Scleria pauciflora var. caroliniana — papillose nutsedge

Endangered — New for Plymouth County — Plymouth (a few scattered plants or colonies within ca. 400-acre area)

Oxalis violacea — violet woodsorrel

Endangered — Dartmouth (unless deliberately introduced, this is a new location. According to NHESP website, last observed in Bristol Co., Easton in 1889).

Rhynchospora torreyana — Torrey's beaksedge

Endangered — Plymouth (a previously known location)

Symphyotrichum tradescantii (Aster tradescantii) — Tradescant's aster

Threatened — New for Plymouth County — Carver. Found in 2009. Sample checked by Arieh Tal

Carex typhina — cat-tail sedge

Threatened — Taunton. Found in 2009, perhaps a known location.

Rhynchospora inundata — inundated horn-sedge

Threatened — Carver (a previously known location)

Linum intercursum — sandplain flax

Special Concern — Plymouth. At least two subpopulations within ca. 4,000-acre bounding box. Had not been recorded in the area since 1928.

Carex haydenii — Hayden's sedge

Watch-Listed — Milton (Blue Hills Res., Neponset R. floodplain)

Cirsium horridulum — yellow thistle

Watch-Listed — Mattapoisett

Geum virginianum — cream-colored avens

Watch-Listed — Concord

Lespedeza angustifolia — narrow-leaved bush-clover

Watch-Listed — Plymouth (Myles Standish State Forest), Falmouth

Bolboschoenus fluviatilis (Scirpus fluviatilis) — river bulrush

Watch-Listed — Boxford, 2008

Selaginella rupestris — rock spikemoss

Watch-Listed — Needham (a previously known location)

New for Massachusetts — Wachusett Reservoir, Boylston, 2008-2009

Albizzia julibrissin — silk tree

New for Massachusetts — introduced — Fall River. At access road to a wildlife management area, on a trash pile with other introduced plants.

Briza maxima — big quaking grass

New for Massachusetts — introduced — Blue Hills Res., Quincy. Introduced during recultivation of the Blue Hills Reservoir, naturalized.

Hedera hibernica — Atlantic ivy

New for Massachusetts — introduced — Boston. Discovered by Hugh McAllister in 2012, publication pending.

Quercus marilandica — barren oak

New for Massachusetts — introduced — Tidmarsh Farms, Plymouth. Needs confirmation.

Rubus caesius — European forest blackberry

New for Massachusetts — introduced — Muddy River, Brookline. A large naturalized population.

New for Massachusetts — introduced — Pittsfield, 2011-2012.

Styphnolobium japonicum (Sophora japonica) — Japanese pagoda-tree

New for Massachusetts — introduced — Blue Hills Res., Quincy 2002. Must have been introduced during recultivation of Quincy Quarries.

New for Massachusets — Cambridge, 2012. Collected and identified by Hugh McAllister.

Elodea canadensis — northern waterweed

New for Plymouth County — Carver, Plymouth

Ludwigia alternifolia — seedbox, squarepod

New for Plymouth County — Mattapoisett (might have been accidentally introduced with a seed mix)

Lycopodiella appressa x inundata — hybrid bog clubmoss

New for Plymouth County — Carver; Rochester, 2008.

Eupatorium maculatum — spotted Joe-Pye-weed

New for Plymouth County — introduced — Mattapoisett. Might have been deliberately introduced with a seed mix, now naturalized.

Geum urbanum — city avens

New for Plymouth County — introduced — Plymouth (population along road to Plimoth Plantation); Concord.

Gypsophila elegans — Caucasus gypsophila

New for Plymouth County — introduced — Plymouth (Plymouth Long Beach, waif, a small clump found together with Vaccaria hispanica.)

Lysimachia clethroides — gooseneck loosestrife

New for Plymouth County — introduced — Plymouth (a solitary waif on the shore of Savery Pond)

Panicum amarum ssp. amarulum — bitter panic grass

New for Plymouth County — introduced — Mattapoisett. In Massachusetts it has been known from Barnstable County.

Pascopyrum smithii — western wheatgrass

New for Plymouth County — introduced — Plymouth, 2012. Has been known only from western Massachusetts. Needs confirmation. XXX

Rosa luciae — memorial rose

New for Plymouth County — introduced — Plymouth (Myles Standish State Forest, population area estimate: 150 sq. meters)

Sisymbrium loeselii — small tumbleweed mustard

New for Plymouth County — introduced — Plymouth, 2012

Digitaria violascens — violet crabgrass

New for Norfolk, Plymouth County — introduced — Needs confirmation XXX:: A new county record or mis-ID? Reported only from two western MA counties [FR WO]. Braintree 2011, Plymouth 2010

Centaurium pulchellum — branching centaury

New for Norfolk County — introduced — Milton (Blue Hills Res., Burma Rd.), 2012. Sample was not preserved. Plant could not be relocated due to mowing.

Rhus aromatica — fragrant sumac

New for Norfolk County — introduced — Milton (Blue Hills Res.). Introduced during recultivation of the Blue Hills Reservoir; naturalized.

Carex trisperma — three-seeded sedge

New for Essex County — Boxford, 2009. This sedge is sometimes united with C. billingsii but differs in wider leaves; also occupying different habitats (shaded swamps) away from the coastal area. C. trisperma has been recorded only from western countes: BE FR HS WO.

New for Barnstable County — Formerly identified as Elytrigia pungens. Identification to be confirmed.

Hieracium flagellare — whip hawkweed

New for Barnstable County — introduced — Falmouth (discovered by Arieh Tal); New Bedford (to be confirmed: identified from photo contributed by Fran LeCuyer)

Neslia paniculata — ball mustard

New for Barnstable County — introduced — Falmouth, 2012. To be re-located.

Aletris farinosa — colic-root

Mattapoisett

Alisma subcordatum — lesser water-plantain, southern water-plantain

Boston, 2005 (Stony Brook Res.). Photos formerly identified as Alisma plantago-aquatica.

Alisma triviale — larger water-plantain, northern water-plantain

New Bedford, Dedham, Sturbridge, Canton. Photos formerly identified as Alisma plantago-aquatica.

Bidens vulgata — tall beggar-ticks

Boston (Arnold Arboretum)

Carex arctata — northern wood sedge

Boxford, 2009

Carex argyrantha — silvery sedge

Boxford, 2009

Carex billingsii — three-seeded bog sedge

Canton (Blue Hills Res., Ponkapoag Bog)

Carex blanda — woodland sedge

Concord

Carex bullata — button sedge

Plymouth, Carver

Carex canescens ssp. disjuncta — silvery bog sedge

Canton, 2007

Carex cumulata — crowded sedge

Middleborough. Identification to be confirmed

Carex debilis var. rudgei — northern stalked sedge

Mattapoisett; Boston, 2009, Boxford, 2009

Carex deweyana — round-fruited short-scaled sedge

Boxford, 2009

Carex gynandra — northern awned sedge

Plymouth

Carex lacustris — marsh sedge, lakeside sedge

Milton, 2009

Carex lasiocarpa var. americana — slender woolly-fruited sedge

Bedford, Milton, Plymouth.

Carex leptalea — delicate sedge

Bedford, 2009

Carex longii — Long's sedge

Plymouth, Carver. Identification to be confirmed

Carex lucorum — long-beaked Pennsylvania sedge

Plymouth (Myles Standish State Forest)

Carex paleacea — saltmarsh sedge

Newbury, 2004

Carex silicea — sea-beach sedge

Brewster, 2008

Carex torta — riverside sedge

Sheffield, 2012

Carex tribuloides — blunt broom sedge

Needham, Bedford

Carex virescens — ribbed sedge

Randolph (Blue Hills Res.), Dedham

Cerastium arvense — field chickweed

Plymouth, 2012

Ceratophyllum demersum — hornwort, coontail

Plymouth

Ceratophyllum echinatum — forked coontail

Weymouth, 2009

Cystopteris tenuis — MacKay's fragile fern or brittle fern

Hadley, 2009; Milton, 2005

Dichanthelium latifolium — broad-leaved panic-grass

Medford, 2011. Formerly identified as D. commutatum.

Eleocharis elliptica — orange-fruited spike-rush

Dartmouth

Eleocharis parvula — dwarf spike-rush

Falmouth

Hierochloe odorata — Indian sweetgrass

Dartmouth, Mattapoisett

Isoetes sp. — quillwort

Plymouth (Myles Standish State Forest, Charge Pond). Floating on the surface, no macrospores, hardly possible to identify to species.

Lycopodiella appressa — southern bog clubmoss

Carver, Plymouth; Rochester, 2008

Muhlenbergia schreberi — nimblewill

Plymouth, 2012 (Morton Park)

Orobanche uniflora — one-flowered cancer-root

Milton (Blue Hills Res., Burma Rd.)

Oryzopsis asperifolia — spreading ricegrass

Quincy (Blue Hills Res.). Discovered and identified by Tom Palmer.

Oxalis dillenii — showy yellow woodsorrel

Boston (Arnold Arboretum), Plymouth.

Poa palustris — fowl-meadow grass

Milton, Canton (Blue Hills Res.)

Puccinellia maritima — seaside alkali-grass

Dartmouth

Ruppia maritima — ditch-grass, widgeon-grass

Falmouth

Scirpus atrocinctus — black-girdled woolsedge, dusky woolgrass

Boxford, 2009

Scirpus expansus — spreading bulrush

Dedham

Sibbaldiopsis tridentata — three-toothed cinquefoil

Plymouth (Myles Standish State Forest)

Sisyrinchium montanum var. crebrum — meadow blue-eyed grass

Falmouth, 2012; Plymouth

Sorghastrum nutans — Indian grass

Quincy, Canton, Plymouth. Appears to be re-introduced with sowing mixes.

Sporobolus vaginiflorus — poverty grass

Plymouth, 2007 (Myles Standish State Forest)

Torreyochloa pallida var. fernaldii — slender mannagrass

Plymouth (Myles Standish State Forest, Tidmarsh Farms)

Utricularia geminiscapa — twin-scaped bladderwort

Canton, 2004 (Blue Hills Res., Ponkapoag Pond)

Vulpia octoflora var. tenella — six-weeks fescue

Wareham, 2011

Wisteria floribunda — Japanese wisteria

Hingham (Wompatuck State Park)

Rubus phoenicolasius — wine raspberry

invasive — Dartmouth

Euphorbia esula — wolf's milk

invasive — Quincy

Glaucium flavum — yellow hornpoppy

invasive — Dartmouth. Photo contributed by Fran LeCuyer.

Myriophyllum spicatum — Eurasian watermilfoil

invasive — Randolph (Blue Hills Res., Ponkapoag Pond)

Aethusa cynapium — fool's parsley

introduced — Medford, 2007; Concord

Aira praecox — strict hairgrass

introduced — Dartmouth

Arrhenatherum elatius — tall oatgrass

introduced — Quincy

Avena sativa — oats

introduced — Plymouth, 2012

Betula pendula — silver birch

introduced — Cambridge, 2012. A deliberate introduction (either planted or naturalized). Collected and identified by Hugh McAllister

Cercidiphyllum japonicum — katsura tree

introduced — Medford, 2011 (Middlesex Fells Res., Lawrence Woods, seedling discovered during NEWFS field trip). Previously reported from two western counties.

Colutea arborescens — bladder senna

introduced — Quincy, 2002 (Blue Hills Res., Quincy Quarries). Must be a deliberate introduction (either planted or naturalized). If naturalized, it would be a new county record.

Eleutherococcus pentaphyllus — five-leaved aralia

introduced — Milton, 2012 (Blue Hills Res. border). A deliberate introduction (either planted or naturalized). (If naturalized, it would be a new county record.)

Eragrostis curvula — weeping lovegrass

introduced — Bourne (Carter Beal Conservation Area)

Eragrostis minor — little lovegrass

introduced — Plymouth, 2012

Gleditsia triacanthos — honey-locust

introduced — Concord

Iris sibirica — Siberian iris

introduced — Boston (Muddy R., could be planted)

Liquidambar styraciflua — sweetgum

introduced — Mattapoisett (Nasketucket Bay State Res.). About a dozen trees--a few planted at entrance and a few found in the woods. Perhaps all planted. Belmont (Beaver Brook Res., planted). Not on MA checklist.

Lolium perenne — perennial rye grass

introduced — Boston, Weymouth

Melilotus officinalis — yellow sweetclover

introduced — Quincy

Phaseolus vulgaris — green bean

introduced — Boston, 2005 (Stony Brook Res.)

Poa chapmaniana — Chapman's bluegrass

introduced — Boston (Arnold Arboretum nursery)

Poa nemoralis — woodland bluegrass

introduced — Canton (Blue Hills Res.). Sample ID by Tom Palmer.

Poa trivialis — rough bluegrass

introduced — Canton (Blue Hills Res.). Sample ID by Tom Palmer.

Rhinanthus minor — yellow rattle

introduced — Dartmouth

Sisymbrium officinale — hedge mustard

introduced — Dartmouth

Thinopyrum pycnanthum (Elymus pungens ssp. pycnanthus) — seabeach quack-grass

introduced — Weymouth, 2008 (Webb State Park)

Tilia cordata — small-leaved linden

introduced — Plymouth (large population at Plimoth Plantation)

Ulmus procera — English elm

introduced — Hingham (could be planted)

Vaccaria hispanica — cow herb

introduced — Plymouth (Plymouth Long Beach, waif, a small clump found together with Gypsophila elegans.)

Salix interior — sandbar willow

introduced — Plymouth (planted at the site of former Eel River Dam)

Calamagrostis pickeringii — Pickering's reedgrass
Endangered — In 2013 we documented a few three and three more locations for Calamagrostis pickeringii in addition to those found in 2012. For our state, this is a northern species historically known from the hills of northern (Middlesex and Essex) counties; yet all currently found subpopulations in Massachusetts are restricted to the pine barrens area in the southeast (Plymouth), apparently associated here with frost pockets and constituting parts of a single large population. We observed a few specimens in comparatively warmer and drier situations: on pocket slopes or ridges between adjacent pockets, yet invariably not far from larger (source) colonies situated around small ponds or at wet bottoms of frost pockets. In one case a subpopulation was found at a relatively dry bottom of a frost pocket.

Liatris novae-angliae — New England blazing star
Special Concern — Perhaps a new location in Plymouth

Sabatia kennedyana — Plymouth gentian
Special Concern — Perhaps a new location in Plymouth

Utricularia subulata — slender bladderwort
Special Concern — Perhaps a new location in Plymouth

Lechea minor — thyme-leaf pinweed
Watch listed — Maybe a new town record (Plymouth)

Linnaea borealis — twinflower
Watch-listed. The only image we can provide from eastern MA is that of a plant cultivated at the South Shore Natural Science Center in Norwell. We used this photo for our Plant of the Month story in May 2013 Starflower Puzzles, though have not included it in the photo gallery. The species is known to be native in 9 counties including Norfolk, Plymouth, and Barnstable, yet it is likely to be extinct here. Even in Worcester County it appears to be declining, currently found only in three northernmost towns (Bertin and Rawinski 2012).

Froelichia gracilis — slender cottonweed
This plant is native in North America from Iowa and Colorado to Texas and Mexico. In Massachusetts it is rapidly expanding, apparently along highways and other roads. As per Massachusetts County Checklist of 1999, at the time it was recorded only from 5 western counties (from the Connecticut Valley to Middlsex Co.). We first found it in eastern MA in 2008 in Myles Standish State Forest (Plymouth Co.), during a survey at the detention facility in the middle of the Forest; then in 2011 along Rt. 151 in Falmouth (Barnstable Co.); and in 2012, as a nearly continuous stretch along Rt. 3, embracing at least 4 adjacent towns: Pembroke, Norwell, Hanover, and Hingham (Plymouth Co.) as well as along Rt. 93 in Milton/Quincy (Norfolk Co.). In 2013 we collected and photographed cottonweed at Rt. 24 within the Blue Hills Reservation in Randolph (Norfolk Co.) and also along Rt. 225 (Carlisle Rd.) in Bedford (Middlesex Co.).

Pedicularis canadensis — wood betony
This plant deserves at least a watch-listed status. It is marked "uncommon" in the Flora of Worcester County by R. Bertin and T. Rawinsky (many historic locations, but only 7 current). In eastern MA, we've encountered it only twice during more than 10 years: once in Stony Brook Res., Boston in 2005 (and that clump appears to be gone now) and another small clump in Nasketucket Bay State Res., Mattapoisett, in 2013 (we have doubts if it is indigenous and not introduced with a sowing mix, because there was an entire constellation of unusual plants).