List of endangered flora of Connecticut

Flora of Connecticut that are considered endangered species.

Key
 * E - Endangered
 * T - Threatened
 * SC - Special Concern
 * SCE - Special Concern, believed extirpated

Adoxaceae (Moschatel family)

 * Viburnum nudum (Possum haw, SCE)
 * Viburnum prunifolium (Smooth black-haw, T)

Alismataceae (Water-plaintain family)

 * Echinodorus tenellus (Bur-head, E) a.k.a.  Helanthium tenellum
 * Sagittaria cuneata (Northern arrowhead, E)
 * Sagittaria subulata (Awl-leaved arrowhead, SC)
 * Sagittaria teres (Quill-leaved arrowhead, E)

Amaranthaceae (Amaranth family)

 * Amaranthus pumilus (Sea-beach amaranth, SCE, federally threatened)
 * Atriplex glabriuscula (Bracted orache, SC)
 * Chenopodium rubrum (Red goosefoot, SCE) a.k.a. Oxybasis rubra

Anacardiaceae (Cashew or sumac family)

 * Rhus aromatica (Fragrant sumac, SCE, Native populations only)

Apiaceae a.k.a. Umbelliferae (Celery, carrot or parsley family)

 * Angelica lucida (Sea-coast angelica, E)
 * Angelica venenosa (Hairy angelica, SCE)
 * Ligusticum scoticum (Scotch lovage, E)
 * Lilaeopsis chinensis (Lilaeopsis, SC)
 * Taenidia integerrima (Yellow pimpernel, E)
 * Zizia aptera (Golden Alexanders, E)

Apocynaceae (Dogbane family)

 * Asclepias purpurascens (Purple milkweed, SC)
 * Asclepias variegata (White milkweed, SCE)
 * Asclepias viridiflora (Green milkweed) (E)

Araceae (Arum or aroid family)

 * Orontium aquaticum (Golden club, SC)

Araliaceae (Aralia or ivy family)

 * Hydrocotyle umbellata (Water pennywort, E)
 * Hydrocotyle verticillata (Whorled pennywort, E)
 * Panax quinquefolius (American ginseng, SC)

Aristolochiaceae (Birthwort family)

 * Endodeca serpentaria (Virginia snakeroot, SC a.k.a. Aristolochia serpentaria)

Aquifoliaceae (Holly family)

 * Ilex glabra (Inkberry, T, native populations only)

Asparagaceae

 * Maianthemum trifolium (Three-leaved false Solomon's-seal, T)

Aspleniaceae

 * Asplenium montanum (Mountain spleenwort, SC)
 * Asplenium ruta-muraria (Wallrue spleenwort, T)
 * Diplazium pycnocarpon (Narrow-leaved glade fern, E)

Asteraceae (Aster, daisy, composite, or sunflower family)

 * Ageratina aromatica (Small white snakeroot, E)
 * Antennaria howellii ssp. petaloidea (Field pussytoes, SCE)
 * Bidens beckii (Beck's water-marigold, SC)
 * Bidens eatonii (Eaton's beggarticks, E)
 * Cirsium horridulum (Yellow thistle, E)
 * Doellingeria infirma (Appalachian white-aster, SCE)
 * Eupatorium album (White thoroughwort, E)
 * Eurybia radula (Rough aster, E)
 * Eurybia spectabilis (Showy aster, T)
 * Gamochaeta purpurea (Purple cudweed, SCE)
 * Krigia biflora (Two-flowered cynthia, T)
 * Liatris novae-angliae (New England blazing-star, SC)
 * Oclemena nemoralis (Bog aster, E)
 * Oligoneuron album (Prairie goldenrod, a.k.a.  Solidago ptarmicoides, E)
 * Oligoneuron rigidum (Stiff goldenrod, a.k.a. Solidago rigida, E)
 * Packera anonyma (Small's ragwort, E)
 * Packera paupercula (Balsam groundsel, E)
 * Petasites frigidus var. palmatus  (Sweet coltsfoot, T)
 * Pityopsis falcata (Sickle-leaved golden aster, E)
 * Polymnia canadensis (Small-flowered leafcup, E)
 * Senecio suaveolens (Sweet-scented Indian-plantain, E)
 * Solidago aestivalis (Early wrinkle-leaved goldenrod, SCE, also called rugosa)
 * Solidago latissimifolia (Elliott's goldenrod, SCE)
 * Symphyotrichum prenanthoides (Crooked-stem aster, SCE)

Betulaceae (Birch family)

 * Betula pumila (Swamp birch, T)

Boraginaceae (Borage or forget-me-not family)

 * Cynoglossum virginianum (Wild comfrey, SC)
 * Hydrophyllum virginianum (Virginia waterleaf, SC)
 * Onosmodium virginianum (Gravel-weed E, a.k.a. Lithospermum virginianum)

Brassicaceae (Mustards, crucifers, or cabbage family)

 * Cardamine douglassii (Purple cress, SC)
 * Draba reptans (Whitlow-grass, SC)

Cactaceae (Cactus family)

 * Opuntia humifusa (Eastern prickly pear, SC)

Caprifoliaceae (Honeysuckle family)

 * Linnaea borealis ssp. americana (Twinflower, E)
 * Triosteum angustifolium (Narrow-leaved horse gentian, E)
 * Valerianella radiata (Beaked corn-salad, SCE)

Caryophyllaceae (Pink or carnation family)

 * Honckenya peploides (Seabeach sandwort, SC)
 * Minuartia glabra (Mountain sandwort, E)
 * Moehringia macrophylla (Large-leaved sandwort, E)
 * Paronychia fastigiata (Hairy forked chickweed, SCE)
 * Silene stellata (Starry campion, T)
 * Spergularia canadensis (Canada sand-spurry, T)
 * Stellaria borealis (Northern stitchwort, SC)

Celastraceae (Staff vine or bittersweet family)

 * Celastrus scandens (American bittersweet, SC)

Cistaceae (Rock rose or Rock-rose family)

 * Crocanthemum dumosum (Bushy frostweed, SCE a.k.a. Helianthemum dumosum)
 * Crocanthemum propinquum (Low frostweed, SC a.k.a. Helianthemum propinquum)
 * Hudsonia ericoides (Golden heather, E)
 * Hudsonia tomentosa (Woolly beach-heather, T)
 * Lechea racemulosa (Illinois pinweed, SCE)

Cleomaceae

 * Polanisia dodecandra (Clammy-weed, SCE)

Colchicaceae

 * Uvularia grandiflora (Large-flowered bellwort, E)

Convolvulaceae (Bindweed or morning glory family)

 * Calystegia silvatica (Short-stalked false bindweed, SCE)
 * Calystegia spithamaea (Low bindweed, SCE)
 * Cuscuta coryli (Hazel dodder, SCE)

Crassulaceae (Stonecrop or orpine family)

 * Crassula aquatica (Pygmyweed, E)

Cupressaceae (Cypress family)

 * Thuja occidentalis (Northern white cedar, native populations only, T)

Cyperaceae (Sedge family)

 * Bolboschoenus maritimus ssp. paludosus (Bayonet Grass, SC)
 * Bolboschoenus novae-angliae (Salt marsh bulrush, SC)
 * Carex aestivalis (Summer sedge, SC)
 * Carex alata (Broadwing sedge, E)
 * Carex alopecoidea (Foxtail sedge T)
 * Carex aquatilis ssp. altior (Water sedge, SC)
 * Carex backii (Back's sedge, E)
 * Carex barrattii (Barratt's sedge, E)
 * Carex bushii (Bush's sedge, SC)
 * Carex buxbaumii (Brown bog sedge, E)
 * Carex castanea (Chestnut-colored sedge, E)
 * Carex collinsii (Collins' sedge, SCE)
 * Carex crawei (Crawe's sedge, T)
 * Carex crawfordii (Crawford sedge, SCE)
 * Carex cumulata (Clustered Sedge, T)
 * Carex davisii (Davis' sedge, T)
 * Carex foenea (Bronze sedge, SC a.k.a. Carex siccata)
 * Carex formosa (Handsome sedge, T)
 * Carex hitchcockiana (Hitchcock's sedge, SC)
 * Carex limosa (Mud sedge, T)
 * Carex magellanica (Boreal bog sedge, E)
 * Carex molesta (Troublesome sedge, SC)
 * Carex nigromarginata (Black-edge sedge, SCE)
 * Carex novae-angliae (New England sedge, SC)
 * Carex oligocarpa (Eastern few-fruit sedge, SC)
 * Carex oligosperma (Few-seeded sedge, SCE)
 * Carex pauciflora (Few-flowered sedge, SCE)
 * Carex polymorpha (Variable sedge, E)
 * Carex prairea (Prairie sedge, SC)
 * Carex pseudocyperus (Cyperus-like sedge, E)
 * Carex reznicekii (Reznicek's sedge, E)
 * Carex schweinitzii (Schweinitz's sedge, E)
 * Carex siccata (Bronze sedge, SC)
 * Carex sterilis (Dioecious sedge, SC)
 * Carex trichocarpa (Hairy-fruited sedge, SC)
 * Carex tuckermanii (Tuckerman's sedge, SC)
 * Carex typhina (Cattail sedge, SC)
 * Carex viridula (Little green sedge, E)
 * Carex willdenowii (Willdenow's sedge, E)
 * Eleocharis equisetoides (Horsetail spikesedge, E)
 * Eleocharis microcarpa var. filiculmis (Small-fruited spikesedge, SCE)
 * Eleocharis quadrangulata var. crassior (Square-stemmed spikesedge, E)
 * Eriophorum vaginatum var. spissum (Hare's tail, T)
 * Lipocarpha micrantha (Dwarf bulrush, T)
 * Rhynchospora capillacea (Needle beaksedge, E)
 * Rhynchospora macrostachya (Tall beaksedge, T)
 * Rhynchospora scirpoides (Long-beaked beaksedge, E)
 * Schoenoplectus acutus (Hard-stemmed bullrush, T)
 * Schoenoplectus torreyi (Torrey bulrush, T)
 * Scirpus georgianus (Georgia bulrush, SCE)
 * Scirpus longii (Long's bulrush, SCE)
 * Scleria pauciflora var. caroliniana (Few-flowered nutrush, E)
 * Scleria reticularis (Reticulated nutrush, E)
 * Scleria triglomerata (Whip nutrush, E)
 * Scleria verticillata (Low nutrush, SCE)
 * Trichophorum alpinum (Alpine bulrush, SCE)

Droseraceae (Sundew family)

 * Drosera filiformis (Thread-leaf sundew, SCE)

Dryopteridaceae (Wood fern family)

 * Dryopteris campyloptera (Mountain wood-fern, E)
 * Dryopteris goldieana (Goldie's fern, SC)

Equisetaceae (Horsetail family)

 * Equisetum palustre (Marsh horsetail, SCE)
 * Equisetum pratense (Meadow horsetail, E)
 * Equisetum scirpoides (Dwarf scouring rush, E)

Ericaceae (Heath or heather family)

 * Andromeda polifolia var. glaucophylla (Bog rosemary, T)
 * Gaultheria hispidula (Creeping snowberry, SC)
 * Gaylussacia bigeloviana (Dwarf huckleberry, T)
 * Lyonia mariana (Stagger-bush, SCE)
 * Moneses uniflora (One-flower wintergreen, E)
 * Orthilia secunda (One-sided pyrola, SCE)
 * Rhododendron groenlandicum (Labrador tea, T)
 * Vaccinium myrtilloides (Velvetleaf blueberry, E,)
 * Vaccinium vitis-idaea ssp. minus (Mountain cranberry, SCE)

Eriocaulaceae (Pipewort family)

 * Eriocaulon parkeri (Parker's pipewort, E)

Euphorbiaceae (Spurge family)

 * Acalypha virginica (Virginia copperleaf, SC)
 * Crotonopsis elliptica (Elliptical rushfoil, SCE)

Fabaceae (Legume, pea, or bean family)

 * Desmodium cuspidatum (Large-bracted tick-trefoil, E)
 * Desmodium glabellum (Dillenius’ tick-trefoil, SC)
 * Desmodium sessilifolium (Sessile-leaf tick-trefoil, SCE)
 * Lespedeza repens (Creeping bush-clover, SC)
 * Phaseolus polystachios var. polystachios (Wild kidney bean, SCE)
 * Senna hebecarpa (Wild senna, T)

Fagaceae

 * Quercus macrocarpa (Bur Oak, SC)

Gentianaceae

 * Gentianella quinquefolia (Stiff gentian, E)
 * Sabatia dodecandra (Large marsh pink, SCE)
 * Sabatia stellaris (Marsh pink, E)

Geraniaceae

 * Geranium bicknellii (Bicknell's northern crane's-bill, SCE)

Grossulariaceae

 * Ribes glandulosum (Skunk currant, SC)
 * Ribes lacustre (Swamp black current, SCE)
 * Ribes rotundifolium (Wild current, SC)
 * Ribes triste (Swamp red currant, E)

Haemodoraceae (Bloodwort family)

 * Lachnanthes caroliniana (Carolina redroot native populations only, E)

Haloragaceae (Water-milfoil family)

 * Myriophyllum alterniflorum (Slender water-milfoil, E)
 * Myriophyllum pinnatum (Cutleaf water-milfoil, E)
 * Myriophyllum sibiricum (Northern water-milfoil, T)

Hymenophyllaceae (Filmy ferns and bristle ferns)

 * Trichomanes intricatum (Appalachian gametophyte, SC)

Hypericaceae

 * Hypericum adpressum (Creeping St. John's-wort, SCE)
 * Hypericum ascyron (Great St. John's-wort, SC)

Juncaceae (Rush family)

 * Juncus debilis (Weak rush, SCE)

Lamiaceae (Mint or deadnettle family)

 * Agastache nepetoides (Yellow giant hyssop, E)
 * Agastache scrophulariifolia (Purple giant hyssop, E)
 * Blephilia ciliata (Downy wood-mint, SCE)
 * Blephilia hirsuta (Hairy wood-mint, SCE)
 * Lycopus amplectens (Clasping-leaved water-horehound, SC)
 * Pycnanthemum torreyi (Torrey mountain-mint, E)
 * Stachys hispida (Hispid hedge-nettle, T)
 * Stachys hyssopifolia (Hyssop-leaf hedge-nettle, E)
 * Scutellaria integrifolia (Hyssop skullcap, E)
 * Scutellaria parvula var. missouriensis (Small skullcap, E)
 * Trichostema brachiatum (False pennyroyal, E)

Lentibulariaceae (Bladderwort family)

 * Utricularia resupinata (Resupinate bladderwort, E)

Liliaceae (Lily family)

 * Streptopus amplexifolius (White mandarin, T)

Limnanthaceae

 * Floerkea proserpinacoides (False mermaid-weed, E)

Linaceae

 * Linum intercursum (Sandplain flax, SCE)
 * Linum sulcatum (Yellow flax, E)

Lycopodiaceae

 * Huperzia appressa (Fir clubmoss, SCE)
 * Lycopodiella alopecuroides (Foxtail clubmoss, E)

Lygodiaceae

 * Lygodium palmatum (Climbing fern, SCE)

Lythraceae

 * Cuphea viscosissima (Blue waxweed, SCE)
 * Lythrum alatum (Winged loosestrife, E)
 * Rotala ramosior (Toothcup, T)

Melanthiaceae

 * Chamaelirium luteum (Devil's bit, E)
 * Veratrum latifolium (Hybrid bunchflower, SCE)

Nymphaeaceae (Water-lily family)

 * Nuphar advena (Large yellow pond lily, SCE)
 * Nuphar microphylla (Small yellow pond lily, SCE)

Onagraceae (Primrose or willowherb family)

 * Ludwigia polycarpa (Many-fruited false-loosestrife, SCE)
 * Ludwigia sphaerocarpa (Globe-fruited false-loosestrife, E)
 * Oenothera fruticosa (Sundrops, SCE)

Orchidaceae (Orchid family)

 * Aplectrum hyemale (Puttyroot, SCE)
 * Arethusa bulbosa (Dragon's-mouth, SCE)
 * Coeloglossum viride (Long-bracted green orchid, E)
 * Corallorhiza trifida (Early coral root, SC)
 * Cypripedium arietinum (Ram's-head lady's-slipper, SCE)
 * Cypripedium parviflorum (Yellow lady's-slipper, SC)
 * Cypripedium reginae (Showy lady's-slipper, SC)
 * Goodyera repens var. ophioides (Dwarf rattlesnake plantain, SCE)
 * Isotria medeoloides (Small whorled pogonia, E, federally threatened)
 * Liparis liliifolia (Lily-leaved twayblade, E)
 * Malaxis bayardii (Bayard's white adder's mouth, SCE)
 * Malaxis brachypoda (White adder's-mouth, E)
 * Malaxis unifolia (Green adder's-mouth, E)
 * Platanthera blephariglottis (White-fringed orchid, E)
 * Platanthera ciliaris (Yellow-fringed orchid, E)
 * Platanthera dilatata (Tall white bog orchid, SCE)
 * Platanthera flava var. herbiola (Pale green orchid, SC)
 * Platanthera hookeri (Hooker's orchid, SCE)
 * Platanthera orbiculata (Large round-leaved orchid, SCE)
 * Triphora trianthophora (Nodding pogonia, E)
 * Spiranthes tuberosa var. grayi (Little ladies’-tresses, SC)

Ophioglossaceae (Adder's-tongue family)

 * Botrychium simplex (Little grape fern, SCE)
 * Ophioglossum pusillum (Northern adder's-tongue, E)
 * Ophioglossum vulgatum (Southern adder's-tongue, E)

Orobanchaceae (Broomrape family)

 * Agalinis acuta (Sandplain agalinis, E, Federally Endangered)
 * Castilleja coccinea (Indian paintbrush, E)
 * Pedicularis lanceolata (Swamp lousewort, T)
 * Schwalbea americana (Chaffseed, SCE, federally endangered)

Oxalidaceae (Wood sorrel family)

 * Oxalis violacea (Violet wood-sorrel, SC)

Papaveraceae (Poppy family)

 * Corydalis flavula (Yellow corydalis, T)
 * Dicentra canadensis (Squirrel corn, SC)

Plantaginaceae (Plantain family)

 * Plantago virginica (Hoary plantain, SC)

Pinaceae (Pine family)

 * Abies balsamea (Balsam fir, E, native populations only)
 * Pinus resinosa (Red pine, E, native populations only)

Poaceae (Grasses family)

 * Alopecurus aequalis (Short-awned meadow-foxtail, T)
 * Aristida longespica var. geniculata (Needlegrass, SC)
 * Aristida purpurascens (Arrowfeather, E)
 * Aristida tuberculosa (Beach needle grass, E)
 * Bouteloua curtipendula (Sideoats grama-grass, E)
 * Calamagrostis stricta ssp. inexpansa (Bend reedgrass, T)
 * Coleataenia longifolia ssp. elongata (SCE)
 * Deschampsia cespitosa (Tufted hairgrass, SC)
 * Dichanthelium ovale ssp. pseudopubescens (Stiff-leaved rosette-panicgrass, SCE)
 * Dichanthelium scabriusculum (Tall swamp rosette-panicgrass, E)
 * Dichanthelium sphaerocarpon var. isophyllum (Round-fruited rosette panicgrass, SCE)
 * Dichanthelium xanthophysum (Pale-leaved rosette-panicgrass, SCE)
 * Leptochloa fusca ssp. fascicularis (Saltpond grass, E)
 * Milium effusum (Tall millet-grass, E)
 * Muhlenbergia capillaris (Long-awn hairgrass, E)
 * Panicum amarum var. amarum (Bitter panicgrass, T)
 * Panicum verrucosum (Warty panicgrass, SCE)
 * Paspalum laeve (Field paspalum, T)
 * Paspalum setaceum var. psammophilum (Thin paspalum, SCE)
 * Piptatherum pungens (Slender mountain ricegrass, E)
 * Phragmites americanus (American reed, SC)
 * Puccinellia pumila (Goose grass, SCE)
 * Schizachne purpurascens (Purple oat, SC)
 * Sporobolus clandestinus (Rough dropseed, E)
 * Sporobolus cryptandrus (Sand dropseed, T)
 * Sporobolus heterolepis (Northern dropseed, E)
 * Sporobolus neglectus (Small dropseed, E)
 * Trisetum spicatum (Narrow false oats, E)

Polygalaceae (Milkwort family)

 * Polygala ambigua (Alternate milkwort, SC)
 * Polygala cruciata (Field milkwort, E)
 * Polygala nuttallii (Nuttall's milkwort, T)
 * Polygala senega (Seneca snakeroot, E)

Polygonaceae (Knotweed, smartweed, or buckwheat family)

 * Polygonum glaucum (Seabeach knotweed, SC)
 * Rumex persicarioides (Sea-side dock, SCE)

Pontederiaceae

 * Heteranthera reniformis (Kidneyleaf mud-plantain, SCE)

Potamogetonaceae (Pondweed family)

 * Potamogeton confervoides (Tuckerman's pondweed, E)
 * Potamogeton friesii (Fries' pondweed, E)
 * Potamogeton gemmiparus (Capillary pondweed, T)
 * Potamogeton hillii (Hill's pondweed, E)
 * Potamogeton ogdenii (Ogden's pondweed, E)
 * Potamogeton strictifolius (Straight-leaved pondweed, E)
 * Potamogeton vaseyi (Vasey's pondweed, T)

Primulaceae (Primrose family)

 * Hottonia inflata (Featherfoil, SC)

Pteridaceae

 * Cheilanthes lanosa (Hairy lip-fern, E)
 * Cryptogramma stelleri (Slender cliff-brake, E)
 * Pellaea glabella (Smooth cliff-brake, E)

Ranunculaceae (Buttercup or crowfoot family)

 * Anemone acutiloba (Sharp-lobed hepatica, SC)
 * Anemone canadensis (Canada anemone, T)
 * Hydrastis canadensis (Goldenseal, E)
 * Ranunculus ambigens (Water-plantain spearwort, E)
 * Ranunculus cymbalaria (Seaside crowfoot, E)
 * Ranunculus flammula var. reptans (Creeping spearwort, SCE)
 * Ranunculus pensylvanicus (Bristly buttercup, SC)
 * Trollius laxus (Spreading globe flower, T)

Rosaceae (Rose family)

 * Drymocallis arguta (Tall cinquefoil, SC)
 * Prunus alleghaniensis (Alleghany plum, SCE)
 * Prunus maritima var. gravesii (Graves beach plum, SCE)
 * Rosa nitida (Shining rose, SCE)
 * Rubus cuneifolius (Sand blackberry, SC)
 * Rubus dalibarda (Dew-drop, E, Now called Dalibarda repens)
 * Sibbaldiopsis tridentata (Three-toothed cinquefoil, T)
 * Waldsteinia fragarioides (Barren strawberry, E)

Rubiaceae, (Coffee, madder, or bedstraw family)

 * Galium labradoricum (Bog bedstraw, E)
 * Houstonia longifolia (Longleaf bluet, T)

Salicaceae (Willow family)

 * Populus heterophylla (Swamp cottonwood, T)
 * Salix exigua (Sandbar willow, E)
 * Salix pedicellaris (Bog willow, E)
 * Salix petiolaris (Slender willow, SC)

Santalaceae (Sandalwood family)

 * Arceuthobium pusillum (Dwarf mistletoe, E)

Saururaceae (Lizard tail family)

 * Saururus cernuus (Lizard's Tail, E)

Saxifragaceae

 * Mitella nuda (Naked miterwort, SC)

Scheuchzeriaceae

 * Scheuchzeria palustris ssp. Americana (Pod grass, E)

Scrophulariaceae (Figwort family)

 * Limosella australis (Mudwort, SC)

Smilacaceae (Greenbrier family)

 * Smilax hispida (Bristly greenbriar, SCE)

Typhaceae

 * Sparganium fluctuans (Floating bur-reed, E)
 * Sparganium natans (Small bur-reed, E)

Verbenaceae (Verbena or vervain family)

 * Verbena simplex (Narrow-leaved vervain, SC)

Violaceae (Violet family)

 * Hybanthus concolor (Green violet, SCE)
 * Viola adunca (Hook-spurred violet, E)
 * Viola brittoniana (Coast violet, E)
 * Viola canadensis (Canada violet, SC)
 * Viola hirsutula (Southern wood violet, SCE)
 * Viola nephrophylla (Northern bog violet, SC)
 * Viola renifolia (Kidney-leaf white violet, E)
 * Viola selkirkii (Great-spurred violet, SC)

Xyridaceae

 * Xyris montana (Northern yellow-eyed grass, T)
 * Xyris smalliana (Small's yellow-eyed, E)