichum pilosum (Willd.) Nesom (Frost Aster)
  • Symphyotrichum pilosum (Willd.) Nesom var. pilosum (Frost Aster, White Old-field Aster, Awl Aster)
  • Symphyotrichum pilosum (Willd.) Nesom var. pringlei (Gray) Nesom (Frost Aster; Pringle's Aster)
  • Symphyotrichum praealtum (Poir.) Nesom var. angustior (Wieg.) Nesom (Willow-leaf Aster)
  • Symphyotrichum pratense (Raf.) Nesom (Western Silvery Aster, Barrens Silky Aster)
  • Symphyotrichum prenanthoides (Muhl. ex Willd.) Nesom (Crooked-stem Aster)
  • Symphyotrichum puniceum (L.) A.& D. Love var. puniceum (Purple-stem Aster)
  • Symphyotrichum racemosum (Ell.) Nesom var. racemosum (Small White Aster)
  • Symphyotrichum racemosum (Ell.) Nesom var. subdumosum (Wieg.) Nesom (Oldfield Small White Aster)
  • Symphyotrichum schistosum (E.S. Steele) Nesom (Millboro Aster)
  • Symphyotrichum shortii (Lindl.) Nesom (Short's Aster)
  • Symphyotrichum subulatum (Michx.) Nesom (Annual Salt-marsh Aster)
  • Symphyotrichum tenuifolium (L.) Nesom (Perennial Salt-marsh Aster)
  • Symphyotrichum undulatum (L.) Nesom (Wavy-leaved Aster)
  • Symphyotrichum urophyllum (Lindl.) Nesom (Arrow-leaved Aster)
  • Symphytum officinale L. (Common Comfrey)
  • Symplocarpus foetidus (L.) Salisbury ex W.P. C. Barton (Skunk Cabbage)
  • Symplocos tinctoria (L.) L'Her. (Common Sweetleaf, Horse-sugar)
  • Synandra hispidula (Michx.) Baill. (Guyandotte Beauty)
  • Syntrichia amphidiacea (Mll. Hal.) R.H. Zander
  • Syntrichia fragilis (Taylor) Ochyra
  • Syntrichia pagorum (Milde) J.J. Amann
  • Syntrichia papillosa (Wilson) Jur.
  • Syringa vulgaris L. (Common Lilac)
  • Syrrhopodon incompletus Schwgr.
  • Syrrhopodon texanus Sull.
  • Syzygiella autumnalis (DC.) K. Feldberg, Vna, Hentschel & J. Heinrichs
  • Syzygiella nipponica (S. Hatt.) K. Feldberg, Vna, Hentschel & J. Heinrich
  • Taenidia integerrima (L.) Drude (Yellow Pimpernel)
  • Taenidia montana (Mackenzie) Cronq. (Mountain Pimpernel)
  • Tagetes erecta L. (Common Marigold, African Marigold)
  • Tagetes minuta L. (Mexican Marigold, Southern Cone Marigold, Muster John Henry)
  • Tagetes patula L. (French Marigold)
  • Tamala palustris Rafinesque (Red Bay, Swamp Bay, Swamp Red Bay)
  • Tamarix gallica L. (French Tamarisk)
  • Tamarix ramosissima Ledeb. (Saltcedar)
  • Tanacetum parthenium (L.) Schultz Bip. (Feverfew)
  • Tanacetum vulgare L. (Common Tansy)
  • Taraxacum erythrospermum Andrzejowski ex Besser (Red-seeded Dandelion)
  • Taraxacum officinale G.H. Weber ex Wiggers (Common Dandelion)
  • Tarenaya hassleriana (Chodat) H.H. Iltis (Cleome, Spider Flower, Pink Queen)
  • Taxiphyllum deplanatum (Bruch & Schimp. ex Sull.) M. Fleisch.
  • Taxiphyllum taxirameum (Mitt.) M. Fleisch.
  • Taxodium ascendens Brongniart (Pondcypress)
  • Taxodium distichum (L.) Richard (Baldcypress)
  • Taxus baccata L. (English Yew)
  • Taxus canadensis Marshall (Canada Yew, American Yew)
  • Teesdalia nudicaulis (L.) W.T. Ait. (Common Shepherd's Cress, Bank Cress)
  • Telaranea longifolia (M. Howe) J. J. Engel & G. L. Merr.
  • Tephrosia purpurea (L.) Pers. (Fishpoison)
  • Tephrosia spicata (Walt.) Torr. & Gray (Spiked Hoary Pea, Red Hoary Pea)
  • Tephrosia virginiana (L.) Pers. (Virginia Goat's-rue)
  • Tetradium daniellii (Benn.) T.G. Hartley (Bee-bee Tree)
  • Tetragonotheca helianthoides L. (Squarehead, Pineland Nerveray)
  • Tetraphis pellucida Hedwig var. pellucida
  • Teucrium botrys L. (Cut-leaf Germander)
  • Teucrium canadense L. var. canadense (Canada Germander, American Germander)
  • Thalictrum amphibolum Greene (Skunk Meadow-rue)
  • Thalictrum clavatum DC. (Lady-rue, Mountain Meadow-rue)
  • Thalictrum coriaceum (Britt.) Small (Appalachian Meadow-rue, Leatherleaf Meadow-rue, Maid of the Mist)
  • Thalictrum dasycarpum Fisher & Lall. (Purple Meadow-rue)
  • Thalictrum dioicum L. (Early Meadow-rue)
  • Thalictrum macrostylum Small & Heller (Small-leaved Meadow-rue)
  • Thalictrum pubescens Pursh (Common Tall Meadow-rue)
  • Thalictrum thalictroides (L.) Eames & Boivin (Rue-anemone)
  • Thamnobryum alleghaniense (Mll. Hal.) Nieuwl.
  • Thaspium barbinode (Michx.) Nutt. (Hairy-jointed Meadow Parsnip)
  • Thaspium trifoliatum (L.) Gray (Meadow Parsnip, Purple Meadow Parsnip)
  • Thelia asprella (Schimp.) Sull.
  • Thelia hirtella (Hedw.) Sull.
  • Thelia lescurii Sullivant
  • Thelypteris palustris Schott var. pubescens (Lawson) Fern. (Marsh Fern)
  • Themeda arguens (L.) Hack. (Christmas Grass)
  • Thermopsis mollis (Michx.) M.A. Curtis ex Gray (Appalachian Golden-banner)
  • Thermopsis villosa (Walt.) Fern. & Schub. (Aaron's-rod, Blue Ridge Golden-banner)
  • Thlaspi arvense Linnaeus (Field Pennycress)
  • Thuidium alleniorum Austin
  • Thuidium delicatulum (Hedw.) Schimp. (Delicate Fern Moss)
  • Thuidium recognitum (Hedw.) Lindb. (Kilt Fern Moss)
  • Thuja occidentalis L. (American Arborvitae, Northern Whitecedar, Flat Cedar)
  • Thymus pulegioides L. (Broad-leaved Thyme, Lemon Thyme)
  • Thyrsanthella difformis (Walter) Pichon (Climbing Dogbane)
  • Tiarella cordifolia L. (Heartleaf Foamflower)
  • Tiarella stolonifera Nesom (Creeping Foamflower)
  • Tilia americana L. (Basswood)
  • Tilia americana L. var. americana (American Basswood)
  • Tilia americana L. var. heterophylla (Vent.) Loud. (White Basswood)
  • Tillandsia usneoides (L.) L. (Spanish-moss)
  • Timmia megapolitana Hedw. ssp. megapolitana
  • Tipularia discolor (Pursh) Nutt (Cranefly Orchid)
  • Torenia crustacea (L.) Chamisso & Schlechtendal (Malaysian False-pimpernel)
  • Torilis arvensis (Huds.) Link ssp. recta Jury (Spreading Hedge Parsley)
  • Torilis japonica (Houtt.) DC. (Japanese Hedge Parsley)
  • Torrentaria riparioides (Hedw.) Ochyra
  • Torreyochloa pallida (Torr.) Church var. pallida (Pale Mannagrass)
  • Tortella humilis (Hedw.) Jenn.
  • Tortella tortuosa (Hedw.) Limpr. var. tortuosa
  • Tortula acaulon (With.) R.H. Zander
  • Tortula muralis Hedwig
  • Tortula obtusifolia (Schwgr.) Mathieu
  • Tortula porteri (James) Broth.
  • Tortula truncata (Hedw.) Mitt.
  • Toxicodendron pubescens P.Miller (Poison Oak)
  • Toxicodendron radicans (L.) Kuntze var. negundo (Greene) Reveal (Midwestern Poison Ivy)
  • Toxicodendron radicans (L.) Kuntze var. pubens (Engelm. ex S. Wats.) Reveal (Poison Ivy)
  • Toxicodendron radicans (L.) Kuntze var. radicans (Poison Ivy, Eastern Poison Ivy)
  • Toxicodendron rydbergii (Small ex Rydberg) Greene (Western Poison Ivy)
  • Toxicodendron vernix (L.) Kuntze (Poison Sumac)
  • Tradescantia ohiensis Rafinesque (Ohio Spiderwort, Smooth Spiderwort)
  • Tradescantia subaspera Ker-Gawler (Zigzag Spiderwort, Wide-leaved Spiderwort)
  • Tradescantia virginiana L. (Virginia Spiderwort)
  • Tragia betonicifolia Nuttall (Betony-leaf Noseburn)
  • Tragia urens L. (Wavy-leaf Noseburn)
  • Tragia urticifolia Michx. (Nettle-leaf Noseburn)
  • Tragopogon dubius Scop. (Western Salsify, Yellow Salsify, Yellow Goat's-beard)
  • Tragopogon porrifolius L. (Purple Salsify, Vegetable-oyster)
  • Tragopogon pratensis L. (Meadow Salsify, Showy Goat's-beard)
  • Tragus berteronianus J.A. Schultes (Spiked Burgrass)
  • Tragus racemosus (L.) All. (Stalked Burgrass, Texas Burgrass)
  • Trapa bispinosa Roxb. var. iinumae Nakano (Two-horned Water-Chestnut, Two-horned Trapa)
  • Trapa natans L. (Chinese Water-chestnut, European Water-chestnut, Water-caltrop)
  • Trautvetteria caroliniensis (Walt.) Vail (Tassel-rue)
  • Trematodon ambiguus (Hedwig) Hornschuch
  • Trematodon longicollis Michaux
  • Triadenum fraseri (Spach) Gleason (Fraser's Marsh St. John's-wort)
  • Triadenum tubulosum (Walt.) Gleason (Lesser Marsh St. John's-wort)
  • Triadenum virginicum (L.) Raf. (Virginia Marsh St. John's-wort, Common Marsh St. John's-wort)
  • Triadenum walteri (J. G.Gmel.) Gleason (Greater Marsh St. John's-wort)
  • Triadica sebifera (L.) Small (Chinese Tallow Tree)
  • Triantha glutinosa (Michx.) Baker (Sticky False Asphodel, Sticky Bog Asphodel)
  • Triantha racemosa (Walt.) Small (Coastal False Asphodel, Coastal Bog Asphodel)
  • Tribulus terrestris L. (Puncture-vine)
  • Trichocolea tomentella (Ehrh.) Dumort.
  • Trichophorum planifolium (Sprengel) Palla (Bashful Bulrush)
  • Trichostema coeruleum (Michx.) K.S.McClell. & Weakley (False Pennyroyal)
  • Trichostema dichotomum L. (Common Blue Curls, Forked Blue Curls)
  • Trichostema setaceum Houtt. (Narrow-leaf Blue Curls)
  • Trichostomum tenuirostre (Hook. & Taylor) Lindb. var. tenuirostre
  • Tridens chapmanii (Small) Chase (Chapman's Purpletop, Chapman's Redtop)
  • Tridens flavus (L.) A.S. Hitchc. (Purpletop, Tall Redtop)
  • Tridens strictus (Nutt.) Nash (Long-spike Tridens, Long-spike Fluffgrass)
  • Trientalis borealis Raf. (Northern Starflower)
  • Trifolium arvense L. (Rabbit-foot Clover)
  • Trifolium aureum Pollich (Golden Clover, Large Hop Clover)
  • Trifolium calcaricum Collins & Wieboldt (Running Glade Clover)
  • Trifolium campestre Schreb. (Low Hop Clover)
  • Trifolium dubium Sibthorp (Lesser Hop Clover, Least Hop Clover)
  • Trifolium hirtum All. (Rose Clover)
  • Trifolium hybridum L. (Alsike Clover)
  • Trifolium incarnatum L. (Crimson Clover)
  • Trifolium pratense L. (Red Clover)
  • Trifolium reflexum L. (Buffalo Clover)
  • Trifolium repens L. (White Clover, Dutch Clover)
  • Trifolium vesiculosum Savi (Arrowleaf Clover)
  • Trifolium virginicum Small (Kates Mountain Clover)
  • Triglochin striata Ruiz & Pavon (Southern Arrowgrass, Three-ribbed Arrowgrass)
  • Trillidium undulatum Floden & E.E. Schilling (Painted Trillium, Striped Wake-robin)
  • Trillium cernuum L. (Nodding Trillium)
  • Trillium cuneatum Raf. (Large Toadshade, Purple Toadshade)
  • Trillium erectum L. (Red Trillium, Wake-robin, Stinking Benjamin)
  • Trillium flexipes Raf. (Drooping Trillium, Nodding Wake-robin)
  • Trillium grandiflorum (Michx.) Salisb. (Large-flowered Trillium, Great White Trillium)
  • Trillium luteum (Muhl.) Harbison (Yellow Trillium, Yellow Toadshade, Lemon-scented Trillium)
  • Trillium nivale Riddell (Snow Trillium, Dwarf White Trillium)
  • Trillium pusillum Michx. var. virginianum Fern. (Virginia Least Trillium, Virginia Dwarf Trillium)
  • Trillium sessile L. (Sessile Trillium, Toad Trillium, Toadshade)
  • Trillium sulcatum Patrick (Southern Red Trillium, Barksdale Trillium)
  • Triodanis biflora (Ruiz & Pavon) Greene (Small Venus' Looking-glass)
  • Triodanis perfoliata (L.) Nieuwl. (Venus' Looking-glass, Common Venus' Looking-glass)
  • Triosteum angustifolium L. (Lesser Horse-gentian, Yellow Horse-gentian)
  • Triosteum aurantiacum Bickn. var. aurantiacum (Orange-fruited Horse-gentian, Coffee Tinker's-weed)
  • Triosteum perfoliatum L. (Feverwort, Late Horse-gentian)
  • Triphora trianthophora (Sw.) Rydb. ssp. trianthophora (Three Birds Orchid, Nodding Pogonia)
  • Tripidium ravennae (L.) Scholz (Ravenna-grass)
  • Triplasis purpurea (Walt.) Chapman var. purpurea (Purple Sandgrass)
  • Tripsacum dactyloides (L.) L. var. dactyloides (Eastern Gamagrass)
  • Tristagma uniflorum (Graham) Traub (Spring Star, Spring Starflower)
  • Triticum aestivum L. (Wheat)
  • Tritomaria exsecta (Schmidel) Schiffn. ex Loeske
  • Tritomaria exsectiformis (Breidl.) Schiffn. ex Loeske
  • Tsuga canadensis (L.) Carriere (Eastern Hemlock, Canada Hemlock)
  • Tsuga caroliniana Engelm. (Carolina Hemlock)
  • Tuerckheimia svihlae (E.B. Bartram) R.H. Zander
  • Turritis glabra L. (Tower Mustard)
  • Tussilago farfara L. (Coltsfoot)
  • Typha angustifolia L. (Narrowleaf Cattail)
  • Typha domingensis Pers. (Southern Cattail)
  • Typha latifolia L. (Common Cattail, Broadleaf Cattail)
  • Typha glauca Godron (Hybrid Cattail)
  • Ulex europaeus L. (Gorse)
  • Ulmus alata Michx. (Winged Elm)
  • Ulmus americana L. (American Elm)
  • Ulmus parvifolia Jacq. (Chinese Elm, Lacebark Elm)
  • Ulmus procera Salisb. (English Elm)
  • Ulmus pumila L. (Siberian Elm)
  • Ulmus rubra Muhl. (Slippery Elm, Red Elm)
  • Ulota coarctata (P. Beauv.) Hammar (Puckered Tuft Moss)
  • Ulota crispa (Hedw.) Brid.
  • Ulota hutchinsiae (Sm.) Hammar var. hutchinsiae (Rock Tuft Moss)
  • Ulota hutchinsiae var. rufescens (E. Britton) Dixon
  • Uniola paniculata L. (Sea Oats)
  • Urochloa adspersa (Trin.) R. Webster (Dominican Signal-grass)
  • Urochloa platyphylla (Munro ex Wright) R. Webster (Broadleaf Signal-grass)
  • Urochloa ramosa (L.) Nguyen (Browntop Millet, Dixie Signal-grass)
  • Urochloa texana (Buckl.) R. Webster (Texas Millet, Texas Signal-grass)
  • Urochloa villosa (Lam.) Nguyen (Hairy Signal-grass)
  • Urtica dioica L. (European Stinging Nettle, Great Nettle)
  • Urtica dioica L. + Urtica gracilis Ait. ssp. gracilis (Stinging Nettle)
  • Urtica gracilis Ait. ssp. gracilis (American Stinging Nettle)
  • Urtica urens L. (Burning Nettle, Dog Nettle, Small Nettle)
  • Utricularia biflora Lam. (Longspur Creeping Bladderwort)
  • Utricularia geminiscapa Benj. (Two-flowered Bladderwort, Hidden-fruited Bladderwort)
  • Utricularia gibba L. (Humped Bladderwort, Shortspur Creeping Bladderwort)
  • Utricularia inflata Walt. (Swollen Bladderwort, Inflated Bladderwort)
  • Utricularia juncea Vahl (Southern Bladderwort)
  • Utricularia macrorhiza Le Conte (Common Bladderwort, Greater Bladderwort)
  • Utricularia purpurea Walt. (Purple Bladderwort)
  • Utricularia radiata Small (Floating Bladderwort, Small Swollen Bladderwort)
  • Utricularia striata Le Conte ex Torrey (Fibrous Bladderwort)
  • Utricularia subulata L. (Slender Bladderwort, Zigzag Bladderwort)
  • Uvularia grandiflora Sm. (Large-flowered Bellwort)
  • Uvularia perfoliata L. (Perfoliate Bellwort)
  • Uvularia puberula Michx. (Mountain Bellwort, Common Bellwort)
  • Uvularia sessilifolia L. (Sessile Bellwort, Wild-oats)
  • Vaccaria hispanica (P. Mill.) Rausch. (Cow-cockle, Cow-herb)
  • Vaccinium altomontanum W.W. Ashe (Blue Ridge Blueberry)
  • Vaccinium angustifolium Ait. (Northern Lowbush Blueberry)
  • Vaccinium arboreum Marsh. (Farkleberry, Sparkleberry)
  • Vaccinium caesariense Mackenzie (New Jersey Blueberry, New Jersey Highbush Blueberry)
  • Vaccinium corymbosum L. (Highbush Blueberry, Northern Highbush Blueberry)
  • Vaccinium crassifolium Andrews ssp. crassifolium (Creeping Blueberry)
  • Vaccinium elliottii Chapman (Elliott's Blueberry, Mayberry)
  • Vaccinium erythrocarpum Michx. (Southern Mountain Cranberry, Highbush Cranberry)
  • Vaccinium formosum Andr. (Southern Highbush Blueberry, Swamp Highbush Blueberry)
  • Vaccinium fuscatum Ait. (Hairy Highbush Blueberry, Black Highbush Blueberry)
  • Vaccinium macrocarpon Ait. (Cranberry, Large Cranberry)
  • Vaccinium myrtilloides Michx. (Velvetleaf Blueberry, Canada Blueberry)
  • Vaccinium pallidum Ait. (Early Lowbush Blueberry, Hillside Blueberry)
  • Vaccinium simulatum Small (Mountain Highbush Blueberry)
  • Vaccinium stamineum L. (Deerberry)
  • Vaccinium tenellum Ait. (Small Black Blueberry)
  • Vaccinium margarettiae Ashe (pro sp.)
  • Vaccinium marianum S. Wats. (pro sp.)
  • Vachellia constricta (Benth.) Seigler & Ebinger (Whitethorn Acacia)
  • Valeriana pauciflora Michaux (Pink Valerian, Long-tube Valerian)
  • Valerianella chenopodiifolia (Pursh) DC. (Goosefoot Corn-salad)
  • Valerianella locusta (L.) Latterade (European Corn-salad, Lamb's-lettuce)
  • Valerianella radiata (L.) Dufr. (Beaked Corn-salad)
  • Valerianella umbilicata (Sull.) Wood (Northern Corn-salad)
  • Valerianella woodsiana (T. & G.) Walp. (Woods' Corn-salad)
  • Vallisneria americana Michx. (Tapegrass, Water-celery)
  • Vandenboschia boschiana (Sturm) Ebihara & K. Iwatsuki (Appalachian Filmy Fern)
  • Veratrum viride Aiton (American False-hellebore, White Hellebore, Green Hellebore, Indian Poke)
  • Verbascum blattaria L. (Moth Mullein)
  • Verbascum lychnitis L. ssp. lychnitis (White Mullein)
  • Verbascum phlomoides L. (Clasping Mullein, Orange Mullein)
  • Verbascum thapsus L. ssp. thapsus (Common Mullein, Great Mullein Woolly Mullein, Flannel-plant, Velvet-plant)
  • Verbena bonariensis L. (Purpletop Vervain)
  • Verbena bracteata Lag.& Rodr. (Prostrate Vervain, Big-bracted Vervain)
  • Verbena brasiliensis Vell. (Brazilian Vervain)
  • Verbena hastata L. (Blue Vervain, Common Vervain)
  • Verbena incompta P.W. Michael (Purpletop Vervain)
  • Verbena officinalis L. (European Vervain)
  • Verbena rigida Spreng. (Slender Vervain, Tuberous Vervain)
  • Verbena scabra Vahl (Rough Vervain, Sandpaper Vervain)
  • Verbena simplex Lehm. (Narrow-leaf Vervain)
  • Verbena urticifolia L. (White Vervain)
  • Verbesina alternifolia (L.) Britt. ex Kearney (Wingstem)
  • Verbesina occidentalis (L.) Walt. (Yellow Crownbeard)
  • Verbesina virginica L. var. virginica (White Crownbeard, Frostweed)
  • Vernonia gigantea (Walt.) Trel. ex Brann. & Cov. (Tall Ironweed)
  • Vernonia glauca (L.) Willd. (Upland Ironweed, Broad-leaf Ironweed)
  • Vernonia noveboracensis (L.) Michx. (New York Ironweed)
  • Veronica agrestis L. (Field Speedwell)
  • Veronica americana Schwein. ex Benth. (American Speedwell, Brooklime)
  • Veronica anagallis-aquatica L. (Water Speedwell, Brook Pimpernel)
  • Veronica arvensis L. (Corn Speedwell, Wall Speedwell)
  • Veronica chamaedrys L. (Germander Speedwell)
  • Veronica dillenii Crantz (Dillenius's Speedwell)
  • Veronica hederifolia L. (Ivy-leaf Speedwell)
  • Veronica officinalis L. (Common Speedwell)
  • Veronica peregrina L. var. peregrina (Common Purslane Speedwell)
  • Veronica persica Poiret (Bird's-eye Speedwell)
  • Veronica polita Fries (Gray Field Speedwell)
  • Veronica scutellata L. (Marsh Speedwell, Skullcap Speedwell)
  • Veronica serpyllifolia L. var. serpyllifolia (Thyme-leaf Speedwell)
  • Veronica sublobata M.A. Fischer (Small Ivyleaf Speedwell)
  • Veronicastrum virginicum (L.) Farwell (Culver's-root)
  • Viburnum acerifolium L. (Maple-leaf Viburnum, Dockmackie)
  • Viburnum cassinoides L. (Northern Wild Raisin, Withe-rod)
  • Viburnum dentatum complex (Arrow-wood)
  • Viburnum dentatum L. (Southern Arrow-wood)
  • Viburnum dilatatum Thunberg (Linden Arrow-wood, Linden Viburnum)
  • Viburnum lantanoides Michx. (Hobblebush, Witch's-hobble)
  • Viburnum lentago L. (Nannyberry)
  • Viburnum nudum L. (Southern Wild Raisin, Possum-haw)
  • Viburnum opulus L. var. opulus (Guelder-rose Viburnum, Snowball)
  • Viburnum plicatum Thunb. (Japanese Snowball)
  • Viburnum prunifolium L. (Black Haw)
  • Viburnum rafinesqueanum J. A. Schultes (Downy Arrow-wood)
  • Viburnum recognitum Fernald (Smooth Arrow-wood)
  • Viburnum rhytidophyllum Hemsley (Leatherleaf Viburnum)
  • Viburnum rufidulum Raf. (Rusty Black Haw, Southern Black Haw)
  • Viburnum setigerum Hance (Tea Viburnum)
  • Viburnum sieboldii Miq. (Siebold's Viburnum)
  • Vicia americana Muhl. ex Willd. var. americana (American Vetch, Purple Vetch)
  • Vicia caroliniana Walt. (Wood Vetch, Carolina Vetch)
  • Vicia cracca L. (Tufted Vetch, Cow Vetch)
  • Vicia grandiflora Scop. (Large Yellow Vetch, Showy Vetch)
  • Vicia hirsuta (L.) S.F. Gray (Tiny Vetch, Hairy Tare)
  • Vicia lathyroides L. (Spring Vetch)
  • Vicia sativa L. (Narrow-leaf Vetch, Common Vetch)
  • Vicia tetrasperma (L.) Schreb. (Slender Vetch, Lentil Vetch)
  • Vicia villosa Roth ssp. varia (Host) Corbiere (Smooth Vetch)
  • Vicia villosa Roth ssp. villosa (Hairy Vetch, Winter Vetch)
  • Vigna luteola (Jacq.) Benth. (Wild Cow Pea)
  • Vigna unguiculata (L.) Walp. (Cow Pea)
  • Vinca major L. (Greater Periwinkle)
  • Vinca minor L. (Periwinkle, Common Periwinkle)
  • Viola affinis Le Conte (LeConte's Violet, Sand Violet)
  • Viola appalachiensis L.K. Henry (Appalachian Violet)
  • Viola arvensis Murr. (European Field Pansy)
  • Viola blanda Willd. (Sweet White Violet)
  • Viola brittoniana Pollard (Coast Violet, Northern Coast Violet)
  • Viola canadensis L. (Canada Violet, Tall White Violet)
  • Viola communis Pollard (Hooded Blue Violet, Confederate Violet)
  • Viola cucullata Ait. (Marsh Blue Violet)
  • Viola edulis Spach (Salad Violet)
  • Viola emarginata (Nutt.) Leconte (Triangle-leaved Violet)
  • Viola eriocarpa Schwein. (Smooth Yellow Violet)
  • Viola fimbriatula J.E. Smith (Northern Downy Violet)
  • Viola glaberrima (Gingins) H. House (Three-parted Violet)
  • Viola hastata Michx. (Halberd-leaved Yellow Violet)
  • Viola hirsutula Brainerd (Southern Wood Violet)
  • Viola incognita Brainerd (Large-leaved White Violet)
  • Viola labradorica Schrank (Dog-violet)
  • Viola lanceolata L. (Lance-leaved Violet, Narrow-leaved Violet)
  • Viola minuscula Greene (Smooth White Violet, Small White Violet, Northern White Violet)
  • Viola monacanora J.L.Hastings & H.E.Ballard (Blue Ridge Violet)
  • Viola odorata L. (Sweet Violet, English Violet)
  • Viola palmata L. complex (Wood Violet)
  • Viola palmata L. var. palmata (Cleft Violet)
  • Viola palmata L. var. triloba (Schwein.) Gingins ex A. DC. (Northern Three-lobed Violet)
  • Viola pectinata E.P. Bickn. (Pectinate Violet)
  • Viola pedata L. ssp. cuneatiloba (Brainerd ex Fernald) H.E.Ballard (Squirrel Corn Bird’s-foot Violet)
  • Viola pedata L. ssp. pedata (Bird's-foot violet)
  • Viola primulifolia L. (Primrose-leaved Violet)
  • Viola pubescens / eriocarpa complex (Yellow Violet)
  • Viola pubescens Aiton (Downy Yellow Violet)
  • Viola rafinesquei Greene (Field Pansy, Wild Pansy)
  • Viola rostrata Pursh (Long-spurred Violet)
  • Viola rotundifolia Michx. (Round-leaved Yellow Violet, Early Yellow Violet)
  • Viola sagittata Aiton (Arrow-leaved Violet)
  • Viola septemloba Le Conte (Southern Coastal Violet)
  • Viola septentrionalis Greene (Northern Blue Violet, Woodland Blue Violet)
  • Viola sororia Willd. (Common Blue Violet)
  • Viola stoneana House (Stone's Violet)
  • Viola striata Ait. (Striped Violet, Cream Violet)
  • Viola subsinuata Greene (Lobed Violet, Lobed Blue Violet, Wavy-leaved Violet)
  • Viola tenuisecta Zumwalde & H.E.Ballard (Virginia Shale Woodland Violet)
  • Viola tricolor L. (Pansy, Johnny-jump-up)
  • Viola vittata Greene (Bog White Violet, Strap-leaved Violet)
  • Viola walteri House (Prostrate Blue Violet, Walter's Violet)
  • Vitex agnus-castus L. (Lilac Chaste Tree)
  • Vitex rotundifolia L.f. (Beach Vitex, Round-leaf Chaste-tree)
  • Vitis aestivalis Michx. (Summer Grape, Silverleaf Grape)
  • Vitis aestivalis Michx. var. bicolor Deam (Silverleaf Grape)
  • Vitis cinerea (Engelm.) Engelm. ex Millardet var. baileyana (Munson) Comeaux (Possum Grape)
  • Vitis cinerea (Engelm.) Engelm. ex Millardet var. floridana Munson (Florida Grape)
  • Vitis labrusca L. (Fox Grape)
  • Vitis palmata Vahl (Red Grape, Cat Grape, Catbird Grape)
  • Vitis riparia Michx. (Riverbank Grape)
  • Vitis rupestris Scheele (Sand Grape)
  • Vitis vinifera L. (European Wine Grape)
  • Vitis vulpina L. (Winter Grape, Frost Grape, Chicken Grape)
  • Vittaria appalachiana Farrar & Mickel (Appalachian Shoestring Fern, Appalachian Gametophyte)
  • Vulpia bromoides (L.) S.F. Gray (European Squirrel-tail Fescue, Brome Fescue)
  • Vulpia elliotea (Raf.) Fern. (Squirrel-tail Fescue)
  • Vulpia myuros (L.) K.C. Gmel. (Rattail Fescue)
  • Vulpia octoflora (Walt.) Rydb. (Six-weeks Fescue)
  • Wahlenbergia marginata (Thunb.) A. DC. (Southern Rockbell)
  • Waldsteinia fragarioides (Michx.) Tratt. (Barren Strawberry)
  • Waldsteinia fragarioides (Michx.) Tratt. ssp. doniana (Tratt.) Teppner (Southern Barren Strawberry)
  • Waldsteinia fragarioides (Michx.) Tratt. ssp. fragarioides (Northern Barren Strawberry)
  • Warnstorfia fluitans (Hedw.) Loeske
  • Weigela floribunda (Sieb. & Zucc.) K. Koch (Crimson Weigela)
  • Weissia controversa Hedwig
  • Weissia ludoviciana (Sull.) W.D. Reese & B.A.E. Lemmon
  • Weissia muhlenbergiana (Sw.) W.D. Reese & B.A.E. Lemmon
  • Weissia phascopsis R.H. Zander
  • Weissia sharpii L.E. Anderson & B.A.E. Lemmon
  • Wisteria floribunda (Willd.) DC. (Japanese Wisteria)
  • Wisteria frutescens (L.) Poir. var. frutescens (American Wisteria, Atlantic Wisteria)
  • Wisteria frutescens (L.) Poir. var. macrostachya Torr. & A. Gray (Mississippi Wisteria)
  • Wisteria sinensis (Sims) Sweet (Chinese Wisteria)
  • Wolffia borealis (Engelm.) Landolt (Northern Watermeal)
  • Wolffia brasiliensis Weddell (Brazilian Watermeal, Pointed Watermeal)
  • Wolffia columbiana Karst. (Columbian Watermeal)
  • Wolffiella gladiata (Hegelm.) Hegelm. (Sword Bogmat, Mud-midget)
  • Woodsia appalachiana T.M.C. Taylor (Appalachian Woodsia, Appalachian Cliff Fern, Mountain Woodsia)
  • Woodsia ilvensis (L.) R. Br. (Rusty Woodsia, Rusty Cliff Fern)
  • Woodsia obtusa (Spreng.) Torr. ssp. obtusa (Blunt-lobed Woodsia, Blunt-lobed Cliff Fern)
  • Xanthium spinosum L. (Spiny Cocklebur)
  • Xanthium strumarium L. (Common Cocklebur)
  • Xanthorhiza simplicissima Marsh. (Yellowroot)
  • Xerophyllum asphodeloides (L.) Nutt. (Turkeybeard, Beargrass)
  • Xyris ambigua Beyrich ex Kunth (Coastal Plain Yellow-eyed Grass)
  • Xyris caroliniana Walter (Carolina Yellow-eyed Grass, Pineland Yellow-eyed Grass)
  • Xyris curtisii Malme (Curtiss' Yellow-eyed Grass)
  • Xyris difformis Chapman (Bog Yellow-eyed Grass)
  • Xyris fimbriata Elliott (Fringed Yellow-eyed Grass)
  • Xyris iridifolia Chapman (Iris-leaf Yellow-eyed Grass)
  • Xyris jupicai L.C.Richard (Richard's Yellow-eyed Grass)
  • Xyris platylepis Chapman (Tall Yellow-eyed Grass)
  • Xyris torta J.M. Smith (Twisted Yellow-eyed Grass)
  • Youngia japonica (L.) DC. (Oriental False Hawksbeard, Asiatic False Hawksbeard)
  • Youngia thunbergiana DC. (Tall False Hawksbeard)
  • Yucca aloifolia L. (Spanish Dagger)
  • Yucca filamentosa L. (Common Yucca, Adam's Needle)
  • Yucca flaccida Haworth (Weakleaf Yucca)
  • Yucca gloriosa L. (Mound-lily Yucca, Spanish Bayonet)
  • Zannichellia palustris L. (Horned Pondweed)
  • Zanthoxylum americanum P. Mill. (Toothache Tree, Northern Prickly-ash, Common Prickly-ash)
  • Zanthoxylum clava-herculis L. (Hercules'-club)
  • Zea mays L. ssp. mays (Corn, Maize)
  • Zelkova serrata (Thunb.) Makino (Zelkova)
  • Zenobia pulverulenta (Bartr. ex Willd.) Pollard (Dusty Zenobia, Honeycup)
  • Zephyranthes atamasco (L.) Herbert (Common Atamasco-lily)
  • Zigadenus glaberrimus Michx. (Large Death-camas, Snakeroot)
  • Zizania aquatica L. var. aquatica (Wild Rice)
  • Zizaniopsis miliacea (Michx.) Doell & Aschers. (Southern Wild Rice, Giant Cutgrass)
  • Zizia aptera (Gray) Fern. (Heart-leaf Golden-alexanders)
  • Zizia aurea (L.) W.D.J. Koch (Golden-alexanders, Common Golden-alexanders)
  • Zizia trifoliata (Michx.) Fern. (Mountain Golden-alexanders)
  • Zornia bracteata J.F. Gmel. (Viperina)
  • Zostera marina L. (Eelgrass, Sea-wrack)
  • Zygodon viridissimus (Dickson) Brid. var. rupestris Lindb.

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