The Plant Watch List (WL) is an unofficial, non-regulatory list of plants of known or suspected conservation concern that NHESP is interested in tracking.  Species are included on the list for a number of reasons:

Wild Lupine (Lupinus perennis), Watch List.  Photo by Paul Somers
Wild Lupine, Watch List. Photo by Paul Somers

  1. The species is thought to be rare, declining, or vulnerable, but there is insufficient information on the condition, number and size of populations to make a determination (termed "Uncommon" in the "Reasons" for listing field)
  2. The species was removed from the official regulatory list, but the Program believes it still is in need of some conservation attention (termed "MESA-Delisted" in the "Reasons" for listing field)  
  3. The species is uncommon and there are uncertainties about the taxonomic status (termed "Taxonomic Issues" in the "Reasons" for listing field)
  4. the species is uncommon and its status as a native or an introduced species is undecided (termed "Introduced?" in the "Reasons" for listing field)
  5. The species is recently discovered or rediscovered in the Commonwealth and is placed on the Watch List to ensure it is tracked while botanists determine whether it is appropriate for proposal to the MESA List.
Scientific NameSynonymCommon NameS RankNew England RankG RankReason
Acalypha virginica Three-seeded MercuryS1S2 G5Uncommon
Acer nigrum Acer saccharum var. nigrumBlack MapleS3 G5MESA-Delisted
Achillea millefolium var. lanulosaA. millefolium var. occidentalis; A. millefolium var. borealis; A. borealisSeaside YarrowS3S4 G5T5MESA-Delisted
Agrimonia rostellata Small-beaked AgrimonySNR G5Introduced?
Amelanchier nantucketensisA. stolonifers var. micropetalaNantucket ShadbushS31G3QMESA-Delisted
Angelica lucidaCoelopleurum lucidumSeaside-angelicaS2? G5Uncommon
Asclepias tuberosa Orange Milk-weedS4 G5?MESA-Delisted
Athyrium asplenioidesA. filix-femina var. asplenioidesSouthern Lady-fernS2?2G5T5Uncommon
Atriplex glabriuscula Prostate OracheS1S2 G4Uncommon
Betula cordifoliaB. papyrifera var. cordifoliaHeart-leaf Paper-birchSNR G5T5Uncommon
Betula nigra River BirchS3INDG5Uncommon
Bidens beckiiMegalodonta beckiiWater MarigoldS2 G4G5Uncommon
Boechera strictaArabis drummondiiDrummond's RockcressS2S3 G5Uncommon
Bolboschoenus fluviatilisScirpus fluviatilisRiver BulrushS2 G5MESA-Delisted
Bolboschoenus novae-angliaeScirpus cylindricusLong-stalked BullrushS2?2G5Uncommon
Botrychium angustisegmentumB. lanceolatum ssp. angustisegmentumNarrow Triangle Grape-fernS2S3 G5TNRUncommon
Botrychium matricariifolium Daisy-leaf MoonwortS2 G5Uncommon
Botrychium oneidense Blunt-lobed Grape-fernS1S22G4Uncommon
Botrychium simplexB. Simplex var. simplexLeast MoonwortS1S2 G5Uncommon
Botrychium tenebrosumB. simplex var. tenebrosumSwamp MoonwortS1S2INDG5T4?QUncommon
Calamagrostis canadensis var. macouniana Macoun's ReedgrassSNRINDG5T5?Uncommon
Cardamine bulbosa C. rhomboideaSpring-CressS2S3 G5Uncommon
Cardamine maximaDentaria maxima; Dentaria anomalaThree-leaved ToothwortS2?3(b)G5Uncommon
Carex abscondita Concealed SedgeS2? G4G5Uncommon
Carex aestivalis Summer-sedgeS2S3 G4Uncommon
Carex aquatilis var. substrictaC. substrictaWater-sedgeSNR G5TNRUncommon
Carex bicknellii Bicknell's SedgeS1S22G5Uncommon
Carex buxbaumii Buxbaum's SedgeS2? G5Uncommon
Carex cristatella Crested SedgeS2? G5Uncommon
Carex debilis var. debilis Southern Stalked SedgeSNR2G5T5Uncommon
Carex deflexa Mountain SedgeS1 G5Historic Rediscovered
Carex diandra Panicled SedgeS1S2 G5Uncommon
Carex emoryi Emory's SedgeS12G5Uncommon
Carex exilis Bog SedgeS2S3 G5Uncommon
Carex haydenii Hayden's SedgeS1S2 G5Uncommon
Carex limosa Mud SedgeS2? G5Uncommon
Carex molesta Troublesome SedgeS1?2G4Uncommon
Carex prairea Praire-sedgeS1? G5Uncommon
Carex retrorsa Hooked SedgeS2S3 G5Uncommon
Carex sparganioides Bur-sedgeS43(b)G5Uncommon?
Carex viridula ssp. viridula Little Green SedgeS1S2 G5T5Uncommon
Caulophyllum giganteumC. thalictroides var. giganteumEarly Blue CohoshS2S3 G4G5QUncommon
Chenopodium simplexC. gigantospermum; Chenopodiumhybridum var. gigantospermumMaple-lead GoosefootS3? G5Uncommon
Chenopodium standleyanumC. hybridum var. standleyanumWoodland-goosefootSNR G5Introduced?
Cirsium horridulum var. horridulum Yellow ThistleS2S32(a)G5T5Uncommon
Coeloglossum virideC. viride var. virescens; Habenaria viridis var. bracteataFrog-orchisS3 G5 
Corema conradii Broom CrowberryS3 G4MESA-Delisted
Coreopsis rosea Pink TickseedS31G3Uncommon
Crataegus keepiiC. brunetiana, C. searsiiKeep's HawthornSNR GNRUncommon?
Cuscuta coryli Pondshore-dodderS1?2G5?Uncommon
Cuscuta polygonorum Smartweed-dodderS3S42G5Introduced?
Cyperus odoratusC. ferruginescensSaltmarsh FlatsedgeS1S2 G5MESA-Delisted
Cyperus polystachyosC. polystachyos var. texensisTexas FlatsedgeS2S3 G5Uncommon
Cyperus retrorsus Pine Barren FlatsedgeS1?2GNRUncommon
Cypripedium parvifloum var. pubescensC. calceolus var. pubescensWoodland Yellow Lady's-slipperS1? G5T5Uncommon
Cystopteris laurentiana Laurentian Bladder FernS2S31G3Uncommon
Desmodium canescens Hoary Tick-trefoilS3 G5Uncommon
Dichanthelium acuminatum ssp. acuminatumD. acuminatum var. acuminatum; Panicum auburneAuburn Panic-grassS1?INDG5T5Uncommon
Digitaria cognata ssp. cognataLeptoloma cognatumFall Witch-grassSNR G5T5Introduced?
Dioscorea villosa Wild YamSNR G4G5Introduced?
Diplazium pycnocarponAthyrium pycnocarponGlade FernS3 G5MESA-Delisted
Dryopteris campylopteraD. spinulosa var. americanaMountain Wood-fernS3? G5Uncommon
Dryopteris goldiana Goldie's FernS3 G4MESA-Delisted
Elatine triandra European WaterwortSNR G5Introduced?
Eleocharis engelmannii var. detonsa Englemann's Spike-rushS1S2 G4G5TNRUncommon
Eleocharis engelmannii var. engelmannii Englemann's Spike-rushS1S2 G4G5TNRUncommon
Eleocharis erythropodaE. calvaRedfoot Spike-rushS3 G5MESA-Delisted
Eleocharis melanocarpa Black-fruited Spike-rushS3 G4MESA-Delisted
Eleocharis rostellata Beaked or Saltmarsh SedgeS2?2G5Uncommon
Elymus macgregorii  Early Wild RyeS2?2GNRUncommon
Elymus trachycaulus ssp. trachycaulusAgropyron trachycaulum var. novae-angliaeSlender Wild RyeSNR G5T5Uncommon
Equisetum pratense Meadow-horsetailS2 G5Uncommon
Equisetum variegatum ssp. variegatum Variegated Scouring RushS3 G5T5MESA-Delisted
Eragrostis capillaris Lace-grassS2? G5Uncommon
Erechtites hieraciifolius var. megalocarpusE. megalocarpusSeaside PilewortS2S3 G5T3Uncommon
Euphorbia nutansChamaesyce nutansEyebane BroomspurgeSNRINDG5 
Eurybia radulaAster radulaRough AsterS1S2 G5Uncommon
Fuirena pumila Annual Umbrella-sedgeS33(b)G4MESA-Delisted
Galearis spectabilisOrchis spectabilisShowy OrchisS2S33(b)G5Uncommon
Gentiana linearis Narrow-leaved GentianS2? G4G5Uncommon
Gentianella quinquefoliaG. quinquefolia ssp. quinquefoliaStiff GentianS2S3 G5Uncommon
Geranium bicknellii Bicknell's Crane's BillS2S3 G5Uncommon
Genum virginianum Virginia AvensS2? G5Uncommon
Hedeoma hispida Rough PennyroyalS1 G5Introduced?
Helenium autumnaleH. tenufoliumCommon SneezeweedS3? G5Uncommon
Heteranthera dubiaZosterella dubiaWater Star-grassS2S33(b)G5Uncommon
Hottonia inflata FeatherfoilS3 G4Uncommon
Hypopitys lanuginosaMonotropa lanuginosaHairy Pine-sapSNRINDGNRUncommon?
Isotria verticillata Large Whorled PogoniaS3S4 G5MESA-Delisted
Juglans cinerea ButternutS4? G4Uncommon
Juncus ambiguusJ. bufonius var. halophilusSeaside Toad-rushS1? G5Historic Rediscovered
Juncus biflorus Two-flowered RushSNR2G5Taxonomix Issue
Juncus bodosus Knotted RushSNR G5Uncommon
Juncus torreyi Torrey's RushSNR2G5Introduced?
Juniperus horizontalis Prostate JuniperSNR3(b)G5Introduced?
Lactuca hirsutaL. hirsuta var. sanguineaHairy Wild LettuceS2S3INDG5?Uncommon
Lathyrus palustrisL. palustris var. myrtifolius; L. palustris var. pilosusVetchling Marsh-peaSNR G5Uncommon
Lechea minor Thyme-leaf PinweedS2S3INDG5Uncommon
Lespedeza angustifolia  Narrow-leaved Bush-cloverS3? G5Uncommon
Lespedeza frutescensL. violaceaViolet Bush-cloverS3 G5MESA-Delisted
Lespedeza stuevei Stueve's Bush-cloverSNRINDG4? 
Lilaeopsis chinensis LilaeopsisS2? G5Uncommon
Linnaea borealis ssp. americana TwinflowerS3 G5T5Uncommon
Linum striatumL. striatum var. multijugumPanicled Yellow Flax, Ridgestem Yellow FlaxS2S3 G5Uncommon
Listera australisNeottia australisSouthern TwaybladeS12GNRUncommon
Lobelia kalmii Brook-lobeliaS2S3 G5Uncommon
Lonicera sempervirens Trumpet HoneysuckleSNR2G5Introduced?
Lupinus perennis Wild LupineS3S43(a)G5Uncommon
Luzula bulbosa Bulbous Wood-rushS2? G5Uncommon
Luzula multiflora ssp. frigidaL. multiflora var. fusconigraBoreal Wood-rushSNR G5T5Uncommon
Lycopus amplectens Sessile Water-horehoundS2S3 G5Uncommon
Lythrum alatum Winged LoosestrifeS1?2G5Uncommon
Maianthemum trifolium Three-leaved Solomon's SealS3? G5Uncommon
Malaxis unifolia Green Adder's MouthS2? G5Uncommon
Menispermum canadense MoonseedS3 G5Uncommon
Moneses uniflora One-flowered PyrolaS2S3 G5Uncommon
Myriophyllum sibiricumM. exalbescensNorthern Water-milfoilS1S2 G5Uncommon
Nabalus albusPrenanthes albaWhite LettuceSNR G5Uncommon
Parietaria pensylvanica Rock-pellitoryS2S3 G5Uncommon
Paronychia fastigiata var. fastigiata Hairy Forked ChickweedSNR2G5T5Introduced?
Paspalum setaceum var. psammophilumP. psammophilumSand Bead-grassS2S32G5T4?Uncommon
Paspalum setaceum var. setaceum Small Fruited Bead-grass or Slender Bead-grassS3? G5T5Uncommon
Pellaea atropurpurea Purple Cliff-brakeS3 G5MESA-Delisted
Phragmites australis ssp. americanus Phragmites, North American ReedS3INDG5T4Uncommon
Pinus resinosa Red PineS2S3 G5Uncommon
Piptochaetium avenaceum Stipa avenaceaBlack OatgrassSNR G5Uncommon
Plantago pusilla Dwarf PlantainS1? G5Introduced?
Platanthera hookeriHabenaria hookeriHooker's OrchisS2? G4Uncommon
Platanthera huronensisP. hyperborea var. huronensis; Habenaria huronensisNorthern Green OrchisS2?INDG5T5?Uncommon
Platanthera macrophyllaP. orbiculata var. macrophylla; Habenaria macrophyllaLarge Round-leaved OrchisS2? G5T4Uncommon
Platanthera orbiculataHabenaria orbiculataRound-leaved Orchis or OrchidS1S2 G5Uncommon
Podophyllum peltatum May-appleSNR2G5Introduced?
Podostemum ceratophyllum ThreadfootS2 G5MESA-Delisted
Polygala nuttallii Nuttall's MilkwortS3 G5MESA-Delisted
Polygala verticillataP. verticillata var. isocyclaWhorled MilkwortS2S3 G5Uncommon
Polygonum tenue Rock KnotweedS2S3 G5Uncommon
Populus balsamifera ssp. balsamifera Balsam-poplarS2S3 G5T5Uncommon
Potamogeton gemmiparusP. pusillus var. gemmiparusTiny PondweedS2?1G5T3Uncommon?
Potamogeton obtusifolius Blunt-leaved PondweedS1? G5Uncommon
Pseudognaphalium macouniiGnaphalium viscosum; Gnaphalium macouniiClammy EverlastingS1S2 G5Uncommon
Pteridium aquilinum ssp. pseudocaudatum Pine Barrens BrakenSNR G5T5Uncommon
Quercus stellata Post OakS3S4 G5MESA-Delisted
Ranunculus allegheniensis Allegheny ButtercupS2? G4G5Uncommon
Ranunculus fascicularis Early ButtercupS2? G5Uncommon
Rhododendron periclymenoidesR. nudiflorumPinxter-flowerS2? G5Uncommon
Ribes americanum Wild Black CurrantS3S4 G5MESA-Delisted
Ribes rotundifolium Round-leaved GooseberryS1?2G5Uncommon
Ribes triste Swamp Red CurrantS3 G5MESA-Delisted
Rosa blanda Smooth RoseS2S3 G5Uncommon
Rubus cuneifoliusR. chapmaniiSand-blackberryS1S22G5Uncommon
Rumex hastatulus Dune-sorrelSNR G5Introduced?
Sagina decumbens ssp. decumbens  Trailing PearlwortSNRINDG5T5Introduced?
Sagina nodosa ssp. nodosa Knotted PearlwortSU2G5T5?Introduced?
Sagittaria rigida Mud ArrowheadS2? G5Uncommon
Salix candida Hoary WillowS33(b)G5MESA-Delisted
Salix pedicellarisS. pedicellaris var. hypoglauca; S. pedicellaris var. tenuescensBog WillowS2? G5Uncommon
Salix serissima Autumn WillowS3 G4MESA-Delisted
Sanicula trifoliata Trefoil SanicleS2S3 G4Uncommon
Schoenoplectus acutus var. acutusScirpus acutusHard-stemmed BulrushS2S3 G5T5Uncommon
Schoenoplectus torreyiScirpus torreyiTorrey's BulrushS2? G5?Uncommon
Scirpus pendulusS. lineatusPendulous BulrishS3 G5MESA-Delisted
Scirpus polyphyllus Appalacian BulrushS2? G5Uncommon
Scleria reticularis Pondshore Nut-sedgeS3 G4MESA-Delisted
Scutellaria parvula var. missouriensisS. parvula var. leonardii; S. ambiguaSmall SkullcapSNRINDG4T4Introduced?
Sedum ternatum Mountain-stonecropSNR G5Introduced?
Selaginella rupestris Rock SpikemossS3S4 G5MESA-Delisted
Silene caroliniana ssp. pensylvanica Wild PinkS2S3 G5T4T5Uncommon
Solidago speciosa var. speciosa Showy GoldenrodS2S3 G5T5?Uncommon
Sparganium androcladum Shining Bur-reedS3?INDG4G5Uncommon
Sparganium angustifoliumS. emersum var. angustifolium; S. emersum var. multipedunculatum; S. multipedunculatumNarrow-leaved Bull-reedS2S3 G5Uncommon
Sparganium fluctuans Floating Bull-reedS2S3 G5Uncommon
Spiranthes lucida  Shining or Wide-leaved Ladies'-tressesS2? G5Uncommon
Spiranthes tuberosaS. tuberosa var. grayiLittle Ladies'-tressesS3S4 G5MESA-Delisted
Sporobolus compositus var. compositusS. asperTall DropseedSNR G5T5Introduced?
Sporobolus cryptandrus Sand DropseedS2? G5Uncommon
 Stachys hyssopifolia Hyssop Hedge-nettleS3S43(b)G4G5MESA-Delisted
Stellaria borealis ssp. borealisS. calycantha; S. calycantha var. floribunda; S. calycantha var. isophyllaNorthern StarwortS2S3 G5T5Uncommon
Streptopus amplexifolius Clasping-leaf Twisted-stalkS3? G5MESA-Delisted
Suaeda maritima ssp. richiiS. richiiRich's Sea-bliteS2S31G5T3MESA-Delisted
Utricularia minor Lesser BladderwortS2S3 G5Uncommon
Uvularia grandiflora Large-flowered BellwortS3 G5MESA-Delisted
Verbesina alternifolia WingstemSNR G5Introduced?
Veronica serpyllifolia ssp. humifusaVeronica tenellaNorthern Thyme-leaf SpeedwellSNR G5T5?Introduced?
Viola renifolia V. renifolia var. brainerdiiKidney-leaf VioletS1S2 G5Uncommon
Viola rostrata Long-spurred VioletS2S3 G5Uncommon
Viola selkirkii Great-spurred VioletS1S2 G5?Uncommon
Viola subsinuataV. palmataEarly Blue VioletS1S2 G3G5Uncommon
Wolffia borealisW. punctataNorthern Water-mealSNR G5Uncommon
Wolffiella gladiataW. floridanaSickle Water-mealSNRINDG5Uncommon
Xyris montana Northern Yellow-eyed GrassS2? G4Uncommon
Xyris smallianaX. congdoniiQuagmire Yellow-eyed grassS43(b)G5Uncommon?
Zizania palustris var. palustrisZ. aquatica var. angustifoliaSlender Wild RiceS1S2 G4G5T4T5Uncommon

The conservation status of a species is designated by a number (1-5) and preceded by a letter reflecting the appropriate geographic scale of the assessment.  S Rank refers to "subnational" or the local/state status, while G Rank refers to the "global" status (looking at the species as a whole). Please see "Plant Conservation Status " for additional information on specific rankings.