Maine Rare Plant List and Rare Plant Fact Sheets

Species with an asterisk (*) are not currently known to be extant in Maine. Species with a dagger (†) have had recent scientific name changes based on Flora Novae Angliae (Haines 2011), which is the taxonomic reference for plant taxa in Maine. The printable PDF includes an appendix noting recent name changes. The spreadsheet (Excel) has two worksheets: the 2015 list and a list of name changes.

Downloadable/Printable Versions: 2015 Tracking List - PDF version | 2015 Tracking List - Excel version

Scientific Name Common Name State Rank Global Rank State Status
Acalypha virginica * Three-seeded mercury SH G5 PE
Adiantum aleuticum Aleutian maidenhair fern S1 G5? E
Adlumia fungosa Allegheny vine S1 G4 E
Agalinis maritima Saltmarsh false-foxglove S3 G5 SC
Agalinis neoscotica Nova Scotia false-foxglove S1 G4 T
Agalinis purpurea Large-purple false-foxglove S1 G5 E
Agrostis mertensii Boreal bentgrass S2 G5 T
Aletris farinosa * Unicorn root SX G5 PE
Allium canadense Wild garlic S2 G5 SC
Allium tricoccum Wild leek S3 G5 SC
Amelanchier gaspensis Gaspé shadbush S2 G5T4? SC
Amelanchier nantucketensis Nantucket shadbush S2 G3Q T
Amerorchis rotundifolia Small round-leaved orchis S2 G5 T
Anemone acutiloba * † Sharp-lobed hepatica SX G5T5 PE
Anemone multifida Cut-leaved anemone S1 G5 T
Anthoxanthum monticola Alpine sweet grass S1 G5 T
Arctous alpina Alpine-bearberry S1 G5 T
Arnica lanceolata Hairy arnica S2 G3 T
Artemisia campestris ssp. canadensis * † Canadian wormwood SH G5T5 PE
Artemisia campestris ssp. caudata Beach wormwood S1S2 G5T5 SC
Asarum canadense Wild ginger S1S2 G5 T
Asclepias tuberosa * Butterfly weed SX G5? PE
Asplenium platyneuron Ebony spleenwort S2 G5 SC
Asplenium rhizophyllum * Walking fern SX G5 PE
Asplenium viride Green spleenwort S1 G4 E
Astragalus alpinus var. brunetianus Alpine milk-vetch S3 G5T3 SC
Astragalus eucosmus * Elegant milk-vetch SX G5 PE
Astragalus robbinsii var. minor Robbins' milk-vetch S1 G5T5 E
Aureolaria pedicularia Fern-leaved false foxglove S3 G5 SC
Baptisia tinctoria * Yellow wild indigo S1 G5 PE
Barbarea orthoceras * American winter-cress SH G5 PE
Bartonia paniculata Screwstem S1 G5 T
Benthamidia florida Flowering dogwood S1 G5 E
Betula glandulosa Tundra dwarf birch S1 G5 E
Betula minor Dwarf white birch S1 G4Q E
Betula pumila Swamp birch S2S3 G5 SC
Bidens eatonii Eaton's bur-marigold S2 G2G3 SC
Bidens hyperborea Estuary bur-marigold S3 G4 SC
Bistorta vivipara Alpine bistort S1 G5 E
Boechera laevigata Smooth rockcress S1 G5 T
Boechera missouriensis Missouri rockcress S1 G5?Q T
Bolboschoenus novae-angliae Marsh bulrush S1 G5 E
Bolboschoenus robustus Saltmarsh bulrush S2 G5 SC
Botrychium lunaria Moonwort S1 G5 E
Botrychium oneidense Blunt-lobed grape fern SU G4Q T
Botrychium pallidum Pale moonwort S1 G3 E
Bromus kalmii Wild chess S1 G5 E
Bromus pubescens Hairy wood brome-grass S2 G5 SC
Calamagrostis cinnoides Small reed grass S3 G5 SC
Calamagrostis pickeringii Pickering's reed grass S1 G4 T
Calamagrostis stricta ssp. inexpansa Northern reed grass S1 G5T5 E
Calamagrostis stricta ssp. stricta Neglected reed grass S2 G5T5 T
Callitriche terrestris Terrestrial water-starwort SU G5 SC
Calystegia spithamaea Upright bindweed S2 G4G5 T
Cardamine bellidifolia Alpine bitter-cress S1 G5 E
Cardamine concatenata Cut-leaved toothwort S1 G5 E
Cardamine longii Long's bitter-cress S2 G3 T
Cardamine maxima Large toothwort S3 G5 SC
Carex adusta Swarthy sedge S2 G5 E
Carex alopecoidea * Foxtail sedge SH G5 PE
Carex atherodes Awned sedge S1 G5 T
Carex atratiformis Black sedge S2S3 G5 SC
Carex baileyi * Bailey's sedge SH G4 PE
Carex bicknellii Bicknell's sedge S1 G5 E
Carex bigelowii Bigelow's sedge S2 G5 SC
Carex bullata Button sedge S2 G5 SC
Carex bushii * Bush's sedge SX G4 PE
Carex capillaris Capillary sedge S2 G5 SC
Carex crawei * Crawe's sedge SX G5 PE
Carex eburnea Ebony sedge S1 G5 E
Carex garberi Garber's sedge S2 G5 SC
Carex granularis Meadow sedge S1 G5 T
Carex gynocrates Northern bog sedge S2 G5 SC
Carex hirtifolia Pubescent sedge S2 G5 SC
Carex laevivaginata Smooth-sheathed sedge S1 G5 SC
Carex laxiculmis Spreading sedge S2 G5 E
Carex livida Livid sedge S2 G5T5 SC
Carex media Intermediate sedge S1 G5T5? E
Carex muehlenbergii var. muehlenbergii Muhlenberg sedge S1 G5 E
Carex oronensis Orono sedge S3 G3 T
Carex polymorpha Variable sedge S1 G3 E
Carex prairea Prairie sedge S1 G5? T
Carex praticola * Northern meadow sedge SX G5 PE
Carex rariflora * Loose-flowered sedge SH G5 PE
Carex recta * Saltmarsh sedge SH G4 PE
Carex rostrata Beaked sedge S2 G5 SC
Carex saxatilis Russett sedge S1 G5 E
Carex scirpoidea Bulrush sedge S2 G5 SC
Carex siccata Dry land sedge S2 G5 SC
Carex sparganioides Bur-reed sedge S1 G5 E
Carex sterilis Dioecious sedge S3 G4 SC
Carex tenuiflora Sparse-flowered sedge S3 G5 SC
Carex typhina Cattail sedge S1 G5 E
Carex vacillans Brackish sedge S2 GNR E
Carex vestita Clothed sedge S1 G5 E
Carex waponahkikensis Dawn-land sedge SNR GNR SC
Carya cordiformis Bitternut hickory S1 G5 E
Castanea dentata American chestnut S4 G4 SC
Castilleja septentrionalis Northern painted cup S3 G5 SC
Ceanothus americanus New Jersey tea S1S2 G5 T
Cenchrus longispinus * Long-spined sandbur SH G5 PE
Chamaecyparis thyoides Atlantic white cedar S2 G4 SC
Chenopodium foggii Fogg's goosefoot S1 G3Q T
Chenopodium rubrum var. rubrum * Coast-blite goosefoot SH G5 PE
Chimaphila maculata Spotted wintergreen S2 G5 T
Cirsium horridulum * Yellow thistle SH G5 PE
Clematis occidentalis ssp. occidentalis Purple clematis S3 G5T5 SC
Clethra alnifolia Sweet pepper-bush S2 G5 SC
Coptidium lapponicum Lapland buttercup S2 G5 T
Corallorhiza odontorhiza Autumn coral-root S1 G5 E
Crassula aquatica Pygmyweed S2S3 G5 SC
Cryptogramma stelleri Slender cliffbrake S1 G5 T
Cryptotaenia canadensis * Wild chervil SH G5 PE
Cynoglossum virginianum ssp. boreale Northern wild comfrey S1 G5T4T5 E
Cyperus erythrorhizos Red-root flatsedge SH G5 E
Cyperus houghtonii * Houghton's flatsedge SH G4? PE
Cyperus squarrosus Awned flatsedge S2 G5 SC
Cypripedium arietinum Ram's-head lady's-slipper S1 G3 E
Cypripedium reginae Showy lady's-slipper S3 G4 SC
Descurainia incana * Richardson's tansy-mustard SH G5T5? PE
Diapensia lapponica Lapland diapensia S2 G5 SC
Dicentra canadensis Squirrel-corn S1 G5 T
Diphasiastrum sitchense Alaskan clubmoss S1 G5 T
Draba arabisans Rock whitlow-grass S1 G4 T
Draba cana Lance-leaved draba S1 G5 E
Draba glabella Smooth whitlow-grass S1 G4G5 E
Drosera anglica English sundew S1 G5 E
Drosera linearis Slender-leaved sundew S1 G4 E
Dryopteris filix-mas ssp. brittonii Male wood fern S1 G5 E
Dryopteris fragrans Fragrant wood fern S3 G5 SC
Dryopteris goldiana Goldie's wood fern S2 G4 SC
Eleocharis aestuum Bay spikerush S2 G3 SC
Eleocharis engelmannii * Engelmann's spikerush SH G4G5Q PE
Eleocharis nitida Slender spikerush SU G3G4 SC
Eleocharis quinqueflora ssp. fernaldii Few-flowered spikerush S2 G5 SC
Eleocharis rostellata Beaked spikerush S1 G5 T
Eleocharis tuberculosa Long-tubercled spikerush S1 G5 E
Elymus hystrix Bottlebrush grass S3 G5 SC
Elymus macgregorii MacGregor's wild rye S2 GNR SC
Epilobium anagallidifolium Alpine willow-herb S1 G5 E
Epilobium hornemannii Hornemann's willow-herb S1 G5 E
Epilobium lactiflorum * White-flower willow-herb SH G5 PE
Eragrostis capillaris * Tiny lovegrass SH G5 PE
Eragrostis hypnoides* Teal lovegrass SH G5 PE
Erigeron acris ssp. kamtschaticus * † Bitter fleabane SH G5T5 PE
Erigeron hyssopifolius Hyssop-leaved fleabane S2 G5 SC
Eriocaulon parkeri Parker's pipewort S3 G3 SC
Eupatorium pubescens Hairy boneset S1 G5T5 E
Eupatorium sessilifolium Upland boneset S1 G5 E
Euphrasia oakesii * Oakes' eyebright SH G4 PE
Eurybia schreberi * † Schreber's wood-aster SX G4 PE
Euthamia caroliniana Narrow-leaved goldenrod S2 G5 T
Eutrochium fistulosum Hollow joe-pye weed S2 G5? SC
Festuca prolifera Arctic red fescue S1 GU E
Fimbristylis autumnalis Fall fimbry S2S3 G5 SC
Galearis spectabilis Showy orchis S1 G5 E
Galium brevipes Limestone swamp bedstraw SH G4? PE
Galium kamtschaticum Boreal bedstraw S2 G5 SC
Galium labradoricum Bog bedstraw S2 G5 SC
Galium obtusum * Blunt-leaved bedstraw SX G5 PE
Gamochaeta purpurea * Purple cudweed SX G5 PE
Gentiana rubricaulis Red-stemmed gentian S1 G4? T
Gentianella amarella ssp. acuta Northern gentian S1 G5T5 E
Gentianella quinquefolia * Stiff gentian SH G5 PE
Geocaulon lividum Northern comandra S3 G5 SC
Geum fragarioides Barren-strawberry S1 G5 E
Glyceria acutiflora Sharp-scaled mannagrass S1 G5 E
Goodyera oblongifolia Giant rattlesnake-plantain S1 G5? E
Hackelia deflexa ssp. americana Northern stickseed S1 G5T5 E
Harrimanella hypnoides Moss bell-heather S1 G5 T
Hedysarum alpinum ssp. americanum Alpine sweet-broom S3 G5T5? SC
Heterantha dubia Water stargrass S3 G5 SC
Hieracium gronovii * Hairy hawkweed SX G5 PE
Hieracium robinsonii Robinson's hawkweed S1 G2G3 E
Hieracium venosum Rattlesnake hawkweed S1 G5T4Q E
Hottonia inflata Featherfoil S1 G4 T
Houstonia longifolia Long-leaved bluet S2S3 G4G5TNR SC
Huperzia apressa Mountain firmoss S2 G4G5 SC
Huperzia selago Northern firmoss S2 G5 T
Hypericum ascyron Great St. John's-wort S1 G4 E
Hypoxis hirsuta * Yellow star-grass SX G5 PE
Ilex glabra Ink-berry S1 G5 E
Ilex laevigata Smooth winterberry holly S3 G5 SC
Impatiens pallida Pale jewel-weed S2 G5 SC
Iris prismatica Slender blue flag S2 G4G5 T
Isoetes acadiensis Acadian quillwort S2 G3Q SC
Isoetes prototypus Prototype quillwort S1 G2G3 T
Isoetes riparia var. canadensis * † Shore quillwort SH G5? PE
Isotria medeoloides Small whorled pogonia S2 G2 E
Isotria verticillata * Large whorled pogonia SX G5 PE
Iva frutescens ssp. oraria Marsh-elder S1 G5T5 E
Juncus alpinoarticulatus ssp. americanus Alpine rush S3 G5T5? SC
Juncus secundus Secund rush S1 G5? T
Juncus stygius ssp. americanus Moor rush S2 G5T5 SC
Juncus subtilis Slender rush S1 G4 E
Juncus torreyi * Torrey's rush SH G5 PE
Juncus vaseyi Vasey's rush S1 G5? E
Kalmia latifolia Mountain-laurel S2 G5 SC
Kalmia procumbens Alpine-azalea S1 G5 T
Krigia virginica Dwarf dandelion S1 G5 E
Lechea tenuifolia * Slender pinweed SX G5 PE
Lespedeza hirta Hairy bush-clover S1 G5T5? E
Liatris novae-angliae Northern blazing star S1 G5?T3 T
Lilaeopsis chinensis Lilaeopsis S2 G5 SC
Limosella australis Mudwort S3 G4G5 SC
Lindera benzoin Spicebush S3 G5 SC
Lindernia dubia var. anagallidea * Slender false pimpernel SH G5T4 PE
Lipocarpha micrantha Dwarf bulrush S1 G5 T
Lobelia siphilitica * Great blue lobelia SX G5 PE
Lomatogonium rotatum Marsh felwort S1 G5 T
Lonicera dioica Mountain honeysuckle S2 G5 E
Lonicera oblongifolia Swamp honeysuckle S3 G4 SC
Lupinus perennis * † Wild lupine SX G5T4? PE
Luzula confusa Northern wood rush S1 G5 E
Luzula spicata Spiked wood rush S1 G5 T
Lycopodiella alopecuroides Foxtail bog-clubmoss S1 G5 E
Malaxis monophyllos ssp. brachypoda White adder's-mouth S1 G5 E
Micranthes foliolosa Star saxifrage S1 G4 E
Mikania scandens * Climbing hempweed SH G5 PE
Minuartia glabra Smooth sandwort S3 G4 SC
Minuartia groenlandica Mountain sandwort S3 G5 SC
Minuartia michauxii Michaux's sandwort S1 G5 E
Minuartia rubella Arctic sandwort S1 G5 E
Montia fontana Blinks S2 G5 SC
Muhlenbergia richardsonis Soft-leaf muhly S3 G5 SC
Muhlenbergia sobolifera Cliff muhly SH G5 E
Nabalus boottii Boott's rattlesnake root S1 G2 E
Nabalus racemosus Glaucous rattlesnake root S3 G5 SC
Neottia auriculata Auricled twayblade S2 G3G4 T
Nuphar advena Yellow pond-lily S2 G5T5 SC
Nymphaea leibergii Pygmy water-lily S1S2 G5 T
Oenothera nutans * Riverbank evening primrose SH G4 PE
Omalotheca supina Alpine cudweed S1 G5 E
Ophioglossum pusillum Northern adder's-tongue fern S1 G5 SC
Osmorhiza depauperata* Blunt-fruited sweet-cicely SH G5 PE
Oxytropis campestris var. johannensis St. John oxytrope S1 G5T4 T
Panax quinquefolius American ginseng S3 G3G4 E
Parietaria pensylvanica * Pennsylvania pellitory SX G5 PE
Paronychia argyrocoma Silverling S1 G4 T
Pedicularis furbishiae Furbish's lousewort S2 G2 E
Persicaria robustior * Stout smartweed SH G4G5 PE
Phegopteris hexagonoptera Broad beech fern S2 G5 SC
Phleum alpinum Mountain timothy S2 G5 T
Phryma leptostachya * Lopseed SH G5 PE
Phyllodoce caerulea Mountain heath S1 G5 T
Pinguicula vulgaris Common butterwort S1 G5 E
Piptatherum canadense Canada mountain-ricegrass S2 G5 SC
Platanthera flava var. herbiola Pale green orchis S2 G4T4Q SC
Platanthera leucophaea Prairie white-fringed orchid S1 G3 E
Platanus occidentalis * Sycamore SX G5 PE
Poa glauca White bluegrass S1 G5 T
Poa laxa ssp. fernaldiana Wavy bluegrass S1 G3 E
Polemonium vanbruntiae Bog Jacob's-ladder S1 G3G4 E
Polygala cruciata ssp. aquilonia * † Marsh milkwort SH G5T4 PE
Polygala senega Seneca snakeroot S1 G4G5 E
Polygonum douglasii Douglas' knotweed S2 G5 SC
Polygonum tenue * Slender knotweed SH G5 PE
Potamogeton friesii Fries' pondweed S1 G4 E
Potamogeton pulcher Spotted pondweed S1 G5 T
Potamogeton strictifolius Straight-leaved pondweed S1 G5 T
Potamogeton vaseyi Vasey's pondweed S2 G4 SC
Primula laurentiana Bird's-eye primrose S2 G5 SC
Primula mistassinica Mistassini primrose S3 G5 SC
Proserpinaca pectinata Comb-leaved mermaid-weed S1 G5 E
Prunus maritima Beach plum S1 G4 E
Pseudognaphalium micradenium * † Small rabbit-tobacco SH G4G5T3? PE
Pycnanthemum muticum * Blunt mountain-mint SH G5 PE
Pyrola minor Lesser wintergreen S2 G5 SC
Quercus bicolor Swamp white oak S1 G5 T
Quercus coccinea Scarlet oak S1 G5 E
Quercus montana Chestnut oak S1 G5 T
Ranunculus ambigens * Water-plantain spearwort SH G4 PE
Ranunculus fascicularis Early crowfoot S1 G5 T
Ranunculus gmelinii Small yellow water crowfoot S2 G5T5 SC
Rhododendron lapponicum Lapland rosebay S1 G5 T
Rhododendron maximum Great rhododendron S1 G5 T
Rhododendron viscosum Clammy azalea S1 G5 E
Rhynchospora capillacea Horned beak-rush S1 G4 T
Rhynchospora macrostachya Tall beak-rush S1 G4 E
Rosa acicularis ssp. sayi * Prickly rose SH G5T5 PE
Sagittaria filiformis Narrow-leaved arrowhead S2 G4G5 SC
Sagittaria montevidensis ssp. spongiosa Spongy-leaved arrowhead S3 G5T4 SC
Sagittaria rigida Stiff arrowhead S2 G5 SC
Salicornia bigelovii Dwarf glasswort S1 G5 SC
Salicornia maritima * Jointed glasswort SH G5 PE
Salix arctophila Arctic willow S1 G5 E
Salix argyrocarpa * Silverleaf willow SH G4 PE
Salix candida Hoary willow S1 G5 E
Salix exigua ssp. interior Sandbar willow S1 G5 E
Salix herbacea Dwarf willow S1 G5 T
Salix myricoides Blue-leaf willow S2 G4 T
Salix occidentalis Dwarf prairie willow SU G5T5T4 SC
Salix planifolia Tea-leaved willow S1 G5 T
Salix uva-ursi Bearberry willow S1 G5 T
Samolus valerandi ssp. parviflorus Water pimpernel S3 G5T5 SC
Sanguisorba canadensis Canada burnet S1 G5 T
Sassafras albidum Sassafras S2 G5 SC
Saxifraga paniculata ssp. neogaea Alpine saxifrage S1 G5 E
Scirpus georgianus Georgia bulrush SU G5 SC
Scirpus longii Long's bulrush S2 G2G3 T
Scirpus pendulus Pendulous bulrush S2 G5 SC
Scrophularia marilandica * Carpenter's square SX G5 PE
Scutellaria parvula var. missouriensis * Leonard's skullcap SH G4T4 PE
Selaginella apoda Creeping spike-moss S2 G5 E
Selaginella selaginoides Low spike-moss S1 G5 T
Sericocarpus asteroides White-topped aster S1 G5 E
Shepherdia canadensis Canada buffaloberry S1 G5 E
Silene acaulis var. excapa * Moss campion SX G5T5 PE
Solidago leiocarpa Cutler's goldenrod S1 G5T4 T
Solidago speciosa Showy goldenrod S1 G5 T
Sorghastrum nutans Indian grass S1 G5 E
Sphenopholis obtusata * Prairie wedge-grass SH G5 PE
Spiranthes lacera var. gracilis * Southern Slender Ladies'-tresses SH G5T4T5 PE
Spiranthes lucida Shining ladies'-tresses S1 G5 T
Sporobolus compositus var. drummondii Tall dropseed S1 G5TNR E
Stuckenia filiformis Thread-leaved false pondweed S2 G5T5 SC
Suaeda calceoliformis American sea-blite S2 G5 T
Symphyotrichum anticostense Anticosti aster S1 G3 E
Symphyotrichum dumosum * Bushy aster SH G5T3T5 PE
Symphyotrichum patens * Late purple aster SX G5 PE
Symphyotrichum subulatum Small salt-marsh aster S1 G5 T
Tanacetum bipinnatum ssp. huronense Huron tansy S2S3 G5T4T5 SC
Thalictrum thalictroides Rue-anemone S1 G5 E
Thalictrum venulosum var. confine Boundary meadow-rue S1 G5 T
Trichophorum clintonii Clinton's bulrush S3 G4 SC
Triglochin gaspensis Gaspé arrow-grass S2 G3G4 SC
Trillium grandiflorum * Large white trillium SH G5 PE
Triosteum aurantiacum Wild coffee S1 G5 E
Triphora trianthophora Nodding pogonia S2 G3G4 T
Ulmus rubra * Slippery elm SH G5 PE
Vaccinium boreale Alpine blueberry S2 G4 SC
Vahlodea atropurpurea Mountain hairgrass S1 G5 E
Valeriana uliginosa Marsh valerian S2 G4Q SC
Verbena urticifolia White vervain S1? G5 SC
Veronica wormskjoldii Alpine speedwell S1 G4G5 E
Viola canadensis Tall white violet SH G5 PE
Viola novae-angliae New England violet S2 G4Q SC
Viola palmata * Palmate-leaved violet SH G5 PE
Vitis aestivalis var. bicolor Summer grape S2 G5T5 T
Wolffia brasiliensis Pointed water-meal SU G5 SC
Wolffia columbiana Columbia water-meal S2 G5 SC
Woodsia alpina Northern woodsia S1 G4 T
Woodsia glabella Smooth woodsia S1 G5 T
Woodsia obtusa Blunt-lobed woodsia S1 G5 T
Woodwardia areolata * Netted chain fern SH G5 PE
Xyris smalliana Yellow-eyed grass S1 G5 E
Zannichellia palustris Horned pondweed S2 G5 SC