Herbs

Abutilon theophrasti velvet-leaf Malvaceae ABTH*; Bx, pb (DeCandido 2001), wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002); Q, lk; K, fs, p; R, fk, hs, wp; -     Abutilon theophrasti is an annual, C3 herb (Ward et al. 1999), stout, tap-rooted; 60-150 cm tall, branching, all parts softly hairy, dull green. A short-day (long-night) plant, flowering occurs about 12 weeks after emergence.  Leaves alternate, stalks about as long as blades, blades broadly heart-shaped, 10-15 cm long and wide, tip long-pointed, base lobed,  veins palmate, margin […]
Acalypha australis 3-seeded mercury Euphorbiaceae ACAU*; NY, rr; -   Acalypha australis is an annual herb, to 60 cm, from a taproot, stems erect, simple or branched, smooth or finely hairy; bright green to reddish, often appearing translucent or succulent, sap watery. Leaves alternate, stalks 1-8 cm long, blades 3-9 cm long, 2-5 cm wide, only slightly longer than stalks, narrowly egg-shaped to rhombic, tip blunt, base […]
Acalypha rhomboidea (A. virginica var. r) 3-seeded mercury; common copperleaf Euphorbiaceae ACRH; Bx, br, cn, pb, up, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002) (Stalter and Tang 2002), rr; Q, cu, f; K, p; R, bm, c, js; -      Acalypha rhomboidea is an annual herb, to 60 cm tall, from a taproot, stems erect, simple or branched, smooth or finely hairy; bright green to reddish, often appearing translucent or succulent, sap watery; senescent plants often turning reddish.  Leaves alternate, stalks 1-8 cm long, blades 3-9 cm long, 2-5 cm wide, only slightly longer than stalks, narrowly […]
Achillea millefolium yarrow Asteraceae ACMI; Bx, pb; NY, bl (Stalter and Tang 2002) (Stalter and Tang 2002); Q, a, cu, j, ri, tl; K, m; R, al, c, cl, d, e, jw, lp, mls, mm, ok, sm, sv; -    Achillea millefolium is an aromatic perennial herb, 20-100 cm tall, stem sparsely or not branched, sprouting from deep, extensive rhizomes, sparsely colonial; stems finely hairy to wooly, gray-green.  Leaves alternate, blade 3-15 cm long, to 2.5 cm wide, gray-green, lance-shaped, 2-4 times finely dissected, feathery, stem leaves sessile, over-wintering basal rosette larger, stalked. Leaves eaten by rabbits, […]
Acorus calamus (A. americanus) sweet flag Acoraceae ACCA; Bx, pb (DeCandido 2001); R, h; -     Acorus calamus is a perennial monocotyledon herb, colonial from underground stems (rhizomes), sweetly aromatic.  Leaves alternate, to 2 m long, 0.8-2.5 cm wide, grass-like or iris-like, crowded at base, overlapping like iris leaves, usually bright yellow-green, midvein off center (Magee 1981).  Flowers yellow-brown, minute, densely crowded on a spike 5-10 cm long, 1 cm wide, becoming […]
Actaea alba  (A. pachypoda) doll’s eyes; white baneberry Ranunculaceae ACAL; Bx, pb, vc; R, eb, gb; -     Actaea alba is a perennial herb, 40-80 cm tall, erect, plant poisonous, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves alternate, blade 2-3 times compound, leaflets egg-shaped, toothed, emerging with flowering stalk; blooming May-July.  Flowers white, small, radially symmetrical, petals to 0.4 cm long, spatula-shaped, stigma broad, no style; inflorescence an unbranched terminal cluster […]
Actaea rubra red baneberry Ranunculaceae ACRU; R (DeCandido 2001); - Actaea rubra is a perennial herb to 80 cm tall, erect, poisonous; roots associated with VA mycorrhizas (Brundrett and Kendrick 1988). Leaves alternate, blade 2-3 times compound, leaflets egg-shaped, toothed, hairy on veins below emerging with flowering stalk in May-July. Flowers white, small, radially symmetrical; inflorescence an unbranched terminal cluster (raceme). Fruit fleshy, red berries on slender stalks; […]
Aegopodium podagraria goutweed Apiaceae AEPO*p; Bx, br, pb, rd, wv (Yost et al. 1991); NY, hb, iw; K, p; R, c, gb; -     Aegopodium podagraria is a perennial herb 40-100 cm tall; erect, branched, aggressively colonial from rhizomes; crushed plant smelling strongly of fennel (licorice-like); basal rosette often semi-evergreen.  Leaves alternate, lower leaves with stalk to 40 cm, base clasping stem, upper leaves mostly stalkless, blade irregularly 3 x 3 compound with about 9 leaflets, leaflets egg-shaped, 3-8 […]
Aethusa cynapium fool’s parsley Apiaceae - Aethusa cynapium is an annual herb to 70 cm tall; plant poisonous.  Leaves alternate, 2-3 times pinnate, broadly deltoid, leaf segments narrow, pointed, shiny.  Flowers small, petals white, no sepals; in umbrella-shaped clusters to 5 cm wide, “secondary umbels with 3-4 bracts, curved downwards, linear, narrow, sharp-pointed” (NatureGate http://www.luontoportti.com/suomi/ en/kukkakasvit/fools-parsley; 16/12/2013); blooming and fruiting June-Sept.  Fruit dry, broadly […]
Agalinis fasciculata  (Gerardia f.) fascicled agalinis Scrophulariaceae AGFA(*); R, sv; -     Agalinis fasciculata is an annual herb to 1 m tall; a root hemiparasite, stems sometimes stout, rough-textured, finely hairy, branches angled.  Leaves opposite, (often alternate on branches) 0.1-0.2 cm wide, curved, rough textured, often with dense cluster of small leaves (fascicles) in axils.  Flowers purple, slightly bilaterally symmetrical, 2.5-3.5 cm long, broadly tubular, calyx 0.3-0.4 cm, […]
Agalinis purpurea  (Gerardia p.) smooth agalinis Scrophulariaceae AGPU; Q, j (Stalter and Lamont. 2002); R (DeCandido 2001); -     Agalinis purpurea is an annual herb to 120 cm tall; a root hemiparasite; stems simple to branched, 4-sided, smooth. Leaves opposite (often alternate on branches), largest leaves to 0.4 cm wide; small tufts of leaves in axils few or none. Flowers pink-purple, 2-4 cm long, broadly tubular, slightly bilaterally symmetrical, petal lobes bent back, hairy inside; […]
Agalinis tenuifolia  (Gerardia t.) common agalinis Scrophulariaceae AGTE; R, c, gb, h, lp, sb; - Agalinis tenuifolia is an annual herb, 20-60 cm tall; a root hemiparasite; stems thin, smooth, much branched. Leaves opposite (alternate near branch tips), linear, 0.1-0.6 cm wide. Flowers purple with dark markings, yellow throat stripes, slightly bilaterally symmetrical, tubular, 1-1.5 cm, tube longer than petal lobes, upper lip curved forward over stamens, much longer than lower lobes, […]
Agastache nepetoides yellow giant hyssop Lamiaceae AGNE; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R, c (possibly extirpated); - Agastache nepetoides is a perennial herb to 1.5 m tall; branched above, stem square, winged. Leaves opposite, egg-shaped, to 6 cm long, smaller above, margin toothed. Flowers pale yellow-green, tubular, bilaterally symmetrical, calyx 0.6 cm, lobes egg-shaped, tips blunt; inflorescence terminal, of dense spikes to 20 cm long, 1cm wide; blooming and fruiting July-Sept. Fruit dry, 1-seeded, (achenes) hairy at […]
Agastache scrophulariaefolia purple giant hyssop Lamiaceae  AGSC; Bx, vc; NY, iw (possibly planted); -    Agastache scrophulariaefolia is a perennial herb, about 1 m tall tall, branched above, stem sharply 4-angled, slightly winged.  Leaves opposite, egg-shaped, base slightly lobed, usually finely hairy below.  Flowers purple, irregular, petal tube 2-lipped, 5-lobed, stamens longer than petal lobes, calyx lobes triangular to lance-shaped; inflorescence of branched, racemes at top of plant; blooming and fruiting […]
Ageratina altissima  (Eupatorium rugosum) white snakeroot Asteraceae EURU; Bx, bg, br, bz, pb, sd, sf, up, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw, rr; Q, a, cu, f, j, u, wl; K, p; R, ah, c, a, cg, fk, gb, js, jw, lp, pr, sv, t; -     Ageratina altissima is a perennial herb, 30-150 cm tall, stems 1-3 together, from a knotty root crown, stems usually hairless below inflorescence. Plant poisonous (Kingsbury 1964).  Leaves opposite, stalk 10-30 cm long, blade 6-18 cm long, 3-12 cm wide, rather thin, egg-shaped, tip long-pointed, margin coarsely toothed.  Flowers bright white, 12-25 per head, bracteate base 0.3-0.5 […]
Ageratina aromaticum  (Eupatorium aromatica) smaller white snakeroot Asteraceae EUAR; R, ah (Lamont and Young 2002); -     Ageratina aromaticum is a perennial herb to 80 cm tall, much like A. rugosum, leaves smaller, thicker.  Leaves opposite, very short-stalked, blade 3-7 cm long, 2-5 cm wide, thick, firm, tip blunt to pointed, margin blunt-toothed (crenate).  Flowers white, 10-19 per head, no rays, basal bracts blunt to pointed; blooms Aug-Oct.  Fruit dry, small, 1-seeded, 5-angled plumed […]
Agrimonia eupatoria medicinal agrimony Rosaceae AGEU*; Bx, pb (DeCandido 2001); R (DeCandido 2001); -    Agrimonia eupatoria is a perennial herb from a rhizome, stems to 1 m tall, densely hairy below.  Leaves subopposite, at least on lower stem, pinnately compound, larger leaflets to 2.5 cm long, oblong, about opposite, interspersed with much smaller leaflets, hairy on both sides, margins toothed.  Flowers yellow, radially symmetrical, petals 5, to 0.5 cm long, […]
Agrimonia Genus harvest lice Rosaceae - Agrimonia Genus, these are perennial herbs from thick rhizomes; stipules leaf-like, margins deeply toothed. Leaves pinnately compound, with 3-many large leaflets, interspersed with numerous, small leaflets, margins toothed. Flowers yellow, petals 5, calyx at first spreading then coalescing at tips and forming a stiff beak in fruit, ovaries-2, expanded floral base (hypanthium) covered with hooked bristles.Inflorescence long, spike-like, with […]
Agrimonia gryposepala common agrimony Rosaceae AGGR; Bx, pb, vc; Q, cu; R, h; -     Agrimonia gryposepala is a perennial herb, from a stout rhizome, with fibrous roots; stem 30 cm to1.5 m tall, stout, glandular-hairy.  Leaves alternate, widely spaced, pinnately compound, leaflets 5-9, elliptic,1.5-5 cm long, to 2 cm wide, coarsely toothed, with 1-3 pairs of much smaller leaflets between larger pairs, hairless above, glandular-dotted below (use lens or […]
Agrimonia parviflora small-flowered agrimony Rosaceae AGPA; R (DeCandido 2001); -    Agrimonia parviflora is a perennial herb, from fibrous roots; stems stout, to 2 m tall, glandular-hairy.  Leaves alternate, pinnately compound, larger leaflets 11-23, lance-shaped, interspersed with numerous, small leaflets of variable shape and size, glandular below, hairy on veins, margin toothed, leaf midrib hairy.  Flowers yellow, radially symmetrical, petals 5, flower base hairy, 0.3 cm, covered […]
Agrimonia pubescens downy agrimony Rosaceae AGPU; Bx, pb (DeCandido 2001); Q, cu (Greller 1985); -    Agrimonia pubescens is a perennial herb to 1 m tall; stems stout, densely short-hairy; roots thick-tuberous.  Leaves alternate, widely spaced, pinnately compound, leaflets 5-13, narrow, velvety-hairy below, coarsely toothed, with 1-3 irregular pairs of much smaller leaflets between larger pairs, stipules lanceolate, toothed.  Flowers yellow, radially symmetrical, about 0.7 cm, petals 5, base of flower (calyx […]
Agrimonia rostellata woodland agrimony Rosaceae AGRO; Bx, pb (DeCandido 2001); Q, cu (Greller 1977, 1979, 1985); -    Agrimonia rostellata is a perennial herb; roots sometimes tuberous, stems to 1 m, branches slender, mostly hairless; stipules leaf-like, narrow, 1 cm wide or less, toothed.  Leaves alternate, pinnately compound, major leaflets 3-9, narrow, widest above middle, coarsely, bluntly toothed, glandular below (sprinkled with tiny dots), interspersed with 1-3 very small leaflets.  Flowers yellow, radially symmetrical, […]
Agrostemma githago corn cockle Caryophyllaceae AGGI*; Bx, pb (DeCandido 2001); -    Agrostemma githago is an annual herb to 1 m tall, stem thinly whitish-hairy.  Leaves opposite, stalkless (sessile), blade linear to lance-shaped, to 12 cm long, 1 cm wide.  Flowers reddish, radially symmetrical, to 4 cm wide, petals 5, widest near notched tops, calyx lobes to 4 cm long, linear, longer than petals, hairy; blooms June-Sept.  Fruit dry, […]
Alisma subcordatum water plantain Alismataceae ALSU; Bx, pb; Q, a, j; R, bm, gr (x), h, is, ml, rw, sb, w, wl, wp; - Alisma subcordatum is a perennial monocotyledon herb, colonial from rhizomes rooted in mud, flower stem triangular.  Leaves alternate, elliptic 3-18 cm long, 2-12 cm wide, secondary veins conspicuous, almost parallel to midrib.  Flowers white, petals 3, about 0.2 cm long, 3 sepals, in widely branched, pyramid-shaped clusters, branches whorled, July- Aug.  Fruit dry, 0.2 cm in donut-shaped cluster above […]
Alliaria petiolata  (A. officinalis) garlic mustard Brassicaceae ALPE*p; Bx, bg, br, bz, cf, pb, rd, sf, up, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002) (Stalter and Tang 2002), ct, hb, iw, n; Q, a, cu, dp, f, ft, rw, u, wl; K, p; R, ah, bd, bm, c, cg, cl, d, fw, gb, h, lp, se, sm, w, wp; -     Alliaria petiolata is a biennial or winter annual herb, becoming 5 cm to 1.9 m tall in flower, taprooted, initially forming a leafy rosette, then a simple or sparsely branched flowering stalk, robust plants sometimes with several stalks (Nuzzo 2005). Leaves alternate, young leaves with garlic smell when crushed, surface puckered, margins toothed; stalk […]
Allium canadense wild garlic; meadow garlic Liliaceae  Bx, pb (DeCandido 2001; Z. Wang 2017), vc (Zihao Wang 2016); Q (DeCandido 2001); R, rc; - Allium canadense perennial monocotyledon, 20-60 cm tall from a bulb 1-3 cm, coat of bulb a fibrous net, colonial from bulb offsets, smells strongly of onion or garlic. Leaves alternate, along the lower third of the flowering stem, blade flat, elongate, linear, 0.2-0.4 cm wide.  Flowers white-pink, small, radially symmetrical, 6 petals, on slender stalks to 3 cm […]
Allium tricoccum wild leek Liliaceae ALTR; Bx, vc (Z. Wang 2017); Q, cu (Greller 1977, 1979, 1985; M. Feller ca. 2003); R (DeCandido 2001); -    Allium tricoccum is a spring ephemeral, perennial, monocotyledon herb, from an oval-conical bulb, 2-5 cm long, it is colonial, probably from bulb offsets; roots produced in summer when leaves have died back, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves alternate, 1-2, blade broad, flat, 10-20 cm long, 2-6 cm wide, stalk slender, […]
Allium vineale field garlic Liliaceae ALVI*p; Bx, bg, br, pb, rd, sf, vc; NY, bl (Stalter and Tang 2002), ct, hb, iw, n; Q, a, cu, dp, f, fr, ft, j, wl; K, ow, p; R, ah, ar, bd, c, ca, cg, d, e, fw, gb, h, is, lp, mls, r, ro, sm, sv, w, wp; -     Allium vineale monocotyledon herb.Winter green perennial  or spring ephemeral from small bulbs 1-2 cm wide, usually accompanied by small, loosely attached bulb offsets, flat on one side, in a hard, tan outer “skin”, (Gargiullo personal observation), colonial from bulb offsets, forming large clumps; all parts smell strongly of onion/garlic when crushed.  Leaves slender, blade 10-20 […]
Althaea officinalis marsh mallow Malvaceae ALOF*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); -    Althaea officinalis is a perennial herb to 0.5-1.2 m tall, erect.  Leaves alternate, 5-10 cm long, egg-shaped, velvety textured, shallowly 3-lobed, tips pointed, base rounded to round-lobed, margin coarsely toothed.  Flowers pink, showy, radially symmetrical, 3 cm wide, petals 5, free, bases overlapping, sepals 5, ovary superior, stamens fused in a central column around style, […]
Amaranthus albus pale amaranth; tumbleweed Amaranthaceae AMAL(*); Bx, pb (DeCandido 2001); Q (DeCandido 2001); -     Amaranthus albus, is an annual C4 herb (Downton 1971; Costea and Tardif 2003), to 1 m, pale green to whitish, slender, erect to ascending, rigid, bushy-branched.  Leaves alternate, stalk elongate, blades of early stem leaves to 7 cm long, widest above middle, tip rounded, base tapered to stalk, pale green, veins conspicuous, leaves of flowering branches […]
Amaranthus blitoides  (A. graecizans) tumbleweed Amaranthaceae AMBL*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); R (DeCandido 2001); -    Amaranthus blitoides is an annual C4 herb (Downton 1971; Costea and Tardif 2003), to 60 cm, mostly stems prostrate, often pinkish to purplish, much branched.  Leaves alternate, stalk elongate, blade to 2 cm long, oblong to widest above middle, pale green, tip rounded, base tapered to stalk, often crowded near tips of stems.  Flowers greenish, very small, […]
Amaranthus blitum  (A. lividus) slender amaranth; purple amaranth Amaranthaceae AMBL*; Bx, br, cn, pb, sl; Q, rb; -      Amaranthus blitum is an annual C4 herb (Costea and Tardif 2003), coarse, stems prostrate to erect, 6-60 cm, pale green to reddish, rather fleshy. Possibly colonized by some mycorrhizal fungi (Costea and Tardif 2003).  Leaves alternate, stalk 1-3 cm long, blade 1-3 cm long, rhombic to egg-shaped, tip broadly notched, base wedge-shaped, dull dark green.  […]
Amaranthus cannabinus (Acnida c.) tidemarsh amaranth; water hemp Amaranthaceae AMCA; NY, iw; Bx, cm, pb; R (DeCandido 2001); - Amaranthus cannabinus is an annual C4 herb (Costea and Tardif 2003), 1-2.5 m tall, erect, stout. Leaves alternate, stalks to 5 cm, blade to 15 cm long, 4 cm wide, narrowly lance-shaped, upper leaves smaller, tapered to a blunt tip. Flowers green, inconspicuous, no petals, bracts at base 0.2 cm, scarcely bristly; sexes on different plants (dioecious); male […]
Amaranthus crispus crisp amaranth Amaranthaceae AMCR*; NY, bl (Stalter and Tang 2002); Q (DeCandido 2001); -     Amaranthus crispus  is an annual C4 herb (Costea and Tardif 2003), 20-60 cm, stem prostrate, much branched.  Leaves alternate, numerous, blade 0.5-1.5 cm long, egg-shaped to oblong, tip pointed to rounded, margin irregularly wavy (crisped).  Flowers inconspicuous, 0.1 cm, sepals linear, minutely bristle-tipped (use lens); inflorescences in leaf axils, 0.3-1 cm long.  Fruit dry, 1-seeded, flattened, to 0.2 […]
Amaranthus Genus amaranth Amaranthaceae -    Amaranth genus are annual C4 herbs, usually much branched.  Leaves alternate, stalked (petiolate), entire or with a wavy margin (sinuate).  Flowers very small, radially symmetrical, subtended by bracts, no petals, sepals dry, membranous; inflorescence of dense clusters (glomerate).  Fruit dry, small, thin-walled, 1-seeded, with a crown of dry stigmas.  
Amaranthus hybridus smooth pigweed Amaranthaceae AMHY*; Bx, br, sf, pb (DeCandido 2001), wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), hb; Q, a; K, p; R, hs, lc, sm, wp; -     Amaranthus hybridus is an annual C4 herb (Costea and Tardif 2003), to 2 m tall, from a reddish taproot; stems branching, finely wooly-hairy above, often pinkish or red (especially if stressed), generally smoother and darker than A. retroflexus.  Leaves alternate, stalk elongate, egg-shaped to rhombic, 5-15 cm long, tip blunt to acute, pale green to purplish below.  […]
Amaranthus pumilus sea beach amaranth Amaranthaceae AMPU; Q, rb; R (DeCandido 2001); -     Amaranthus pumilus is an annual C4 herb (Costea and Tardif 2003); monoecious, stems fleshy, branched, to 40 cm long, prostrate to reclining, reddish to pale green usually forming mats.  Leaves alternate, 1-2 cm long, in crowded rosettes toward tips of branches fleshy, pale blue-green, young leaves reddish, smooth, spoon-shaped, tip broadly rounded, often notched, base abruptly […]
Amaranthus retroflexus red pigweed Amaranthaceae AMRE*; Bx, cn, pb, up; NY, rr; Q, i, j (Stalter and Lamont 2002); K, p; R, sm; -     Amaranthus retroflexus is an annual C4 herb (Downton 1971; Costea and Tardif 2003), to 2 m tall, from a reddish taproot, stem stout, erect, branched, usually pale green but stressed plants often red-stemmed, at least below, mealy-wooly-hairy.  Leaves alternate, stalk elongate, blade to 10 cm long egg-shaped to diamond-shaped, hairy below at least on veins, veins […]
Ambrosia artemisiifolia common ragweed Asteraceae AMAR2; Bx, br, cn, pb, sf, sn, up, vc, wv (Yost et al. 1991) (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw, wr; Q, a, cu, f, I, j; K, do, fl, fs, m, pl; R, ah, bg, bm, c, cl, cs, d, fk, gb, gr, hs, jl, js, k, lp, lt, pm, sv, ty, v, w, wp, wt; -     Ambrosia artemisiifolia is an annual herb, 30-100 cm tall, from a taproot; the mycorrhizal fungus Opidium brassicae has been reported from the roots (Bassett and Crompton 1975); plant branching above, usually hairy.  Leaves opposite below, alternate above, once or twice pinnately divided, 4-10 cm long.  Flowers green, in small heads subtended by bracts, minute, radially symmetrical; flower heads […]
Ambrosia trifida great ragweed Asteraceae AMTR; Bx, pb, br, sf, wv (Yost et al. 1991) (Yost et al. 1991); NY, ct, hb; Q, a, cu, f; K, ow, p; R, ah, ar, bg, bk, c, cl, cs, ev, fk, gb, js, lp, pm, sb, se, sv, v, w, wp, wt; -     Ambrosia trifida is an annual, 1.5-2.8 m tall, roots fibrous, short taproot, stem rough-hairy.  Leaves opposite, stalks winged, blades palmately 3 lobed (occasionally 5 lobed or without lobes), to 15 cm long, 10-20 cm wide, tips pointed, base rounded, veins palmate at base of blade, secondary veins pinnate on lobes, margins toothed.  Flowers green, minute, in […]
Anagallis arvensis pimpernel Primulaceae ANAR; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); R(DeCandido 2001); -     Anagallis arvensis is a sprawling annual, 10-30 cm long, much branched, stem 4-angled.  Leaves opposite, elliptic to egg-shaped, 1-2 cm long, unstalked (sessile), each pair at right angles to next.  Flowers red-orange, about 0.6 cm wide, regular, 5-parted, long-stalked, closing in bad weather; blooming and fruiting June-Aug.  Fruit dry, hollow, a rounded capsule, splitting open around middle […]
Anaphalis margaritacea pearly everlasting Asteraceae ANMA; Q (DeCandido 2001); R, ca, k; -    Anaphalis margaritacea is a perennial 30-90 cm tall, colonial from rhizomes, stems erect, leafy, wooly-white, often rusty with age.  Leaves alternate, narrow, to 12 cm long, 2 cm wide, sessile, hairier below than above, margins curled backward.  Flowers yellow, very small, in heads almost entirely enclosed with dry, white bracts, tips showing in a button-like cluster; […]
Anemone quinquefolia wood Anemone Ranunculaceae ANQU; Bx, pb, vc; Q, cu; R, h; -     Anemone quinquefolia is a perennial herb to 20 cm tall (usually less), colonial from a slender rhizome.  Leaves alternate, palmately compound, 3-5 leaflets, wedge-shaped, coarsely, unevenly toothed.  Flowers white, to 2 cm wide, sepals 5 (petal-like), no petals, blooms, April-May.  Fruit dry achenes.  Wetland status: FACU.  Frequency in NYC: Infrequent.  Origin: Native.  Habitat: Rich, moist, open woods. 
Anemone virginiana thimbleweed Ranunculaceae ANVI; Bx, pb; -    Anemone virginiana is a perennial herb to 1 m tall, from a root crown, stems hairy.  Leaves along stem alternate, 2-3, palmately compound, segments egg-shaped, toothed or sharply lobed; 3 leaves whorled below inflorescence stalks.  Flowers greenish-white, to 1.3 cm, 5 sepals, no petals, stamens numerous, on stalks, sometimes with a pair of leaves below flowers; […]
Angelica atropurpurea purplestem angelica Apiaceae ANAT; Bx, pb (DeCandido 2001); NY, iw; R, h; - Angelica atropurpurea is a perennial herb, taprooted, stout, stem solitary ca 1.5 m tall, 3 cm diameter at base, purplish or purple-blotched.  Leaves alternate, pinnately compound, basal leaves ca. 20 cm long, often twice compound, 5-7 leaflets about 6 cm long, egg-shaped to lanceolate, margin toothed, small veins extend to tips of teeth, leaves progressively reduced […]
Angelica venenosa hairy angelica Apiaceae ANVE; Bx, pb (DeCandido 2001); -     Angelica venenosa is a perennial herb to 2 m tall, stems stout, hairy.  Leaves alternate, 2-3 times pinnate, leaflets elliptic, to 4 cm long, finely toothed, larger leaves long-stalked, upper leafs smaller with short, sheathing stalk, tubular, slender, to 1 cm wide, upper sheaths sometimes with little or no blade.  Flowers small, white in umbrella-shaped clusters, […]
Antennaria neglecta field-pussytoes Asteraceae ANNE; R, d, k; -    Antennaria neglecta is a perennial herb, 10-40 cm tall, colonial from creeping above ground stems that root at nodes (stolons).  Leaves alternate, largest ones basal and at ends of stolons (which become new basal rosettes); blade 1.5-6.5 cm long, 0.5-1.3 cm wide usually with 1 major vein, widest above middle, base tapered to stem, densely […]
Antennaria plantaginifolia plantain-leaved pussytoes Asteraceae ANPL; Bx, pb (DeCandido 2001); -    Antennaria plantaginifolia is a is a perennial herb, much like A. neglecta; basal leaves rounded, 1.4-6 cm long, 1.5-4 cm wide, with 3 or 5 major veins.  Flowers white, very small in heads. Fruit a plumed achene. Wetland status: UPL.  Frequency in NYC: Very infrequent.  Origin: Native.  Habitat: Dry, sterile soil of open woods or fields.  
Anthemis arvensis field chamomile Asteraceae ANAR2*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); R, c; -     Anthemis arvensis is an annual or biennial herb, to 50 cm tall, roots shallow fibrous from a very short tap-root, plant finely hairy, several stems from base, branched above, not ill-scented.  Leaves alternate, 2-3 times pinnate, 2-5 cm long, hairy, midrib narrowly winged, segments finely cut, narrow.  Flowers in heads subtended by bracts, daisy-like, ray flowers […]
Anthemis cotula mayweed; dogfennel Asteraceae ANCO*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); R (DeCandido 2001); -     Anthemis cotula is an annual, ill-scented, taprooted herb, 10-90 cm tall.  Leaves alternate, 2-3 times pinnately divided, about 4 cm long, finely divided, segments narrow.  Flower heads daisy-like, with 10-16 white ray flowers, sterile, 0.5-1 cm long; disk yellow, 0.5-1 cm wide, becoming raised at maturity, flowers numerous, bracts of head somewhat hairy.  Fruit dry 1-seeded (achenes) […]
Anthemis tinctoria yellow chamomile Asteraceae ANTI*; Q (DeCandido 2001); - Anthemis tinctoria is a Short-lived perennial herb, 30-70 cm tall, colonial from creeping above-ground stems, flowering stems erect few-branched, hairy.  Leaves alternate, pinnately divided, 2-6 cm long, midrib winged, segments toothed or divided, wooly below. Flower heads 3-4 cm wide, daisy-like, with 20-30 rays, disk about 1.5 cm wide, disk and ray flowers yellow, basal bracts small, […]
Anthriscus sylvestris wild chervil Apiaceae ANSY*; Bx, br; -    Anthriscus sylvestris is a biennial or short-lived perennial C3 herb (Pooter et al.1990) to 1 m tall, freely branched from a rosette from a stout taproot to 2 m long (Darbyshire et al. 1999).  Leaves alternate, 2-3 times pinnate, segments 1.5-5 cm, divided or deeply toothed.  Flowers white, radially symmetrical, small, 5-parted, ovary inferior; inflorescence of compound […]
Apocynum androsaemifolium spreading dogbane Apocynaceae APAN; Bx, pb (DeCandido 2001); K, p; R (DeCandido 2001); -     Apocynum androsaemifolium is a perennial herb to 80 cm tall; sap milky, acrid; colonial, stems often inclined, branched stems lack a central axis.  Leaves opposite, oblong to egg-shaped, to 8 cm long pale, often hairy below.  Flowers pinkish-white, radially symmetrical, 5-parted, tubular with spreading petal lobes, to 0.9 x 1 cm, fragrant; inflorescence of branched clusters, […]
Apocynum cannabinum Indian hemp Apocynaceae APCA; Bx, pb, sn, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), hb; Q, a, fr, ft, j, lk, tl, wl; K, fl, fs, m, p; R, ca, d, e, fk, gr, hs, jl, js, mm, ok, sb, ty, v, wt; -     Apocynum cannabinum is a perennial herb, to 1.5 m tall; colonial from rhizomes; stems erect, sap milky, sticky latex; branches curved upward, often red in full sun.  Leaves opposite, stalks 0.5-1 cm, blade narrowly oblong, to 11 cm long, tip pointed, base rounded to pointed, often pale-hairy below.  Flowers whitish, small, to 0.6 cm wide, radially […]
Aquilegia canadense wild columbine Ranunculaceae AQCA; Bx, pb (DeCandido 2001), wv (Yost et al. 1991) (planted); R, h (planted); -     Aquilegia canadense is a perennial, to 2 m (usually less than 50 cm), slender, branched stems often brownish, from a short rhizome, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves alternate, 2 times compound, leaflets lobed, bluntly toothed, dark green, slightly waxy-pale more so below, basal leaves larger, stalked, upper smaller, stalkless.  Flowers red […]
Aquilegia vulgaris European columbine Ranunculaceae AQVU*; Bx, pb (DeCandido 2001); -    Aquilegia vulgaris is a perennial herb to 2 m tall (usually less).  Leaves alternate, 2 times compound, leaflets lobed, bluntly toothed..  Flowers blue, white or pink, 3-4 cm, nodding, radially symmetrical but complex structure, 5 red petal tubes forming spurs, center with cluster of protruding stamens, May-June. Usually larger than A. canadensis.  Fruit dry, hollow, 5-parted, […]
Arabidopsis thaliana mouse-ear cress Brassicaceae ARTH*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); -    Arabidopsis thaliana is an annual or winter annual herb, to 40 cm tall, stem slender, sparsely branched or simple, hairy at base.  Leaves alternate on flowering stem, winter rosette leaves narrow, oblong, hairy, tip rounded, base narrowed to stalk; stem leaves few, narrow, pointed at both ends, stalkless, hairy.  Flowers white, 4-parted, petals to 0.4 cm […]
Arabis drummondii  Drummond’s rockcress Brassicaceae ARDR; R, js (planted); -    Arabis drummondii is a biennial herb; erect 30-90 cm tall, often waxy-pale green.  Leaves alternate, stalkless, lance-shaped, clasping-lobed at base, 2-8 cm long, margin entire to slightly toothed.  Flowers pink to white, petals 4, 0.5-0.8 cm long, narrow at base, wide above.  Fruit dry, hollow, elongate, linear, flattened, erect, 4-7 cm long, 0.1-0.2 cm wide, seeds in […]
Arabis hirsuta var. pycnocarpa hairy rock cress Brassicaceae ARHI; Q, a; R, g; -      Arabis hirsuta var. pycnocarpa is a biennial or short-lived perennial herb, to 80 cm tall, hairy.  Leaves alternate on flowering stem, to 3 cm long, numerous, lance-shaped, stalkless, lower ones clasping stem, hairy on both sides, basal rosette leaves to 8 cm, wider, with a stalk.  Flowers white to yellowish, petals 4, to 0.6 cm […]
Arabis lyrata lyre-leaf rock cress Brassicaceae ARLY; R (DeCandido 2001); -    Arabis lyrata is a biennial or perennial herb to 40 cm tall, tufted, stem branched from hairy base.  Leaves alternate on flowering stem, scattered, hairy, at least below, linear to narrowly spatula-shaped, lower ones often toothed; basal rosette leaves spatula-shaped, to 4 cm long, entire to pinnately lobed.  Flowers white, petals 4, to 0.8 cm long, […]
Aralia Genus spikenard Araliaceae - Aralia genus includes herbs, shrubs and small trees. Leaves doubly compound. Flowers small, greenish-white, 5-parted, radially symmetrical in panicles. Fruit fleshy, dark purple-black, with several seeds with hard outer coatings (pyrenes). Dispersed by birds.
Aralia hispida bristly sarsaparilla Araliaceae ARHI2; R, ro (possibly now extirpated); -     Aralia hispida is a perennial, colonial from stout rhizomes, stem bristly at base; about 70 cm tall.  Leaves alternate, 2 times pinnately compound, few, leaflets narrowly egg-shaped, to 10 cm long, tip pointed, margin toothed.  Flowers small, 5-parted, greenish, in several, long-stalked umbels; pollinated by bumble bees (Thompson et al. 1989), June-July.  Fruit fleshy, dark purple, tipped […]
Aralia nudicaulis wild sarsaparilla Araliaceae ARNU; Bx, g, pb, vc; Q, a, cu; R, ah, ap (E. Danielsen 4/2017), bd, cl, d, ev, gb, gr, lp, ro, t;  - Aralia nudicaulis is a perennial herb, about 30 cm tall; roots associated with vesicular-arbuscular mycorrhizal fungi (Berliner and Torrey 1989; Brundrett and Kendrick 1988). extensively colonial from rhizomes, stemless, leaves and flower stalks arise directly from rhizome, shoots of one rhizome can live to 25 years, and may be spaced to nearly 1 m apart, […]
Aralia racemosa spikenard Araliaceae ARRA; Bx, bg, vc; NY, iw; Q, a, cu, f; R (DeCandido 2001); -     Aralia racemosa  is a perennial herb, 0.5-2 m tall, stem stout, widely branched; clonal, roots large, spicy-aromatic.  Leaves alternate, to 80 cm long, twice compound with three primary leaflets, blades of secondary leaflets to 15 cm long, variable on same leaf, slightly hairy, heart-shaped, tip pointed, base unequally lobed, margin sharply double toothed.  Flowers tiny, white, […]
Arctium lappa great burdock Asteraceae ARLA*; Q (DeCandido 2001); K, p; R (DeCandido 2001); -    Arctium lappa is a coarse biennial herb, 1.5 –3 m tall in flower, from a large, fleshy taproot.  Leaves alternate, stalk of lower leaves solid; rosette leaves very large, to 50 cm long, 30 cm wide, base lobed, stem leaves becoming progressively smaller upwards.  Flowers purple, in heads 3-4 cm wide, base covered with hooked spines inflorescence stem […]
Arctium minus common burdock Asteraceae ARMI*; Bx, br, bz, pb, sf, sn, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw, n, wr; Q, a, cu, ft, j, rw, wl; K, ow, p; R, bg, cl, cs, fk, h, hs, wp, wt; -     Arctium minus is a biennial herb to 1.5 m tall in flower, coarse plant from a large, fleshy taproot.  Leaves alternate, forming a rosette the first year, rosette may remain small until the second growing season, stalk of lower leaves hollow; blade to 50 cm long, 40 cm wide, heart-shaped, thick, dull green, surface wrinkled […]
Arenaria serpyllifolia thyme-leaved sandwort Caryophyllaceae ARSE*; Bx, pb (DeCandido 2001); NY, bl (Stalter and Tang 2002); Q, j (Stalter and Lamont. 2002) ; K (DeCandido 2001); R, hs; -     Arenaria serpyllifolia is a small annual herb, to 20 cm, diffusely branched, wiry, stems slightly hairy, internodes usually longer than leaves.  Leaves opposite, egg-shaped, margin hairy, rough textured, to 0.5 cm long, 0.4 cm long, similar to common chickweed but leaves smaller.  Flowers white, petals 5, entire, usually shorter than sepals; blooms May-Aug.  Fruit dry, hollow, an […]
Arisaema triphyllum Jack-in-the-pulpit Araceae ARTR; Bx, bg, pb, vc, wv (Yost et al. 1991); NY, hb; Q, a, cu; R, bd, gb, h, lt, t; -     Arisaema triphyllum is a perennial monocotyledon herb living to 25 years (Bierzychudek 1982), ca 3-20 cm tall, from an acrid corm containing sharp calcium oxalate crystals (Kingsbury 1964), roots grow out of the corm in spring as shoot emerges, and die back in late summer as aerial parts senesce and die; roots associated with VA […]
Aristolochia clematis birthwort Aristolochiaceae ARCL*; Bx, pb (DeCandido 2001); -    Aristolochia clematis is a poisonous (Kingsbury 1964) perennial herb, to 1 m tall, stems ascending or reclining.  Leaves alternate, broadly heart-shaped to 10 cm long and wide, tip blunt, base with wide , well separated, rounded lobes, pale below.  Flowers yellow, no petals, bilaterally symmetrical, calyx tubular, to 3 cm long, base enlarged, top with one […]
Armoracia rusticana horseradish Brassicaceae AMRU*; Bx, pb (DeCandido 2001); - Armoracia rusticana is a perennial herb to 1 m tall, erect, from a thick, woody, vertical tap root. Leaves alternate, basal leaves to 30 cm long, base lobed, margin round-toothed (crenate), long-stalked, stem leaves narrow, smaller, short-stalked to stalkless, the lowest sometimes pinnately divided. Flowers white, 4-parted, petals to 0.8 cm; May-July. Fruit dry, hollow capsule, rounded to […]
Artemisia annua annual wormwood Asteraceae ARAN*; Bx, pb (DeCandido 2001); Q, j; K, fs, p; R, hs, m, sm; -     Artemisia annua is an annual herb, erect, much branched, 30 cm to 3 m tall; sweet smelling.  Leaves alternate, about 2-10 cm long, fern-like, two or three times pinnately divided, ultimate segments linear, margins toothed, persistent into winter.  Flowers pale greenish, very small, in compact heads that arise from a bract-covered base (receptacle), flowers tubular, radially […]
Artemisia biennis biennial wormwood Asteraceae ARBI*; R (DeCandido 2001); -    Artemisia biennis is an annual to biennial herb, not aromatic, 30 cm to 3 m tall.  Leaves alternate, blade 5-15 cm long, deeply, pinnately divided, lobes toothed to divided.  Flowers greenish yellow, very small, in compact heads that arise from a bract-covered floral base (receptacle), flowers tubular, radially symmetrical (disc flowers) only, heads 0.2-0.3 cm high, […]
Artemisia campestris  (A. caudata or A. campestris spp. caudata) field sagewort; tall wormwood; wild sage Asteraceae ARCA2; Q, j, tl; -     Artemisia campestris is a biennial or perennial herb, 10 cm to 1 m tall from a taproot, scarcely aromatic, forming a leafy crown the first year, old inflorescences sometimes persisting with new growth.  Leaves alternate, 2-4 times pinnate, 2-10 cm long, 1-4 cm wide, finely dissected, mostly hairless, segments alternate, linear to thread-like, mostly less […]
Artemisia Genus wormwood Asteraceae - Artemisia Genus herbs or sub-shrubs, they are Annuals, biennials, or perennials. Usually aromatic. Leaves alternate, mostly pinnately divided to finely dissected. Flowers very small in small heads. All disk flowers; the outer (involucral) bracts of the heads mostly papery, thin, overlapping, in at least 2 rows . Fruit dry, very small achenes without appendages. (plumes, teeth, […]
Artemisia ludoviciana white sage Asteraceae ARLU*; R, hs (Stalter and Munir 2002); -    Artemisia ludoviciana is a perennial herb, 30 cm to 1 m tall, colonial from rhizomes; stems white wooly-hairy, unbranched below inflorescence.  Leaves alternate, 3-10 cm long, 1 cm wide, lance-shaped, entire to toothed or deeply lobed, white-wooly on both sides, or green above.  Flowers greenish, very small, in compact heads that arise from a bract-covered floral […]
Artemisia stelleriana beach wormwood; dusty miller Asteraceae ARST*; Q, j (Stalter and Lamont 2002); -     Artemisia stelleriana is a perennial herb, 30-70 cm tall, plant not aromatic; colonial from underground stems (rhizomes), stems unbranched below.  Leaves alternate, 3-10 cm long, including stalk, 1-5 cm wide, sparsely but deeply pinnately lobed, lobe tips rounded.  Flowers yellowish, very small, tubular, radially symmetrical, in compact heads that arise from a bract-covered floral base (receptacle), […]
Artemisia vulgaris mugwort Asteraceae ARVU*; Bx, br, cm, cn, g, ht, pb, rd, sf, sn, up, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw, n, rr, wr; Q, a, cu, dp, f, fa, fr, i, j, lk, rb, rw, tl, vb, wl; K, do, fl, fs, ft, m, ow, p, pl; R, ah, ar, bd, bk, bm, c, ca, cb, cg, cl, cs, d, e, ev, fk, fw, gb, go, gr, h, hs, is, jl, js, k, lc, lp, lt, mc, mls, mm, ok, pm, pr, r, sb, se, sm, sv, t, ty, u, v, w;  - Artemisia vulgaris is a perennial herb, 0.5-2 (3) m tall, aromatic, aggressively spreading by rhizomes, forming a dense root-mat 7-18 cm deep; lower stem turning brown and woody as inflorescence develops (Barney and DiTommaso 2003). Roots are colonized by arbuscular mycorrhizal fungi which contribute to both phosphorus and nitrogen nutrition in  N, P deficient soils. […]
Asarum canadense wild ginger Aristolochiaceae ASCA; Bx, br, pb, wv (Yost et al. 1991); Q: f (M. Feder); R, cb, cr (U. Lorimer 2017), lt, w;  -     Asarum canadense is a perennial, herbaceous ground cover, about 10 cm tall, slowly clonal from short, extensive system of rhizomes, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); hairy.  Leaves opposite, in pairs at ends of rhizome branches, heart- to kidney-shaped, dark, matte green, 8-12 cm wide.  Flowers reddish-brown, petals none, calyx broadly cup-shaped, 3 […]
Asclepias amplexicaulis blunt-leaved milkweed Asclepiadaceae  ASAM; Bx, vc; R (DeCandido 2001); -    Asclepias amplexicaulis is a perennial herb from a rhizome, to 80 cm tall, sap milky, plant usually pale, waxy-green (glaucous).  Leaves opposite, oval to broadly oblong, 7-15 cm long, tip blunt, base usually lobed, clasping stem, margin often wavy.  Flowers greenish-purple and pinkish, radially symmetrical (regular) to 1.8 cm long (see A. syriaca); inflorescence, terminal, umbrella-shaped, on […]
Asclepias exaltata poke milkweed Asclepiadaceae ASEX; Bx, vc; Q; R (DeCandido 2001); -     Asclepias exaltata perennial herb from a rhizome, stem 50-150 cm tall, sap milky.  Leaves opposite, 7-11 pairs, stalk 1-2 cm long, blade 10-30 cm long, 10 cm wide, broadly elliptic, thin, elongate-pointed at both ends, usually hairless.  Flowers white to dull purple, radially symmetrical (regular), petal lobes to 1 cm long, hoods 0.4 cm (see A. syriaca); […]
Asclepias Genus milkweed Asclepiadaceae -    Asclepias Genus are perennial herbs from thick root or vertical root crown, sap is a milky, thick latex, (except A. tuberosa) often containing toxic cardiac glycosides (chemically a sugar and steroid combined).  Leaves opposite to whorled (alternate in A. tuberosa).  Flowers radially symmetrical, 5-parted, petals (corolla) fused at base, petal lobes usually reflexed sharply backward; stamens fused around […]
Asclepias incarnata swamp milkweed Asclepiadaceae ASIN; Bx, pb; Q, j, wl; K, p; R, ah, c, e, h, gr (x), is, lp, sb, v; -     Asclepias incarnata is a perennial herb to 1.5 m tall, stems leafy, branched above, stems single or clumped, sap milky.  Leaves opposite, to 20 cm long, lance-shaped, tip pointed, base blunt to slightly lobed.  Flowers pink about 0.8 cm, in umbrella-shaped clusters insect pollinated, July- Aug.  Fruit dry pods, narrow, to 9 cm, long pointing upwards, finely […]
Asclepias purpurascens purple milkweed Asclepiadaceae ASPU; Bx, pb, vc; Q (DeCandido 2001); R, gb; -     Asclepias purpurascens is a perennial herb to 1 m tall; stem erect, finely hairy, sap milky.  Leaves opposite, stalk to 0.8 to 2.5 cm long, blade 10-15 cm long, elliptic to egg-shaped, finely hairy below, smooth above, base contracted.  Flowers dark purple, to 1 cm, radially symmetrical (see A. syriaca); inflorescence umbrella-shaped, one or a few flowered, […]
Asclepias quadrifolia four-leaved milkweed Asclepiadaceae ASQU; Bx, vc; R (DeCandido 2001); -     Asclepias quadrifolia is a perennial herb to 50 cm tall, stems slender, mostly unbranched, sap milky, lower stem leafless, upper stem usually with 3 leaf-bearing nodes.  Leaves of upper and lower nodes opposite, small, middle node with a whorl of four, much larger leaves, blades thin, to 12 cm long, lance to egg-shaped, tip long-pointed, […]
Asclepias syriaca common milkweed Asclepiadaceae ASSY; Bx, cm, pb, sn, vc, wv (Yost et al. 1991); NY, ct, wr; Q, a, cu, fr, i, j, rb, tl, wl; K, fl, m, pl; K, fl (M. Feder 2016); R, bk, c, ca, cg, e, hs, jw, lp, mc, mls, pr, se, sm, ty, wp, wt; -     Asclepias syriaca is a perennial herb, 1-2 m tall, stem stout, hairy, usually unbranched, colonial from massive, white, creeping rhizome with storage side shoots; roots can reach over 1 m deep; sap milky, toxic.  Leaves opposite, stalk 0.5-1.5 cm long, blade 10-26 cm long, 40-18 cm wide, oblong to broadly oval, thick, tip blunt or […]
Asclepias tuberosa butterfly weed Asclepiadaceae ASTU; Bx, pb, vc; Q, i, j, tl; K; R, sb, sm; -     Asclepias tuberosa is a perennial herb, to 70 cm tall, hairy, simple to branched above; stems emerging from a the crown of a stout tap root in May, living up to 25 years, not flowering before about 6 years, 1-few stems per plant, no vegetative reproduction (Klemow and Raynal 1986; Wyatt 1980).Sap clear Leaves alternate […]
Asclepias viridiflora green milkweed Asclepiadaceae ASVI; R, gb, sc; -     Asclepias viridiflora is a perennial 30-80 cm tall, stems erect to prostrate, often numerous in same area, possibly colonial.  Leaves opposite, shape very variable, thick, oval to lance-shaped , tip blunt.  Flowers green, radially symmetrical (see A. syriaca), about 1 cm long, crowded, in umbrella-shaped clusters with little or no stalk.  Fruit dry, hollow pods 8-11 cm long, […]
Asparagus officinalis wild asparagus Liliaceae ASOF*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, tl; K, fl, pl; R (DeCandido 2001); -     Asparagus officinalis is a perennial herb; a monocotyledon, to 2 m tall, plant green, upright, ultimate branches feathery, 0.8-1.5 cm, hair-thin.  Leaves reduced to inconspicuous scales, branches and stems carry out photosynthetic functions.  Flowers green, 0.3-0.5 cm wide, radially symmetrical, 6-parted, bell-shaped; pollinated by insects, May-June.  Fruit red, fleshy, 0.8 cm, eaten by birds, which disperse the […]
Atriplex arenaria  (A. cristata, A. pentandra) seabeach orach Chenopodiaceae ATAR; Q, j (Stalter and Lamont 2002); K, pl; R (DeCandido 2001); -    Atriplex arenaria is an annual C4 herb (Jacobs 2001), 20- 50 cm tall, erect to prostrate, widely branched.  Leaves opposite below, alternate above, stalk short, blade 1-3 cm long, oblong, elliptic, or widest above middle, tip rounded to tapered, base tapered, surface silvery-scaly, margins mostly smooth.  Flowers tiny, dull, sexes separate, male spikes 1-2 cm long, female flowers […]
Atriplex patula spearscale orach; spear saltbush Chenopodiaceae ATPA4*; Bx, pb; NY, bl (Stalter and Tang 2002), iw; Q; j, wl, rb, K, fl, m; R, c, gr, hs, pr, w; -     Atriplex patula is an annual C3 herb (Jacobs 2001), stem to 1 m, erect to prostrate, widely branching, slender, finely ribbed, gray-green, stem veins often reddish, especially at nodes.  Leaves alternate above, opposite below, 4-12 cm long, larger leaves mostly arrow-shaped, tip pointed, base flat or with flaring lobes, corners sharply pointed outward, smaller leaves often lance-shaped […]
Aureolaria flava  (Gerardia f.) smooth false foxglove Scrophulariaceae AUFL; Bx, pb (DeCandido 2001); -     Aureolaria flava is a perennial, root hemiparasitic herb, 1-2 m tall, stems smooth, waxy pale-green, often purplish, branched near top.  Leaves opposite, lower leaves deeply, pinnately lobed, lobes widely spaced, often waxy pale-green, upper leaves toothed to smooth-margined.  Flowers yellow, 3.5-5 cm long, broadly tubular, petal lobes 5, unequal, tips rounded, July-Sept..  Fruit dry, a capsule 1.2-2 […]
Baptisia tinctoria yellow wild indigo Fabaceae BATI; Q, j; R, gr; -     Baptisia tinctoria is a perennial herb to 1 m tall, from a thick rhizome, stem freely branched.  Leaves alternate, 3-parted, leaflets1-3 cm long, egg-shaped, tip rounded to indented.  Flowers yellow to 0.8-1.3 cm long, pea-flower-shaped, in numerous short, unbranched clusters at tips of branches, blooming June-July.  Fruit dry, pods flattened to rounded, tip beaked, 0.8-1.5 cm long, […]
Barbarea verna early yellow rocket; early wintercress Brassicaceae BAVE*; Bx, rd; Q (DeCandido 2001); R, gb; -     Barbarea verna is a biennial or short-lived perennial herb to 80 cm, stems simple or branched above.  Leaves alternate, basal leaves to 20 cm long, pinnately divided, blade roughly egg-shaped, lateral lobes 4-10 pairs, terminal segment largest, margin broadly toothed, stem leaves smaller, lobes narrow, margins entire.  Flowers bright yellow, 4-parted, petals to 0.8 cm long, […]
Barbarea vulgaris yellow rocket; winter cress Brassicaceae BAVU*; Bx, pb, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002); Q, j, wl; K, p; R, js, lp, mls, r; -     Barbarea vulgaris is a biennial or short-lived perennial herb, 20-80 cm tall, erect from a taproot to 50 cm deep, secondary root system fibrous, extensive, initially forming an overwintering rosette, which can grow at temperatures below 5° C, flowering stems one to several, branched above, stem with 8 ridges, dark green.  Leaves alternate, winter rosette […]
Bartonia virginica bartonia Gentianaceae BAVI; R, h; -     Bartonia virginica is an annual to biennial herb, roots are associated with and plant dependent upon a fungus (mycotrophic); stem slender, to 40 cm tall, unbranched below inflorescence.  Leaves reduced to opposite scales, yellow-green.  Flowers yellowish, bell-shaped, radially symmetrical, to 0.4 cm, petals fused at base, lobes 4, narrow, margin usually toothed.  Fruit dry, capsule cylindrical, seeds […]
Bassia hirsuta bassia Chenopodiaceae BAHI*; Q, j (Stalter and Lamont. 2002); -     Bassia hirsuta is an annual C3 herb (Jacobs 2001), to 40 cm tall, bushy-branched, turning pink in autumn.  Leaves alternate, to 1.5 cm long, fleshy, linear, nearly cylindrical, hairy, blunt-tipped.  Flowers solitary in axils, 0.1 cm, 5 sepals, incurved.  Fruit dry, 0.3 cm long, 0.2 cm wide, with 3 tubercles; Aug.-Oct.  Wetland status: OBL.  Frequency in NYC: Very […]
Berteroa incana hoary alyssum Brassicaceae BEIN*; Q, j (Stalter and Lamont. 2002);  -     Berteroa incana is an annual to short-lived perennial herb, gray-green, stiff, erect, to 70 cm tall, branched above, stems downy.  Leaves alternate, 2-5 cm long, narrow, widest above middle (oblanceolate), margin smooth, gray-green, ca 3 cm.  Flowers white, 3 mm wide, petals 4, deeply 2-lobed, narrowed to base, flowers at top of elongating crowded racemes, blooming […]
Bidens aristosa showy beggar-ticks Asteraceae BIAR*; Bx, pb (DeCandido 2001); R (DeCandido 2001); -     Bidens aristosa is an annual or biennial 30-150 cm tall.  Leaves opposite, pinnately divided, 5-15 cm long including stalk 1-3 cm , leaf segments linear, toothed or lobed.  Flowers: ray flowers about 8, yellow, 1-2.5 cm long, disk 0.8-1.5 cm wide, basal bracts of flower head linear, 0.5-1 cm long, outer bracts shorter than inner […]
Bidens bipinnata Spanish needles Asteraceae BIBI; Bx, pb (DeCandido 2001); NY, hb; Q, j (Stalter and Lamont. 2002); K (DeCandido 2001); R, c -     Bidens bipinnata is an annual herb, 30-170 cm tall, stem square.  Leaves opposite, stalk 2-5 cm, blade about 2-15 cm long, 2-3 times pinnately divided, ultimate segments usually rounded.  Flowers yellow, to 0.6 cm wide, longer than wide, rays few, usually shorter than disk, outer bracts at base of flower head 7-10, shorter than the inner, […]
Bidens cernua nodding beggar-ticks; bur marigold Asteraceae BICE; R (DeCandido 2001); -     Bidens cernua is an annual herb 10-100 cm tall.  Leaves opposite, narrowly lance-shaped, stalkless, often fused across base, blade 4-20 cm long, 0.5-4.5 cm wide, margin usually toothed.  Flowers yellow, ray flowers 0 or 8, (when present), disk 1.2-2.5 cm wide, usually nodding, papery bracts among disk flowers yellowish; basal bracts leafy, spreading, longer than disk, […]
Bidens connata purplestem beggarticks Asteraceae - Bidens connata is an annual herb, 10 cm to 2 m tall, mostly smooth, stem green to purple. Leaves opposite, simple, narrow, to 15 cm long, 4 cm wide, margins coarsely toothed, or larger ones often deeply 3-lobed (rarely 7 lobed), tip long-pointed, base tapered, stalk to 3 cm long, often winged. Flowers dark yellow-orange, heads mostly […]
Bidens coronata tick-seeded sunflower Asteraceae BICO2; Q, i; R, c; -     Bidens coronata is an annual or biennial herb, 30 cm to 1.5 m tall.  Leaves opposite, to 15 cm, pinnately divided, 3-7 narrow, toothed segments, leaf stalks ca 1 cm.  Flowers bright yellow, showy, rays about 8, large, 1-2.5 cm long, disk yellow, 0.8-1.5 cm wide, anthers longer than disk flowers, purple-black, blooming and fruiting July-Oct.  […]
Bidens frondosa devil’s beggar ticks  Asteraceae BIFR; Bx, br, bz, sd, up, wv (Yost et al. 1991); Q, a, cu; i; K, p; R, bd, bk, c, fk, gb, is, js, lp, sv, ty; -    Bidens frondosa is an annual, 20 cm to 1.2 m tall, generally hairless, stem often purple, especially if water stressed.  Leaves opposite, pinnately compound, stalks (petioles) 1-6 cm long, leaflets 3-5, to 10 cm long, 3 cm wide, narrow, toothed, the terminal leaflet stalked.  Flowers yellow, heads small, rounded, rays few if any, disk orange, to 1 […]
Bidens Genus beggar-ticks Asteraceae -    Bidens is a genus of herbs in the family Asteraceae.  Leaves opposite, simple to much divided.  Flowers mostly yellow, ray flowers sterile (see Genus Aster), few, mostly 8, if any, often shorter than disk; basal bracts in two rows, the outer green, large, longer than the inner membranous bracts; style branches of disk flowers short, hairy, flattened, […]
Bidens laevis smooth beggar-ticks; showy bur-marigold Asteraceae BILA; Q (DeCandido 2001); -    Bidens laevis is an annual herb to perennial, 25-100 cm tall, much like B. cernua, not nodding as much. Leaves opposite, stalkless, margins toothed; sometimes nodding in fruit. Flowers yellow, ray flowers about 8, 1.5-3 cm long, disk 1.5-2.8 cm wide, papery bracts among red-tipped disk flowers, basal bracts hardly leafy; flower heads erect; blooms and […]
Bidens vulgata tall beggar-ticks Asteraceae BIVU; Bx, pb; Q, j; R, sv; -   Bidens vulgata is an annual herb to 1.5 m tall, stems often reddish, smooth to hairy.  Leaves alternate, stalked, pinnate, leaflets 3-5, narrow, tip long-pointed, base wedge-shaped, margins toothed (sometimes lobed).  Flowers pale yellow, rays inconspicuous, disk flowers 40-60, flower heads hemispheric, 1-2.5 cm wide, outer bracts leaf-like 10-20, unequal, 1-4 cm long, loose, densely hairy, […]
Blephilia hirsuta hairy wood mint Lamiaceae BLHI; Q (DeCandido 2001); -    Blephilia hirsuta is a perennial herb, to 80 cm tall, stems 4-sided, long-hairy, colonial from rhizomes.  Leaves opposite, stalks 1-2 cm, blade 4-8 cm long, egg-shaped, margin toothed tip pointed, base rounded to slightly lobed,.  Flowers pale blue with purple spots, tubular, bilaterally symmetrical, 2-lipped, hairy, tube elongate, to 1.4 cm long, in dense, crowded clusters […]
Boehmeria cylindrica false nettle Urticaceae -     Boehmeria cylindrica is a perennial herb, 40-100 cm tall, nettle-like but unarmed, stem erect, unbranched, opaque, smooth.  Leaves opposite, stalk elongate, blade egg-shaped, base rounded, tip long-pointed, veins palmate at base, margin coarsely toothed.  Flowers greenish, tiny, no petals, sexes on separate plants (dioecious), in dense, rounded clusters along axis of slender, axillary flower spikes; blooming […]
Brassica nigra black mustard Brassicaceae BRNI*; Q, j (Stalter and Lamont. 2002); R (DeCandido 2001);  -     Annual to 1.5 m tall, stem rough-hairy below, hairless, waxy-pale above.  Leaves alternate, lower leaves, divided, with a large terminal lobe, lobes toothed, upper leaves toothed, smaller, all leaves stalked.  Flowers yellow, to 1 cm, 4 petals.  Fruit capsules linear pointing upward, to 2 cm long, 4-sided, seeds 0.2 cm, wrinkled, contain sinigrin, a precursor of a […]
Brassica rapa field mustard; turnip; bok choy; napa cabbage Brassicaceae BRRA*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, j (Stalter and Lamont. 2002); K, p; R (DeCandido 2001); -     Brassica rapa is an annual herb to 80 cm tall, often pale, waxy, succulent.  Leaves alternate, sparsely bristly, lower leaves pinnately lobed, margins wavy, stalked, upper leaves toothed to entire, clasping stem.  Flowers pale yellow, radially symmetrical, 1 cm wide, 4 petals.  Fruit dry capsule linear, 3-5 cm, pointing upward on stalks 1-2 cm long; blooming and […]
Cabomba caroliniana fanwort Cabombaceae CACA(*); R, h; -    Cabomba caroliniana is a rooted, submerged aquatic, to 2 m long from a creeping rhizome; branched.  Leaves opposite, stalk to 3 cm, blade to 5 cm wide, round in outline, palmately, finely dissected with linear segments, a few floating leaves, when present, to 2 cm, linear, constricted in middle where stalk is inserted on underside.  […]
Cakile edentula sea-rocket Brassicaceae CAED; Bx, pb, sn; Q, j, rb; K, fl, m, pl; R, c, wp; -    Cakile edentula is an annual herb, 10-80 cm tall, fleshy, stems jointed, branching.  Leaves fleshy, widest above middle, narrowed to base, few rounded teeth.  Flowers blue to white, 0.5 cm, 4-parted, cross-shaped; blooming June-Oct.  Fruit green, fleshy, jointed transversely, top part rounded with pointed tip, usually larger than lower part, lower part top-shaped, to 0.8 cm, persistent […]
Callitriche heterophylla water-starwort Callitrichaceae CAHE; R (DeCandido 2001); -     Callitriche heterophylla is an annual herb, small aquatic or rooted in mud, to 20 cm long, rooting from lower nodes, often in dense patches, stems thread-like, compressed.  Leaves opposite, those below water linear, to 1.5 cm long, leaves above water spatulate, crowded into a small rosette at stem tips, margins entire.  Flowers (use hand lens) in […]
Callitriche palustris  (C. verna) vernal water-starwort Callitrichaceae CAPA; R, rc; - Callitriche palustris is an annual herb, small aquatic or rooted in mud, to 20 cm long, often in dense patches, rooting from lower nodes. Leaves opposite, those below water, linear, to 1.5 cm, leaves above water spatulate, crowded into a small rosette at stem tips, margins entire;  Flowers (use hand lens) in leaf axils, 1 stamen, one […]
Callitriche terrestris  (C. deflexa) terrestrial water-starwort Callitrichaceae CATE; Bx, vc; -     Callitriche terrestris is an annual herb, minute, stems tufted, to 5 cm long (usually much less), bright green, appearing almost moss-like, simple to much-branched, rooting at nodes.  Leaves opposite, to 0.5 cm long, widest above middle.  Flowers barely visable with hand lens, unisexual, one of each sex or separately in each leaf axil, no petals or […]
Caltha palustris marsh marigold Ranunculaceae CAPA2; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q (DeCandido 2001); R (DeCandido 2001); (some of these are probably planted); -     Caltha palustris is a perennial herb, to 60 cm tall, poisonous when fresh. Contains an unstable oil, protoanemonin (Kingsbury 1964). Stems hollow, branched above.  Leaves alternate, broadly heart-shaped to kidney-shaped, base deeply lobed, with broad sinus, tip rounded, margin toothed, lower leaves long-stalked, upper becoming almost stalkless.  Flowers bright yellow, to 4 cm wide, sepals 5-9, […]
Camelina sativa false flax Brassicaceae CASA*; Q (DeCandido 2001); -     Camelina sativa is an annual or winter annual, to 70 cm tall, stems erect, branched above, smooth to slightly fine-hairy.  Leaves of basal rosette narrowly spatula-shaped, base tapered to a stalk, stem leaves lance-shaped, clasping stem, base lobed.  Flowers yellow, petals 4, small.  Fruit dry, capsule oval, to 0.9 cm long, 0.7 cm wide, widest above middle, […]
Campanula rapunculoides creeping bellflower Campanulaceae CARA*; Bx, pb (DeCandido 2001); R (DeCandido 2001); -    Campanula rapunculoides is a perennial herb 40 cm to 1 m tall, from a rhizome with numerous, fleshy roots, stem erect.  Leaves alternate, lower leaves long-stalk, blade egg to heart-shaped, upper leaves increasingly narrower with shorter stalks, margin coarsely toothed, tip pointed, base rounded to lobed.  Flowers blue, tubular, narrowly bell-shaped, 2-3 cm long, nodding, in […]
Capsella bursa-pastoris shepherd’s purse Brassicaceae CABU2*; Bx, br, pb, sd, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb; Q, j; K, p; R, hs; -     Capsella bursa-pastoris is an annual or winter annual herb, to 60 cm (usually much shorter) in fruit, few branches.  Leaves alternate, those of basal rosette to 10 cm long, narrow, pinnately lobed, wider near top, overwintering, stem leaves narrow much smaller, linear, usually toothless, clasping stem.  Flowers white, 4-parted, petals to 0.4 cm, sepals shorter, crowded […]
Cardamine concatenata  (Dentaria laciniata) cut-leaved toothwort Brassicaceae CACO3; Bx, br, pb vc (C. Liriano 4/2017); NY, iw; R, gb (E. Danielsen 4/2017), w; -     Cardamine concatenata is a perennial, spring ephemeral herb; 20- 40 cm tall, sparsely colonial from a fleshy, peppery tasting rhizome; stems hairy above.  Leaves alternate, 3-parted (appearing 5-parted from deeply divided segments) with narrow, palmate, toothed lobes, basal leaves dying before plant flowers.  Flowers white to pale lavender, petals 4, to 1.9 cm long, 0.5 cm wide, […]
Cardamine diphylla  (Dentaria d.) broad-leaved toothwort Brassicaceae CADI; Bx, pb, vc (C. Liriano 4/2017); NY, iw; -     Cardamine diphylla is a perennial, spring ephemeral herb; stems to 40 cm, colonial from rhizome.  Leaves alternate; basal leaves 3-parted; central leaflet broadly egg-shaped to 8 cm long, 6.5 cm cm wide, margin irregularly toothed, stem leaves 2, more or less opposite, similar to basal, central leaflet to 10 cm long, 4.5 cm wide. Leaves last 10 […]
Cardamine Genus bitter-cress; toothwort Brassicaceae -   Cardamine Genus are herbs herbs, ours mostly rather small annuals, biennials or spring ephemerals, some colonial, mostly hairless.  Leaves alternate, ours pinnate to three-parted.  Flowers white (ours), petals and sepals 4 each, small, stamens, 6 or less, ovary inferior, linear, cylindrical.  Fruit becoming dry, a linear capsule divided into two longitudinal compartments by a membranous partition, tipped […]
Cardamine hirsuta hairy bitter-cress Brassicaceae CAHI*; Bx, pb (DeCandido 2001); NY, hb; R (DeCandido 2001); -    Cardamine hirsuta is an annual, winter annual herb, stem 10-40 cm tall, smooth. Name hirsuta is rather misleading since this plant looks hairless without a lens. Even then, hairs are sparse.  Leaves alternate, mostly in a dense basal rosette, pinnate, leaflets rounded, short-stalked, terminal leaflet larger, often lobed, stem leaves few, inconspicuous, becoming narrower towards top of […]
Cardamine parviflora small-flowered bitter cress Brassicaceae CAPA; Bx, pb (DeCandido 2001); -    Cardamine parviflora is an annual or biennial, stems mostly solitary, to 30 cm tall.  Leaves alternate, pinnate, to 4 cm long with 3-6 pairs of leaflets, leaflets of rosette leaves sparsely toothed.  Flowers white, 4-parted, petals to 0.3 cm long.  Fruit capsules to 3 cm long, less than 0.1 cm wide, seeds 26-46, less than 0.1 cm, […]
Cardamine pensylvanica Pennsylvania bitter-cress Brassicaceae CAPE; Bx, pb (DeCandido 2001); R (DeCandido 2001); -    Cardamine pensylvanica is an annual to biennial to 60 cm tall, stem hairy below.  Leaves alternate, pinnate, terminal leaflet rounded, to 2 cm wide, stem leaves to 8 cm long, leaflets oval, to 0.8 cm; basal leaves few to none.  Flowers white, 4-parted, petals to 0.4 cm long.  Fruit dry, capsules linear, to 3 cm long; blooming […]
Cardamine rhomboidea  (C. bulbosa) spring cress Brassicaceae CARH; Bx, pb; Q (DeCandido 2001); -    Cardamine rhomboidea is an annual or perennial to 45 cm, elongating as flowers and fruit develop to 60 cm, stems 1 to a few, from a short, stout rhizome.  Leaves alternate, simple, basal leaves round to heart-shaped about as wide as long, long-stalked, usually dying before plant flowers, stem leaves 4-8, rounded to narrow, the […]
Cardaria draba hoary cress Brassicaceae CADR*; Bx, pb (DeCandido 2001); R (DeCandido 2001); - Cardaria draba is a perennial herb to 60 cm tall, aggressively colonial from creeping rhizomes, stems erect, hairy below. Leaves alternate, stem leaves egg-shaped, base lobed, stalkless, clasping stem, to 9 cm long, 4 cm wide, basal leaves to 10 cm, stalked. Flowers white, 4-parted, to 0.4 cm; inflorescence branched. Fruit dry, capsules heart-kidney-shaped, to 0.3 cm long, […]
Carduus nutans musk-thistle Asteraceae CANU*; Bx, pb (DeCandido 2001); R (DeCandido 2001); -    Carduus nutans is a biennial herb, 30-150 cm tall, from a fleshy taproot, all parts very spiny.  Leaves of first year in a rosette, leaves of flowering stem alternate, to 25 cm long, 10 cm wide, elliptic to lance-shaped, deeply, irregularly lobed and toothed, waxy pale-green, spiny at lobe and tooth tips, leaf bases extending […]
Caulophyllum thalictroides blue cohosh Berberidaceae CATH; Bx, pb, wv (Yost et al. 1991); R, gb; -      Caulophyllum thalictroides is a perennial herb from a large root crown, root system large, perennial, associated with VA mycorrhizas (Brundrett and Kendrick 1988); stems and leaves waxy-pale (glaucous), a summer green herb (Hicks and Chabot 1985), however leaves tend to die off if no fruit is produced.  Leaves mostly one per stem, twice 3 […]
Centaurea cyanus cornflower; bachelor’s button Asteraceae CECY*; Q (DeCandido 2001); -      Centaurea cyanus is an annual or winter annual herb, 20-120 cm tall, young plants white-wooly.  Leaves alternate to 13 cm long x 1 cm. wide, linear, often white-wooly below, lower ones with a few teeth.  Flowers usually blue, all tubular but marginal flowers larger, ray-like, flower heads solitary at ends of branches, bracteate base of […]
Centaurea dubia  (C. nigrescens) short-fringed knapweed Asteraceae CEDU*; Bx, pb, vc; R (DeCandido 2001); -     Centaurea dubia  is a perennial herb, 20-80 cm tall, branched, finely hairy or webby when young.  Leaves alternate, stem leaves sessile, lance-shaped, entire or toothed, basal leaves stalked, sometimes lobed, 1.5-4 cm wide, much smaller above.  Flowers pale purple, all discoid, marginal flowers, enlarged, ray-like, with long, narrow petal lobes; flower heads terminal on branches, bracteate […]
Centaurea Genus knapweed Asteraceae -    Centaurea is a genus of herbs.  Leaves alternate (ours).  Flowers blue-purple to pink (ours), all disk flowers (discoid) with long petal lobes but often the marginal flowers larger and irregular; basal bracts in several, overlapping rows, dry, membranous, margins fringed or ragged, expanded top of flower stalk (receptacle) with dense bristles.  Fruit dry, 1-seeded (achenes), with or […]
Centaurea jacea brown knapweed  Asteraceae  CEJA*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); R (DeCandido 2001);  - Centaurea jacea is a perennial herb, 30-80 cm tall. Leaves of winter rosette stalked, variable, 1.5-4 cm wide, stem leaves alternate, lance-shaped, sometimes toothed or lobed, becoming smaller upward. Flowers pink-purple, all tubular, the outer ones longer, ray-like, bracteate base 1.2-1.8 cm long and wide, bracts wide, tips with brown, irregularly fringed appendage with a pale margin, […]
Centaurea maculosa spotted knapweed Asteraceae CEMA*; Bx, cn, pb, sn, vc; Q, dp, fr, i, j, t; K, fl, pl; R, lp; -     Centaurea maculosa is a biennial or short-lived perennial herb to 1.5 m tall, stems and leaves pale, gray-green, overwintering as a rosette, can resprout from root crown for several years and reproduce vegetatively from lateral shoots that emerge to form new rosettes; flowering plant much branched. Leaves alternate, deeply pinnately lobed, lobes narrow to linear, […]
Centaurea nigra black knapweed Asteraceae CENI*; Bx, pb (DeCandido 2001); R (DeCandido 2001); -     Centaurea nigra is a perennial  herb, 20-80 cm tall, very much like C. jacea, rough-hairy, young plant sometimes cobwebby.  Leaves alternate, leaves of winter rosette stalked, variable, 1.5-4 cm wide stem leaves alternate, lance-shaped, sometimes toothed or lobed, becoming smaller upward, the uppermost becoming small bracts.  Flowers pink-purple, all tubular, and about the same size, bracteate base […]
Cerastium arvense field chickweed Caryophyllaceae CEAR; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, j (Stalter and Lamont. 2002); K (DeCandido 2001); R, d; -     Cerastium arvense is a perennial herb, stems 15- 40 cm long, hairy to smooth, branched, often forming mat at base, flowering stems usually ascending.  Leaves opposite, linear to egg-shaped, 2-7 cm long, 1-1.5 cm wide, usually with small leafy tufts in axils.  Flowers white, petals 5, deeply 2-lobed, about 1cm long, 2-3 times as long as […]
Cerastium fontanum  (C. vulgatum) mouse-ear chickweed Caryophyllaceae CEVU*; Bx, pb; NY, bl (Stalter and Tang 2002); Q, j; K; R, d, e; -     Cerastium fontanum is a short-lived perennial, 15-50 cm long from fibrous roots, stems sprawling, hairy, slightly sticky, rooting at nodes, with short, matted basal branches.  Leaves opposite, stalkless (sessile), blade 1-2 cm long, 0.3-1.2 cm wide, stem leaves egg-shaped, lower leaves spatula-shaped, hairy, dark green.  Flowers white, to 0.6 cm wide, petals 5, deeply 2-lobed, to […]
Cerastium Genus chickweed Asteraceae -    Cerastium is a genus of low, small herbs.  Leaves opposite, generally small.  Flowers white, petals 5, free, widest near tip, narrowed at base, tip often notched, sepals 5 (in ours), stamens 10, styles 5, ovary superior.  Fruit dry, a capsule, mostly longer than sepals, cylindrical, thin-walled, splitting open at tip leaving 10 small teeth at opening; seeds […]
Cerastium semidecandrum mouse-ear chickweed Caryophyllaceae CESE*; Bx, pb; R; al; -    Cerastium semidecandrum is an annual herb, very hairy, slightly sticky, stems 5-20 cm long, branched from base or unbranched, slender.  Leaves opposite, 0.5-1.5 cm long, basal leaves widest near tip, stem leaves egg-shaped, very hairy, stalkless (sessile).  Flowers white, petals 5, slightly shorter than sepals, slightly notched at tip, sepals 5, 0.3-0.5 cm, glandular-hairy, narrow, pointed, […]
Cerastium viscosum  (C. glomeratum) clammy chickweed Caryophyllaceae  CEVI*; Bx, pb; NY, bl (Stalter and Tang 2002); R, hs, mls; - Cerastium viscosum is an annual or winter annual herb, 5-30 cm tall, sticky-hairy. Leaves opposite, stalkless, blade 1-2.5 long, 0.5-1.5 cm wide, hairy on both sides, egg-shaped, lower leaves spatula-shaped, tips rounded. Flowers white, petals deeply notched at tip, slightly shorter than to about as long as sepals, sepals to 0.5 cm, narrow, tip pointed, margins rather […]
Ceratophyllum demersum coontail; hornwort Ceratophyllaceae CEDE; Bx, pb; NY, ct; R, wp; - Ceratophyllum demersum is a submersed, rootless aquatic perennial herb, stems thin, long, branched, branches often modified into root-like rhizoids. Leaves in numerous whorls of 5-12, 1-3 cm long, to 0.1 cm wide, linear, somewhat stiff, usually forked once or twice into 2-4 segments, one side with sparse, back curved teeth. Flowers inconspicuous, sexes separate, axillary, males above […]
Ceratophyllum echinatum prickly hornwort Ceratophyllaceae CEEC; R (DeCandido 2001); -    Ceratophyllum echinatum is a submersed, rootless aquatic perennial herb, stems thin, long, branched, branches often modified into root-like rhizoids.  Leaves whorled, forked 3-4 times, ultimate leaf segments with fewer, or no teeth.  Flowers as above.  Fruit with warty surface and several unequal spines in addition to the basal ones.  Wetland status: OBL.  Frequency in NYC: Very infrequent  […]
Chaenorrhinum minus dwarf snapdragon Scrophulariaceae CHMI*; Bx, pb (DeCandido 2001); - Chaenorrhinum minus is an annual herb to 30 cm tall, glandular-hairy. Leaves alternate, linear, to 2 cm long, tip blunt, stalk very short.  Flowers blue-purple with yellow mark, irregular, to 0.6 cm long, axillary.  Fruit a dry capsule. Wetland status: UPL.  Frequency in NYC: Very infrequent.  Origin: European.  Habitat: Open areas, railway rights-of-way.
Chamaecrista fasciculata  (Cassia f.) partridge-pea Caesalpiniaceae CHFA; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R, c, gr, k, js, lp, t; -     Chamaecrista fasciculata is an annual herb, to 75 cm, stems hairy.  Leaves alternate, evenly pinnate, oblong with 10-18 pairs leaflets, 1-2 cm, linear-oblong, fine, sharp-tipped; cup-shaped gland at base stalkless, stipules persistent.  Flowers yellow, with red markings, slightly irregular, 5-parted, to 3 cm wide, petals slightly unequal, narrow at base, stamens 10, unequal, blooming and fruiting […]
Chamaecrista nictitans  (Cassia n.) wild sensitive plant Caesalpiniaceae CHNI; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); R, ty; -     Chamaecrista nictitans is an annual herb, 30-50 cm tall.  Leaves alternate, evenly pinnate, leaflets 7-20 pairs, oblong, 0.6-1.5 cm, bristle-tipped, finer than those of C. fasciculata, gland at leaf base short-stalked, leaflets fold together when disturbed (Newcomb 1977).  Flowers yellow, somewhat irregular, to 0.8 cm wide, petals very unequal, one almost twice as long as others, stamens […]
Chamaesyce maculata  (Euphorbia m.) eyebane, spotted sandmat Euphorbiaceae EUMA2; Bx, cm, fl, pb, sn, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, mn; Q, ft, i, j, tl; K, fs, pl; R, hs, wp; -      Chamaesyce maculata is an annual C4 herb (Downton 1971), prostrate, mat forming, stems often pink, to 40 cm long, usually finely hairy, sap milky.  Leaves opposite, dark gray-green usually with reddish or dark spot, oblong 0.5-1.5 cm, widest below middle, no stalk.  Flowers tiny, inconspicuous, monoecious, but males and females grouped together, axillary (use lens), stamen […]
Chamaesyce nutans (Euphorbia n., E. preslii) eyebane Euphorbiaceae EUNU; R (DeCandido 2001); -     Chamaesyce nutans is an annual herb to 80 cm, more or less erect, young parts finely hairy; sap milky, acrid. Stems often  pinkish.  Leaves opposite, oblong 1-3.5 cm long, about 0.3-1 cm wide, sides usually unequal, margin finely toothed.  Flowers tiny, inconspicuous, monoecious, but males and females grouped together, axillary (use lens), stamen one, pistil one, […]
Chamaesyce polygonifolia  (Euphorbia p.) seaside spurge Euphorbiaceae EUPO; Bx, pb (DeCandido 2001); Q, j, rb; R, c; -     Chamaesyce polygonifolia is an annual herb (Duncan and Duncan 1987), mat forming, prostrate to ascending, hairless, sap milky, poisonous, stems to 25 cm long, often pink or red, branches forking, rooting at nodes, propagating vegetatively if broken (Silberhorn 1982).  Leaves opposite, 08.-1.5 cm long, linear to lance-shaped, pale matte gray-green, margin entire, base slightly unequal.  […]
Chelidonium majus celandine Papaveraceae CHMA*; Bx, br, pb, sd, sf, wv (Yost et al. 1991); NY, iw; Q (DeCandido 2001); K, p; R, cg, cl, lp, mls; -     Chelidonium majus is a biennial herb to 80 cm tall, branched, pale, somewhat blue-green, very hairy, sap bright orange, sticky, very toxic if ingested, contains a number of alkaloids common to Papaveraceae including chelidonine, sanguinarine, and berberine (Kingsbury 1964).  Leaves alternate, deeply pinnately lobed to compound, hairy below, blunt toothed, from an overwintering rosette, new […]
Chelone glabra turtlehead Scrophulariaceae CHGL; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002); R, gb, t; (also often planted in wetland restorations and mitigations). -     Chelone glabra is a perennial herb, usually unbranched, to 80 or more cm tall, erect, stem square.  Leaves opposite, lance-shaped to linear, to 15 cm long, margin toothed, stalk short or none.  Flowers white to pink-tinged, bilaterally symmetric, oblong, hooded, to 3.5 cm long, above 2-3 bracts, inflorescence of spikes to 8 cm long, blooming July- […]
Chenopodium album lamb’s quarters; pigweed Chenopodiaceae CHAL*; Bx, br, bz, ht, pb, sd, sf, sn, up, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw, rr; Q, cu, f, ft, i, j, lk; K, do, fl, fs, m, p, pl; R, a, ar, bk, bm, c, cs, fk, hs, js, lc, sv; -     Chenopodium album is an annual, C3 herb (Jacobs 2001), erect, about 1m (occasionally to 2.5 m), branched, stem angular pale green, ridged with reddish or pale stripes.  Leaves alternate, stalked, blade 3-10 cm long, to 8 cm wide, egg- to diamond-shaped, upper leaves often lance-shaped, tip pointed to blunt, base broadly, shallowly wedge-shaped, major veins 3, […]
Chenopodium ambrosioides Mexican tea; wormseed Chenopodiaceae CHAM*; Bx, br, bz, pb, sd; NY, bl (Stalter and Tang 2002), hb, mn, n, rr; Q, a, f, j; K, p; R, c, hs; -     Chenopodium ambrosioides is an annual C3 herb (Jacobs 2001), to short-perennial from a long fleshy taproot; unpleasantly aromatic, stem to 1 m, finely ribbed, erect, usually hairless but often white waxy-mealy, often much branched.  Leaves narrowly egg-shaped, to 12 cm long, with large regular teeth, pointed at both ends, dotted with tiny translucent glands below (use […]
Chenopodium botrys Jerusalem-oak; feather geranium Chenopodiaceae CHBO*; NY, mn; R (DeCandido 2001); -     Chenopodium botrys is an annual C3 herb (Jacobs 2001), to 60 cm, glandular-hairy, sticky, strongly aromatic.  Leaves alternate, pinnately lobed or divided, lobes blunt-toothed, lower leaves to 8 cm long, upper leaves much smaller.  Flowers minute, dull, calyx deeply 5-lobed, glandular-hairy, inflorescence sender branched.  Fruit dry, 1-seeded, seeds mostly horizontal 0.6-0.8 cm blackish, no margin; blooming and fruiting […]
Chenopodium capitatum strawberry-blite Chenopodiaceae CHCA; R, bm, c; -      Chenopodium capitatum is an annual, C3 herb (Jacobs 2001), 20-60 cm tall, branched from base.  Leaves alternate, stalks of lower leaves longer than blade, upper stalks shorter, blade triangular to arrow-shaped, to 10 cm long, margin toothed.  Flowers minute, red in small rounded clusters.  Fruit dry, 1-seeded, surrounded by fleshy, red calyx.  Wetland status: UPL.  Frequency […]
Chenopodium Genus goose-foot; blite Chenopodiaceae -   Chenopodium is a genus  of herbs.  Leaves alternate, no stipules.  Flowers green to reddish, radially symmetrical, very small, no petals, calyx usually 3-5 parted, lobes mostly blunt, curved over superior ovary, stamens same number as sepals; inflorescence mostly of small, headlike flower clusters, in spikelike or branched arrangements.  Fruit dry, thin-walled, 1-seeded, surrounded by persistent calyx.
Chenopodium glaucum oak-leaf goosefoot Chenopodiaceae CHGL*; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R(DeCandido 2001); -      Chenopodium glaucum is an annual, C3 herb (Jacobs 2001), 10-40 cm tall, branched from base, stems whitish-mealy.  Leaves alternate, lower leafstalks much longer than blades, upper leaf stalks much shorter; blade oblong to egg-shaped, 1-4 cm long, base wedge-shaped, green above, whitish-mealy below, entire to pinnately blunt toothed with 2-4 teeth per side.  Flowers minute, […]
Chenopodium rubrum coast blite Chenopodiaceae CHRU; R (DeCandido 2001); - Chenopodium rubrum is an annual C3 herb (Jacobs 2001), branched from base, prostrate to erect, ca 40 cm tall (NYS Rare plant status: S2 T). Leaves alternate, ca 6 cm long, egg-shaped, surface often tinged with red, base wedge-shaped, margin with a few broad teeth, becoming red late in season. Flowers tiny, green tinged with red, all […]
Chenopodium simplex  (C. gigantospermum) maple-leaf goosefoot Chenopodiaceae CHGI; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R (DeCandido 2001); -     Chenopodium simplex is an annual C3 herb (Jacobs 2001), to 1.5 m tall, erect, bright green.  Leaves alternate, stalk elongate, blade broadly egg-shaped to deltoid, 5-20 cm long, with 1-4 large lobe-like teeth per side, tip pointed, base blunt to lobed.  Flowers minute; inflorescence terminal, branched, of spikes.  Fruit to 0.2 cm, seeds horizontal, shiny, black (Stalter […]
Chenopodium urbicum city goosefoot Chenopodiaceae CHUR*; Bx, pb (DeCandido 2001), wv (Yost et al. 1991) (Yost et al. 1991); NY (DeCandido 2001); K (DeCandido 2001); R (DeCandido 2001); -    Chenopodium urbicum is an annual, C3 herb (Jacobs 2001), 0.3-1 m tall, erect, branches divergent from base to apex.  Leaves alternate, to 8 cm long, 5 cm wide, rhombic- to egg-shaped or triangular, tip pointed, base truncate, margins coarsely toothed, bright green, shiny above, white-mealy below, at least when young.  Flowers minute, calyx 5-parted, lobes rounded on […]
Chimaphila maculata spotted wintergreen Pyrolaceae CHMA2; Bx, pb; R, ah, ap (E. Danielsen 4/2017), ar, bd, cl, cp, gb, h, jw, lp, lt, k, r, ro, sm, sv, wp; -     Chimaphila maculata is a perennial, evergreen, slightly woody (subshrub), stems reddish, colonial from a creeping rhizome, roots associated with specialized mycorrhizal fungi (Smith and Read 1997); flowering stem 10-20 cm tall.  Leaves alternate, appearing whorled, stalk short, blade 2-7 cm long, stiff, tip pointed, base rounded, surface dark, blue-green, midrib and larger lateral veins white, […]
Chrysanthemum leucanthemum  (Leucanthemum vulgare) ox-eye daisy Asteraceae CHLE*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, j (Stalter and Lamont. 2002); K (DeCandido 2001); R, fk, js, lp, mm; -     Chrysanthemum leucanthemum is a short-lived perennial from rhizomes, vegetative reproduction slow from rhizomes, roots infected with vesicular-arbuscular mycorrhizae (Clements et al. 2004a); stems 20-80 cm tall, clumped, simple or sparsely branched, usually hairless.  Leaves alternate, 4-15 cm long, narrow, margin lobed or with long, blunt teeth, overwintering leaves of basal rosette more spatula-shaped, widest toward […]
Cichorium intybus chicory Asteraceae CIIN*; Bx, br, pb, vc, sf, wv (Yost et al. 1991); NY, ct, wr; Q, a, f, ft, j; K, fs, pl, p; R, cs, e, is, js, k, mm, sv, ty, w; -     Cichorium intybus is a short-lived perennial 30-170 cm tall, from a long taproot, sap milky, flowering stems slender, hollow, usually branched.  Leaves alternate, pinnately divided, those of winter rosette much like dandelion leaves, stalked, blade 8-25 cm long, 1-7 cm wide, somewhat rough textured and hairy, widest above the middle, stem leaves stalkless, becoming reduced […]
Cicuta maculata water hemlock Apiaceae CIMA; Bx, pb, sf; R, h; -     Cicuta maculata is a perennial herb to 2 m tall, sap yellowish, pungent (similar to parsnip). Roots clustered, tuberous, roots gradually consumed by growth, flowering and fruiting, but producing an overwintering, perenniating shoot before end of season; rootstock at base of stem, stout, hollow, with diaphrams of pith (Kingsbury 1964), often mottled with purple, […]
Cimicifuga racemosa  (Actaea r.) black snakeroot, black bugbane Ranunculaceae CIRA; Bx, pb, vc, wv (Yost et al. 1991); NY (DeCandido 2001); Q, cu (Greller 1977, 1979, 1985); R (DeCandido 2001); -     Cimicifuga racemosa is a perennial herb, 1-2.5 m tall, from a knotty rhizome.  Leaves alternate, 3-parted, each segment pinnately once or twice compound, leaflets toothed, lobed, 3-10 cm long.  Flowers white, small, sepals 5, to 0.5 cm long, no petals, stamens white, numerous to 1 cm long; inflorescence 20-80 cm long, branched; blooms Aug.-Sept..  Fruit dry, narrow […]
Circaea lutetiana  (C. quadrisulcata) enchanter’s nightshade Onagraceae CILU; Bx, bg, br, cf, pb, sf, up, vc, wv (Yost et al. 1991); NY, iw; Q, a, cu, f; K, p; R, bd, c, cg, cl, gb, wt; -     Circaea lutetiana is a perennial herb, to 70 cm tall, extensively colonial from rhizomes, roots associated with VA mycorrhizas, roots produced from rhizomes as new aerial shoots emerge in late spring (Brundrett and Kendrick 1988).  Leaves opposite, each pair at right angles to next, blade egg-shaped, 6-12 cm long, tip long-pointed, base rounded or slightly […]
Cirsium arvense Canada thistle Asteraceae CIAR2*p; Bx, br, pb, vc; NY, bl (Stalter and Tang 2002); Q, ft, i, j, lk, wl; K, p; R, c, cl, cs, fk, hs, v, wp; -     Cirsium arvense is a perennial herb, 30-150 cm tall, leafy, spiny, aggressively colonial from deep, creeping roots, root depths of over 6 m reported, can regenerate from root segments, however individual roots only live for about 2 years; horizontal roots may grow 6 m per season, emerges in mid-April, minimum root reserves occur in […]
Cirsium discolor field thistle Asteraceae CIDI; Bx, pb (DeCandido 2001; R, c, ml (Z. Wang); -    Cirsium discolor spiny biennial or perennial, herb, second year stem 1-2 m tall, branching near top, usually hairy but not wooly, finely ribbed but not winged.  Leaves alternate, stalked, those of first year a rosette, blades to 50 cm long, 20 cm wide, stem leaves becoming progressively smaller above, stalkless, numerous deeply pinnately lobed, lobes spine-tipped, […]
Cirsium Genus thistle Asteraceae -    Cirsium  is a genus of spiny herbs.  Leaves pinnately lobed to toothed, lobes spine-tipped.  Flowers mostly purple, sometimes yellow or white, all disk flowers, radially symmetrical, tubular, in heads with bract-covered base, bracts mostly spine-tipped, overlapping in several rows, expanded apex of flower stalk (receptacle) bristly.  Fruit a dry 1-seeded achene, with bristly plume for wind dispersal. […]
Cirsium horridulum yellow thistle Asteraceae CIHO; Bx, pb (DeCandido 2001; K (DeCandido 2001; R (DeCandido 2001; -     Cirsium horridulum is a biennial herb, 0.2-1.5 m tall, stems stout, webby-hairy when young, often unbranched.  Leaves alternate, very spiny, pinnately divided, margin very spiny, usually broad, base clasping stem, first year rosette leaves hairy above, wooly-hairy below.  Flowers pale yellowish or purple, all tubular, base of flower head 3-5 cm long, outer bracts pinnate-spiny and […]
Cirsium muticum swamp thistle Asteraceae CIMU; R (DeCandido 2001); -     Cirsium muticum is a coarse biennial herb, 0.5-2 m tall from branched roots, stems branching, soft, hollow, young stems webby-hairy.  Leaves alternate, basal rosette leaves stalked, stem leaves stalkless, blade to 55 cm long, 20 cm wide, pinnately lobed and toothed, thin, often pale webby-hairy below, margin weakly spiny.  Flowers pink to purple, all tubular, in […]
Cirsium pumilum pasture thistle Asteraceae CIPU; Q (DeCandido 2001); K, p; -     Cirsium pumilum is a biennial herb, 30-80 cm tall, from a deep taproot, stems stout.  Leaves alternate, first year rosette leaves numerous, short-stalked, blades 12-25 cm long, 2-7 cm wide, widest above middle, pinnately divided, margins prickly, green on both sides, stem leaves lance-shaped, shallowly lobed and toothed, very prickly, reduced upwards.  Flowers purple, fragrant, tubular, […]
Cirsium vulgare bull thistle Asteraceae CIVU*; Bx, pb, wv (Yost et al. 1991); NY (DeCandido 2001); Q, cu (Greller 1977, 1979, 1985), j (Stalter and Lamont. 2002); K, p; R, cl, cs; pr, sv, ty, wp; -     Cirsium vulgare is a biennial herb, to 50-150 cm tall, very hairy, stem spiny-winged from extended leaf bases, deeply taprooted.  Leaves alternate, narrow, about 15 cm long, 5 cm wide but very variable, very spiny with irregular spine-tipped, toothed lobes, both sides hairy, first years leaves in an overwintering rosette.  Flowers purple, all tubular, to 4 […]
Claytonia virginica spring beauty Portulacaceae CLVI; Bx, bg, br, pb, vc, wv (Yost et al. 1991); NY (DeCandido 2001); K, p; R, an, bd, cr (U. Lorimer 2017), gb, w, wp; -    Claytonia virginica is a perennial, spring ephemeral herb; about 10 cm tall from a corm (storage root) about 3 cm thick, bearing several flowering stems, colonial by vegetative reproduction of corms.  Leaves linear, stalkless, fleshy, dying back by late May; a single vegetative leaf and two basal leaves on each flowering stem.  Flowers pinkish-white, 5 petals; […]
Cleome hassleriana spider flower Capparaceae CLHA*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); K (DeCandido 2001); R (DeCandido 2001); -    Cleome hassleriana is an annual herb to 1.5 m tall, stem stout, sticky-hairy, branched above.  Leaves alternate, palmately compound, leaflets 5-7, narrow, widest above middle, finely hairy, central leaflet to 10 cm long, leaf stalk with pair of spines at base.  Flowers white to pink, petals to 1 cm, all on one side, narrowed at base, […]
Clinopodium vulgare  (Satureja vulgaris) wild basil Lamiaceae SAVU*; R, cp, mm; - Clinopodium vulgare is a perennial herb, from short stolons, rooting at nodes, upper stem erect to 50 cm tall, very hairy, square.  Leaves opposite, egg to lance-shaped, to 4 cm long, hairy, margin entire to slightly toothed, stalk to 1 cm upper leaves often stalkless; inflorescence head-like at ends of stems, sometimes in upper axils of […]
Collinsonia canadensis horse balm; stoneroot Lamiaceae COCA; Bx, pb, vc; Q, cu, f; R, h, t; -     Collinsonia canadensis is a perennial, colonial herb from a woody rhizome, erect, to about 1 m tall, branched above.  Leaves opposite, in several pairs, stalk to 10 cm, blade 10-20 cm long, becoming smaller and sessile upward, egg-shaped, tip long-pointed, margin toothed, aromatic-lemon scented when crushed.  Flowers pale yellow, small, fragrant, tubular, bilaterally symmetric, one lobe […]
Comandra umbellata bastard toad-flax Santalaceae  COUM; Q, j (Stalter and Lamont. 2002); R lp; -    Comandra umbellata is a perennial, partial root parasite (hemiparasite) to 40 cm tall, stems leafy, mostly unbranched, colonial from rhizomes.  Leaves alternate, oblong, to 5 cm long, conspicuously net-veined, thin, pale below.  Flowers small, greenish-white, calyx 5-parted, bell-shaped, lobes 0.3 cm, no petals (Newcomb 1977), in branched clusters, blooms May-June.  Fruit dry, to 0.6 cm wide.  Wetland status: […]
Commelina communis Asiatic dayflower Commelinaceae COCO2*; Bx, bg, br, pb, sf, up, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw; Q, a, cu, j; K, p; R, ar, c, cl, d, hs, sv, ty, wt; -   Commelina communis is an Annual monocotyledon, trailing herb, rooting at nodes stems to 80 cm long, succulent, pale green.  Leaves alternate, stalkless, basal sheath 1-2 cm, clasping stem, blade narrowly egg-shaped, 5-12 cm long, 1.5-4 cm wide, tip pointed, base slightly lobed.  Flowers bilaterally symmetrical, 3 petals, the upper two blue, 0.8-1.5 cm long, the lower […]
Conium maculatum poison hemlock Apiaceae COMA*; Bx br, pb; NY ct; R gb; -     Conium maculatum is a biennial herb to 3 m tall, from a white, fleshy taproot, very poisonous, with a distinctive, unpleasant, “mousey” odor; stem stout, stiff, hollow between nodes, freely branched, purple-spotted.  Leaves alternate, to 40 cm long, 3-4 times pinnate, broadly triangular in outline, much dissected, fern-like, ultimate segments to 1 cm, egg-shaped, margins toothed […]
Conopholis americana American cancer-root Orobanchaceae COAM; Q (DeCandido 2001); R; (DeCandido 2001) possibly historic. -     Conopholis americana is a herbaceous root parasite of some oak species. Entire plant yellowish or pale brown (no chlorophyll), 5-20 cm tall, erect, unbranched, stem stout, covered by leaf scales, often forming rounded knobs on tree roots, resembling old cones of white pine.  Leaves reduced to scales, to 2 cm long, fleshy, egg-shaped.  Flowers very irregular, […]
Convallaria majalis lily-of-the-valley Liliaceae COMA2*p; Bx, br, vc; R, bm, c, cb, cg, gr, js, lp, t; -     Convallaria majalis is a perennial monocotyledon to 20 cm tall, extensively colonial, from rhizomes.  Leaves about 10 cm, elliptic, entire, dull blue-green.  Flowers white, radially symmetrical, bell-shaped, petals fused into a round base with short, flaring lobes, very fragrant, 0.6-0.9 cm wide, dangling in a row from a curved stem.  Fruit fleshy, red, 1 cm wide, seeds […]
Conyza canadensis  (Erigeron c.) horseweed Asteraceae COCA2; Bx, br, cn, ht, pb, sn, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, rr, wr; Q, fr, i, j; K, fl, fs, m, p, pl; R, c, hs, k, pr, sv, wp; -    Conyza canadensis is an annual or winter annual C3 herb (Ludwig et al. 2010), roots found to be associated with mycorrhizal fungi (Weaver 2001), stem 1-1.5 m tall, hairy, unbranched below inflorescence.  Leaves alternate, to 8 cm long, 0.8 cm wide cm, numerous, closely spiraled around stem, reduced upwards to 0.5 cm wide, sometimes appearing opposite […]
Coreopsis lanceolata lance-leaf tickseed Asteraceae COLA*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont. 2002), tl; K (DeCandido 2001; R (DeCandido 2001); -     Coreopsis lanceolata is a perennial herb to 60 cm tall, stems clustered, leafy below, naked above.  Leaves opposite, lower leaves spatula-shaped to linear, to 20 cm long, 2 cm wide, often with 1-2 pairs of lateral lobes, upper leaves smaller, stalkless.  Flowers yellow, rays to 3 cm long, disk to 2 cm wide, basal bracts in […]
Coreopsis major forest coreopsis Asteraceae COMA*; R (DeCandido 2001); -    Coreopsis major is a perennial herb, 50-100 cm tall, from rhizomes but stems usually tufted, hairy.  Leaves opposite, 3-parted, stalkless, leaflets 3-8 cm long, 1-3 cm wide, upper leaves sometime undivided.  Flowers yellow, ray flowers 1-2.5 cm long, disk 0.7-1.5 cm wide, flowers yellow becoming red or purple, outer bracts of flower head base 8, bristly-hairy, […]
Coronilla varia crown-vetch Fabaceae COVA*; Bx, pb, sd; NY, hb; K, fs, pl; Q, j (Stalter and Lamont. 2002); R, c, v; -     Coronilla varia is a perennial, vining, sprawling ground cover 3-10 m long, stems finely but strongly ribbed, branched.  Leaves alternate, pinnate, 6-15 cm, leaflets 11-25, oblong, 1-2 cm long, nearly sessile, dull, dark green, oblong, tip rounded to notched, base rounded.  Flowers pink and white, bilaterally symmetric, pea-flower-shaped, ca 1 cm long, in dense radiating, crown-shaped […]
Coronopus didymus  (Coronopsis didymus) wart-cress Brassicaceae CODI* NY, ct (M. Feder p.c.); Q, fh (M. Feder p.c.); -     Coronopus didymus is an annual or biennial, fetid smelling herb 10-40 cm tall, forming mats to 80 cm wide, stems much branched, ascending to spreading.  Leaves alternate pinnately divided, 1-3 cm long, oblong, segments entire to deeply few-toothed.  Flowers white, very small, radially symmetrical, petals spatula-shaped, only slightly longer than sepals.  Fruit becoming dry, to 0.3 cm […]
Corydalis incisa corydalis Fumariaceae COIN* Bx, br; - Corydalis incisa is a biennial, spring ephemeral, 10 to 50 cm tall, branched, hairless, sap watery, initially from a spindle-shaped tuber (fusiform) about 1.2 cm long, 0.5 cm wide, roots becoming fibrous in the second year. Leaves alternate, numerous, stalk 5-20 cm long, blade 4-12 cm long and broad, fern-like, divided several times (ternate, bi […]
Crepis capillaris smooth hawk’s beard Asteraceae CRCA*; Bx, vc; -     Crepis capillaris is an annual or biennial herb, to 90 cm from a taproot, sap slightly milky, stem often freely branched, stem rough-hairy near base, plant sometimes pale, waxy-green.  Leaves alternate, mostly basal, to 30 cm long, 4.5 cm wide, basal leaves stalked, lance-shaped, toothed to deeply lobed, lobes pointed, stems leaves becoming smaller upwards, […]
Crocus vernus Dutch crocus Iridaceae CRVE*; Bx, pb, rd; NY, ct; -    Crocus vernus is a perennial monocotyledon, spring ephemeral, about 10 cm tall, from corms, colonial from corm offsets.  Leaves linear, stiffly erect (until senescence), with a prominent white midrib.  Flowers white to dark purple or white with fine purple stripes, anthers lemon-yellow, stigma red-orange, petal tube, narrow at base, surrounded by a single white bract, petal […]
Crotalaria sagittalis rattlebox Fabaceae CRSA; R (DeCandido 2001); -     Crotalaria sagittalis is an annual herb to 40 cm tall, hairy.  Leaves alternate, simple, to 8 cm long, 1.5 cm wide, linear to lance-shaped, hairy on both sides; stipules arrow-shaped, extending down stem from leaf base (Newcomb 1977).  Flowers yellow to 1.2 cm, pea-flower-shaped, calyx hairy to 0.9 cm, in unbranched clusters of 2-4, in axils, […]
Cryptotaenia canadensis Canada honewort Apiaceae CRCA; Bx, br, pb, rd, wv (Yost et al. 1991); NY ct; K, p; R, c, d, bd, gb, h, w; -     Cryptotaenia canadensis is a perennial herb to 1 m tall; roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); stem hairless, shiny, unbranched below inflorescence.  Leaves alternate, 3-parted, coarsely, irregularly toothed, often lobed as well, petiole expanded, leaflets 4-15 cm long, lower leaves long-stalked, the upper on short, dilated stalks.  Flowers white, radially symmetrical, very small; […]
Cuphea viscosissima blue wax-weed Lythraceae CUVI; Q, j (Stalter and Lamont. 2002); -     Cuphea viscosissima is an annual herb 15-60 cm tall , stem woody, sparsely branched, all parts sticky-hairy.  Leaves opposite, egg to lance-shaped, 2-5 cm long, long-stalked.  Flowers red-purple, 6-parted, irregular with a sticky-hairy tubular base to 1 cm long, 1-2 in upper axils, petals narrowed at base, largest ones 0.8 cm, blooms July-Sept.  Fruit dry, a capsule, […]
Cycloloma atriplicifolium winged pigweed Chenopodiaceae CYAT*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, i, j, rb; K, m, pl; R, c, lc, cp, sb, x;  -     Cycloloma atriplicifolium is an annual, C3 herb (Jacobs 2001), a tumble-weed, 10-80 cm tall, much branched, young plants hairy.  Leaves alternate, lower blades to 8 cm long, reduced above, pale gray-green, lance-shaped, margin with shallow, pointed lobes or large teeth, soon deciduous.  Flowers green, tiny, styles 3 (usually), calyx 5-lobed, lobes keeled, persistent, curving over and surrounding […]
Cymbalaria muralis Kenilworth-ivy Scrophulariaceae CYMU*; Bx pb (DeCandido 2001); NY, iw;  -    Cymbalaria muralis| is an annual trailing herb 10-40 cm long, rooting at nodes.  Leaves alternate, palmately 3-7 lobed, stalks elongate.  Flowers blue with yellow markings, bilaterally symmetrical, 0.7-1 cm long, 5-parted, two-lipped; May-Oct.. Fruit dry, round, 0.4 cm wide, splitting open to release seeds.  Wetland status: UPL.  Frequency in NYC: Very infrequent.  Origin: Eurasia.  Habitat: Roadsides, open […]
Cypripedium acaule pink lady’s slipper  Orchidaceae CYAC; Q, cu; R, cb, ev, ro; -   Cypripedium acaule is a perennial monocotyledon, flowering stem 20-40 cm tall, from a rhizome with clusters of fibrous roots (Rook 2004).  Leaves basal, elliptic, usually 2, pleated by parallel, impressed veins, 10-20 cm long, 8-15 cm wide, dull green, sparsely hairy, pale below.  Flowers bright pink, bilaterally symmetrical, fused lower petals (lip) 3-6 cm long, bag-shaped, […]
Datura stramonium jimsonweed Solanaceae DAST*; Bx, nb, pb, sf, wv (Yost et al. 1991); NY, ct, mn; Q, j; K; R, ar, c, fk, gk, hs, js; -     Datura stramonium is a summer annual, coarse, to 1.5 m (usually less), often branched.  Leaves alternate, stalk to 12 cm long, blade to 25 cm long, 25 cm wide, broadly ovate to elliptical, margin, irregularly few-toothed to shallowly lobed.  Flowers white or purple, radially symmetrical, showy, trumpet-shaped tubular, to 10 cm long, shallowly 5-lobed, lobes pointed, […]
Daucus carota Queen Ann’s lace Apiaceae DACA*; Bx, cm, ht, pb, sf, sn, vc, vc; NY, bl (Stalter and Tang 2002), ct, iw, wr; Q, a, dp, f, fr, ft, i, j, rb, ri, rw, tl, wl; K, do, fl, fs, p, pl; R, bm, c, ca, cl, cs, e, fk, gb, is, jl, js, jw, k, lp, mc, mls, pr, ro, sb, se, sv, t, ty, v, w; -    Daucus carota is a biennial, sometimes annual to short-lived perennial herb, from a large taproot, (same species as cultivated carrot), flowering stems to 1 m second year, grooved, hairy; crushed plant with carrot odor.  Leaves alternate, pinnate, finely divided, ultimate segments linear to oblong.  Flowers white, radially symmetrical, 5-parted, small; inflorescence umbrella-shaped, compound, 4-12 cm wide, […]
Decodon verticillatus swamp-loosestrife; water willow Lythraceae DEVE; Q, a, cu; R, ar, h, gb, h, is, lp, ml, t; -     Decodon verticillatus is a perennial herb from woody base, bark of submerged stems thick, spongy; stems slender 1-3 m long, arching, 4-angled, rooting at tips, extensively colonial.  Leaves whorls of 3-4, sometimes opposite, petiole short, blade 5-15 cm long, 1-4 cm wide, lance-shaped.  Flowers pink-purple, radially symmetrical, 4-5 parted, petals 1-1.5 cm, long, narrowed at base, […]
Desmodium canadense showy tick-trefoil Fabaceae DECA; Bx, pb, vc; R, k; -     Desmodium canadense is a perennial herb, to 2 m tall, one to several stems, from a brown root, aerial stem branched above, finely hairy above; stipules 0.5-0.9 cm long.  Leaves alternate, 3-parted, leaf stalk 0.2-2 cm long, stipules of leaflets 0.2-0.4 cm long, leaflet stalks (petiolules) 0.2-0.3 cm long, central leaflet 5-10 cm long, 2-3.8 […]
Desmodium canescens hoary tick-trefoil Fabaceae DECA2; Bx, pb (DeCandido 2001), vc; R (DeCandido 2001); - Desmodium canescens is a perennial herb, 0.6-1.5 m tall, from a brown taproot, aerial stem much branched, hairy, hairs with hooked tips (use lens); stipules persistent, asymmetrically egg-shaped, 0.6-1.2 cm long, tip pointed. Leaves alternate, 3-parted, terminal leaflet to 5-13 cm long, 3-10 cm wide, much longer than stalk of terminal leaflet, leaflets broadly egg-shaped, tip […]
Desmodium cuspidatum big tick trefoil Fabaceae DECU; Bx, pb (DeCandido 2001); -     Desmodium cuspidatum is a perennial herb to 2 m tall, stem stout; stipules lance-shaped, to 1.7 cm long.  Leaves alternate, 3-parted, leaf stalk to 8 cm long, terminal leaflet to 14 cm long, 6 cm wide, egg-shaped, tip sharply long-pointed, lateral leaflets narrower, bright green above waxy-pale below.  Flowers pink, pea-flower-shaped, to 0.8 cm; blooms July-Aug.  […]
Desmodium Genus tick-trefoil Fabaceae -    Desmodium is a genus of perennial herbs, stipules present.  Leaves alternate, stalked, 3-parted.  Flowers pink to purple, occasionally white, bilaterally symmetrical, bean-flower shaped, 5-parted, upper petal the largest (standard) 2-lobed, rounded to egg-shaped, lateral petals (wings) smaller, two basal petals fused to form the keel that surrounds the 10 stamen, 9 stamens fused around single stigma, […]
Desmodium glutinosum pointed-leaved tick trefoil Fabaceae DEGL; Bx, pb (DeCandido 2001); R (DeCandido 2001); -      Desmodium glutinosum is a perennial herb, 10-40 cm tall, stems erect, solitary.  Leaves alternate, 3-parted, whorled at base of inflorescence, leaflets asymmetric, terminal leaflet 7-15 cm long, 6-12 cm wide, broadly egg-shaped, tip long-pointed, lateral leaflets narrower, stipules narrow, 0.1-1.0 cm long, persistent.  Flowers purple, pea-flower-shaped, to 0.8 cm long, on short, stout stalks; inflorescence […]
Desmodium nudiflorum naked-flowered tick trefoil Fabaceae DENU; Bx, pb (DeCandido 2001); Q, cu (Greller 1977, 1979, 1985);  -    Desmodium nudiflorum is a perennial herb living 10 years or more, mostly solitary (Bierzychudek 1982), stem forked at base one stem sterile, to 30 cm, leaves spiraled at top; the other stem flowering to 1 m, usually leafless.  Leaves alternate, 3-parted, leaflets egg-shaped, terminal leaflet 4-10 cm long, to 8 cm wide, finely hairy both […]
Desmodium paniculatum panicled tick trefoil Fabaceae DEPA; Bx, pb, vc; Q, cu (Greller 1977, 1979, 1985); R, ca, cl, gb, is, sv, ty; -     Desmodium paniculatum is a perennial herb, slender, erect, 0.6-1.2 m tall, often several stems from the root crown, branched above, nearly hairless, stipules narrow, 0.4-0.6 cm long, soon deciduous.  Leaves alternate, 3-parted, leaf stalk 2-5 cm long, leaflets thin, the terminal one 4-10 cm long, 1-2 cm wide, lateral leaflets smaller, oblong to lance-shaped, tip […]
Dianthus armeria Deptford pink Caryophyllaceae DIAR*; Bx, pb (DeCandido 2001); NY, rw; Q, j, tl; K (DeCandido 2001); R, c, cl, h, jl, mls, mm, ro; -    Dianthus armeria is an annual or biennial herb, 20-60 cm tall, slender, stiffly few-branched, nodes swollen.  Leaves opposite lance-shaped, basal leaves numerous, stem leaves 5-10 pairs, 3-8 cm long, 0.2-0.8 cm wide, stalkless, base clasping stem, finely hairy.  Flowers dark pink, finely dotted with white, radially symmetrical, 5-parted, petals elliptic, 0.5 cm long, narrowed at base, […]
Dicentra cucullaria Dutchman’s breeches Fumariaceae DICU; Bx, pb, rd, vc (Zihao Wang 2016), wv (Yost et al. 1991); NY, iw;  -     Dicentra cucullaria is a perennial, ca 10 cm tall; spring ephemeral; vegetative reproduction from short rhizome covered by small tear-shaped bulblets, often red, showing above soil.  Leaves basal from bulb, stalks elongate, often pinkish, 2 per flowering stem, more or less three-parted, splitting into many narrow segments, surface dull blue-green, underside silvery; appearing March-April, dying […]
Dicentra eximia wild bleeding heart Fumariaceae DIEX *; R, ah, lp; -     Dicentra eximia is a perennial herb about 30 cm tall; clumps spreading from a short, stout rhizome.  Leaves basal, dissected, segments toothed, pale bluish green, smooth; infl ca 40cm.  Flowers pink, bilaterally symmetrical, ca 2 cm, nodding, more-or-less heart-shaped, , May-April.  Fruit a narrow capsule with several seeds; seeds with white fleshy attachment (aril), probably ant dispersed.  Wetland […]
Diodia teres poorjoe; buttonweed Rubiaceae DITE; Bx, pb (DeCandido 2001); Q, i, j; R, cp; -      Diodia teres is an annual herb from a taproot, often sprawling, stems 20-80 cm long, 4-sided, hairy, rough-textured, often reddish in full sun; stipules between leaf bases with 5-8 reddish bristles to 1 cm long.  Leaves opposite, 2-5 cm long, 0.6 cm wide (Yatskievych 2006), narrow, stiff, sessile, bristle-tipped,.  Flowers white-purple, axillary, radially symmetrical, tubular, […]
Diplotaxis muralis sand rocket Brassicaceae DIMU*; Bx, pb (DeCandido 2001); R (DeCandido 2001); -   Diplotaxis muralis is an annual or biennial herb to 50 cm tall, from a taproot, stem branching from base, leafy only near base.  Leaves alternate, narrow, often widest above middle, base narrowing to stalk, margin toothed to lobed.  Flowers yellow, 4-parted, petals to 1 cm long, sepals 0.5 cm, widest near top, narrowed to base, bloomsJune […]
Diplotaxis tenuifolia wall rocket Brassicaceae DITE*; Bx, pb (DeCandido 2001), sw; R (DeCandido 2001); -    Diplotaxis tenuifolia is a perennial herb from a taproot, erect 20-50 cm tall, stems branched from base, leafy up to inflorescence.  Leaves alternate, mostly basal, oblanceolate, toothed to pinnately divided, lobes narrow, toothed, waxy-pale, rather fleshy, unpleasant odor when crushed.  Flowers yellow, 4-parted, petals widest near top, narrowed to base; blooming July-Oct.  Fruit dry, linear capsules 2-parted, […]
Dipsacus sylvestris teasel Dipsacaceae DISY*; Q, cu, l; -     Dipsacus sylvestris is a biennial or short-lived perennial from a taproot to 75 cm long, flowering stem to 2 m tall, prickly especially above, pithy or hollow, branching opposite, producing an overwintering rosette the first year, flowering stalk forms only when rosette becomes about 30 cm in diameter (Werner 1975).  Leaves opposite, prickly on midrib […]
Doellingeria umbellata (Aster umbellatus) flat-topped aster Asteraceae ASUM; Bx, pb (DeCandido 2001); -     Doellingeria umbellata perennial, 1-2 m tall, colonial from creeping rhizome.  Leaves alternate, no basal leaves; stem leaves narrowly elliptic, toothless, 4-16 cm long, 0.7-3.5 cm wide, stalkless (sessile), tapering at both ends.  Flowers: rays white, 7-14, 0.5-0.8 cm long, disk flowers 23-54, yellowish, bracteate base about 0.4 cm long, bracts slender, greenish, overlapping; heads numerous […]
Draba verna Whitlow grass Brassicaceae DRVE*; Bx, pb (DeCandido 2001, Z. Wang 2017); NY (DeCandido 2001); Q, i, j (Z. Wang 2017); K (DeCandido 2001); R (DeCandido 2001); -     Draba verna is an annual or winter annual herb, very small, from a taproot (Yatskievych 2006); flowering stems very slender, 5-20 cm tall. Leaves all in a crowded basal rosette, 1-2 cm long, 0.3-0.4 cm wide, widest above middle, surface hairy, hairs forked and often from a wart-like base.  Flowers white, 0.2-0.3 cm wide, 4 petals […]
Drosera filiformis thread-leaf sundew Droseraceae DRFI; R, cp; -    Drosera filiformis is a carnivorous perennial herb to 25 cm tall.  Leaves all basal, linear thread-like, covered with long, purple, sticky, glandular hairs adapted to attract and trap insects that are digested by enzymes to supply the plant with nitrogen in nutrient-poor, acid bog habitats. Flowers pale purple, radially symmetrical, to 1.5 cm wide, petals 5, […]
Drosera intermedia narrow-leaf sundew Droseraceae DRIN; R, cp (U. Lorimer 2017); -    Drosera intermedia is a  carnivorous, perennial herb to 80 cm tall.  Leaves in a basal rosette and along base of stem, leaf stalks to 5 cm long, blades to 2 cm long, 0.5 cm wide, spatula-shaped, upper side covered with long sticky, glandular hairs, adapted to attract and trap insects that are digested by enzymes […]
Duchesnea indica Indian strawberry Rosaceae DUIN*; Bx, bg, pb, sf, wv (Yost et al. 1991); NY, ct, hb; Q, a, u; R, bd, h, is; -   Duchesnea indica is a perennial herb, trailing, stems several from one root crown (Yatskievych 2006), aggressively colonial from runners, finely hairy, very similar in appearance to native wild strawberry.  Leaves semi-evergreen, alternate, 3-parted, leaflets 2-5 cm long, 1-3 cm wide, margin with rounded teeth.  Flowers yellow, radially symmetrical, ca 1.5 cm wide, petals 5, sepals 5, […]
Echinacea purpurea purple coneflower Asteraceae ECPU*; Bx, pb (DeCandido 2001); -    Echinacea purpurea is a perennial 60-180 cm tall from a root crown, stems with few to no branches.  Leaves alternate, to 15 cm long, 10 cm wide, variable, base abruptly contracted, margin sometimes slightly lobed or toothed.  Flowers in large heads, rays reddish-purple, showy, 3-8 cm long, disk dark, 1.5-3.5 cm wide, raised, becoming conical, covered […]
Echium vulgare viper’s bugloss; blue-weed Boraginaceae ECVU*; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R (DeCandido 2001); -     Echium vulgare is a biennial herb, 30-100 cm tall gray-green, from a taproot, stems bristly-hairy, often with small red dot at base of each bristle; hairs irritating. Leaves initially in a basal rosette, narrow, widest above middle, 6-25 cm long including stalk, 0.5-3 cm wide, stem leaves becoming smaller upward, stalkless.  Flowers bright blue, (occasionally pink […]
Eclipta prostrata  (E. Alba) yerba-de-tajo Asteraceae ECPR*; Bx, sf; -      Eclipta prostrata is an annual, 20-60 cm, often reclining, freely branching, often rooting at nodes, rather fleshy, finely rough-hairy, stems green to reddish, leaf bases often joined across stem as a line or ridge, appearing jointed.  Leaves opposite, stalkless or short-stalked blade lance-shaped to elliptic, 2-10 cm long, 0.4-2.5 cm wide, tip pointed, usually […]
Elodea canadensis common water-weed Hydrocharitaceae ELCA; Bx, br, pb(DeCandido 2001); NY, ct; Q, j (Stalter and Lamont 2002); -   Elodea canadensis is a submerged, rooted or drifting perennial, aquatic, usually in dense beds, dioecious, leafy stems to 1 m long, dichotomously branched, fragile, easily fragmented, roots slender, unbranched, from nodes along stems.  Leaves opposite on lower stem, egg-shaped, small, upper leaves in whorls of 3, 0.6-1.7 cm long, 0.1-0.5 cm wide, linear, margin finely […]
Epifagus virginiana beech drops Orobanchaceae EPVI; Bx, pb, vc; Q, a, cu; R, ar, bd, gb, lp, ml; - Epifagus virginiana is an annual herb, 10-50 cm tall, parasitic on roots of beech trees, plant without chlorophyll, much-branched, slender, stems tan, striped with purplish-brown.  Leaves reduced to scales0.2-0.4 cm long, triangular.  Flowers whitish, about 1 cm long, with 2 purplish stripes, tubular, bilaterally symmetrical, of two kinds, the upper flowers sterile, functionally male, open , lower flowers […]
Epilobium ciliatum American willow-herb Onagraceae EPCI; Q, j (Stalter and Lamont 2002); -     Epilobium ciliatum is a perennial herb from persistent basal rosettes, stems solitary, slender, branched, to 1 m or more (or only to 40 cm, in Fernald), finely hairy above, stems of inflorescence often glandular.  Leaves opposite, sometimes becoming alternate above, lance-shaped, to 12 cm long, 3.5 cm wide, margin sparsely toothed.  Flowers white to pink, radially […]
Epilobium coloratum willow herb Onagraceae EPCO; Bx, pb, sf; Q, j, ri; R, c, cs, gr, h, is, lp, rw, sv, t, w; -     Epilobium coloratum is a perennial herb,to 1 m tall (usually shorter), from overwintering rosettes, stem freely branching, often reddish at nodes (Yatskievych 2006).  Leaves opposite, short-stalked, blade lance-shaped, 4-1.5 cm long, 0.5-2.5 cm wide, often reddish, tip long-pointed (acuminate), base usually rounded, margin closely, veins impressed above, shallowly toothed; winter rosette of small, light […]
Epilobium Genus willow herb Onagraceae -     Epilobium is a genus of perennial (ours) herbs.  Leaves mostly opposite, sometimes alternate in inflorescence.  Flowers radially symmetrical, 4 petals, 4 calyx lobes, stamens 8, style short, ovary inferior, linear.  Fruit dry, a 4-parted capsule splitting open to release numerous plumed seeds.
Epilobium hirsutum hairy willow herb Onagraceae EPHI*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont 2002); R (DeCandido 2001);  -     Epilobium hirsutum is a perennial herb 0.5-2 m tall, colonial from rhizomes, stems erect, densely hairy above, much branched.  Leaves opposite, 5-12 cm long, 1-3 cm wide, lance-shaped to oblong, hairy on both sides, base somewhat clasping, veins nearly parallel to midrib, margin sharply toothed. Leafy bracts of inflorescence alternate, becoming smaller above.  Flowers red-purple, radially […]
Epilobium leptophyllum American marsh willow-herb Onagraceae EPLE; Q, j (Stalter and Lamont 2002); -     Epilobium leptophyllum is a perennial herb, 20-100 cm tall, from slender stolons, stems arising from bulb-like swelling at tip of stolon.  Leaves opposite, the uppermost sometimes alternate, stalkless, often with small leafy clusters in axils; blade 2-7 cm long, 0.1-0.7 cm wide, hairy.  Flowers white to pink, 0.4-0.6 cm long, 4-parted, petal tip notched; flowering stems […]
Epilobium parviflorum small-flowered willow herb Onagraceae EPPA*; Q, j (Stalter and Lamont 2002); R, vi; -     Epilobium parviflorum is a perennial herb to 80 cm, erect, densely hairy, branched.  Leaves opposite, alternate above, 2-8 cm long, hairy on both sides, narrow, sessile but not clasping stem, margin toothed.  Flowers red-purple ca. 1 cm wide, pet 4, deeply notched, 0.4-0.9 cm long.  Fruit dry, a linear capsule 5-8 cm long.  Wetland status: NL  Frequency […]
Epipactis helleborine helleborine Orchidaceae EPHE*; Bx, br, pb, vc; NY, ct, hb, iw; Q, cu, u; K, p; R (DeCandido 2001), ap (E. Danielsen 4/2017); -     Epipactis helleborine is a perennial monocotyledon herb 25-80 cm, from a short rhizome, roots very thick, associated with orchid type endomycorrhizae (Brundrett and Kendrick 1988).  Leaves stalkless, 4-18 cm long, 1.5-8.5 cm wide (Flora of N. America 1993+), smaller upward, base clasping, stem, blade egg-shaped, veins deeply impressed, becoming small, narrow bracts in inflorescence.  Flowers […]
Erechtites hieracifolia pilewort Asteraceae ERHI; Bx, br, pb, sf, vc, wv (Yost et al. 1991); NY (DeCandido 2001); Q, a, cu, j; K, m; R, ah, bk, gr, pr, sv, t; -     Erechtites hieracifolia is an annual, erect, 0.1-3 m tall, stem juicy, often hairy, pale green, roots fibrous.  Leaves alternate, 6–20 cm long, 2–8 cm wide lance-shaped, smaller upwards and clasping stem (Flora of N. America 1993+), margin sharply toothed.  Flowers greenish-white, cylindrical, no rays, tops barely showing above basal bracts; heads cylindrical, 1-1.5 cm long, narrow, […]
Erigeron annuus daisy fleabane Asteraceae ERAN; Bx, br, pb, sf, sn, vc, wv (Yost et al. 1991); NY, hb, iw; Q, a, cu, i, j, rw, tl, wl; K (DeCandido 2001); R, c, cl, cp, cs, d, fk, e, jl, js, mm, pr; -     Erigeron annuus is an annual herb, 30-150 cm tall, from fibrous roots (Yatskievych 2006), stem leafy, usually hairy, often branched above.  Leaves alternate, basal leaves 1.5-8 cm long, 0.3-2 cm wide, long stalked, lance- to egg-shaped stem leaves broadly lance-shaped, narrowed to base, sessile (no stalk) but not clasping stem, surfaces hairy, margins usually toothed, […]
Erigeron philadelphicus Philadelphia fleabane Asteraceae ERPH; Bx, pb, sd, wv (Yost et al. 1991); Q, j, wl; K, fs, p; R, ch; -     Erigeron philadelphicus is a biennial to short-lived perennial herb, 20-80 cm tall, stems hairy, soft, branched only in inflorescence; from fleshy, fibrous roots, appears to sprout from root crown occasionally (Gargiullo personal observation).  Leaves alternate, those of basal rosette and lower stem narrow, 1.5–15 cm long, 1–4 cm wide (Flora of North America 1993+), smaller […]
Erigeron pulchellus robin’s-plantain Asteraceae ERPU; Q, j (Stalter and Lamont 2002); -    Erigeron pulchellus is a perennial, colonial herb from rhizomes, forming leafy rosettes, plant hairy, stems 15-60 cm tall, soft, hollow.  Leaves alternate, often widest above middle, basal leaves narrow to almost round, 2-13 cm long, 0.6-5 cm wide, margins usually toothed, stem leaves few, very reduced upwards, base stalkless, slightly clasping stem.  Flowers in radiate heads, […]
Erigeron strigosus rough fleabane Asteraceae ERST; Bx, br, pb; NY, bl (Stalter and Tang 2002); Q, j (Stalter and Lamont 2002); R (DeCandido 2001); -     Erigeron strigosus is an annual, occasionally biennial herb, 30-70 cm tall, somewhat hairy, roots fibrous, occasionally colonial from rhizomes.  Leaves sparse, basal leaves widest above middle, 3–15 cm long 5–2 cm wide, margin entire or toothed, stem leaves narrower, toothless (otherwise very similar to E. annuus).  Flowers in radiate heads, ray flowers white (sometimes pinkish) 50-100, 0.4-0.6 […]
Erodium cicutarium storksbill; alfilaria Geraniaceae ERCI*; Bx, pb (DeCandido 2001); Q j, wl; R (DeCandido 2001); -      Erodium cicutarium is a winter annual or biennial C3 herb (Ludwig et al. 2010), from a taproot, stems eventually 10-50 cm tall, weak, hairy, very short when first flowering, becoming taller and branched.  Leaves alternate, twice pinnately compound, elongate, widest above middle, leaflets to 2.5 cm, stalkless; overwintering leaves in a rosette.  Flowers pink-purple, petals to […]
Erysimum cheiranthoides (extirpated) wormseed mustard Brassicaceae ERCH*; R recently extirpated (DeCandido 2001); -     Erysimum cheiranthoides is an annual or winter annual, erect 20-100 cm tall, often unbranched, stem leafy.  Leaves alternate, linear, mostly entire, finely hairy.  Flowers bright yellow, ca 0.8 cm wide, 4 petals, in a terminal raceme; blooms June- Aug.; self-fertile (autogamous), but with odor and visited by bees (Mulligan and Kevan 1973).  Fruit dry, a linear pod […]
Erythronium americanum trout lily Liliaceae ERAM; Bx, bg, br, pb, rd, vc; NY, ct; Q, a, cu; R, ah, an, ap (E. Danielsen 4/2017), bd, cr (U. Lorimer 2017), gb, gr, lt, w, wp;  -     Erythronium americanum is a perennial monocotyledon, spring ephemeral herb from deep corms 1.5–2.8 cm wide (bulb-like storage root), floral stem 10-20 cm tall about half underground; extensively colonial from corms produced at the ends of 1-3 short (10 cm) rhizomes from each corm (Flora of North America 1993+); new roots and shoots produced beginning in […]
Eupatorium album var. subvenosum white boneset Asteraceae EUAL2; Bx, pb(DeCandido 2001); R, c, gr; -     Eupatorium album var. subvenosum is a perennial herb, 40-100 cm tall, hairy.  Leaves opposite, almost stalkless, blade 4-13 cm long, 1-4 cm wide, elliptic, hairy, major veins 3, from base of blade, surface sprinkled with tiny translucent dots (use lens), margin coarsely blunt-toothed.  Flowers white, no rays, bracteate base 0.8-1.1 cm long, bracts overlapping, white near […]
Eupatorium altissimum tall boneset Asteraceae EUAL(*); R (DeCandido 2001); -     Eupatorium altissimum is a perennial herb 80 cm to 2 m tall, stems solitary or paired, usually finely whitish hairy above, very leafy. Leaves opposite, stalkless, or almost so, blade 5-12 cm long, 0.8-3 cm wide, narrowly elliptic, pointed at both ends, strongly 3-veined from base, margin toothed above middle.  Flowers white, 5 per head, no […]
Eupatorium Genus boneset; eupatorium Asteraceae -   Eupatorium is a genus of perennial herbs, mostly not branched below inflorescence.  Leaves opposite, sometimes whorled, or upper leaves alternate, blade often with 3 major veins; lower leaves smaller than upper and deciduous as plant flowers.  Flowers white to dull purple, very small, all tubular (discoid), petal lobes 5, pointed, no rays; in dense, mostly 5-flowered […]
Eupatorium hyssopifolium var. laciniatum fringed boneset Asteraceae EULAvL; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont 2002); R (DeCandido 2001); - Eupatorium hyssopifolium var. laciniatum is a perennial herb to 1.5 m tall. Leaves sharply toothed to deeply, pinnately divided, 6-11 cm long, 0.5-1.7 cm wide. Otherwise same as E. hyssopifolium. Flowers dull white, 5 per head, bracteate base about 0.5 cm tall, cylindrical, finely gray-hairy; inflorescence rounded; blooms Aug.-Oct. Fruit A plumed achene. Wetland status: NL. Frequency […]
Eupatorium hyssopifolium hyssop-leaved boneset Asteraceae EUHY; Q, dp, i, j; K, fl, m; R, c, k, ml, sb, ty; - Perennial, 30-140 cm tall, stems solitary, hairy, upper leaves with dense clusters of suppressed axillary branches. Leaves in whorls of 3-4, almost stalkless, blades linear, 5-10 cm long, 0.5-1 cm wide, sprinkled with tiny translucent dots, margin entire. Flowers dull white, 5 per head, bracteate base about 0.5 cm tall, cylindrical, finely gray-hairy; inflorescence rounded; blooms Aug.-Oct. […]
Eupatorium leucolepis white-bracted throughwort Asteraceae EULE; Q (DeCandido 2001); R (DeCandido 2001); -    Eupatorium leucolepis is a perennial herb 40-100 cm tall, stiffly erect, finely gray-hairy.  Leaves opposite, stalkless, blade 3-8 cm long, 0.3-1 cm wide, linear to lance-shaped, thick, finely gray-hairy, sprinkled with tiny translucent dots (use lens), margin sometimes toothed.  Flowers white, 5 per head, bracteate base 0.5-0.7 cm long, bracts hairy, overlapping, tips tapered to a […]
Eupatorium perfoliatum boneset Asteraceae EUPE; Bx, pb (DeCandido 2001); NY, ct; Q, cu, j; R, ar, bd, bk, ca, fk, gr, h, js, lp, pm, sb, ty; -     Eupatorium perfoliatum is a perennial herb, 40-150 cm tall, most parts very hairy, pale, dull green.  Leaves opposite, bases broadly fused across stem, 7-20 cm long, 1.5-4.5 cm wide, tip long-pointed, surface finely puckered, hairy below, widest at base, stem surrounded by leaf, margins toothed.  Flowers dull white, 9-23 per head, bracteate base 0.4-0.6 cm tall, […]
Eupatorium pilosum ragged eupatorium Asteraceae EUPI; Q, j (Stalter and Lamont 2002); R, cl; -    Eupatorium pilosum is a perennial herb, 30-150 cm tall, most parts rough hairy and sprinkled with tiny glandular dots.  Leaves opposite, stalk short to none, blade reduced and sometimes alternate above, lance-shaped, coarsely, unevenly toothed, major veins 3, often lacking teeth near leaf tip.  Flowers white, heads 5-flowered, bracteate base about 0.5 cm tall; inflorescence open, […]
Eupatorium rotundifolium round-leaved boneset Asteraceae EURO; R, gr; -     Eupatorium rotundifolium is a perennial herb, 30-150 cm tall, stems stiff, solitary or in twos, most parts finely hairy.  Leaves opposite, stalkless (sessile), blade rounded to broadly egg-shaped, 2-12 cm long, 1-6 cm wide, usually rough above, tip pointed, base blunt, margin toothed, veins palmate at base.  Flowers white, 5 per head, bracteate base 0.5-0.6 cm […]
Eupatorium serotinum late eupatorium Asteraceae EUSE(*); Bx, pb (DeCandido 2001); NY, ct (planted); Q, j (Stalter and Lamont 2002); K, fl, m; R, c, fk, pr, t; -     Eupatorium serotinum is a perennial herb, (NYS S1, E) 40-200 cm tall, stems densely finely hairy, often grayish-purple; roots fibrous.  Leaves opposite, stalk (petiole) at least 1 cm long hairy; blade 5-20 cm long, 2-10 cm wide, lance-shaped, dull green, sparsely hairy above, paler, hairy below, 3-5 palmate veined, margin toothed, teeth often large, sharp.  […]
Eupatorium sessilifolium upland boneset Asteraceae EUSE2; Bx, pb, vc; R, ar, is, k; -     Eupatorium sessilifolium is a perennial herb, 60-150 cm tall, 1-stemmed from a root crown, stem slender, smooth.  Leaves opposite, stalkless (sessile), blade lance-shaped, very smooth, bright green, 7-18 cm long, 1.5-5 cm wide, thin, base rounded, tip long-tapered, margin toothed, veins pinnate.  Flowers white, in small rayless heads of 5 flowers, bracteate base 0.5-0.6 cm long, […]
Euphorbia cyparissias  (Tithymalus c.) cypress-spurge Euphorbiaceae EUCY*; Bx, vc; NY (DeCandido 2001); Q, i, j; K, m, pl; R (DeCandido 2001); -     Euphorbia cyparissias is a perennial herb, colonial from rhizomes, tap roots may grow to 3 m deep; roots symbiotic with endomycorrhizae Glomus constrictum and G. mosseae (Stahevitch et al. 1988); stems 15-30 cm tall, sap milky.  Leaves alternate linear, to 1-3 long, 0.1-0.3 cm wide, numerous, crowded, in spirals below inflorescence; leaves of infloreacence heart-shaped.  Flowers yellow, very small, above two […]
Euphorbia dentata toothed spurge Euphorbiaceae EUDE*; Q, j Stalter and Lamont 2002); -     Euphorbia dentata is an annual C4 herb (Ludwig et al. 2010), 20-60 cm tall, often branched, sap milky, toxic.  Leaves opposite, linear to egg-shaped, hairy, margin toothed to almost smooth.  Flowers small, inconspicuous, 0.3 cm, lobes of flower cup fringed; inflorescence dense.  Fruit dry, 0.5 cm; blooms July-Sept.  Wetland status: UPL.  Frequency in NYC: Very infrequent.  Origin: Midwestern […]
Euphorbia Genus (including Chamaesyce) spurge Euphorbiaceae -     Euphorbia is a genus of herbs (ours), sap irritating, often milky (Kingsbury 1964).  Leaves diverse.  Flowers mostly yellow to green, no petals or sepals; in tight clusters with male (staminate) flowers, consisting of a single stamen, surrounding a single female (pistillate) flower; the cluster of individual flowers above 4-5 petal-like bracts.  Fruit dry, a 3-parted capsule, usually with […]
Eurybia divaricata (Aster divaricatus) white wood aster Asteraceae ASDI; Bx, bg, br, bz, cf, g, pb, ra, sf, up, vc, wv (Yost et al. 1991); NY, ct, hb, iw, n, rr; Q, a, cu, f, ft, rw; K, p; R, an, ah, ar, c, d, fw, gb, h, is, k, lp, lt, r, sv, w, wp; -   Eurybia divaricata is a perennial herb, 20-100 cm tall, extensively clonal from rhizomes, stems thin, stiff, rather brittle; green to pale tan becoming darker with age, zigzag. Stems with flower bracts persistent through winter (Gargiullo personal observation).  Leaves, alternate, 4-20 cm long, 2-10 cm wide, lower leaves heart shaped, margin sharply toothed, dark green tip long-pointed, […]
Eurybia macrophylla  (Aster macrophyllus) big-leaved aster Asteraceae ASMA; Bx, pb, vc; NY, ct; Q, cu; R, h; -    Eurybia macrophylla is a perennial herb, 20-120 cm, colonial from a rhizome with many tufts of large leaves on short, non-flowering stems, often forming a ground cover in early and mid-summer.  Leaves alternate, mostly basal, stalks elongate, blades 4-30 cm long, 3-20 cm wide, heart-shaped, tip pointed, base lobed, margins with bristle-tipped teeth, upper leaves […]
Eurybia schreberi  (Aster s.) Schreber’s aster Asteraceae ASSC; Bx, pb; Q, cu; -     Eurybia schreberi is a perennial herb 20-120 cm tall, like Aster macrophyllus but inflorescence stems not glandular.  Leaves: sinus at leaf base rather rectangular.  Flowers: ray flowers white, 6-14, bracteate base of flower head 0.5-1 cm long, usually narrower than A. macrophyllus.  Fruit dry, 1-seeded, achene, with tuft of hairs (pappus), wind dispersed  Wetland status: UPL.  Frequency in […]
Eurybia spectabilis  (Aster s.) showy aster Asteraceae - Eurybia spectabilis is  a perennial herb from underground stems, 10-90 cm tall, stems usually glandular-hairy. Leaves mostly basal, blade 2-15 cm long, 0.8-4 cm wide, narrowly elliptic, pointed at both ends, margin shallowly toothed, lower and basal leaves stalked, upper leaves smaller and stalkless. Flowers: rays violet-purple, 15-35, 1-2.5 cm long, bracteate base of flower heads […]
Euthamia graminifolia  (Solidago g.) lance-leaved goldenrod Asteraceae EUGR; Bx, pb (DeCandido 2001); NY, ct; Q, cu, i, j, ri, tl, u; R, ah, c, ca, cs, gr, hs, is, k, lp, js, sv, ty, w; -     Euthamia graminifolia is a perennial herb, 30-150 cm tall, extensively clonal from rhizomes; few or no axillary branches; winter stem brown, flower bases (receptacles) star-shaped, bracts hairy, overlapping (Levine 1995).  Leaves alternate, stalkless, blade 4-13 cm long, 0.3-1.2 cm wide, linear to lance-shaped, 3-veined, sprinkled with minute translucent dots (use lens).  Flowers yellow, rays 15-25, per […]
Euthamia tenuifolia  (E.caroliniana, Solidago t., E. minor) flat-topped goldenrod Asteraceae EUTE; Bx, pb (DeCandido 2001); Q, cu, j, wl; K, m; R, c, cl, cp, gr, gw, k, lp, sv; -   Euthamia tenuifolia is a perennial herb, clonal from rhizomes; stems 30-100 cm tall, often sweet-aromatic.Winter stem brown, slender, receptacles star-shaped, bracts overlapping.  Leaves alternate, stalkless, blade 2.3-7 cm long, 0.1-0.3 cm wide, linear, 1-veined, thin; tufts of small leaves and/or branches in leaf axils.  Flowers yellow, ray flowers 0. 2 cm, heads with 10-21 flowers, bracteate […]
Eutrochium dubium  (Eupatorium d., Eupatoriadelphus dubius) three-nerved joe-pye weed Asteraceae EUDU; Bx, pb(DeCandido 2001); Q f, j; K, p; R (DeCandido 2001); -      Eutrochium dubium is a perennial herb, 40-100 cm tall, stem with purple speckles, sticky-hairy near top.  Leaves in whorls of 3-4, short-stalked, blade 5-12 cm long, 2-7 cm wide, thick, egg-shaped, tip pointed, base abruptly contracted, margin coarsely toothed, strongly 3-veined.  Flowers dull purple 5-8 per head, no rays, basal bracts narrow, in several rows; […]
Eutrochium fistulosum  (Eupatorium f., Eupatoriadelphus fistulosus) hollow-stemmed joe-pye weed Asteraceae EUFI; Bx, pb (DeCandido 2001); NY, iw; Q (DeCandido 2001); K, p; R, c, cs, gb, is, lp, w; -     Eutrochium fistulosum is a perennial herb, much like E. purpureum but larger, to 3 m, stem purple, (usually not spotted), with a conspicuous waxy bloom (strongly glaucous), hollow between nodes.  Leaves in whorls of 4-7, narrowly elliptic to lance-shaped, marginal teeth finer, blunter than those of E. purpureum, pointed at both ends, surface often puckered by impressed veins, […]
Eutrochium maculatum  (Eupatorium m., Eupatoriadelphus maculatus) spotted joe-pye weed Asteraceae EUMA; Bx, vc; NY, iw; Q (DeCandido 2001); R, bm, bg, d, gr, h, lp, pm, sv, w; -    Perennial, 60 cm to 2 m tall, stem speckled or evenly purplish (no waxy bloom), solid in center.  Leaves in whorls of 4-5, stalk short; blade 6-20 cm long, 2-9 cm wide, lance-shaped to narrowly elliptic, pointed at both ends, rough on both sides, veins pinnate, margin sharply toothed.  Flowers dull purple, 9-22 per head, bracteate […]
Eutrochium purpureum  (Eupatorium p.) purple joe-pye weed Asteraceae EUPU; Bx, vc; Q, a, cu; R, ca, cl, gb, wp; -     Eutrochium purpureum is a perennial herb, to 2 m, stem solid (pith intact), slightly waxy (glaucous), purple at nodes internodes green.  Leaves in whorls of 3-4; 8-30 cm long, 2.5-15 cm wide, lance-shaped to egg-shaped, surface sometimes puckered, hairy below with minute yellow speckles (use hand lens) veins pinnate, margin coarsely, tip long-pointed, base pointed, […]
Fagopyrum esculentum buckwheat Polygonaceae FAES*; Q (DeCandido 2001);  -   Fagopyrum esculentum is an annual herb. 20-60 cm tall, stems finely hairy in lines, sheath oblique, truncate; Stipule (ocrea) membranous sleeve-like around stem above leaf stalk (Flora of North America 1993+).  Leaves alternate, broadly triangular-arrow-shaped, lower leaves long-stalked.  Flowers white to pink, 0.2-0.3 cm, 5 petals, 8 stamens, yellow, nectar-bearing glands between stamens, flowers presumably insect […]
Filago germanica  (F. vulgaris) herba impia Asteraceae FIGE*; R (DeCandido 2001); -   Filago germanica is an annual herb, 5-40 cm tall, white-wooly.  Leaves alternate, 1-2 cm long, 0.1-0.3 cm wide, crowded along stem.  Flowers numerous, in whitish wooly heads, 0.4 cm wide, base wooly, bracts papery with dark central part, bristle-tipped, heads in dense, rounded clusters at ends of stems, other flowering stems growing from base of the […]
Fragaria vesca subsp. vesca  (F. americana; F. vesca) woodland strawberry Rosaceae R, h; - Fragaria vesca subsp. vesca is a low, perennial herb,  colonial from runners, most reproduction vegetative; flower stems shorter than leaves, elongating above leaves in fruit. (Bierzychudek 1982). Leaves 3-parted, deeply toothed, hairy below, teeth sharp. Early spring leaves, which replace overwintering leaves, are adapted to high light conditions before canopy closure. Up to 45% of growth […]
Fragaria virginiana wild strawberry Rosaceae FRVI; Bx, pb, wv (Yost et al. 1991); NY, hb; Q, j; R, h; -    Perennial, usually winter-green, low, clonal by runners, stems from a small rhizome.  Leaves alternate, and basal, 3-parted, margins toothed, teeth blunter than above, terminal tooth shorter than lateral ones, early spring leaves adapted to high light conditions, summer leaves of forest plants adapted to shade, late summer overwintering leaves adapted to freezing, shade adapted leaves […]
Froelichia gracilis cottonweed Amaranthaceae FRGR(*); Bx, pb (DeCandido 2001); Q, bp (Zihao Wang 2016); j (Stalter and Lamont 2002); tl (Zihao Wag 2016); K, m (Zihao Wang 2016); R, cp; ml (Zihao Wang 2016); - Froelichia gracilis is an annual C4 herb (Downton 1971), to 70 cm tall, stems slender, to 0.2 cm diameter, appressed white-hairy, usually with divergent basal branches. Leaves opposite mostly on lower part of stem, linear to 8 cm long.1 cm wide, densely silky-hairy on both sides. Flowers very small, in 3 row spirals along whitish wooly spikes 1-3 […]
Gaillardia aristata blanket flower; gaillardia Asteraceae GAAR*; Bx, pb(DeCandido 2001);  -     Gaillardia aristata is a hairy perennial herb, 20-70 cm tall, from a short taproot, colonial from slender roots.  Leaves alternate, narrow, to 15 cm long, 2.5 cm wide, margin entire to pinnately lobed.  Flowers yellow with dark purple base, rays 6-16, 1-3.5 cm long, margins 3-toothed, disk purple,1.5-3 cm wide; blooms and fruits May-Sept.  Fruit dry a […]
Gaillardia pulchella rosering blanket-flower Asteraceae GAPU*; Q, j (Stalter and Lamont 2002); -    Gaillardia pulchella is an annual or short-lived perennial herb, 10-60cm tall, hairy.  Leaves alternate, narrow, to 15 cm long, 2.5 cm wide, margin entire to pinnately lobed.  Flowers purple, tip sometimes yellow, rays 1-2 cm long, disk 1-2.5 cm wide, much like G. aristata.  Wetland status: UPL.  Frequency in NYC: Very infrequent.  Origin:Western US and Mexico.  Habitat: […]
Galanthus nivalis common snowdrop Amaryllidaceae GANI*; Bx, br, pb, rd; R(DeCandido 2001); -     Spring ephemeral, about 15 cm tall, from bulbs, colonial from offsets, sometimes apparently producing viable seed also.  Leaves two, strap-shaped to linear, waxy pale blue-green to 10 cm long, 2.5 cm wide.  Flowers white, solitary, about 2.5 cm wide, dangling, emerging from a short, linear spath, petals, 3, short, inner petals with green markings, notched at […]
Galinsoga parviflora lesser galinsoga Asteraceae GAPA2*; Bx, br, pb, pu; NY (DeCandido 2001); Q (DeCandido 2001); K (DeCandido 2001); R (DeCandido 2001); -      Galinsoga parviflora is an annual C3 herb (Pooter et al. 1990), germinates May-June, 20-60 cm tall, much branched, branches opposite, smooth to sparsely hairy.  Leaves opposite, stalk to 2.5 cm long, blade egg-shaped, to 2-5 cm long, 1-3 cm wide, tip pointed, base blunt, hairy on both sides, margins toothed.  Flowers white to pink, rays 5, […]
Galinsoga quadriradiata  (G. ciliata) galinsoga; quickweed Asteraceae GAQU*; Bx, br, sd, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), hb, rr; Q, cu, i, f; K, ow, p; R, js, l, vi; -     Galinsoga quadriradiata is an annual herb that germinates May-June, 20-70 cm tall, slender, hairy, young stems often reddish-hairy, freely branched; branches opposite.  Leaves opposite, stalk to 6 cm, lower leaves long-stalked, upper leaves almost stalkless, blade egg-shaped, 2.5-7 cm long, 1.5-5 cm wide, hairy on both sides, tip pointed to blunt, base blunt to wedge-shaped, […]
Galium aparine  (including G. spurium) bedstraw; cleavers Rubiaceae GAAP2; Bx, pb, sd, wv (Yost et al. 1991); NY, hb, iw; Q, c, cu, f, ft, j, wl; K, m; R, bd, c, gb, h, lp, ok, r; -     Galium aparine is an annual herb, from a small taproot, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); prostate, or climbing over low vegetation, somewhat translucent-succulent, bright green, stems to 1 m long, branched from base, not branched much above, stem rough, clinging-scratchy, sharply 4-angled.  Leaves stalkless (sessile), in whorls of 4-8, rough, narrow, […]
Galium asprellum rough bedstraw Rubiaceae GAAS; Bx, pb (DeCandido 2001); -    Galium asprellum is a perennial, spreading, clambering, stems 0.5-1.8 m long, weak, much branched, often matted, 4-angeled with tiny hooks lining angles.  Leaves in whorls of 4-6, narrowly elliptic, widest above middle, to 2 cm long, 0.6 cm wide, tip pointed, margins rough.  Flowers white, radially symmetrical, petal lobes 4; inflorescences of small branched clusters near […]
Galium circaezans wild licorice Rubiaceae GACI; Bx, pb (DeCandido 2001); -    Galium circaezans is a perennial herb 20-60 cm tall, erect or ascending, stem 4-angled, wiry, smooth to finely hairy, simple to stiffly branched from base.  Leaves in whorls of 4, 2-5 cm long, 1-2.5 cm wide, elliptic, often densely hairy, tip blunt, 3-5 major veins.  Flowers greenish-purple, minutely hairy, radially symmetrical, petal lobes 4, pointed at […]
Galium Genus bedstraw; cleavers Rubiaceae -    Galium is a genus of annual or perennial herbs, stems slender, 4-angled.  Leaves whorled.  Flowers 4-parted, radially symmetrical, tubular, petal lobes about as long as tube, small, stamens 4, ovary inferior, 2-parted, styles 2 (use lens).  Fruit dry (ours), 2-parted, each part rounded, 1-seeded.  
Galium mollugo bedstraw Rubiaceae GAMO*; Bx, pb, vc; Q, u, wl; K, m; R, ar, lp, sm; - Galium mollugo is a perennial herb 0.25-1.2 m long, from a branched tap root; spreading by rhizomes (Mersereau and DiTommaso 2003); stems numerous, top more-or-less upright, weak-stemmed from a reclining base, stems smooth to short hairy below, 4-angled.  Leaves in whorls of 6-8 on main stem, 6 on branches, 1-2.5 cm long, about 0.3 cm wide, […]
Galium obtusum blunt-leaf bedstraw Rubiaceae GAOB; R (DeCandido 2001); -     Galium obtusum is a perennial herb, stems matted, branched, 20-80 cm long, 4-sided, angles smooth, nodes densely bearded.  Leaves in whorls of 4, 1-3 cm long, 0.1-0.6 cm wide, linear to lance-shaped, tips blunt, margins rough.  Flowers white, 4-parted, 0.2-0.3 cm wide, in clusters of 3-5 at ends of stems; blooms May-July.  Fruit dry, 2-parted capsule, 0.4-0.5 […]
Galium palustre marsh-bedstraw Rubiaceae GAPA; Bx, pb (DeCandido 2001); R, gr; -     Galium palustre is a perennial herb, stems slender 20-60 cm long, 4-sided, minutely barbed on angles, sparsely branched.  Leaves in whorls of 2-6, about 0.5-1.5 cm long, linear, blunt-tipped, margin rough.  Flowers white, 4 parted, 0.4 cm wide; numerous, in many-branched clusters; blooms July- Aug.  Fruit dry, 2-parted capsule, 0.2 cm wide.  Wetland status: OBL.  Frequency in […]
Galium tinctorium  (G. brevipes) stiff marsh-bedstraw Rubiaceae GATI; Q (DeCandido 2001); R (DeCandido 2001); -     Galium tinctorium is a perennial herb, stems slender, to 40 cm long, much branched, matted, roughened by minute back-pointing hooks.  Leaves in whorls of 4-6, 1-2 cm long, narrow, tips blunt.  Flowers whitish, minute, four-parted, 0.1 cm, in clusters of 2-3 on stalks less than 1 cm long, at ends of stems; blooms June-Sept.  Fruit dry 2-parted […]
Galium trifidum  three-lobed bedstraw Rubiaceae GATR; Bx, pb (DeCandido 2001); R, t; -   Galium trifidum is a perennial herb, slender, to 40 cm, much branched, matted, roughened by minute back-pointing hooks.  Leaves mostly in whorls of 4, linear, 1-2 cm long, tips blunt.  Flowers whitish, minute 3-parted, 0.1 cm wide, mostly solitary on stalks longer than 1 cm, from nodes; blooms and fruits July-Sept.  Fruit dry, round, 2-parted capsule, about […]
Galium triflorum sweet-scented bedstraw Rubiaceae GATR; Bx, pb (DeCandido 2001); Q, cu (Greller 1977); R; -     Galium triflorum is a perennial herb, stems 20-80 cm long, 4-sided, angles usually minutely barbed, prostrate or sprawling on other vegetation.  Leaves mostly in whorls of 6 on main branches, 1.5-5 cm long, vanilla-scented, narrowly elliptical, abruptly sharp-tipped, margin rough.  Flowers greenish-white, 0.2-0.3 cm wide, in loose clusters; blooms June-Aug.  Fruit dry, about 0.2 cm wide, bristly. […]
Gamochaeta purpurea (Gnaphalium purpureum) spoonleaf purple everlasting Asteraceae GNPU; Q, fh (M. Feder p.c.); R (DeCandido 2001); - Gamochaeta purpurea is an annual to biennial herb, thinly wooly, 10-40 cm tall.  Leaves alternate, the lowest spatula-shaped to 10 cm long, 2 cm wide, tip rounded, often forming basal rosette.  Flowers purplish, no rays, only tips showing at top of head, bracteate base 0.3-0.5 cm long, wooly, bracts pale brown, purplish or green with white-web-like hairs, […]
Genista tinctoria dyer’s greenweed Fabaceae GETI*; Bx, pb (DeCandido 2001); -     Genista tinctoria is an herb to 1 m tall, slender, striped.  Leaves alternate, simple, to 1 cm long, 0.3 cm wide, elliptic to lance-shaped, bright green.  Flowers yellow, to 1.5 cm wide, bilaterally symmetrical, pea-flower-shaped, in unbranched clusters among leafy bracts; blooms June-July.  Fruit dry pods flattened, to 3 cm long, 0.5 cm wide.  Wetland status: UPL.  […]
Gentiana andrewsii  closed gentian; bottle gentian Gentianaceae GEAN; R (DeCandido 2001); -    Gentiana andrewsii is a perennial herb, to 1 m tall from a stout root crown with long, coarse roots, stems clustered, hairless, usually unbranched.  Leaves opposite, stalkless, blade to 15 cm long, 4 cm wide, lance-shaped, pointed at both ends, margin hairy.  Flowers blue above, base whitish, radially symmetrical, to 4 cm long, tubular, somewhat swollen, […]
Gentiana saponaria soapwort gentian Gentianaceae GESA; R, gb (possibly extirpated); -     Gentiana saponaria is a perennial herb to 70 cm tall.  Leaves opposite, to 10 cm long, elliptic or widest above middle, margin hairy.  Flowers blue, to 5 cm long, 1.5 cm wide, tubular, inflated on one side, lobes narrowly opening, erect or curved inward, blooms Sept.-Oct.  Fruit dry, 2-parted capsule with numerous seeds.  Wetland status: FACW.  Frequency […]
Geranium carolinianum Carolina crane’s-bill Geraniaceae GECA; Bx, pb, vc, wv (Yost et al. 1991); Q, j (Stalter and Lamont 2002); K, fl (Z. Wang 2016); R (DeCandido 2001); -     Geranium carolinianum is an annual herb, with several stems, freely branched, to 60 cm long, often reddish, densely hairy; from a taproot, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); stipules to 1 cm long, pointed (Yatskievych 2006).  Leaves alternate, stalk to 15 cm long, blade, round to kidney-shaped, to 7 cm long and […]
Geranium Genus wild geranium Geraniaceae -    Geranium is a genus of annual or perennial herbs, often hairy (ours).  Leaves alternate or sometimes opposite, palmately divided or lobed, lobes usually toothed or lobed again, veins usually impressed.  Flowers radially symmetrical, petals 5, free, inversely egg-to heart-shaped, (obovate to obcordate); sepals alternating with petals, persistent in fruit; stamens 10; ovary superior, a deeply 5-lobed […]
Geranium maculatum wild geranium Geraniaceae GEMA; Bx, pb, vc, wv (Yost et al. 1991); NY, iw; Q, a, cu, f; K (DeCandido 2001); R, c, gb, w; -     Geranium maculatum is a perennial herb, to 60 cm tall, stems clustered, hairy (Yatskievych 2006), from a short, stout rhizome; rhizome dormancy broken by cold; leaf and flower buds form late in season following seed dispersal (Martin 1965).  Leaves opposite, few, mostly basal, stalk to 30 cm long on basal leaves, blade round in outline, […]
Geranium molle dove-foot crane’s-bill Geraniaceae GEMO*; R (DeCandido 2001);  -     Geranium molle is an annual herb to 50 cm tall from a taproot, stems branched from base, spreading, softly hairy.  Leaves alternate, mostly basal, kidney-shaped, to 5 cm wide, divided to middle of blade into 5-9, 3-lobed segments, lobes shallow, upper leaves progressively reduced upwards.  Flowers pale purple, numerous, petals to 0.7 cm long, deeply notched […]
Geranium robertianum herb-robert Geraniaceae GERO*; NY, iw; Q, j (Stalter and Lamont 2002); -     Geranium robertianum is an annual or biennial herb, to 60 cm tall from a taproot, stems weak, branched, spreading, hairy, often red, strongly scented; roots sparsely or facultatively associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves alternate, palmately divided to base into 3-5 segments, the center segment stalked, all segments lobed or divided, tips […]
Geranium sibiricum Siberian crane’s-bill Geraniaceae GESI*; Bx, pb, rd, wv (Yost et al. 1991); -     Geranium sibiricum is an annual or short-lived perennial herb, stems 0.3-1 m long, weak, thin, hairy, often reddish.  Leaves alternate, palmately divided, 4-7 cm wide, kidney-shaped, 3-5 coarsely toothed divisions.  Flowers pale pink, small, ca 1 cm wide, petals hardly longer than sepals, sepals 0.5-0.7 cm long, tipped by a short awn, style column 1-1.5 cm […]
Geum canadense white avens Rosaceae GECA; Bx, br, sf, vc; NY, hb; Q, a, cu, f, ft, j; K, p; R, c, bm, fw, gb, sb, t, wt; -     Geum canadense is a perennial herb from a short rhizome and root crown, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); stem 0.4-1 m tall, clustered from root crown, upper stem velvety-hairy; stipules leaf-like, 2 cm long, 1 cm wide, margin toothed (Yatskievych 2006).  Leaves alternate, stalks long on basal leaves, reduced on […]
Geum laciniatum rough avens Rosaceae GELA; Bx, vc; -     Geum laciniatum is a perennial herb 0.4-1 m tall, usually with several branched stems; hairy, stipules present.  Leaves alternate, lower leaves long-stalked, blade usually pinnately compound, leaflets coarsely toothed to irregularly lobed, winter rosette leaves often dark blue green, mottled with pale areas, stem leaves 3-parted, irregularly toothed and lobed, upper leaf segments widest above […]
Geum vernum spring avens Rosaceae GEVE; Bx, vc (Greller et al. 2006); - Geum vernum is a spring annual herb, 30-60 cm tall. Similar to above spp. Leaves alternate. Pinnate. leaflet margins toothed, hairy. Flowers yellow to white, petals 0.1-0.2 cm long, shorter than styles. Fruit dry, in rounded heads. Achenes 0.2-0.3 cm long.Styles persistent as hooks. Wetland status: FAC+.  Frequency in NYC: Very infrequent. Origin: Native. Habitat: Dry woods.
Glechoma hederacea gill-over-the-ground Lamiaceae GLHE*; Bx, br, pb, sl, wv (Yost et al. 1991); NY, ct; Q, j (Stalter and Lamont 2002); K, p; R, bd, d, is, jw, rp; -    Glechoma hederacea is a perennial, creeping, colonial herb from slender stolons or shallow rhizomes, rooting at nodes, mat-forming, often semi-evergreen, stem square, 10- 40 cm long, nodes hairy, bases of leaf stalks joined across stem, bruised or cut leaves strongly minty-fragrant.  Leaves opposite, stalk slender, 3-5 cm long, blade rounded, heart to kidney-shaped, 1-4 cm […]
Gnaphalium uliginosum marsh cudweed Asteraceae GNUL*; Bx, pb (DeCandido 2001); Q, a; -    Gnaphalium uliginosum is an annual herb, 5-25 cm tall, densely white wooly, diffusely branching.  Leaves alternate, narrow, to 4 cm long, 0.5 cm wide, slightly wooly.  Flowers whitish, no rays only tips showing at top of head amid papery bracts, heads brown, rounded, bud-like, bracteate base 0.2-0.3 cm long, in terminal and axillary clusters, shorter than […]
Hackelia virginiana stickseed Boraginaceae HAVI; Bx, pb (DeCandido 2001); NY, iw; R (DeCandido 2001); -      Hackelia virginiana is a biennial herb, stout, to 1 m tall, finely hairy, branches numerous, perpendicular to stem axis.  Leaves alternate, stalked, blade elliptic, basal leaves rounded, to 30 cm long, 7 cm wide, usually withering before plant flowers, stem leaves pointed at both ends, stalkless (sessile), becoming small bracts on flowering stems.  Flowers white, […]
Hedeoma pulegioides American pennyroyal Lamiaceae HEPU; Bx, pb (DeCandido 2001); -    Hedeoma pulegioides is an annual herb to 40 cm tall, stem branched, curly-hairy, especially above.  Leaves opposite, elliptic to egg-shaped, 1-3 cm long, margin sometimes toothed, main leaves stalked.  Flowers blue, tubular, bilaterally symmetrical, to 0.5 cm long, weakly 2-lipped, upper lip erect, notched, scarcely longer than calyx, calyx tubular, ribbed, 2-lipped, lips 0.2 cm, ovary […]
Helenium autumnale common sneezeweed Asteraceae HEAU; R (DeCandido 2001); -    Helenium autumnale is a perennial herb, 50-150 cm tall, roots fibrous.  Leaves alternate, almost stalkless, blade 4-15 cm long, 0.5-4 cm wide, narrowly elliptic, pointed at both ends, base extending along stem as wings, lower leaves deciduous  Flowers yellow, rays 13-21, 1.5-2.5 cm long, wedge-shaped, tips 3-lobed, disk yellow, 0.8-2 cm wide, domed, heads mostly solitary […]
Helenium flexuosum  (H. nudiflorum) southern sneezeweed Asteraceae HEFL(*); R, sb; -     Helenium flexuosum is a perennial herb, fibrous rooted, 20-120 cm tall, stems hairy, winged by extended leaf bases, branches stiffly ascending.  Leaves alternate, stalkless, base extending down stem, blade narrow, 3-12 cm long, 1-2 cm wide, the lower soon deciduous, densely sprinkled with tiny, translucent dots (use lens).  Flowers yellow, rays about 8-13, wedge-shaped, 1-2 cm […]
Helianthus angustifolius swamp sunflower Asteraceae HEAN; R (DeCandido 2001); -   Perennial herb, 0.5-1.5 m tall (NYS S2, T), stems solitary, hairy.  Leaves alternate except near base, 5-15 cm long, 0.2-1 cm wide, linear, stalkless, margin rolled under, dark green, rough above, pale, hairy below, basal leaves, when present, stalked and blade wider.  Flowers yellow, rays 10-15, 1.5-3 cm long, disk red-purple 1.5-2 cm wide, basal bracts […]
Helianthus annuus common sunflower Asteraceae HEAN2(*); Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, j (Stalter and Lamont 2002); K, fs; R (DeCandido 2001); -     Helianthus annuus is a coarse annual herb, to 3 m, from fibrous roots, stems very rough-hairy, branched. Leaves mostly alternate, but upper or lower leaves sometimes opposite, blade 2-30 cm long very rough both sides, broadly egg to heart-shaped, tip pointed, base rounded to lobed, veins palmate at base, margin coarsely, irregularly toothed, stalk long.  […]
Helianthus decapetalus thin-leaved sunflower Asteraceae HEDE; Bx, br, pb, vc; NY, hb, iw; R (DeCandido 2001); -     Helianthus decapetalus is a perennial herb, colonial from rhizomes, stem 0.5-1.5 m tall, smooth below hairy inflorescence.  Leaves opposite below, usually alternate above (in inflorescence), stalk 2-6 cm long, blade 8-20 cm long, 3-8 cm wide, tip long-pointed, base abruptly narrowed, extending down stalk, thin, pale below, somewhat rough textured, margin sharply toothed, 3-veined at […]
Helianthus divaricatus woodland sunflower Asteraceae HEDI; Bx pb, vc; R, sc; -     Helianthus divaricatus is a perennial herb, colonial from long rhizomes, 0.5-1.5 m tall, stem smooth below inflorescence, often waxy-pale.  Leaves subentire, all opposite, nearly stalkless, blade 5-18 cm long, 1-5 cm wide, lance-shaped, widest near base, tapering to tip, 3-veined at rounded base, rough textured above, hairy below.  Flowers yellow, rays 8-15, 1.5-3 cm long, not […]
Helianthus Genus sunflower Asteraceae -    Helianthus is a genus of herbs, coarse annuals or perennials, stems erect, branching mostly opposite, becoming somewhat woody in age.  Leaves opposite or upper ones alternate, blade simple.  Flowers mostly yellow, rays without male or female parts (neutral), large, disk fflowers fertile, perfect (both male and female), basal bracts usually green, ffloral base (receptacle ) covered with […]
Helianthus giganteus tall sunflower  Asteraceae HEGI; Bx, pb (DeCandido 2001); R (DeCandido 2001); -   Helianthus giganteus is a perennial herb, roots fleshy, thickened, stems 1-3 m tall, usually hairy.  Leaves opposite near base, alternate above, stalk short, blade 8-20 cm long, 1-3.5 cm wide, lance-shaped, rough above, usually hairy below, tip long-pointed, 3-veined at base, margin toothed to almost smooth.  Flowers yellow, rays 10-20, 1.5-3 cm long, disk yellow, 1.5-2.5 […]
Helianthus mollis  ashy sunflower  Asteraceae HEMO*; R (DeCandido 2001); -   Helianthus mollis is a perennial herb, stems 0.5-1 m tall, densely gray-hairy, usually colonial from thick rhizomes.  Leaves opposite, the upper sometimes alternate, stalkless, blade 6-15 cm long, 2-6 cm wide, broadly lance- to nearly heart-shaped, base slightly lobed, gray- rough above, gray-hairy below, base 3-veined, margin finely toothed to smooth.  Flowers yellow, rays 16-35, 1.5-3.5 cm […]
Helianthus petiolaris plains sunflower Asteraceae  HEPR*; Q, j (Stalter and Lamont 2002); -    Helianthus petiolaris is an annual herb, similar to H. annuus but smaller, less than 1 m tall.  Leaves stiffly hairy, pale.  Flowers yellow, disk dark, 1-2.5 cm wide, scales between disk fflowers white-bearded at tips, basal bracts narrow, tapering to tip; blooming and fruiting June-Sept.  Fruit 1-seeded achene.  Wetland status: UPL.  Frequency in NYC: Very infrequent.  Origin: Midwestern US.  […]
Helianthus tuberosus Jerusalem artichoke Asteraceae HETU*; Bx, pb (DeCandido 2001), wv (Yost et al. 1991); NY (DeCandido 2001); Q, j (Stalter and Lamont 2002; K (DeCandido 2001); R (DeCandido 2001); -     Helianthus tuberosus is a perennial herb, colonial from rhizomes bearing ffleshy, irregular, white to reddish, edible tubers at their ends. New stems arise from tubers beginning in April or May; Stems hairy, stout, to 3 m tall, to 3 cm diameter, becoming woody, erect, often branching.  Leaves alternate above, opposite on lower third of stem, […]
Heliopsis helianthoides oxeye; false sunflower Asteraceae HEHE2; Bx, pb (DeCandido 2001), wv (Yost et al. 1991); Q (DeCandido 2001);  -     Heliopsis helianthoides is a perennial herb, 50-150 cm tall.  Leaves opposite, stalks 0.5-3.5 cm long, blade 5-15 cm long, 2.5-8 cm wide, egg-shaped, tip long-pointed, base blunt, 3-veined, margin toothed, rather smooth above.  Flowers pale yellow, rays 8-16, 1.5-4 cm long, fertile (i.e. with stigma and ovary) disk 1-1.5 cm high, 1-2.5 cm wide, basal bracts […]
Helonias bullata swamp pink Liliaceae HEBU; R, cp (Lamont and Young 2002; planted but spreading); -    Helonias bullata is a perennial monocotyledon herb, flowering stem to 1 m tall, unbranched, hollow.  Leaves basal, to 30 cm long, semi-evergreen, lance-shaped, stem leaves bract-like.  Flowers pink, to 1 cm wide, 6-parted, fragrant, anthers blue; ffinflorescence a crowded, thick, oval spike 3-10 cm long, to 3 cm wide, at top of stem.  Fruit dry, 3-lobed, capsule, […]
Hemerocallis fulva day lily Liliaceae HEFU*p; Bx, br, pb, rd, sf, vc; NY, hb, iw; Q, a, cu, j, u; K, p; R, bm, c, ca, cg, gb, h, ok, ro;  -     Hemerocallis fulva is a perennial monocotyledon herb, colonial from tubers along dark orange-brown, fleshy roots.  Leaves alternate, basal, strap-like with prominent midrib, margin entire; inflorescence leaves reduced to bracts.  Flowers orange, base yellow, petals 3, sepals 3, very similar, about 12 cm wide across top, , funnel-shaped, showy; inflorescence branched, stem to 1 m; blooms June-July.  […]
Hemerocallis lilioasphodelus  (H. flava) yellow day lily Liliaceae HELI*; Q, j (Stalter and Lamont 2002); -     Hemerocallis lilioasphodelus is a perennial monocotyledon herb, colonial from tubers, ffleshy roots.  Leaves alternate, basal, strap-like with prominent midrib.  Flowers lemon yellow, fragrant, otherwise same as H. hemerocallis.  Origin: Europe.  Wetland status: UPL.  Frequency in NYC: Very infrequent.  Habitat: Rarely escapes from cultivation but occasionally found in overgrown horticultural sites. Many hybrids and cultivars. Hybrids of Hemerocallis not […]
Heracleum mantegazzianum giant hogweed Apiaceae HEMA*; Bx, pb (DeCandido 2001), rd, wv (Yost et al. 1991); -     Heracleum mantegazzianum is a biennial to short-lived perennial herb, fflowering only once (monocarpic), to 5 m tall, sap sensitizes skin to UV radiation, can cause severe dermatitis; stems to 10 cm thick, with purplish spots.  Leaves alternate, leaf stalk inflated, blade to 3 m long, 80 cm or more wide, triangular in outline, deeply pinnately […]
Heracleum maximum  (H. lanatum) cow parsnip Apiaceae HELA; Bx, br, pb (DeCandido 2001); R (DeCandido 2001); -     Heracleum maximum is a stout perennial herb to 3 m tall, stems single below inflorescence, ribbed, sometimes hairy.  Leaves alternate, leaf stalks broadly sheathing stem, almost pouch-like, pinched in and lobed at top, blade 3-parted, to 30 cm long and wide, leaflets lobed and toothed, sparsely hairy above, densely ffine-hairy below lateral leaflets asymmetrical.  Flowers white […]
Hesperis matronalis dame’s rocket Brassicaceae HEMA*; Bx, br, pb, wv (Yost et al. 1991); NY (DeCandido 2001); R, bm; -    Hesperis matronalis is a biennial to Perennial herb, 0.5-1 m tall, often branched above.  Leaves alternate, stalk short or none, blade to 12 cm long, 4 cm wide (Yatskievych 2006), lance-shaped, hairy on both sides, margin sparsely toothed.  Flowers purple to white, fragrant, 2-2.5 cm wide, showy, petals 4, narrowed at base (clawed), sepals 4, purple-green, […]
Heterotheca subaxillaris camphorweed  Asteraceae HESU(*); Bx, pb (DeCandido 2001); Q, fr, i, j, tl; K, fl, m, pl; R (DeCandido 2001); -    Heterotheca subaxillaris is an annual or biennial herb, taprooted, stem 0.2-1.5 cm tall (usually less than 50 cm); hairy, aromatic, sticky.  Leaves alternate, both basal and stem, stalk winged, upper leaves sessile, blade 2-9 cm long, 1-3 cm wide, reduced upwards, upper leaves broad, egg-shaped to oblong, base clasping stem, surface hairy-sticky on both sides, […]
Heuchera americana alum root Saxifragaceae HEAM; Bx, pb, vc; NY, ct; R (DeCandido 2001); -     Heuchera americana is a perennial herb, 30-80 cm tall, from rhizomes, flowering stem leafless except for few small bracts.  Leaves basal, 4-15 cm long and wide, nearly round, often mottled with white, 5-9 lobed, finely hairy on both sides, margin toothed, base deeply lobed.  Flowers greenish to purplish, radially symmetrical, 5-parted, 0.3-0.5 cm, wide, stamens longer […]
Hibiscus moscheutos  (H. palustris) rose-mallow Malvaceae HIMO; Bx, cm (planted), pb; Q, j, u; K, fs; R, c, gb, go, gr, h, is, lp, mls, pr, ro, sb, t, wp;  -    Hibiscus moscheutos is a perennial herb, 1-2 m tall, stems usually in clumps, thick, finely gray-hairy, usually unbranched below inflorescence, often in small colonies from deep, ffibrous roots.  Leaves alternate, broadly ovate, toothed, sometimes lobed near tip, hairy below, rather dull green.  Flowers pink to white with red eye,10-20 cm wide, very showy, solitary, open for […]
Hibiscus trionum flower of an hour Malvaceae HITR*; NY, bl (Stalter and Tang 2002); R (DeCandido 2001); -     Hibiscus trionum is an annual herb to 50 cm tall, very hairy, branching.  Leaves alternate, deeply 3-parted, middle lobe longest, segments oblong, coarsely toothed or lobed.  Flowers pale yellow with purple center, broad, lasting only a few hours, petals 5, to 4 cm long, widest at top, calyx becoming infflated, 5-angled or winged, coarsely hairy.  Fruit enclosed […]
Hieracium aurantiacum orange hawkweed Asteraceae HIAU*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont 2002); R (DeCandido 2001); -     Hieracium aurantiacum is a perennial herb, 10-60 cm tall, sap milky, stems from rhizomes, aggressively colonial from spreading basal stems (stolons), most parts long-hairy, hairs gland-tipped on upper stem.  Leaves mostly in a basal rosette, 5-25 cm long, including stalk, 1-3.5 cm wide, narrow, widest above middle, tip blunt, base narrowing gradually to winged stalk, […]
Hieracium caespitosum  (H. pratense) field hawkweed Asteraceae HICA*; Bx, pb (DeCandido 2001); NY, bl (Stalter and Tang 2002); Q, j, ri; K (DeCandido 2001); R, lp; -     Hieracium caespitosum is a perennial herb, colonial from rhizomes and short, thick stolons, sap milky, stems 25-90 cm tall, long-hairy, wooly and blackish-glandular hairy above.  Leaves mostly in a basal rosette, 5-25 cm long, including stalk, 1-3.5 cm wide, long-hairy both sides, flowering stem with 0-2 small leaves.  Flowers bright yellow, all rays, bracteate base 0.6-0.8 […]
Hieracium canadense  (H. kalmii var. kalmii) Canada hawkweed Asteraceae HIKA; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, a; K, p; R (DeCandido 2001); -     Hieracium canadense is a perennial herb 15-100 cm tall, stem solitary, usually hairy, sap milky.  Leaves alternate, 3-12 cm long, 0.7-4 cm wide, elliptic to widest above middle (oblanceolate), usually with cushions of star-shaped hairs above, long-hairy below (use lens), basal rosette deciduous before flowering, stem leaves 8-20, stalkess (sessile), somewhat clasping, elliptic to egg-shaped, […]
Hieracium Genus hawkweed Asteraceae -    Hieracium is a genus of perennial herbs with milky sap (latex), usually hairy to some extent, roots fibrous, from a rhizome or crown.  Leaves mostly in a basal rosette, sometimes a few alternate leaves on flowering stem.  Flowers mostly yellow, all rays (like dandelions), heads with basal bracts overlapping.  Fruit dry, 1-seeded achene, deeply ribbed, with a […]
Hieracium lachenalii  (H. vulgatum) European hawkweed Asteraceae HILA*; R (DeCandido 2001); -    Hieracium lachenalii is a perennial herb 15-100 cm tall, sap milky, plant sparsely long-hairy, from a root crown or short rhizome.  Leaves mostly basal, blade 2-13 cm long, 1.5-5.5 cm wide, elliptic, pointed at both ends, long-hairy, margin coarsely, sparsely, toothed towards base, stem leaves at least 2, small.  Flowers yellow, all rays, dandelion-like, 40-80 per […]
Hieracium paniculatum panicled hawkweed Asteraceae HIPA; Bx, pb (DeCandido 2001);  -     Hieracium paniculatum is a perennial herb, 0.3-1.5 m tall, sap milky, stems usually solitary, , from a short root crown, 30-150 cm tall, lower stem long-hairy, upper smooth, leafy to inflorescence.  Leaves alternate, no rosette, lower leaves stalked, blade 4-12 cm long, 1-2 cm wide, thin, usually hairless, white-waxy below, margin few-toothed, soon deciduous, upper […]
Hieracium pilosella mouse-ear hawkweed Asteraceae HIPI*; Q, cu (Greller 1985); R (DeCandido 2001); - Hieracium pilosella is a perennial herb, sap milky, rhizomatous, mat-forming colonial from thread-like, leafy stolons, stem 3-25 cm tall, sticky, blackish-hairy, also with long hairs.  Leaves of basal rosette 2-13 cm long, 0.6-2 cm wide, widest above middle (oblanceolate), green, with long hairs above, tan or white wooly below, especially when young, flowering stem leafless or […]
Hieracium piloselloides  (H. florentinum) king-devil Asteraceae HIPI2*; Bx, pb (DeCandido 2001); Q, a, tl; R, al, d, mm, sv; -      Hieracium piloselloides is a perennial herb, 20-100 cm tall, from a short rhizome, roots with short or no rhizomes, sap milky; stem naked with 1-2 small leaves.  Leaves of basal rosette 3-18 cm long, including stalk, 0.5-2 cm wide, widest above middle, pale waxy blue-green, sparsely long-hairy on both sides, flowering stem with 1-2 […]
Hieracium sabaudum Savoy hawkweed Asteraceae HISA*; R (DeCandido 2001); -    Hieracium sabaudum is a perennial herb 15-100 cm tall, stem solitary, usually hairy, sap milky (similar to H. canadense) but lower stem and lower leaf surface with bulbous-based hairs (use lens) that are not star-shaped in cushions.  Flowers yellow, all rays; bracteate base of flower head dark; inflorescence terminal, branching; blooms and fruits Aug.-Oct.  Fruit dry, 1-seeded achenes.  […]
Hieracium venosum rattlesnake weed Asteraceae HIVE; Bx, pb (DeCandido 2001); R (DeCandido 2001); -    Hieracium venosum is a perennial herb, sap milky, stems 20-80 cm tall, usually hairless.  Leaves mostly basal, 3-16 cm long, including stalk, 0.8-5 cm wide, elliptic to widest above middle, midrib and veins reddish-purple, very conspicuous, blade often purplish on underside, long-hairy along margin and near base; stem leaves 0-3, small.  Flowers yellow, all rays, 15-40 […]
Hieracium x floribundum [caespitosum × lactucella] pale hawkweed  Asteraceae HIFL*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, j (Stalter and Lamont 2002); K (DeCandido 2001); R, cl, e;  -    Hieracium x floribundum is a perennial herb, sap milky, colonial from rhizomes and leafy stolons, stem 20-80 cm tall, sparsely long-hairy.  Leaves mostly in a basal rosette, 3-14 cm long, including stalk, 0.6-2 cm wide, surface waxy-pale, mostly hairless above, usually long-hairy below; flowering stem with 0-2 small leaves.  Flowers yellow, all rays, bracteate base (involucre) […]
Honckenya peploides subsp. robusta  (Arenaria p.) sea-beach sandwort Caryophyllaceae  HOPE; Q, rb; -    Honckenya peploides subsp. robusta is a perennial, reclining, mat forming herb from rhizomes and runners rooted deeply in sand, stems 10-50 cm long, pale, succulent.  Leaves opposite, each pair at right angles to next, blades yellow-green, 1-2 cm long, thick, stalkless, (sessile), tip pointed, bases broad almost meeting across stem, making ends of non-flowering stems […]
Hosta ventricosa plantain lily; funkia Liliaceae HOVE*; Bx, pb (DeCandido 2001); R (DeCandido 2001); -     Hosta ventricosa is a perennial monocotyledon herb  from a dense mat of thick roots; flowering stem to 1 m, leafless.  Leaves all basal, egg to heart-shaped, about 10 cm wide, most often solid green or white-striped, veins impressed, parallel to midrib.  Flowers pale blue, 5 cm long, radially symmetrical, tubular, funnel-shaped, petal lobes flaring, tips pointed, […]
Hottonia inflata featherfoil Primulaceae HOIN; R, t; -    Hottonia inflata is a winter annual aquatic herb to 50 cm long, usually submersed, growing in Autumn and winter, blooming in spring, stems hollow, swollen.  Leaves to 6 cm long, deeply pinnately divided, segments linear, all densely clustered at top of stem.  Flowers white, tubular, sepals 5, to 1 cm long, petal tube to 0.5 cm; […]
Houstonia caerulea  (Hedyotis c.) azure bluets Rubiaceae HECA; R (DeCandido 2001); - Houstonia caerulea is a very small, delicate winter annual or perennial herb, 5-10 cm tall in flower, winter rosettes forming mats a few cm wide, colonial by slender rhizomes.  Leaves opposite mostly basal, widest above middle, ca 1 cm long, stalk ca 1 cm; stem leaves reduced, nearly stalkless (subsessile).  Flowers pale blue with yellow eye, to […]
Hydrastis canadensis gold-seal Ranunculaceae HYCA; Bx, vc; -    Hydrastis canadensis is a perennial herb to 50 cm, slowly colonial from a knotty rhizome, stem hairy, sap yellow.  Leaves, one basal, two alternate stem leaves, to 25 cm after flowers bloom; broadly heart-shaped, deeply 5-lobed, lobe tips pointed, veins palmate, base lobed, margins coarsely double-toothed.  Flowers greenish-white, solitary, no petals, 3 sepals deciduous when flower […]
Hydrocotyle ranunculoides water pennywort Apiaceae R, ml (Zihao Wang); - Hydrocotyle ranunculoides is a small perennial aquatic herb, stem slender, mostly prostrate, rooting at nodes. Forming mats of leaves on water surface. Leaves round, kidney-shaped (reniform) or shield-shaped with stalk attached to center od leaf underside (peltate). Stipules scale-like. Flowers white, small in small clusters or single. Fruit dry, flattened side-to-side, rounded in outline (orbicular […]
Hydrophyllum virginianum Virginia waterleaf Hydrophyllaceae HYVI; R, eb, w; -     Hydrophyllum virginianum is a perennial herb, 30-80 cm (usually low, sprawling); colonial from a rhizome; stems finely hairy.  Leaves alternate, 10-20 cm long, and about as wide, pinnately 5-7 parted, irregularly lobed, margin toothed, petiole base enfolds stem, new leaves produced in late fall after leaf drop (Brundrett and Kendrick 1988).  Flowers pale violet to white, […]
Hylotelephium telephium subsp. telephium (Sedum purpureum; S. telephium) live forever Crassulaceae SEPU*; Bx, pb, Q, iw; R; -   Hylotelephium telephium subsp. telephium is a perennial herb, colonial from tuberous, white roots, stems pale, waxy green, branched, ringed by old leaf scars.  Leaves opposite or alternate, succulent, to 8 x 3 cm, becoming smaller upwards, dull, pale, waxy green, elliptic, tip blunt, base tapered to stem, no stalk, margin coarsely blunt-toothed to entire.  Flowers deep […]
Hypericum canadense Canada St. Johnswort Clusiaceae HYCA; Bx, vc; Q, j (Stalter and Lamont 2002); R, ah, gr, k; -     Hypericum canadense is an annual, or perennial herb from short, leafy basal shoots, stems 10-60 cm tall.  Leaves opposite, narrow, widest above middle, 1-4 cm long, 0.1-0.4 cm wide, speckled with minute, translucent glands (hold up to light), tip blunt, base tapered, 1-veined.  Flowers yellow, 5-parted, small, petals 0.3 cm long, sepals 0.3-0.5 cm long, stamens 12-22, […]
Hypericum ellipticum pale St. John’s-wort Clusiaceae HYEL; Bx, pb (DeCandido 2001); -    Hypericum ellipticum is an aquatic perennial herb 20-50 cm, colonial from rhizomes, stems mostly unbranched below inflorescence.  Leaves opposite, elliptic, 1-3 cm long to ca 1.5 cm wide, blunt at both ends, speckled with minute, translucent glands (hold up to light).  Flowers bright yellow, 5-parted, petals 0.5-0.7 cm long, sepals to 0.6 cm long, stamens numerous, […]
Hypericum gentianoides orange grass Clusiaceae HYGE; Bx, pb (DeCandido 2001); -    Hypericum gentianoides is an annual herb to 50 cm, stems slender with numerous, opposite thread-like wiry branches.  Leaves opposite, scale-like, to 0.4 cm, appressed to stems.  Flowers yellow, tiny, in axils, scattered along branches, petals to 0.4 cm, sepals to 0.2 cm.  Fruit a dry capsule, cone-shaped, to 0.7 cm; blooms and fruits July-Oct.  Wetland status: UPL.  […]
Hypericum Genus St. John’s-wort Clusiaceae -    Hypericum is a genus of herbs (ours), annual or perennial.  Leaves opposite, entire, usually sprinkled with tiny glandular dots.  Flowers yellow, 4-5 parted, radially symmetrical, petals with edges overlapping (convolute), sepals persistent, often unequal, stamens 5-numerous, ovary superior, 2-5 parted, with as many styles; inflorescence usually branched with topmost flowers blooming first (cymose).  Fruit often red at first, […]
Hypericum mutilum dwarf St. John’s-wort Clusiaceae HYMU; Bx, pb (DeCandido 2001); Q, cu, j, ri; R (DeCandido 2001); -    Hypericum mutilum is a perennial (sometimes an annual) herb, 10-80 cm tall, much branched above.  Leaves opposite, egg- to lance shaped, 1-4 cm long, tip blunt, base broad, rounded, partially clasping stem, surface speckled with minute, translucent glands (hold up to light), veins 3-5.  Flowers yellow, petals 0.2 cm long cm, sepals persistent about as long […]
Hypericum perforatum common St. John’s-wort; Klamath weed Clusiaceae HYPE*; Bx, g, nb, pb; Q, f, j, wl; R, c, is, lp; -      Hypericum perforatum is a perennial, 3 herb (Pooter et al. 1990), 40-80 cm tall, colonial (in some parts of the USA) from rhizomes, branches numerous, upturned, opposite, leafy, each pair at right angles to next (decussate) many winter-green, leafy shoots at base, often mat-forming, stems sharply ridged below leaf bases.  Leaves opposite, simple, stalkless, linear-oblong, 2-4 […]
Hypericum punctatum spotted St. Johnswort Clusiaceae HYPU; Bx, pb (DeCandido 2001); NY, bl (Stalter and Tang 2002); Q, tl; R, hs; -     Hypericum punctatum is a perennial herb, erect, 0.5-1 m tall, few branches below inflorescence  Leaves opposite, sessile, blade 4-6 long, over 1 cm wide, oblong, tip and base blunt, surface marked with tiny black and clear dots.  Flowers yellow, 0.8-1.5 cm wide, petals 5, 0.8-1.5 cm long, surface densely covered with amber dots, often persistent wide, […]
Hypochaeris radicata  (Hypochoeris r.) cat’s ear Asteraceae HYRA*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); Q, cu, ft, j; K (DeCandido 2001); R, lp; -     Hypochaeris radicata is a perennial herb from a root crown, roots often enlarged, fleshy; sap milky, most parts hairy, flowering stem 15-60 cm, stiff, wiry, large plants branched above.  Leaves mostly in an overwintering basal rosette, 3-35 cm long, 0.5-7 cm wide, lance-shaped, widest above middle, broadly toothed to divided, surface roughly hairy.  Flowers yellow, all […]
Hypoxis hirsuta yellow stargrass Liliaceae HYHI; Palisades Park, NJ; Bx, pb (DeCandido 2001, Z. Wang 2017); Q, cu (Greller 1977, 1979, 1985), j (Stalter and Lamont 2002); R (DeCandido 2001); -      Hypoxis hirsuta is a perennial monocotyledon herb from a corm, about 2 cm wide.  Leaves all basal, grass-like, to 60 long, 0.2-1 cm wide, finely hairy; flowering stems very slender to 40 cm tall.  Flowers yellow, star-shaped to 2 cm wide; inflorescence of 2-6 flowers at top of stem; blooms May-July.  Fruit dry, pod to 0.6 […]
Impatiens capensis  (I. biflora) jewelweed; touch-me-not Balsaminaceae IMCA; Bx, bg, br, bz, pb, rd, sf, up, vc; NY, ct, hb; Q, a, c, cr, cu, u; K, p; R, ah, ar, bd, bk, bm, c, ca, cp, cs, fk, gr, gb, h, is, js, lp, lt, mc, o, pm, r, rw, sb, sv, t, v, w, wp, wt;  -    Impatiens capensis is an annual herb, 0.5-1. 5 m tall, nodes swollen, stems branched, juicy, rather translucent, waxy-pale green, internodes hollow; roots associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves alternate, stalk to ca 5 cm long (Yatskievych 2006), blade 3-10 cm long, soft textured, waxy-pale below, margin toothed.  Flowers of two kinds, those of […]
Impatiens pallida pale jewelweed Balsaminaceae IMPA; Bx, br, pb, vc; -     Impatiens pallida is an annual herb to 1.5 m, much like I. capensis but mostly larger and much less common, stem branched, nodes swollen, juicy, rather translucent, waxy-pale green, internodes hollow.  Leaves alternate, to 10 cm long, soft, toothed, waxy-pale below.  Flowers pale yellow, sparsely dotted with reddish brown, conical, bilaterally symmetrical (as in I. capenisis), to 4 cm long, sepal […]
Iris prismatica slender blue flag Iridaceae IRPR; Bx, pb; R, gr, t, wp; -    Iris prismatica isa perennial monocotyledon, colonial from a slender, creeping rhizome at surface of soil and slightly buried stolons 0.2-0.5 cm diameter, stolon tips sprouting new plants, which give rise to flowering stems the following season.  Leaves mostly basal, in tufts from stolon tips, linear 50-70 cm long, 0.3-0.7 cm wide, bases reddish, 1-4 along […]
Iris pseudacorus yellow iris  Iridaceae IRPS*; Bx, br, bz, cm, pb; NY, ct; Q, u; R, gr, mls; -   Iris pseudacorus is a perennial monocotyledon 50 cm to 1 m, aggressively colonial from pink-fleshed rhizomes 2-3 cm wide, flowering stem shorter than or equal to leaves.  Leaves basal, linear, stiff, erect in fan-shaped arrangement, 0.4–1.0 cm long, 2–3 cm wide, midrib region thickened, apparently wider than those of I. versicolor and more persistent in autumn, veins parallel; […]
Iris versicolor large blue flag Iridaceae IRVE; Bx, vc; NY, ct; Q, u, ri, wl; R, gb, h, is, t; -     Perennial monocotyledon, stems 20-80 cm from thick rhizomes, buried or barely at soil surface, often forming large clumps.  Leaves mostly basal, 0.2-1 m long, 0.5-3 cm wide, in fan-shaped arrangement, broadly linear, about as long as flowering stem, usually purple at base, stem leaves few; flowers 6-8 cm wide.  Flowers blue-violet with darker veins, 6-8 cm […]
Isotria verticillata larger whorled pogonia Orchidaceae ISVE; R, ev, h; -    Isotria verticillata is a perennial monocotyledon herb from fleshy roots, colonial, stems 20-40 cm tall.  Leaves 5, 3-8 cm long, in one whorl, on upper stem below flower, oblong.  Flower greenish-brown to purplish, with conspicuous lines, fragrant, bilaterally symmetrical, thin, spidery-appearing, sepals 3, linear-elongate, 3.5-6.5 cm long, lateral petals wider, 1.5-2.5 cm long, lip about 2 […]
Justicia americana water-willow Acanthaceae JUAM; R (DeCandido 2001); -    Justicia americana is a perennial herb, colonial from rhizomes, stems 50-100 cm tall, mostly unbranched, rooting at lower nodes.  Leaves opposite, 8-16 cm long, 0.8-2.5 cm wide, linear to lance-shaped, pointed at both ends.  Flowers pale violet to white with purple markings on lower lip, bilaterally symmetrical, tubular, about 1 cm long, 2- lipped, lips about […]
Kochia scoparia  (Bassia s.) summer cypress; Mexican fireweed Chenopodiaceae KOSC*; Bx, pb (DeCandido 2001); Q, lk; R, c, hs; -     Kochia scoparia is an annual, C4 herb (Jacobs 2001), erect, to 1.5 m tall, pyramidal, bushy-branched, densely leafy, usually densely, finely hairy above, stems often reddish.  Leaves alternate, no stalk, blade lance-shaped, to linear, to 5 cm long, becoming much shorter upwards and in flowering stalks, becoming bright red in Autumn.  Flowers green, inconspicuous, to 0.3 cm, […]
Kosteletzkya pentacarpos  (K. virginica) seashore mallow Malvaceae KOVI; Bx, pb (DeCandido 2001); -    Kosteletzkya  pentacarpos is a perennial herb to 1 m tall, stems rough-hairy.  Leaves alternate, 6-15 cm long, egg-shaped, with two lateral lobes, tip pointed, base lobed, margin coarsely toothed, dull gray-green, rough-hairy, upper leaves becoming bract-like, lance-shaped.  Flowers pink, showy, petals 2-4.5 cm long, 3 cm wide, egg-shaped, calyx to 1.3 cm, accompanied by small, linear […]
Krigia biflora orange dwarf dandelion Asteraceae KRBI; Bx, pb (DeCandido 2001); -    Krigia biflora is a perennial herb 20-80 cm tall, somewhat waxy-pale, branched near middle.  Leaves mostly basal, 4-25 cm long including stalk, 1-5 cm wide, elliptic to widest above middle, margin sometimes toothed or divided, stem leaves few, small, stalkless, clasping stem, the uppermost almost opposite inflorescence stalks.  Flowers orange, all rays, showy, heads about 3 […]
Krigia virginica Virginia dwarf dandelion Asteraceae KRVI; Bx, pb (DeCandido 2001), vc (Z. Wang 2015); Q, j (Stalter and Lamont 2002); K, p;  -    Krigia virginica is a slender annual herb, 5-30 cm tall, stem hairy, branched or simple, leafless or leafy near base.  Leaves mostly basal, 1.5-12 cm long, 0.1-1.2 cm wide, linear to egg-shaped or widest above middle, sometimes toothed or pinnately divided, sometimes hairy.  Flowers yellow, all rays, heads about 1 cm wide, bracteate base 0.4-0.7 cm […]
Lactuca biennis tall blue lettuce Asteraceae LABI; Bx pb, wv (Yost et al. 1991); R, gb; -     Lactuca biennis is an annual or biennial herb, (NYS S1, E) large, 60 cm to 3 m tall, sap milky.  Leaves alternate, 10-40 cm long, 4-20 cm wide, irregularly pinnately divided, base lobed, margin toothed, upper leaves stalkless.  Flowers blue-white, all rays, heads with 15-34 flowers, bracteate base about 1 cm tall in fruit; heads crowded […]
Lactuca canadensis wild lettuce Asteraceae LACA2; Bx, pb, sd, sf; NY, hb; Q, a, cu, f, j; K, pl; R, cl, d, hs, js, pr, ro, sv, wp; -    Lactuca canadensis is an annual or biennial herb, 0.3 -2.5 m tall, sap milky, white to tan, stem leafy, often waxy-pale (glaucous).  Leaves alternate, entire to lobed, margin toothed or lobed to entire, base narrowed, or sometimes clasping stem or with pointed lobes, blade 10-35 cm long, 1.5-12 cm wide, leaves of basal rosette to […]
Lactuca floridana false lettuce Asteraceae LAFL; Bx, pb (DeCandido 2001); -     Lactuca floridana is an annual or biennial herb (NYS Rare SH, U), large, 50 cm to 2 m tall, sap milky.  Leaves alternate, stalked, blade 8-30 cm long, 2.5-20 cm wide, elliptic, irregularly lobed, lobes pointed, toothed.  Flowers blue, all rays (ligulate), 11-17 per head, bracteate base of head 0.9-1.4 cm tall in fruit; inflorescence large, […]
Lactuca serriola  (L. scariola) prickly lettuce Asteraceae LASE*; Bx, cm, pb, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002); Q, a, cu (Greller 1985), j, lk; K (DeCandido 2001); R, cs, hs, pr; -      Lactuca serriola is an annual or biennial herb, 0.30-1.5 m tall, from a leafy rosette, flowering stem often prickly below, sap milky.  Leaves all basal at first, stem leaves alternate, 5-25 cm long narrow, lobed or unlobed, spiny toothed, midrib prickly below, twisted at base, clasping stem, pale dull blue-green, midrib whitish, upper leaves […]
Lamium amplexicaule henbit dead-nettle Lamiaceae LAAM*; NY, bl (Stalter and Tang 2002); Q, j (Stalter and Lamont 2002); R, hs;  -    Lamium amplexicaule is an annual or winter annual herb 10-40 cm tall, from a taproot, branched at base, several weak stems, bases often reclining (decumbent).  Leaves opposite, those of lower stem long-stalked, blade to 1.5 cm long and wide, rounded to kidney-shaped, surface puckered by impressed veins, margin coarsely round-toothed to lobed, leaves below flower […]
Lamium purpureum red dead nettle Lamiaceae LAPU*; Bx, pb (DeCandido 2001), wv (Yost et al. 1991); NY, ct, hb; Q (DeCandido 2001); K, p; R, hs; -     Lamium purpureum is a winter annual herb 10-40 cm tall, usually branched from base, lower part of stem often prostrate, stem 4-sided, usually purplish, lower internodes elongate.  Leaves opposite, stalked, blade 0.7-3 cm long, heart-shaped, surface dull, finely bristly, puckered by sharply impressed veins, margin toothed; the upper blades usually purplish, crowded near top of […]
Laportea canadensis wood nettle Urticaceae  LACA3; Bx, br, bz; R, gb; -    Laportea canadensis is a perennial herb, 0.5-1 m tall, stems armed with stinging hairs, roots fibrous, often colonial from rhizomes, associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves alternate, stalked, blade 8-15 cm long, broadly egg-shaped, hairy, veins palmate at base, pinnate above, deeply impressed, tip long-pointed, margin coarsely toothed.  Flowers greenish, tiny, monoecious, male […]
Lapsana communis  nipplewort Asteraceae LACO*; Bx, pb, vc, sd, wv (Yost et al. 1991); Q, a; R, mls; -    Lapsana communis is an annual herb, 15-150 cm tall, sap milky (sometimes very slightly), often hairy.  Leaves alternate, lower leaves stalked, sometimes lobed at base, blade 2.5-10 cm long, 2-7 cm wide, narrowed and smaller upwards, leaves of inflorescence often narrowly lance-shaped.  Flowers yellow, 8-15 all rays, dandelion-like, basal bracts of head smooth, subequal, keeled, bracteate […]
Lechea maritima beach pinweed Cistaceae LEMA; Q, bp, tl; K, gt, j, pl; R, gw; -    Lechea maritima is a perennial herb, 10-40 cm tall from a woody taproot to 10 cm long (Barringer 2004), stems pale, whitish, fine-hairy, producing over-wintering leafy basal rosette in Autumn; (Barringer 2004).  Leaves of basal shoots whorled, 0.5-1.2 cm long, 0.1-0.5 cm wide, lance-shaped, pointed at both ends, pale-hairy below, stem leaves 0.7-2.5 cm long, […]
Lechea mucronata  (L. villosa) hairy pinweed Cistaceae LEMU; Bx, pb (DeCandido 2001); R, cp;  -     Lechea mucronata is a perennial or biennial herb from a woody taproot, 10-60 cm tall, hairy, flowering stem solitary or few, branched above, brownish-purple, overwintering basal shoots evergreen, prostrate, branching, to 10 cm long, densely hairy.  Leaves opposite or whorled, those of basal shoots 0.8-1.5 cm, elliptic, leathery, crowded, those of flowering stem lance-shaped, 1-3 […]
Lechea racemulosa Illinois pinweed Cistaceae LERA; Bx, pb (DeCandido 2001); R, gr; -     Lechea racemulosa is a perennial herb, to 40 cm tall, thinly hairy, branched above.  Leaves alternate, very small, bright green, basal leaves oblong-elliptic, to 0.4 cm long 0.15 cm wide, stem leaves much narrower.  Flowers green-brown, about 0.2 cm, sepals 5, 2 outer sepals shorter than or about as long as 3 inner sepals, no petals; […]
Lemna minor lesser duckweed Lemnaceae LEMI; Bx, pb, sf, vc; NY, ct; Q, a, cu, j; R, ar, lp, bm, gb, hs, js, mls, w, wp; -    Lemna minor is an annual, monocotyledon, free floating, tiny, green disk-shaped plants with a single, unbranched root from center of underside, body elliptic to egg-shaped, 0.2-0.6 cm wide, budding from edges, often 2-5 together with overlapping, fused edges, body flat or slightly convex on one or both sides, appearing rather thick (use lens), bright […]
Leonurus cardiaca motherwort Lamiaceae LECA*; Bx, bs, pb, sm, wv (Yost et al. 1991); Q, a; K, p; R, c; -     Leonurus cardiaca is a perennial herb, colonial from rhizomes with fibrous roots, stems to 1.5 m tall, from an overwintering basal rosette (Levine 1995; Yatskievych 2006); stems, stout, erect, branched, ribbed or strongly angled, usually clustered.  Leaves opposite, stalks to 13 cm long, blade to 15 cm long, 12 cm wide, deeply 3-lobed and toothed, […]
Lepidium campestre field cress Brassicaceae LECA2*; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont 2002); K, m; R, bm, js; -     Lepidium campestre is an annual or biennial herb, from a tap root, softly hairy, to 50 cm tall.  Leaves alternate, basal leaves long, narrow, widest above middle, sometimes lobed, stalked, stem leaves numerous, overlapping, stalkless, lance-shaped, to 4 cm long, base lobed, clasping stem, margin toothed.  Flowers white, petals 4, ca 0.2 cm long, stamens 6, […]
Lepidium densiflorum prairie pepper-grass Brassicaceae LEDE; Bx, br; R, d; -     Lepidium densiflorum is an annual or biennial herb, 20-50 cm tall.  Leaves alternate, initially in a basal rosette, 4-7 cm long, coarsely toothed to pinnately lobed, margins toothed, stem leaves 1-3 cm long, linear, usually entire (USDA Forest Service 2006).  Flowers white, tiny, petals 4, shorter than sepals or none, stamens 2; inflorescence of crowded racemes […]
Lepidium Genus pepperweed Brassicaceae -    Lepidium is a genus of herbs, ours mostly annuals or biennials.  Leaves alternate, often pinnately divided or toothed, initially in a basal rosette, stem leaves usually smaller than rosette leaves, often stalkless or clasping stem.  Flowers white to greenish, radially symmetrical, small, petals 4 or lacking, sepals 4, stamens 2-6, ovary superior, 2-parted one ovule per […]
Lepidium latifolium perennial pepperweed Brassicaceae LELA*; NY, iw; -     Lepidium latifolium is a perennial herb, 1-2 m tall, colonial from rhizomes, plant usually waxy blue-green, mostly hairless.  Leaves alternate, narrow, basal leaves long-stalked, blade to 30 cm long, 8 cm wide, margins toothed, stem leaves stalkless, blade smaller, 1-4 cm wide, margins toothed to entire.  Flowers white, small, petals 4, 0.1 cm long, spatula-shaped; inflorescences […]
Lepidium ruderale stinking pepperweed Brassicaceae LERU*; Bx, pb (DeCandido 2001); -    Lepidium ruderale is an annual or biennial herb to 50 cm tall, unpleasant odor, minutely hairy.  Leaves alternate, basal leaves twice pinnately lobed, lower stem leaves pinnately divided, upper leaves toothed or entire, tip blunt.  Flowers white, petals 4, tiny, stamens 2; blooms and fruits May-Sept.  Fruit dry, capsule egg-shaped, to 0.3 cm, notched at tip.  Wetland […]
Lepidium virginicum poor-man’s pepper Brassicaceae LEVI2; Bx, br, cn, pb, sn, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, rr; Q, a, f, fr, ft, i, j, tl; K, fl, fs, pl; R, al, bk, c, d, fk, hs, is, jl, mls, pr, se, sv, wp; -     Lepidium virginicum is an annual or biennial, C3 herb (Ludwig et al. 2010), 10-50 cm tall, taprooted, base of stem sometimes purple, simple to freely branched from upper leaf axils.  Leaves alternate, those of basal rosette 2-10 cm long, 0.5-2 cm wide, inversely lance-shaped (oblanceolate), margin sharply toothed to deeply lobed; stem leaves narrow, small, tip […]
Lespedeza capitata round-headed bush-clover Fabaceae LECA3; BX vc (Burg 2015); Q, a, i, j; K (DeCandido 2001); R, c, ca, cp, gb, jw, lp, sm, sv, ty; -     Lespedeza capitata is a perennial herb, 0.6-1.5 m tall, erect, stems stiff, rather stout sparsely branched above or simple, densely hairy, often appearing silvery; roots with some ability to fix nitrogen (USDA, NRCS 2006); stipules linear (Yatskievych 2006).  Leaves alternate, stalk 0.2-0.5 cm, shorter than stalk of middle leaflet, blade 3-parted, leaflets 1.5-5 cm long, […]
Lespedeza cuneata Chinese Lespedeza Fabaceae  LECU*; Q, i, j;  -   Lespedeza cuneata is a woody perennial herb, to 1.5 m tall, erect, stems finely ribbed, branches numerous, elongate, wand-like, densely appressed hairs makes plant appear gray-green.  Leaves alternate, 3-parted, larger leaflets to 2.5 cm long, 0.4 cm wide, tip rounded with abrupt, small point, base narrowed to stalk 0.5 cm, dull dark green above, finely […]
Lespedeza Genus lespedeza Fabaceae (Papilionoideae) -    Lespedeza is a genus of perennial, sometimes woody, herbs.  Leaves alternate, 3-parted, numerous, margins entire; stipules persistent, linear to lance-shaped.  Flowers purple to pale dull yellow, bilaterally symmetrical, pea-flower-shaped, small; corolla parts and stamens fused to a basal saucer-like hypanthium (perigynous); top petal (standard) rounded, base narrowed (clawed), side petals (wings) oblong, clawed, fused to lower […]
Lespedeza hirta hairy bush clover Fabaceae LEHI; BX, pb (DeCandido 2001); -     Lespedeza hirta is a perennial herb, to 1.5 m tall, stems erect, stout, hairy.  Leaves alternate, 3-parted, stalk 0.5-2 cm, leaflets to 6 cm long, 4 cm wide, oval to almost linear, hairy below, stalk of middle leaflet to 1 cm long, hairy, thick.  Flowers yellowish-white, base purple, 0.6-0.9 cm long, pea-flower-shaped, calyx hairy to 1 […]
Lespedeza intermedia  (L. frutescens) wandlike bush clover; shrubby b. c. Fabaceae LEIN; BX, pb (DeCandido 2001); NY, iw; R, ca; -     Lespedeza intermedia is a perennial herb, usually less than 1 m tall, erect, hairy to almost smooth, slender, branched above, branches slender, elongate.  Leaves alternate, leaf stalks to 3 cm long, blade 3-parted, leaflets oval to oblong, to 4 cm long, 3 cm wide; appressed-hairy below. Flowers of two kinds: those with purple petals, to 0.3 […]
Lespedeza procumbens trailing bush-clover Fabaceae LEPR; Bx, pb (DeCandido 2001); -    Lespedeza procumbens is a perennial herb, 0.3-1.2 m long, stems hairy, trailing or reclining, densely, soft-hairy.  Leaves alternate, 3-parted, leaf stalks shorter than leaflets, leaflets 0.8-2.5 cm long, to 1 cm wide, egg-shaped, to elliptic, tip and base rounded, appressed hairy at least below.  Flowers of two kinds: those with purple petals, pea-flower-shaped, to 0.8 cm, […]
Lespedeza stuevei velvety lespedeza Fabaceae LEST; R (DeCandido 2001); -     Lespedeza stuevei is a perennial herb 0.3-1.2 m tall, stems softly hairy, erect, simple or with wand-like branches.  Leaves alternate, crowded, stalks short, blade 3-parted, leaflets oblong or widest above middle, hairy on both sides, larger leaflets of main stem 1-3 cm long, to about 1 cm wide (Radford et al. 1968).  Flowers of two kinds: […]
Lespedeza violacea violet lespedeza Fabaceae LEVI3; R (DeCandido 2001); -     Lespedeza violacea is a perennial herb, 30-80 cm tall, erect, much branched, branches long, more-or-less hairless, sparsely leafy, stipules linear to 0.6 cm long.  Leaves alternate, stalks long, blade 3-parted, leaflets elliptic, 1-5 cm long, to 2.2 cm wide, appressed-hairy below.  Flowers of two kinds: those with purple petals, 0.6-1 cm long, keel longer than wings […]
Lespedeza virginica slender bush clover Fabaceae   LEVI; Bx, pb(DeCandido 2001); Q, i, j (Stalter and Lamont 2002; R (DeCandido 2001);  - Lespedeza virginica is a perennial herb 0.3-1 m tall (Radford et al. 1968), sparsely slender-branched, somewhat appressed-hairy; stipules linear, brownish.  Leaves alternate, crowded, 3-parted, leaflets linear to narrowly oblong, 0.6-3 cm long, ascending, to about 0.5 cm wide, finely appressed hairy on both sides.  Flowers of two kinds: those with rose-purple petals, 0.5-0.7 cm long, pea-flower-shaped, wings […]
Liatris scariosa var. novae-angliae  (L. borealis) northern blazing star Asteraceae LISC; R (DeCandido 2001); -    Liatris scariosa var. novae-angliae  is a perennial herb 30-80 cm tall, from a thick rounded corm-like rootstock.  Leaves alternate, lowest long-stalked, bade 10-35 cm long, 1-2 cm wide, elliptic, pointed at both ends, margins entire, smaller upwards.  Flowers pink-purple, 25-80 per head, all disk flowers, bracteate base (involucre) of head 0.9-1.7 cm long, bracts rounded, overlapping, […]
Lilium canadense Canada lily; wild yellow lily Liliaceae  LICA; Bx, pb (DeCandido 2001); R (DeCandido 2001); -   Lilium canadense is a perennial, monocotyledon  herb from a bulb; stem erect 60 cm to 1.5 m tall, smooth.  Leaves stalkless, blades in 6-11 whorls of 4-12, but the lowest and uppermost often alternate, larger blades lance-shaped, 8-15 cm long, 0.8-2 cm wide, rough textured on margins and veins below.  Flowers yellow to yellow-orange, with purple […]
Lilium superbum Turk’s cap lily Liliaceae LISU; Bx, pb (DeCandido 2001); Q, cu; R, ah, h, cn, ok, ro, sp, sv, t; -     Lilium superbum is a perennial  monocotyledon herb, from a bulb; stem to 2.5 m, sparingly colonial from bulb offsets.  Leaves stalkless, upper leaves in whorls of 5-20, 8-18 cm long, 1-3 cm wide, lower leaves alternate blades narrowly lance-shaped, pointed at both ends, smooth or with small bumps along margin.  Flowers orange, with dark freckles, green […]
Limonium carolinianum sea lavender Plumbaginaceae LICA3; Bx, pb (DeCandido 2001); Q, dp, fr, j; K, fl, m, pl; R, sm, v; -     Limonium carolinianum is a perennial herb from a thick root stock, and horizontal rhizomes (Flora of North America 1993+; but see USDA, NRCS 2006), plant 20- 70 cm tall (usually less), widely, densely branching, rather flat-topped.  Leaves alternate, all basal, stalk 3-15 cm long, blade 4-17 cm long, 1-4 cm wide, elliptic to lance-shaped, surface […]
Linaria vulgaris butter-and-eggs; yellow toadflax Scrophulariaceae LIVU2*;Bx, nb, pb; NY, hb; Q, a, cu, j, ri, tl, wl; K, fl; R, c, cp, d, jl, mls, sv, wp; -     Linaria vulgaris is a perennial herb, colonial from buds along creeping roots, tap root may reach 1 m deep, reported to be associated with a vesicular-arbuscular mycorrhizae; sprouting from root buds starts in April, apparently able to fix nitrogen, (Saner et al. 1995). To 80 cm tall, often branched above.  Leaves alternate to almost opposite, […]
Lindernia dubia false pimpernel Scrophulariaceae LIDU; Bx, sf; Q, cu (Greller 1977); R, bk, mls, t; -     Lindernia dubia is an annual herb, 5- 20 cm tall, branching, stem often 4-sided.  Leaves opposite, to 3 cm long, oblong to elliptic, stalkless, tip blunt, base rounded, margin entire to remotely toothed.  Flowers pale bluish, bilaterally symmetrical, 0.5-1cm long, 2-lipped, upper lip 2-lobed, much narrower than 3-lobed lower lip, sepals narrow, 0.3-0.4 cm, fused at […]
Linum medium yellow flax Linaceae LIME; R (DeCandido 2001, possibly extinct); -     Linum medium is a perennial herb 20-70 cm tall, unbranched up to inflorescence, plant waxy, pale green.  Leaves stalkless (sessile), opposite below, 1-2.5 cm long, 0.2-0.5 cm wide, smaller above, narrowly lance-shaped or inversely lance-shaped (oblanceolate), tips pointed, veins obscure.  Flowers yellow, radially symmetrical, petals 5, 0.4-0.8 cm long, heart-shaped, widest at rounded to notched tip, […]
Linum usitatissimum flax; linseed Linaceae LIUT*; Bx, pb (DeCandido 2001); -    Linum usitatissimum is an annual herb to 1 m, several stems, branched above.  Leaves sessile, alternate, to 3.5 cm long, 3-veined, narrowly lance-shaped.  Flowers blue, radially symmetrical, petals 5, to 2.3 cm long, tip blunt, base narrowed on long stalks, May-July.  Fruit a dry, rounded capsule to 0.9 cm wide, opening into 10 segments to release one […]
Liparis loeselii bog twayblade; yellow twayblade; fen orchid Orchidaceae LILO; Q, (Dave Taft 2016, one plant); R (one site, if still extant, DeCandido 2001; not found in 2016); -    Liparis loeselii is a perennial monocotyledon herb, 10-25 cm tall from a corm. Leaves basal, two, elliptic, entire, 5-15 cm long, 2-3 cm wide, slightly folded along midrib.  Flowers yellow-green, bilaterally symmetrical, sepals 3, linear, 0.5-0.6 cm, petals 2, linear, 0.5 cm, lip 0.5 cm much wider than sepals, broadly egg-shaped; inflorescence spike-like (raceme) with 2-12 […]
Lobelia cardinalis cardinal flower Campanulaceae LOCA; Bx, pb (DeCandido 2001); NY (DeCandido 2001); R, ah, h, t; -     Lobelia cardinalis is a perennial herb from basal offshoots (winter rosette), 50 to 150 (rarely) cm tall erect, stout, unbranched, fibrous rooted, usually hairy (Levine 1995), sap milky (Yatskievych 2006).  Leaves alternate, the lower stalks to 3 cm long, upper leaves becoming sessile, blade thin, narrow, 5-20 cm long, 2-5.5 cm wide, elliptic to lance-shaped […]
Lobelia inflata Indian-tobacco Campanulaceae LOIN; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R, sv; -   Lobelia inflata is an annual herb 15-100 cm tall, usually much branched, hairy, sap milky (Yatskievych 2006).  Leaves alternate, often overwintering as a rosette of dark green leaves; stalkless or almost so, blade 5-8 cm long, 1.5-3.5 cm wide, egg-shaped to widest above middle (obovate), hairy below, margin toothed.  Flowers pale blue to white, bilaterally symmetrical, […]
Lobelia siphilitica great lobelia Campanulaceae LOSI; Bx, pb (DeCandido 2001), sf (planted), wv (Yost et al. 1991); -     Lobelia siphilitica is a perennial herb by basal offshoots, 0.5-1.5 m. tall (usually shorter), stout, erect, mostly unbranched, sap milky (Radford et al. 1968).  Leaves alternate, stalkless, blade 5-12 cm long, 1-6 cm wide, elliptic, pointed at both ends, hairy above, margin irregularly toothed, upper leaves merging into floral bracts.  Flowers blue, to 3 cm long, […]
Lobularia maritima sweet alyssum Brassicaceae ALMA*; R, ot; -    Lobularia maritima is an annual or perennial herb to 30 cm tall, branched, inconspicuously hairy, stems slender, green.  Leaves alternate, narrow, widest above middle, larger ones 2-5 cm long, to 1 cm wide, tip pointed.  Flowers white to pale yellow, fragrant, 0.4 cm wide, petals 4, rounded and widest at top, base narrowed (clawed), sepals 4, […]
Lotus corniculatus bird’s-foot trefoil Fabaceae LOCO*; Bx, pb(DeCandido 2001); NY (DeCandido 2001); Q, i, j, wl; K (DeCandido 2001); R, cp, d, e, fk, k, t, ty, v, w; -     Lotus corniculatus is a short-lived perennial form a taproot up to 1 m long, colonial from sprouting buds on numerous lateral roots that form a fibrous mat. Can resprout from detached root segments. Stems multiple, often prostrate to reclining, to 60 cm, becoming woody, forming adventitious roots when in contact with soil, younger stems 4-sided (Turkington […]
Ludwigia alternifolia seed box Onagraceae LUAL; Bx, pb (DeCandido 2001); R, bd, gr; -     Ludwigia alternifolia is a perennial herb, 0.4-1.2 m tall, from clumps of fleshy-fibrous roots; stems slightly wing-angled (Radford et al. 1968), erect, branched, often reddish in sunny sites.  Leaves alternate, stalks 0-0.2 cm long, blade 5-10 cm long, to2 cm wide, lance-shaped, pointed at both ends, surface slightly rough from minute stiff bristles, secondary veins […]
Ludwigia palustris marsh-purslane Onagraceae LUPA; Bx, br, pb (DeCandido 2001); Q, cu, j, wl; R, gr, js, lp, t, w, wt; -     Ludwigia palustris is a perennial herb, small, floating or creeping, stems prostrate, colonial from stem fragments and rooting at nodes, stems 10-60 cm long (Radford et al. 1968), weak, often reddish in full sun.  Leaves opposite, stalk to 2.5 cm long, blade 0.5-3 cm long, 2 cm wide, elliptic to egg-shaped, tip pointed, base narrowed […]
Ludwigia sphaerocarpa round-pod water-primrose Onagraceae LUSP; R (DeCandido 2001); -     Ludwigia sphaerocarpa is a perennial herb to 1 m tall, colonial from stolons, freely branched above, often red in full sun.  Leaves alternate, stalk 0-0.2 cm long, blade 5-10 cm long, to 1.5 cm wide, lance-shaped to linear, pointed at both ends, leaves of inflorescence much smaller.  Flowers green, no petals, sepals 4 from rim of […]
Lunaria annua honesty Brassicaceae LUAN; Q, j (Stalter and Lamont 2002); R, rc; -    Lunaria annua is an annual herb to 1 m tall.  Leaves alternate above, opposite near base, stalk little to none, blade heart-shaped, coarsely toothed.  Flowers purple, showy, radially symmetrical, 2 cm wide, 4 petals; fragrant; attractive to bees and butterflies (Dave’s Garden 2007).  Fruit dry, circular, disks to 5 cm diameter, becoming silvery-papery, persistent into winter.  Wetland […]
Lupinus perennis wild blue lupine Fabaceae LUPE; R (DeCandido 2001); -     Lupinus perennis is a perennial herb 20-60 cm tall.  Leaves alternate, palmately compound, leaflets 7-11, 2-5 cm long, widest above middle oblanceolate).  Flowers usually blue, bilaterally symmetrical, pea-flower-shaped, top petal (standard) 1.2-1.6 cm long; inflorescence of racemes 10-20 cm long at top of stem.  Fruit dry, an oblong, flattened hairy pod 3-5 cm long. Seeds eaten by […]
Lychnis coronaria rose champion; mullein pink Caryophyllaceae LYCO*; Bx, pb ; Q (DeCandido 2001); R (DeCandido 2001);  -     Lychnis coronaria is a biennial or short-lived perennial herb 40-80 cm tall, usually with multiple stems from base, all parts softly, densely, white-wooly, usually branched above.  Leaves opposite, softly, densely white-wooly, basal leaves in a rosette, stalked, 5-10 cm long, 1-3 cm wide, stem leaves stalkless (sessile), 5-10 pairs, smaller.  Flowers red-purple, showy, petals 5, […]
Lycopersicon esculentum tomato Solanaceae LYES*; Bx, pb; NY, bl (Stalter and Tang 2002); R(DeCandido 2001); -     Lycopersicon esculentum is an annual herb, stems green, sprawling, freely branched, finely sticky-hairy, sap yellow-green, irritating with characteristic scent.  Leaves alternate, to 30 cm long, pinnate, irregularly lobed and toothed very variable.  Flowers yellow, to 1 cm wide, radially symmetrical (regular), 5 petals with pointed tips, anthers together around stigma in a central, cone-shaped cluster, ovary […]
Lycopus americanus water horehound Lamiaceae LYAM; Bx, pb (DeCandido 2001); NY, ct; Q, j, ri, wl; R, c, ca, e, gr, is, js, lp, sb, t, w, wp, wt; -     Lycopus americanus is a perennial herb 30-90 cm tall, stems 4-sided, colonial from long rhizomes, stems 4-angled.  Leaves opposite, short-stalked, blade lance-shaped, 3-8 cm long, 2-4 cm wide (Radford et al. 1968), mostly pointed at both ends, margin with large, irregular, often blunt-tipped teeth, teeth larger toward leaf base, sometimes lobed at base, surface sprinkled […]
Lycopus Genus bugleweed; water horehound Lamiaceae -     Lycopus is a genus of perennial herbs, 0.1-1 m tall, stems 4-sided, colonial from rhizomes or stolons, stems 4-sided, barely aromatic.  Leaves opposite, simple, margins prominently toothed to pinnately lobed.  Flowers white, small, tubular, petal lobes 5, nearly radially symmetrical, calyx tube sharply 5-toothed; stamens 2; ovary superior, 4-parted, stigma 2-lobed; inflorescence of numerous, dense clusters […]
Lycopus rubellus gypsy-wort Lamiaceae LYRU; Q, cu (Greller 1977, 1979, 1985); -    Lycopus rubellus is a perennial herb to 1.2 m, stems 4-sided, colonial, stems arising from overwintering tubers at the ends of rhizomes and stolons produced the previous year.  Leaves opposite, lance-shaped to elliptic to 10 cm long, 3 cm wide, tip pointed, margin sharply toothed, base tapered to stalk.  Flowers white, often with purple spots, to […]
Lycopus uniflorus northern bugleweed Lamiaceae LYUN; Bx, pb (DeCandido 2001); R, ah; -      Lycopus uniflorus is a perennial herb 20-100 cm tall, stems 4-sided, from tuber-bearing stolons, a single stem arising from each tuber the following year.  Leaves opposite, essentially stalkless (sessile), 2-6 cm long, 0.5-3 cm wide (Radford et al. 1968), lance-shaped, tapered at both ends, light green, margin with few coarse teeth.  Flowers white, corolla about […]
Lycopus virginicus Virginia bugleweed Lamiaceae LYVI; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R, is, w, wt;  -     Lycopus virginicus is a perennial herb, 20-80 cm tall, stems 4-sided, from slender underground stems (stolons), stems square with blunt angles, freely branched, usually finely hairy.  Leaves opposite, 5-12 cm long, 2-5 cm wide, egg- to lance-shaped, tip pointed, margin coarsely toothed to slightly below middle of blade, margin near base untoothed, concave, extending down […]
Lysimachia ciliata fringed loosestrife Primulaceae LYCI; Bx, br, pb, vc; R, c, cb, t; -     Lysimachia ciliata is a perennial herb, colonial from a rhizome, stems 4-sided erect 0.4-1.3 m tall, multiple from base of plant (Yatskievych 2006).  Leaves opposite, stalk 0.5-5 cm long, hairy-fringed(ciliate) the entire length, winter rosette leaves about 4.5 cm long, 4 cm wide, long-stalked, tip rounded, base lobed; stem leaves 4-14 cm long, 2-6 cm […]
Lysimachia Genus loosestrife Primulaceae -     Lysimachia is a genus of perennial herbs.  Leaves opposite or whorled, entire.  Flowers yellow, radially symmetrical, 5-parted, petals fused at base, lobes spreading, sepals fused at base; stamens 5, opposite petal lobes; ovary superior; inflorescence of racemes.  Fruit dry, a capsule, splitting open along sutures to release numerous triangular seeds (Radford et al. 1968).  Notes: Lysimachia comes […]
Lysimachia hybrida lance-leaved loosestrife Primulaceae LYHY; Q (DeCandido 2001); -     Lysimachia hybrida is a perennial herb, to 1 m tall, colonial from a freely branching rhizome; stems erect, much-branched.  Leaves of winter rosette stalkless, or nearly so, stem leaves opposite, stalk hairy-fringed (ciliate) mostly below the middle; blade narrowly lance-shaped, 4-10 cm long, 1-2 cm wide, flat, tip pointed, base rounded to tapered, margin entire.  […]
Lysimachia nummularia moneywort; creeping jenny Primulaceae LYNU*; Bx, pb (DeCandido 2001); Q, wl; R (DeCandido 2001); -    Lysimachia nummularia is a perennial herb, creeping, mat-forming, rooting at nodes.  Leaves opposite, semi-evergreen, stalks 0.1-0.5 cm long (Radford et al. 1968), blade 1-2.5 cm long, rounded to broadly heart-shaped, surface sprinkled with tiny depressed dots.  Flowers yellow, dotted with dark red, radially symmetrical, 2-3 cm wide, petal lobes 1-1.5 cm long, calyx lobes leaf-like to […]
Lysimachia quadrifolia whorled loosestrife Primulaceae LYQU; Bx, pb, vc, wv (Yost et al. 1991); NY, iw; Q, cu, f, j; R, d, e, ev, cb, cl, d, gb, gr, h, k, lp, mm, sm, sv, t, ty, w; -    Lysimachia quadrifolia is a perennial herb, sparingly colonial from a 50 cm rhizome, roots associated with vesicular-arbuscular endomycorrhizal fungi (Berliner and Torrey 1989); stems erect, 0.3-1 m tall, finely hairy, usually simple, occasionally branched above.  Leaves usually in whorls of 3-6, usually 4, usually stalkless (sessile), blade 3-8 cm long, 0.2-0.7 cm wide, lance-shaped, tip […]
Lysimachia terrestris swamp candles Primulaceae LYTE; Bx, pb (DeCandido 2001); R, t, wp; -    Lysimachia terrestris is a perennial herb 40-80 cm tall, stem bluntly 4-sided, hairless, branched above, leaf scars leaving bamboo-like joints around stem; small, succulent bud-like bulblets form late in season in some leaf axes, often reddish, dropping to ground and forming new plants the following season.  Leaves opposite to subopposite, stalk short to none, blade […]
Lysimachia vulgaris garden loosestrife Primulaceae LYVU*; R (DeCandido 2001); -    Lysimachia vulgaris is a perennial C3 herb (Pooter et al. 1990), to 1 m tall, colonial from rhizomes 40-80 cm long, stems softly sticky-hairy.  Leaves opposite or whorled, 7-12 cm long, surface sprinkled with tiny dots, softly hairy below, lance-shaped, to 13 x4 cm, tip long-pointed, softly-hairy below.  Flowers yellow, to 2.5 cm wide, regular, petal lobes […]
Lythrum alatum winged loosestrife Lythraceae LYAL; Bx, pb (DeCandido 2001); R (DeCandido 2001); -     Lythrum alatum is a perennial herb 40-80 cm tall, erect, branches wand-like, stem 4-angled.  Leaves mostly alternate, opposite on lower stem, below branches, stalkless (sessile), blade to 4 cm long ca 1 cm wide, narrowly lance-shaped to elliptic, tip pointed, base rounded to slightly lobed, thick, surface dark green, crowded along branches, reduced to bracts […]
Lythrum hyssopifolia hyssop loosestrife Lythraceae LYHY*; R (DeCandido 2001); -      Lythrum hyssopifolia is an annual herb 10-60 cm tall, pale green, stem 4-angled.  Leaves mostly alternate, stalkless, blade 1-3 cm long, 0.1-0.7 cm wide, linear to elliptic.  Flowers pale purple, radially symmetrical, petals 4-6, 0.2-0.3 cm long, wedge-shaped (cuneate); calyx tubular, lobes 4-6, short; appendages between calyx lobes longer than lobes; stamens 4-6, shorter than […]
Lythrum salicaria purple loosestrife Lythraceae LYSA*P; Bx, bz, pb, rd, vc; NY (DeCandido 2001); Q, a, ba, fa, fm, i, j, ks, u, wl; K(DeCandido 2001); R, ca, fk, go, gr, sb, w, wp; -     Lythrum salicaria is a perennial herb, 0.5-2.7 m tall, densely colonial with as many as 30-50 stems arising from a mature woody root crown. No mycorrhizae have been found associated with the roots (Mal et al. 1992); stems erect, branches opposite, each pair at right angle to next up stem, candelabra-like, stems 4-sided, usually […]
Macleaya cordata  (Bacconia c.) plume poppy Papaveraceae MACO; Bx, pb (DeCandido 2001); R, fc; -    Macleaya cordata is a perennial herb to 2.5 m tall, aggressively colonial from fleshy rhizomes, stems stout, waxy-pale, sap yellow-orange.  Leaves alternate, stalks long, blade to ca 20 cm long, 24 cm wide, palmately veined, densely wooly white below, dark green above, deeply round-lobed and toothed.  Flowers greenish-white, small, no petals; petals replaced by numerous stamens; […]
Maianthemum canadense Canada mayflower Liliaceae MACA; Bx, bg, br, pb, vc; NY iw; Q a, cu; R, ah, an, ar, bd, bk, cb, cn, d, ev, gb, gr, h, js, k, lp, lt, mc, pm, r, ro, sm, v, t, w, wp, wt; -     Maianthemum canadense is a perennial monocotyledon; a summer-green herb, 4-15 cm tall; colonial ground cover from slender white rhizomes; often forming carpets; roots associated with vesicular-arbuscular endomycorrhizal fungi (Berliner and Torrey 1989); winter plants with next season’s preformed bud in a small white shoot at the base of old stems (Levine 1995).  Leaves alternate, stem […]
Maianthemum racemosum  (Smilacina racemosa) feathery false lily of the valley; false solomon’s seal Liliaceae SMRA; Bx, bg, br, bz, cf, pb, sf, up, vc; NY, hb, iw; Q, a, cu, f; K p; R, ah, ar, bd, c, cl, cs, d, gb, h, k, lp, lt, pm, ro, sv, w, wp, wt;  -   Maianthemum racemosum is a perennial,                monocotyledon, summer-green, herb; stem 40-80 cm long (usually closer to 40) curved, stem green; sparingly clonal from short, thick rhizomes to 1 cm diameter, each becoming independent, new roots produced in summer from rhizome of previous year, may live up to 5 years; […]
Maianthemum stellatum  (Smilacina stellata) starry false lily of the valley; starflower Liliaceae SMST; Q; K; R, pm; -   Maianthemum stellatum is a perennial,   monocotyledon, summer green herb to 60 cm tall (usually less), stem unbranched, colonial from a creeping rhizome.  Leaves alternate, ranked along stem, to 15 cm long, 5 cm wide, tip taped to point, finely hairy below; stalkless, usually folded, somewhat clasping, lance-shaped, veins parallel to midrib  Flowers white to 1 […]
Malva moschata musk-mallow Malvaceae MAMO*; Bx, pb (DeCandido 2001); -    Malva moschata is a perennial herb 0.4-1 m tall, from a taproot, stems erect, rough-hairy, stipules present.  Leaves alternate, stalk 2-7 cm long, blade 3-6 cm long, round, deeply 5-7 pinnately parted, lobes often lobed again, margin toothed, notched; Overwinters as a rosette of rounded, entire leaves with toothed margins.  Flowers pink, white, to pale purple; […]
Malva neglecta common mallow; cheeses Malvaceae MANE*; Bx, nb, pb; NY, bl (Stalter and Tang 2002), hb, mn; Q, j, lk; K, p; R, c, hs; -     Malva neglecta is an annual or biennial herb, from a taproot, prostrate or reclining, to 1 m long, branched from base, stems densely hairy; Seedling leaves heart-shaped, 0.5-0.7 cm long, 0.3-0.4 cm wide (Hagood 2007); stipules 0.5 cm long, 0.3 cm wide.  Leaves alternate, stalks 5-20 cm long, blade 2-6 cm long and wide, kidney-shaped […]
Matricaria matricarioides  (M. discoidea) pineapple-weed Asteraceae MAMA*; Bx, br, pb, sf, sn, vc; NY, bl (Stalter and Tang 2002); Q, f, i, j; K, fs; R, mm, sm; -     Matricaria matricarioides is an annual herb, 5-40 cm tall, mostly about 15 cm, pineapple-aromatic scented, freely branched, leafy, from a taproot.  Leaves alternate, mostly stalkless, blade 1-3 times pinnate, 1-6 cm long, 0.5-2 cm wide, finely 1-3 times pinnately dissected, fern-like, ultimate segments finely linear.  Flowers in heads, yellow, corollas 4-toothed, 0.1 cm long, all disks […]
Matricaria recutita  (M. chamomilla) German chamomile Asteraceae MARE*; Q (DeCandido 2001); R (DeCandido 2001); -    Matricaria recutita is an annual herb, 20-80 cm tall, pineapple-aromatic scented, branching. Leaves alternate, twice pinnately divided, segments filament-like.  Flowers in heads about 2 cm wide, ray flowers white, 10-20, 0.4-1 cm long, disk 0.6-1 cm wide, flowers yellow; basal bracts membranous-margined, floral base (receptacle) cone-shaped, hollow, surface smooth (no scales); blooms and fruits May-Oct.  Fruit dry, […]
Mazus pumilus  (M. japonicus) Japanese mazus Scrophulariaceae MAPU*; Bx, p (DeCandido 2001); Q, fh (M. Feder p.c.); j (Stalter and Lamont 2002); -    Mazus pumilus is an annual herb, lax, to 15 cm hairy, often with several stems.  Leaves opposite, mostly in basal rosette, blade spatula-shaped 1-4 cm long,0.5-1.5 cm wide, often purplish below, margin with a few coarse teeth, stem leaves alternate, smaller.  Flowers blue-violet with yellow and white markings, to 1 cm long, bilaterally symmetrical, tubular, 2-lipped, […]
Medeola virginiana Indian cucumber root Liliaceae MEVI; Q, a; R, ev, h, t, w -     Medeola virginiana is a perennial monocotyledon herb to about 50 cm tall, colonial from a thick white, horizontal, succulent tuber 3-8 cm long, stem 30-70 cm, slender, young stem usually wooly-hairy, persisting at leaf bases.  Leaves in two whorls, the lower one with 5-11 leaves 6-12 cm long, 2-5 cm wide, lance-shaped, widest above middle, […]
Medicago lupulina black medick Fabaceae MELU*; Bx, cm, pb, sn, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct; Q, cu, f, j, rw, tl; K, fl, p; R, c, js, jl, k, mm, wp; -     Medicago lupulina is an annual or biennial herb, taprooted with thin secondary roots forming a dense mat; roots form nodules containing nitrogen-fixing Rhizobium bacteria; stems erect, 4-angled, prostrate or reclining, 10-80 cm long; stipules lanceolate, 0.5-1.5 cm long, 0.5 cm wide (Radford et al. 1968; Yatskievych 2006).  Leaves alternate, 3-parted, leaflets 1-2 cm long, 0.3-1 cm wide, […]
Medicago sativa alfalfa; lucerne; medic Fabaceae MESA*; Bx, pb (DeCandido 2001); Q, a, j; R, jw, v; -      Medicago sativa is a perennial herb, deep-rooted, tufted, deep-rooted; roots form nodules containing nitrogen-fixing Rhizobium bacteria; stems slender, 0.3-1 m tall, stipules lance-shaped, 0.5-2 cm long, mostly entire (Radford et al. 1968).  Leaves alternate, 3-parted, terminal leaflet stalked, leaflets 1-3 cm long, 0.3-0.8 cm wide, widest above the middle, toothed at top, dark, dull green, leaf […]
Melilotus alba sweet white clover Fabaceae MEAL*; Bx, cm, g, pb, sn, vc; Q, a, fr, ft, i, j, rw, tl, wl; K, do, fs, pl; R, bm, c, d, cs, fk, hs, jl, js, lp, mls, mm, sm, sv, ty, v, wp, wt; -     Melilotus alba is an annual or biennial herb, 0.3-1.2 m tall, from a taproot, root nodules associated with nitrogen-fixing Rhizobium bacteria, contractile roots pull root crown below soil in winter; stems 1-10 from root crown, erect, grooved, usually hairy near top; stipules linear, 0.4-1 cm long, 0.1 cm wide.  Leaves alternate, 3-parted, stalk ca 1 cm long, […]
Melilotus officinalis sweet yellow clover Fabaceae MEOF*; Bx, cm, pb, sn; NY (DeCandido 2001); Q, j, vb, tl; K, fs; R, js, lp, mm, v; -     Melilotus officinalis is a biennial herb, 0.4-2 m tall, from a taproot, root nodules associated with nitrogen –fixing Rhizobium bacteria, stems erect or ascending; stipules lance-shaped 0.5-0.8 cm long (Radford et al. 1968).  Leaves alternate, 3-parted (trifoliate), leaflets 1-2.5 cm long, 0.5-2 cm wide (Yatskievych 2006), obovate to oblanceolate (inversely oval or lance-shaped), mature leaflets mostly hairless, […]
Mentha arvensis field mint Lamiaceae MEAR; R (DeCandido 2001); -   Mentha arvensis is a perennial herb, 20-80 cm tall, colonial from rhizomes; stems 4-sided sharply angled, hollow, upper parts hairy, crushed plant mint scented. Winter plant with sharply 4-sided stem, opposite branches, calyxes tubular, radially symmetrical, sharply 4-lobed (Levine 1995). Leaves opposite, short-stalked, blade 2-8 cm long, 0.6-4 cm wide (Yatskievych 2006), rhombic-elliptic, tip long-pointed, base […]
Mentha Genus mint Lamiaceae -    Mentha is a genus of perennial herbs (ours), colonial from rhizomes, aromatic, most with “minty” aroma; stems 4-sided.  Leaves opposite, simple, most with puckered by impressed veins; margins toothed.  Flowers white to blue or lavender, small, tubular, 4-parted and nearly radially symmetrical by fusion of 2 upper lobes, this lobe wider and usually notched at tip; […]
Mentha spicata spearmint Lamiaceae MESP*; NY, hb, rr; Q (DeCandido 2001); R, lp, v; -   Mentha spicata is a perennial herb from rhizomes, stems 0.3-1 m tall, square, mostly hairless, strong minty odor, often reddish towards base; larger plants usually branched below inflorescence.  Leaves opposite, stalk 0-0.3 cm long, blade 3-7 cm long, 1-2.5 cm wide, narrowly egg-shaped to lance-shaped, surface puckered by deeply impressed veins, tip pointed, base rounded, […]
Mentha suaveolens apple-mint Lamiaceae MESU*; Q, f; -   Mentha suaveolens is a perennial herb colonial from rhizomes, stems stout, 0.4-1 m tall, 4-sided, usually hairy, plant strongly, sweet-aromatic.  Leaves opposite, stalk little to none, blade 2-5 cm long, 1-4 cm wide, densely, softly, whitish hairy, tip rounded to barely pointed, base usually lobed, sometimes clasping, margin coarsely toothed.  Flowers bluish-white, tubular, ca 0.3 cm […]
Mentha x piperita peppermint Lamiaceae MEXP; Q, j (Stalter and Lamont 2002); R, lp; -    Mentha x piperita is a perennial herb, 0.6-1 m tall, strongly minty, sterile hybrid of M. aquatica and M. spicata, aggressively colonial from rhizomes and often also stolons, stems square, slender.  Leaves opposite, stalk 0.4-1.5 cm long, blade 3-6 cm long, 1.5-3 cm wide, egg-shaped, tip pointed, sometimes blunt, base blunt, margin toothed.  Flowers purplish to pinkish, to 0.5 cm long, […]
Micranthes virginiensis (Saxifraga v.) early saxifrage Saxifragaceae SAVI; R, gb (E. Danielsen 2016); -   Micranthes virginiensis is a perennial herb from a thick rhizome, flowering stems to 40 cm tall, glandular-hairy.  Leaves in a basal rosette, egg-shaped to 5 cm long, tip blunt, base narrowed to leaf stalk, often purple below, margin toothed to entire.  Flowers white, regular, 5-parted, petals to 0.6 cm long, spatula-shaped, along branches of upper stem; […]
Mimulus alatus winged monkey flower Scrophulariaceae MIAL; Bx, pb (DeCandido 2001); R (DeCandido 2001); -   Mimulus alatus is a perennial herb from rhizomes, stems 0.2-1.3 m tall, 4-sided, hollow, winged at corners.  Leaves opposite, each pair at right angles to the next (decussate), stalk 1-2 cm, winged, blade 6-13 cm long, 3-5 cm wide, reduced upwards, lance-shaped, pointed at both ends, margin sharply toothed.  Flowers violet to pale lavender, yellow in […]
Mimulus ringens monkey flower Scrophulariaceae MIRI; Bx, pb (DeCandido 2001); R ah, gr, js -   Mimulus ringens is a perennial herb, 20-130 cm tall, (much like M. alatus but leaves stalkless, stems scarcely winged); colonial from rhizomes, stems hollow, sharply 4-sided, angles narrowly winged.  Leaves opposite, decussate, stalkless (sessile), blade 6-13 cm long, 2-3 cm wide, lance-shaped, progressively reduced above, tip pointed, base often clasping stem, margin toothed.  Flowers blue-violet, yellow in throat, hairy, […]
Minuartia caroliniana  (Arenaria c.; Sabulina c.; Sabulina c.) pine-barren stitchwort Caryophyllaceae ARCA; Q (DeCandido 2001); R (DeCandido 2001); -     Minuartia caroliniana is a perennial herb flowering stems to 20 cm tall. Basal stems often matted, prostrate, from a taproot and woody root crown, ascending stems stiff, densely leafy below, glandular-hairy, slightly rough.  Leaves opposite, linear, rigid to 1 cm long, triangular in cross-section; flowering stalks to 6 cm, very slender, almost leafless, erect or […]
Mirabilis hirsuta  (Oxybaphus hirsutus; Allionia hirsuta) hairy umbrella-wort Nyctaginaceae MIHI(*);Q (DeCandido 2001); - Mirabilis hirsuta is a perennial herb to 1 m tall, stems hairy, especially around nodes.  Leaves opposite, often stalkless, blade 1-2 cm wide, lance-shaped.  Flowers pink, petals none, calyx flower-like, tubular, 1 cm long, 5 lobes, tube wrapped tightly around ovary, flaring above in a cup-like, 5-lobed bract ca 0.5 cm wide, glandular-hairy, becoming 1-2 cm wide, […]
Mirabilis nyctaginea heart-leaved umbrella-wort; four o’clock Nyctaginaceae MINY(*); Bx, pb (DeCandido 2001); Q, a, j; K, pl; R (DeCandido 2001); - Mirabilis nyctaginea is a perennial herb from a large taproot to 7 cm wide, stems coarse, to 1.5 m tall, smooth, gray-green, nodes swollen, stem repeatedly forked. Leaves opposite, stalks 1-3 cm long, blade to 3-10 cm long,to 7 cm wide (Yatskievych 2006), egg to heart-shaped, tip pointed, base lobed or truncate (similar to those of […]
Mitchella repens partridgeberry Rubiaceae MIRE; Bx, pb (DeCandido 2001), vc (Wang 2016); Q, j (Stalter and Lamont 2002); R, ar, gb, h, pc, t, wp; -    Mitchella repens is a perennial herb, stems 10-30 cm long, trailing, small, evergreen, mat-forming colonial, rooting at nodes; roots associated with ericoid mycorrhizal fungi (Berliner and Torrey 1989); most reproduction is vegetative; life span at least 15 years (Bierzychudek 1982).  Leaves opposite, stalks present, blade 1-2 cm long and wide, almost round, dark green, leathery, […]
Moehringia lateriflora (Arenaria l.) bluntleaf sandwort; grove sandwort Caryophyllaceae ARLA; R (DeCandido 2001); -    Moehringia lateriflora  is a perennial herb; colonial from widely creeping, thread-like rhizomes, stems to 40 cm long, very fine, with backward-pointing hairs.  Leaves opposite, narrowly elliptic, to 5 cm long, 0.8 cm wide, hairy, sprinkled with tiny translucent dots, tip blunt to pointed.  Flowers white, petals 5, to 0.6 cm long, sepals to 0.3 cm; inflorescence […]
Mollugo verticillata carpet-weed Molluginaceae MOVE*; Bx, pb (DeCandido 2001); NY, bl (Stalter and Tang 2002), ct, mn; Q, j, rb; K, fs; R, bm, c; -   Mollugo verticillata is an annual C4 herb (Ludwig et al. 2010), from a taproot, prostrate, stem repeatedly forked, forming mats to 40 cm wide.  Leaves in whorls of 3-8, stalk short, blade 1-3 cm long, to about 0.4 cm wide, narrow, widest above middle (oblanceolate), tapering to base, midrib depressed, conspicuous.  Flowers white to pale green, 0.4-0.5 […]
Monotropa uniflora Indian pipe Monotropaceae MOUN; Bx, pb, vc; NY, hb; Q, a, cu, j (Stalter and Lamont 2002); R, ah, bd, js, mc, ro, sv, w; -   Monotropa uniflora is a perennial herb, from a ball of fibrous roots; roots associated with very specialized monotropoid mycorrhizas (Basidiomycetes, family Russulaceae), (Smith and Read 1997), that may absorb sugars from nearby, photosynthetic plants (Allen 1991; Berliner and Torrey 1989), stems 10-20 cm tall, white, often becoming pink with age, often in clumps, waxy-white […]
Muscari botryoides grape hyacinth Liliaceae MUBO*; Bx, pb (DeCandido 2001); NY (DeCandido 2001); K, p; R (DeCandido 2001); - Muscari botryoides is a perennial monocotyledon herb from bulbs; spring ephemeral; somewhat colonial from bulb offsets; flowering stems leafless.  Leaves all basal, to 25 cm long, 0.3-0.8 cm wide, linear, grooved, U-shaped in cross section (Yatskievych 2006). Leaves often emerging in late summer or autumn, overwintering, disappearing in late spring after flowering. Flowers blue, fragrant, radially symmetrical, […]
Myosotis Genus forget-me-not Boraginaceae - Myosotis is a genus of herbs, often hairy, rough-textured; no stipules.  Leaves alternate, simple, entire.  Flowers blue, occasionally white, 5-parted, radially symmetrical, petals fused, tube short, petal lobes spreading, tips rounded, overlapping; stamens 5, arising from petal tube, alternating with and shorter than petal lobes; ovary superior, 4-lobed; style attached to the floral base, (gynobase, a prolonged […]
Myosotis laxa small forget-me-not Boraginaceae MYLA; Bx, pb (DeCandido 2001), vc; Q (DeCandido 2001); R (DeCandido 2001); - Myosotis laxa is an annual to short-lived perennial herb, 10-40 cm tall or long, stems slender, often bent near base, rooting at nodes.  Leaves alternate,1.5-9 cm long, to 2 cm wide, the lower ones spatula-shaped, upper leaves elliptic to lance-shaped. Flowers blue with yellow eye, tubular, 0.2-0.5 cm wide across top, calyx hairy 0.3-0.5 cm, lobes as […]
Myosotis micrantha  (M.stricta; M. arvensis) forget-me-not; blue scorpion grass Boraginaceae MYMI*; Q, j (Stalter and Lamont 2002); - Myosotis micrantha is an annual or winter annual herb to 20 cm tall, stems hairy, often branched from base.  Leaves alternate 2 cm long, 0.7 cm wide, lower leaves narrow, widest above middle, upper oblong to lance-shaped.  Flowers blue with yellow eye (occasionally white), 0.1-0.2 cm wide, tubular, petal lobes spreading but not flat; calyx 0.3-0.5 cm […]
Myosotis scorpioides true forget-me-not Boraginaceae MYSC*; R (DeCandido 2001); - Myosotis scorpioides is a perennial herb to 60 cm tall, roots fibrous, stem angled, often creeping at base, producing long creeping stems (stolons), finely hairy.  Leaves alternate, 2.5-8 cm long, 0.7-2 cm wide, the lower ones widest above middle (oblanceolate), upper leaves elliptic to lance-shaped.  Flowers blue with a yellow eye, tubular, petal lobes spreading, 0.5-1 cm […]
Myosotis verna early scorpion-grass; spring forget-me-not Boraginaceae MYVE; Bx, pb (DeCandido 2001); -   Myosotis verna is an annual or winter annual herb, 5-40 cm tall, stiffly erect, most parts bristly-hairy.  Leaves alternate, 1-5 cm long, 0.2-1 cm wide, lowest leaves narrow, widest above middle, stalked, becoming oblong, stalkless above.  Flowers white, 0.1-0.2 cm wide across top, not flat; calyx 0.4-0.7 cm in fruit, stiffly hairy, bilaterally symmetrical, three lobes […]
Myriophyllum humile low water-milfoil Haloragaceae MYHU; R (DeCandido 2001); -   Myriophyllum humile is a submersed to emersed perennial aquatic herb to 1 m long, stem tip often above water surface when flowering; underwater stems lax.  Leaves alternate, sub-opposite, irregularly scattered, sometimes whorled; pinnate, very finely divided, to 3.7 cm long, leaflets thread-like; stems emerging above surface or on mud, with leaves alternate, linear, undivided, or […]
Myriophyllum spicatum European water-milfoil Haloragaceae MYSP*p; Q, gp; -   Myriophyllum spicatum is a perennial submerged aquatic herb, from root crowns, inflorescences emergent, stems, to 7 m long (usually no more than 50 cm longer than water depth) but often in fragments floating along water surface that form roots and sink to the bottom, freely branching at water surface, forming a dense canopy, stems […]
Najas minor eutrophic water-nymph Najadaceae NAMI*; NY, ct; - Najas minor is an annual submerged, rooted aquatic herb, stems 10-20 cm long, very slender, to 0.1 cm thick.  Leaves opposite, 0.5-3.5 cm long, to 0.02 cm wide, needle-thin, margins minutely toothed, base expanded into a short sheath, margin fringed (use lens).  Flowers very small, inconspicuous solitary in axil, unisexual (monoecious); male flowers with solitary anther; female […]
Narcissus pseudonarcissus daffodil Liliaceae NASP*; Bx, br, pb; NY (DeCandido 2001); Q, j (Stalter and Lamont 2002); K, p; R, ah, gb, gr, ok, sm; -   Narcissus pseudonarcissus is a perennial monocotyledon spring ephemeral herb, from bulbs, sparsely colonial from bulb offsets, flowering stems hollow, 20-40 cm long, juicy, sap mucilaginous.  Leaves, alternate, all basal, to 20-40 cm long, linear, dull blue-green, rather thick, dying back in summer.  Flowers yellow, radially symmetrical, 4-6 cm wide, tubular at base, corolla 6-parted with […]
Nepeta cataria catnip Lamiaceae Bx, nb, pb; Q (DeCandido 2001); R, hs; -   Nepeta cataria is a perennial herb to 1 m tall from a taproot, stem branched above, crushed leaves aromatic but not strongly “minty”, most parts densely softly gray-hairy.  Leaves opposite, to 8 cm long, egg to heart-shaped, tip pointed, base blunt to lobed, margin coarsely toothed, white-hairy below, stalk half as long as blade.  Flowers whitish […]
Nuphar lutea ssp. advena (Nuphar advena) southern pond lily; spatterdock, cowlily Nymphaeaceae NUAD; Bx, pb, vc; Q, a; R, cp, e, h; -   Nuphar lutea ssp. advena is a perennial, rooted aquatic herb; colonial from thick leaf-bearing rhizomes 5-10 cm thick (Flora of North America Editorial Committee, eds.  1993+), rooted in mud. Leaves emergent, rarely floating or submerged, alternate, leaf stalk oval or round in cross section, interior with numerous small air cavities, blade broad, 12-40 cm […]
Nuphar lutea ssp. variegata (Nuphar variegata) spatterdock; variegated yellow pond lily Nymphaeaceae NUVA; R, cp; -   Nuphar lutea ssp. variegata is a perennial, aquatic herb; colonial from rhizomes 2.5-7 cm thick (Flora of North America 1993+).  Leaves alternate, usually floating, stalks flattened, winged, blade 7-35 cm long, 5-25 cm wide, base deeply lobed, lobes often overlapping.  Flowers yellow, 2.5-5 cm wide, sepals 6, thick, broad, deep yellow to green outside, often purplish […]
Nuphar lutea subsp. pumila (Nuphar microphylla) yellow pond lily Nymphaeaceae R (DeCandido 2001); - Perennial herb, rooted aquatic, colonial from leaf-bearing rhizomes to 2 cm thick, slender.  Leaves alternate leaf stalks very thin, flattened above, blades both floating and submerged, floating leaves 5-10 cm long, elliptic, tip rounded, base lobed, lobes with narrow “V” shaped sinus at least half the length of the blade; submerged leaves kidney-shaped, filmy.  Flowers yellow inside […]
Nuttallanthus canadensis  ( Linaria c.) blue toadflax Scrophulariaceae LICA2; Bx, cm (seed mix); NY (DeCandido 2001); Q, a, i, fr, j, tl; K, m, p; R, e, h, lp, ro, sm, sv; -     Nuttallanthus canadensis is an annual, or winter annual herb, 10-50 cm tall, from a taproot; flowering stems erect, very slender, plant with winter basal rosette of several slender, leafy, reclining, nonflowering, shoots to 10 cm long.  Leaves of flowering stem alternate, linear, 1-3.5 cm long, 1-2.5 cm wide, widely separated along stem, leaves of basal […]
Nymphaea odorata water-lily Nymphaeaceae NYOD; Bx, pb (DeCandido 2001); Q a, cr; R, bd, h;  -   Nymphaea odorata is a perennial,  floating-leaved aquatic herb; colonial from a rhizome rooted in mud.  Leaves alternate, leaf stalks with 4 large air-filled passages; blade floating, almost circular, 10-30 cm diameter, often purple or red below, base sharply lobed, sinus narrow, with straight sides.  Flowers white, fragrant, 7-20 cm wide; petals 17-25, 3-10 cm long, narrowly […]
Nymphoides peltata yellow floating heart Menyanthaceae NYPE*; Q, a, f; K, p; - Nymphoides peltata is a perennial, floating-leaved, rooted aquatic herb, colonial from rhizomes, stems stout, to 0.3 cm thick.  Leaves opposite, pair-members unequal in size, 5-15 cm long and wide, rounded, tip blunt, base slightly lobed, margin wavy-toothed.  Flowers yellow, to 2.5 cm wide petal lobes slightly fringed below, in small clusters, June-Sept.  Fruit capsule to 2.5 cm, beaked, […]
Oclemena nemoralis  (Aster nemoralis) bog aster Asteraceae ASNE; R (DeCandido 2001); -     Oclemena nemoralis is a perennial herb, 10-60 cm tall, slightly sticky, rough-hairy, colonial from rhizomes, stems solitary from rhizome and stolon tips.  Leaves alternate, linear to lance-shaped, 1-5 cm long, 0.2-1 cm wide, stalkless, mostly uniform, numerous along stem 40-75 below inflorescence.  Flowers: ray flowers 13-27, pink to purplish, 0.9-1.5 cm long, base of flower […]
Oenothera biennis evening primrose Onagraceae OEBI; Bx, br, bz, pb, sf, sn, vc, wv (Yost et al. 1991); NY, ct, hb, iw, wr; Q, a, dp, fa, fr, ft, i, j, rb, rw, tl, wl; K, do, fs, m, p, pl; R, ar, c, cg, cs, d, e, fk, gb, gr, h, hs, jl, mls, ok, pr, ro, sm, sv, t, ty; -    Oenothera biennis is a biennial, winter annual, or briefly perennial herb, from a thick, fleshy taproot; no mycorrhizal associations reported (Hall et al. 1988); flowering stem 0.5-2 m tall, leafy, often reddish, hollow, larger plants branched above.  Leaves alternate, 1st year rosette leaves long, narrowly egg-shaped, pointed at both ends, tinged with red spots, midrib […]
Oenothera fruticosa sundrops Onagraceae OEFR; R (DeCandido 2001); -   Oenothera fruticosa is a perennial herb to 1 m tall, stems slender, appressed-hairy, colonial from rhizomes.  Leaves alternate, stalk 0-1 cm long, blade to 11 cm long, 2.5 cm wide, elliptic; leaves of first year rosette egg-shaped.  Flowers clear, bright yellow, showy, to 5 cm wide, 4 petals, 1.5-2.5 cm long, notched at top, folding up […]
Oenothera Genus evening primrose Onagraceae - Oenothera is a genus of New World herbs, mostly in the U.S.A. Leaves alternate, usually narrow, simple.  Flowers yellow (ours), mostly open only one night, 4-parted, radially symmetrical, sepals, petals and stamens arising from top rim of calyx tube (hypanthium); petals 4, free; sepals fused in bud, splitting as flower opens and becoming curled back (reflexed); stamens […]
Oenothera laciniata cut-leaved evening-primrose Onagraceae OELA; Bx, pb (DeCandido 2001); K, fl (Z. Wang 5/2016), m (M. Feller personal communication);  -   Oenothera laciniata is an annual herb, to 40 cm tall.  Leaves alternate, to 8 cm long, narrow, margin wavy-toothed, to pinnately divided, green, sparsely hairy, tapered to base.  Flowers yellow, petals to 1.8 cm long, May-Oct.  Fruit a linear capsule to 3.5 cm long.  Wetland status: FACU-.  Frequency in NYC: Very infrequent (NYS rare, S1, E).  Origin: […]
Oenothera parviflora small-flowered evening primrose Onagraceae OEPA; Bx, pb (DeCandido 2001); Q, j (Stalter and Lamont 2002); -   Oenothera parviflora is a biennial or brief perennial herb, 10-80 cm tall, very similar to O. biennis but stem rarely branches. Hairier than O. biennis, hairs having enlarged, swollen reddish bases. Leaves alternate, stem leaves narrowly lance-shaped, somewhat fleshy and thickened. Upper leaves becoming leafy floral bracts, the lower flowers shorter than the bracts. Flowers yellow, petals 4, 1-2 cm […]
Oenothera perennis small sundrops Onagraceae OEPE; Bx, pb (DeCandido 2001); R (DeCandido 2001); -   Oenothera perennis is a perennial herb, roots fibrous; stems 20-60 cm tall, usually unbranched.  Leaves alternate, stalk to 0.7 cm long; blade 3-6 cm long, to 0.8 cm wide narrow, elliptic to widest above middle, tip blunt, base tapered to stalk, leafy bracts of inflorescence smaller. Flowers yellow, petals 0.5-1 cm long, heart-shaped, notched at tip; […]
Oldenlandia uniflora (Hedyotis u.) clustered mille graines Rubiaceae HEUN; R (DeCandido 2001); -    Oldenlandia uniflora is an annual herb, stems 10-50 cm long, erect to spreading, usually hairy, sparsely branched.  Leaves opposite, stalkless, lance-shaped, 1-2.5 cm long, margins white-hairy.  Flowers white, radially symmetrical, tubular, 0.2 cm wide, petal lobes 4, shorted than sepals; inflorescence of dense clusters, all flowers with same style length (homostylous); blooms and fruits July-Oct.  Fruit dry, […]
Oligoneuron rigidum var. rigidum (Solidago rigida) stiff goldenrod Asteraceae SORI; K, m (possibly planted; Lamont and Yong 2002); Q, j (M. Feder p.c.);  - Oligoneuron rigidum var. rigidum is a perennial herb 25-150 cm tall, usually hairy.  Leaves alternate, stalk (petiole) of basal leaves to over 25 cm long, blade 6-25 cm long, 2-10 cm wide, mostly basal, elliptic, tip rounded to basely pointed, middle and upper leaves stalkless, smaller.  Flowers yellow, of two types in small heads, rays 7-14, to […]
Opuntia humifusa Eastern prickly pear cactus Cactaceae OPHU; Bx, pb (DeCandido 2001); NY, tr; Q, j (Stalter and Lamont 2002); K (DeCandido 2001), fl (Zihao Wang 2016); R, sm (planted);  -   Opuntia humifusa is a perennial herb from fibrous roots, forming mats, stems segmented, photosynthetic, formed of thick, fleshy, flat oval pads 4-12 cm long, 2-8 cm wide with small bristly-spiny cushions scattered over the surface, gray-green turning reddish in winter.  Leaves none.  Flowers yellow, showy, 4-8 cm wide, numerous petals, sepals greenish, grading into petal; stamens […]
Ornithogalum umbellatum star of Bethlehem Liliaceae ORUM*p; Bx, br, pb, rd, vc; NY, bl (Stalter and Tang 2002), ct, hb, iw; Q, cu, j; K, p; R, cg; -   Ornithogalum umbellatum is a spring ephemeral, perennial monocotyledon herb, to 30 cm tall, from a bulb; poisonous (Kingsbury 12964), colonial from bulb offsets.  Leaves basal, linear, 20 cm long or more, 0.5-0.6 cm wide, somewhat fleshy, shiny, green with white central stripe along midrib above, leaves appear March-April, often die back before flowers appear, plant […]
Orobanche uniflora cancer-root Orobanchaceae ORUN; Bx, pb (DeCandido 2001); Q (DeCandido 2001); R (DeCandido 2001); -    Orobanche uniflora is an annual her; a root parasite on many kinds of plants, plant without chlorophyll, main stem mostly underground, 1-3 cm long.  Leaves alternate, few, reduced to whitish scales, 0.2-0.3 cm long.  Flower white to violet with 2 yellow stripes inside, fragrant, 2 cm long, tubular, bilaterally symmetrical, curved downward, glandular-hairy outside, petal lobes […]
Osmorhiza claytonii sweet cicely Apiaceae OSCL; Bx, vc; NY, mn; Q, a, cu; -   Osmorhiza claytonii is a perennial herb to 1m tall from thick roots, aerial parts without odor, stem hairy.  Leaves alternate, few, the upper stalkless (sessile), the lower stalked, base wide, clasping stem; blade 2-3 times compound, 10-30 cm long, hairy, leaflets 1.5-9 cm long, 1-4 cm wide, egg-shaped, margins blunt-toothed to lobed, winter rosette leaves […]
Osmorhiza longistylis anise root Apiaceae OSLO; Bx pb (DeCandido 2001), wv (Yost et al. 1991); Q, cu, f; R (DeCandido 2001); -   Osmorhiza longistylis is a perennial herb to 1.2 m tall, plant anise-scented, from thick, carrot-like, aromatic roots to 1 cm thick, stem smooth, to finely hairy, sometimes purple.  Leaves alternate, few, the upper stalkless (sessile), the lower stalked, base wide, clasping stem; blade 2-3 times compound, 10-30 cm long, hairy, leaflets 2-10 cm long, 1-5 […]
Oxalis corniculata creeping wood-sorrel Oxalidaceae OXCO*; NY, hb, rr; Q (DeCandido 2001); -   Oxalis corniculata is a perennial herb, to 20 cm tall (usually less), from a taproot, plant usually purple or purple-tinged, stems in tufts, colonial from creeping stems, horizontal stolons, rooting at nodes, branching; hairs not septate (use lens).  Leaves alternate, leaf stalk with swollen joint near base, (stipulate; use lens); blade 3-parted, leaflets 1-2 cm […]
Oxalis dillenii  (O. filipes) slender yellow wood sorrel Oxalidaceae OXDI; NY, bl (Stalter and Tang 2002); Q, j (Stalter and Lamont 2002); R (DeCandido 2001); -   Oxalis dillenii is a perennial herb 10-40 cm tall, very similar to O. corniculata but not purple tinged, no stolons, taprooted, stems often clustered, erect, eventually kneeling (decumbent); densely fine-hairy, hairs pointed, not septate; stipules to 0.3 cm long, often much smaller.  Leaves alternate, 3-parted, leaflets 1-2 cm wide, heart-shaped, notched at tip, bright green, somewhat succulent, sour […]
Oxalis stricta common yellow oxalis Oxalidaceae OXST; Bx, br, pb, sd, sf, up, vc, wv (Yost et al. 1991); NY (DeCandido 2001); Q, a, cu, ft, j; K, p; R, al, bm, cl, js, sv, w; -   Oxalis stricta is a perennial herb to 50 cm tall, colonial from long thin, pale, succulent, rhizomes, branching and sending up new shoots, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); stem usually erect, hairy, some hairs septate, base of stem often reddish; no stipules.  Leaves alternate, 3-parted, leaflets heart-shaped, notched at tip, bright […]
Pachysandra terminalis pachysandra Buxaceae PATE*p; Bx, pb, vc, wv (Yost et al. 1991); Q, a; R, c, is, r; -   Pachysandra terminalis is a perennial herb, stems 10-40 cm long; evergreen ground cover, rooting at nodes, root sprouts, extensively clonal.  Leaves alternate, 3-8 cm long, egg-shaped, with few, rounded teeth near tip, widest above middle, narrowed to base, spiraled at top of stem; leaves appear to last a little over one year, the spiral from […]
Packera aurea  (Senecio aureus) golden ragwort Asteraceae SEAU; Q; -   Packera aurea is a perennial herb 30-80 cm tall, colonial from leafy stolons or rhizomes 3-15 cm long.  Leaves alternate, basal leaves long-stalked, blade mostly broadly heart-shaped, to 11 cm long and wide, tips rounded, margin blunt-toothed, often dark purplish on underside, stem leaves much reduced, pinnately divided, upper leaves stalkless.  Flowers yellow, 0.6-ray flowers 1.3 […]
Panax trifolius dwarf ginseng Araliaceae PATR; Bx, bg, vc; R (R. DeCandido 2001), SSI (Z. Wang 2016); -   Panax trifolius is a perennial, spring ephemeral, small herb from a round, round, tuberous root, stem 5-20 cm tall, unbranched.  Leaves in one whorl, palmately compound, 3-5 parted, leaflets 4-8 cm long, to 2 cm wide, tip blunt, base unequal, margin finely toothed. Flowers white, 5-parted, tiny, petals 0.1 cm long, no sepals none; ovary inferior, […]
Parietaria pensylvanica pellitory Urticaceae PAPE; NY, ct; -   Parietaria pensylvanica is an annual herb, finely hairy, 10-40 cm tall, stem somewhat translucent, pale green.  Leaves alternate, stalk thin, often pinkish, translucent; blade lance-shaped 3-8 cm long, tip tapered to rounded tip, base wedge-shaped, 3-veined from above base, margin entire.  Flowers green, tiny, amid linear bracts about 0.5 cm long, in mid to upper leaf […]
Paronychia canadensis forked chickweed Caryophyllaceae PACA; Bx, pb (DeCandido 2001); R (DeCandido 2001); -   Paronychia canadensis is an annual herb from a taproot, 3-40 cm tall, stems erect, very slender, hairless, forked many times, bushy-branched, internodes elongate; stipules membranous, needle-shaped, to 0.4 cm long.  Leaves opposite, elliptic, thin, 0.3-3 cm long, 0.1-1 cm wide.  Flowers pale green to brownish, 0.1 cm long, cylindric, above small membranous bracts, (use lens) no […]
Paronychia fastigiata hairy forked whitlow-wort Caryophyllaceae PAFA; R, ot; - Paronychia fastigiata is an annual herb from a taproot, stem erect, 4-30 cm tall, slender, finely hairy, branched well above base in an open, forked (dichotomous) pattern, nodes slightly swollen, stems often red with age; stipules to 0.4 cm long, membranous, needle-shaped, margins sometimes fringed.  Leaves of major branches opposite, stalkless, blade narrow, 0.2-2.5 cm long, […]
Pastinaca sativa wild parsnip Apiaceae PASA*; Bx, cm, ht, pb; NY, wr; Q, a, j, u; K, fl; R, c, cg, fk, h, js, lp, mls, mm, ok, sv, wt; -   Pastinaca sativa is a biennial herb, to 1.5 m tall from a fleshy taproot. Leaves alternate, base of stalk sheathing stem; irregularly pinnate, large, leaflets 5-15, opposite, 5-10 cm long, stalkless, margins toothed, lobed and /or divided; winter rosette attractive, dark green, often somewhat variegated. Flowers yellow, small, 5-parted, radially symmetrical, petals free, stamens […]
Pedicularis canadensis wood-betony; Canadian lousewort Orobanchaceae PECA; Bx, pb (D. Berg 2017); R (DeCandido 2001); -   Pedicularis canadensis is a perennial, hemiparasitic herb,  (Hedberg et al. 2005), stems hollow, clumped, 15-40 cm tall, hairy, gray-green, often tinged with red; from a short, thick rhizome, roots fibrous.  Leaves alternate, mostly basal, stalks often longer than blades; blade 5-15 cm long, 2-5 cm wide, narrowly oblong to elliptic, pinnately lobed, fern-like, lobes deeply […]
Peltandra virginica arrow arum Araceae PEVI; Bx, br, bz, sf, pb, vc; NY, ct; Q, a, j; R, e, gb, h, ml, o, rw, wp; -    Peltandra virginica is a perennial, aquatic, monocotyledon herb, to about 40 cm tall, stemless, colonial from thick rhizomes.  Leaves all basal, stalk 20-60 cm long often purplish, blade 10-45 cm long, 6-25 cm wide, arrow-shaped, with basal lobes flaring outwzard (hastate), thick, slightly fleshy, smooth, prominently 3-veined, from the insertion of the stalk, a central vein […]
Penstemon digitalis white beardtongue Scrophulariaceae PEDI(*); Bx, pb; R, h; -   Penstemon digitalis is an erect, unbranched herb 0.4-2 m tall, from rhizomes, stems shiny, hairless to very finely hairy, sometimes waxy-whitish or purplish.  Leaves opposite, stalks of winter rosette leaves to 8 cm long, stem leaves stalkless (sessile), blade 7-21 cm long, 2-4.5 cm wide, reduced in inflorescence grading into small bracts, tip pointed, base […]
Penthorum sedoides ditch stonecrop Crassulaceae PESE; Bx, pb; R, gr, h, is, w, wp; -   Penthorum sedoides is a perennial herb, to 70 cm, stems erect, banched above, hairless, sometimes reddish at nodes; colonial from stolons.  Leaves alternate, to 12 cm long, 3.5 cm wide (Yatskievych 2006) narrowly elliptic, pointed at both ends, margin toothed.  Flowers yellow-green, small, usually without petals, sepals 5, 0.1 cm long, persistent in fruit; stamens 10, […]
Petrorhagia prolifera childing pink Caryophyllaceae PEPR*; Q, j (Stalter and Lamont 2002); K; -   Petrorhagia prolifera is an annual herb, 30-60 cm tall, sparsely branched if at all.  Leaves opposite, 1-6 cm long, to 0.2 cm wide, linear, base sheathing stem to 0.2 cm, 3-veined.  Flowers pink, radially symmetrical; petals 5, 1–1.4 cm long, tip entire or notched, 1 dark vein; calyx 5-lopbed; stamens 10; ovary superior, styles 2, 1 […]
Petunia integrifolia petunia Solanaceae PEIN*; Bx, br; - Petunia integrifolia is an annual herb, apparently erect, ca 40 cm tall, all parts sticky (clammy)-hairy.  Leaves alternate, 3-8 cm long, elliptic to egg-shaped, margin entire, stalked.  Flowers dark purple, tubular, radially symmetrical, corolla tube ca 3 cm long, flaring at top; calyx 5-parted, lobes narrow, ca 2 cm long, often unequal; stamens dark purple with pink […]
Phlox divaricata forest phlox Polemoniaceae PHDI (*); Bx, pb, wv (Yost et al. 1991); R (DeCandido 2001); -   Phlox divaricata is a perennial herb 30-50 cm tall, base of stem often prostrate (decumbent), stems clumped but also sparingly colonial from basal stolons; roots associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves opposite, 2-5 cm long, 0.5-1.2 cm wide, narrowly egg-shaped to oblong, tip barely pointed or blunt.  Flowers usually pale blue-purple, sometimes red […]
Phlox paniculata garden phlox Polemoniaceae PHPA(*); Bx (DeCandido 2001); NY (DeCandido 2001); Q (DeCandido 2001); R, gb, lp; -   Phlox paniculata is a perennial herb to 2 m tall, forming clumps from woody root crowns.  Leaves opposite upper often sub-opposite, almost stalkless, blade 8-15 cm long, 1.5-4.5 cm wide, elliptic, to narrowly oblong, finely hairy below, margins hairy (ciliolate); lateral veins joining to form a vein near the margin of the blade.  Flowers pink-purple to […]
Phryma leptostachya lopseed Verbenaceae PHLE; Bx, pb (DeCandido 2001); Q, cu; - Phryma leptostachya is a perennial herb 0.4-1 m tall, erect, few-branched, stems 4-sided, purple, leafy, finely hairy, with a swollen area 0.3-1.2 cm long above each node; roots associated with VA mycorrhizas (Brundrett and Kendrick 1988).  Leaves opposite, each pair at right angles to next (decussate), lower leaf stalks 2-5 cm long, upper leaves often stalkless, […]
Physalis heterophylla clammy ground-cherry Solanaceae PHHE; Bx, wv (Yost et al. 1991); R, sm; -   Physalis heterophylla is a perennial herb 20-90 cm tall, colonial from deep, thick, fleshy rhizomes; stems erect to spreading, branching, upper parts sticky-hairy (viscid), hairs of different lengths, both glandular and nonglandular (Radford et al. 1968).  Leaves alternate, 3-11 cm long, 3-8 cm wide, rhombic, broadly egg- to lance-shaped, tip pointed, base rounded to slightly […]
Physalis virginiana Virginia ground-cherry Solanaceae PAVI; R, lp (in root ball of planted tree); -   Physalis virginiana is a perennial herb to 60 cm, colonial from rhizomes, stems much branched in a forked pattern, most parts minutely hairy, hairs short, curved (use lens).  Leaves alternate (sometimes appearing opposite), 4-10 cm long, narrowly egg or lance-shaped-shaped, minutely hairy, tip pointed, base narrowed, unequal or extending down stalk, margin sometimes with a […]
Physostegia virginiana  (Dracocephalium v.) obedient plant; false dragonhead Lamiaceae PHVI; R; - Physostegia virginiana is a perennial herb to 1.5 m, may be colonial from stolons, stems 4-sided, branched only near top.  Leaves opposite, stalkless, except sometimes the lowest pairs, these are soon deciduous; blade 5-15 cm long, 0.7-4.5 cm wide, much smaller on upper stem (Radford et al. 1968), elliptic or widest above middle, tip sharply pointed, […]
Phytolacca americana pokeweed Phytolaccaceae PHAM2; Bx, bg, br, bz, pb, sf, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw, n, wr; Q, a, cu, f, ft, j; K, do, fl, fs, m, ow, p; R, ah, ar, bg, bm, c, ca, cl, cp, cs, d, ev, h, hs, is, js, lp, ml, pm, pr, sv, w, wp, wt; -   Phytolacca americana is a perennial herb, 1-3 m tall, from a massive fleshy taproot sometimes to 15 cm wide, known to be toxic (Kingsbury 1964); roots associated with a community of mycorrhizal fungi principally Glomus spp. (Yuan Wei et al 2014). Stems stout, hollow, smooth, often partly red, becoming wine-red in age, primary stem […]
Picris hieracioides hawkweed oxtongue; cat’s-ear Asteraceae PIHI*; R, cp, mp, jw, k, mp, sv; -    Picris hieracioides is a biennial to short-lived perennial herb, to 0.2-1 m tall, usually short-bristly-hairy (hairs 2-pronged at ends, use lens), sap milky, stems erect, leafy (otherwise looking like a hawkweed), branched above (Radford et al. 1968).  Leaves alternate, 5-30 cm long including stalk (petiole), 1-5 cm wide, gradually reduced upwards from large rosette, lower […]
Pilea pumila clearweed Urticaceae PIPU; Bx, br, pb, sd, sf, wv (Yost et al. 1991); NY, iw; Q, cu, ks, j, rw; R, w; -   Pilea pumila is an annual herb 10-50 cm tall; translucent; smooth, pale green to pinkish in strong light; roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); Stipules  Leaves opposite, shiny, stalk about half as long as blade, ca over 2.5 cm long (Hilty 2006; Radford et al. 1968); blade 3-10 cm long, egg-shaped, coarsely […]
Pityopsis falcata  (Chrysopsis f.) falcate golden aster Asteraceae CHFA2; Q, j, tl; K, fl (Z. Wang 2016), m; -     Pityopsis falcata is a clumped, perennial herb, 10-35 cm tall, stem wooly-white, branched above.  Leaves alternate, linear, to 10 cm long, 0.5 cm wide.  Flowers yellow; arising in dense heads from the expanded top of the flower stalk (receptacle); the flowers very small, tubular; of two forms; a central dense cluster of more or less radially […]
Plantago arenaria  (P. indica, P. psyllium) sand plantain Plantaginaceae PLPS*; Q, j; K, pl; R, gw; - Plantago arenaria is a short-lived, annual herb,  white-wooly hairy, often slightly sticky, 10-60 cm tall, leafy stemmed, slender.  Leaves opposite, linear, 2-8 x 1-3 cm, basal in small plants, whitish-wooly.  Flowers in small, dense heads 0.5-1.5 cm, on axillary stalks, bracts dark, rounded, ovary densely white-hairy; flowering stems several to many, to 10 cm long; blooms and […]
Plantago aristata bracted plantain Plantaginaceae PLAR(*); Q, j, tl; K, fl (Z. Wang 2016); R, jl; -   Plantago aristata is an annual or short-lived, hairy, perennial herb.  Leaves basal, linear, to 18 cm long, base sheathing, dilated, papery.  Flowers white, very small, petals 0.2 cm, spreading; bract below each flower linear, elongate, conspicuous, the lower ones to 2.5 cm long, shorter above; inflorescence a wooly spike.  Fruit dry capsules with 2 seeds.  Wetland […]
Plantago Genus plantain Plantaginaceae - Plantago is a genus of low, stalkless, annual or perennial herbs. Leaves usually basal closely spiraled, but occasionally opposite along stem (P. psyllium); blade simple, with parallel veins, stalk expanded, wing-like or as an extension of the blade (phyllodial). Flowers small, green and membranous-brown, numerous, individually inconspicuous, 4-parted, sessile or nearly so surrounded by bracts, stamens often white; […]
Plantago lanceolata English plantain Plantaginaceae PLLA*; Bx, cn, nb, pb, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb, iw; Q, a, cu, f, fr, ft, j, ks, rw, tl, u, wl; K, cp, fl, p, pl; R, ar, c, cg, fs; bm, c, cs, gb, s, jl, js, k, mls, mm, wp; -   Plantago lanceolata is a perennial herb 10-40 cm tall, roots fibrous.  Leaves all basal, ascending, narrow with prominent parallel veins, to 40 cm long, 4 cm wide; inflorescence stalk to 50 cm tall.  Flowers small, inconspicuous, amid bracts; white stamens somewhat conspicuous; inflorescence a narrow spike to 8 cm long to almost 1 cm wide, brown, wooly. densely […]
Plantago major common plantain Plantaginaceae PLMA*; Bx, cn, sf, sn, up, vc, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct, hb; Q, a, cu, f, fr, ft, i, j, wl; K, fl, fs, p; R, ar, bd, bg, c, cs, fk, h, is, jl, js, jw, k, lp, mm, sv, w, wp; - Plantago major is a perennial C3 herb (Pooter et al. 1990), fibrous rooted from a short rootstock (caudex).  Leaves all basal, with spiral rosette formation, wide, egg-shaped (ovate), mostly entire, to 18 cm long, 11 cm wide, leaf stalk bases usually green sometimes red, usually finely hairy (use lens) hairy; flower stalk to 25 cm. Flowers  very […]
Plantago maritima  (P. juncoides) seaside plantain Plantaginaceae PLMA; Q; - Plantago maritima is a perennial herb from deep roots.  Leaves alternate, all basal, strongly ascending, linear, thick, fleshy to 15 cm long.  Flowers dry, papery, individually inconspicuous, in spikes 2-10 cm, usually interrupted below, petal lobes about 0.1 cm long, bracts broadly egg-shaped, tips pointed, about as long as calyx; flowering stem 5-20 cm, hairy above, as […]
Plantago rugelii black-seeded plantain; red-stemmed plantian Plantaginaceae PLRU; Bx, pb, sf, wv (Yost et al. 1991); Q, j; R; -   Plantago rugelii is an herb much like P. major.  Leaves generally pale green, base of leaf stalk usually red, not hairy.  Flower bracts narrow with tapered tip, sepals egg-shaped, sharply keeled, membranous margins much narrower than keel.  Fruit capsule 0.4-0.6 cm long, seeds 0.15 cm long, dull, blackish.  Wetland status: FACU.  Frequency in NYC: More common than […]
Platanthera lacera  (Habenaria l.) green fringed orchid Orchidaceae HALA; Q, j (Stalter and Lamont 2002); K (D. Taft personal communication 7/2015); R (DeCandido 2001);  -    Platanthera lacera is a perennial monocotyledon herb,  40-80 cm tall, stem leafy.  Leaves alternate, 5-15 cm long, 3-5 cm wide, lance-shaped to narrowly oval, tip pointed to blunt, upper leaves much smaller, almost linear.  Flowers greenish-white to yellow-green, bilaterally symmetrical, two lateral petals and uppermost sepal about 0.5-0.7 cm long, together forming a hood at top of […]
Pluchea odorata  (P. purpurascens) annual marsh-fleabane Asteraceae PLOD; Bx, g, pb; Q, j; K; R, go, gr, sm, t; -   Pluchea odorata is an annual herb, to 60m (usually less than 40 cm); hairy, aromatic when crushed.  Leaves alternate, elliptic, 4-15 cm long, 1-7 cm wide, tip pointed, margin toothed.  Flowers pink-purple, tiny, no ray flowers, in numerous small, narrow heads about 0.7 cm long, basal bracts (involucre), hairy, overlapping in several rows; inflorescence of flat-topped […]
Podophyllum peltatum mayapple Berberidaceae POPE3; Bx, br, pb, sf, wv (Yost et al. 1991); NY, iw; Q, a; K, p (planted?); R, bd, d, h, gb;  - Podophyllum peltatum is a perennial, summer green herb (Hicks and Chabot 1985), colonial from a rhizome, roots associated with VA mycorrhizas (Brundrett and Kendrick 1988); stems erect, to 50 cm, large leaves form dense layer that shades out competing vegetation, contains cytotoxic resin, Podophyllotoxin, with violently cathartic effects (Davidson and Forman 1982; Kingsbury 1964), light […]
Polemonium vanbruntiae Jacob’s ladder Polemoniaceae POVB; R, t; -   Polemonium vanbruntiae is a perennial herb to 1 m tall, erect, upper internodes elongate.  Leaves alternate, pinnately compound, leaflets 7-17, narrow, 2-4 cm long, tips pointed.  Flowers blue, regular, to 2 cm long, 5 petal lobes, stamens longer than funnel-shaped petal tube.  Wetland status: FACW.  Frequency in NYC: NYS Rare, G3, S3, T. Possibly still at one […]
Polygala cruciata cross-leaf milkwort Polygalaceae POCR; R; -    Polygala cruciata is an annual herb to 30 cm tall, branches few or none.  Leaves in whorls or 3-4, linear, to 4 cm long, 0.5 cm wide, often widest above middle, tip blunt. Flowers purplish, irregular, to 0.6 cm in a dense spike-like, cylindrical cluster to 6 cm long, 1.5 cm wide, at top of plant; […]
Polygala lutea orange milkwort Polygalaceae POLU; R; -   Polygala lutea is a biennial or perennial herb to 40 cm tall, stems often clustered.  Leaves of basal rosette widest above middle, to 5 cm long, stem leaves becoming narrower and smaller upwards to 3 cm.  Flowers orange, irregular, to 0.7 cm, in dense, head-like clusters to 3 cm long, 1.8 cm wide at the end […]
Polygala sanguinea rose milkwort Polygalaceae POSA; R; - Polygala sanguinea is an annual herb to 40 cm tall, stem erect.  Leaves alternate, linear to narrowly elliptic to 4 cm wide 0.1 cm wide.  Flowers rose-purple, white or greenish, irregular, to 0.5 cm, in dense rounded or cylindrical heads to 2 cm long on a stalk to 2 cm long; blooming July-Sept. Fruit a capsule seeds with […]
Polygala verticillata whorled milkwort Polygalaceae POVE; Bx; R; - Polygala verticillata is an annual herb to 40 cm tall, branches divergent.  Leaves in whorls of 2-5, linear, to 2 cm long, to 0.3 cm wide.  Flowers white or greenish, small, irregular (somewhat pea-flower-shaped), sepals 5, petals 3, fused below, one larger than other two, fringed; inflorescence of opposite or whorled dense, cylindrical to conical, racemes.  Fruit a capsule, […]
Polygonatum biflorum smooth Solomon’s seal Liliaceae POBI; Bx, cf, pb, rd, sf, vc; NY, hb, iw; Q, a, c, cu, ft; K, p (planted?); R, bd, cl, cs, d, eb, gb, h, js, lt, mls, ro, sv, w, wp; - Polygonatum biflorum is a perennial monocotyledon herb from a knotty rhizome, sparsely colonial, stem 0.4 to 1.2 m tall, unbranched, nodding.  Leaves alternate, stalkless, ranked along stem, blade 5-15 cm long, 1-8 cm wide, narrowly elliptic to oval, tip pointed, base often clasping, hairless, pale matte blue-green above, pale-waxy greenish-white below, veins 7-19, conspicuous (but much […]
Polygonatum pubescens hairy Solomon’s seal Liliaceae POPU2; Bx, br, vc; NY, hb; Q, cu; R h, wt; -   Polygonatum pubescens is a perennial monocotyledon herb, colonial from short rhizomes, roots sparingly associated with VA mycorrhizas (Brundrett and Kendrick 1988), stem unbranched, nodding, 50-90 cm tall.  Leaves alternate, 2-ranked, short-stalked, blade 4-12 cm long, 1-6 cm wide, narrowly elliptic to broadly oval, pointed at both ends, veins 3-9, pale, waxy below, finely hairy on […]
Polygonella articulata jointweed Polygonaceae POAR4; Q, j; K, gt, m, pl; R; - Polygonella articulata is an annual herb, slender, wiry, to 50 cm tall from a taproot, pale-waxy, branched above, leaf sheaths truncate at each node; branches appear jointed at outer ends. Winter plant reddish-brown. Stipule (ocrea) sleeve-like around stem above leaf stalk (Flora of North America 1993+).  Leaves linear, alternate, edges rolled back, to 2 cm long, […]
Polygonum amphibium water smartweed Polygonaceae POAM; Q; cu, f; R;  -   Polygonum amphibium is a perennial herb from rhizomes, to 1 m tall, erect or floating aquatic, ocreae often fringed, those above water often forming a flared collar .  Leaves alternate, those of aquatic form elliptic, blunt or rounded, dock-like, leaves of terrestrial form narrow, hairy, long-pointed.  Flowers pink or red, to 0.5 cm, to 0.7 cm […]
Polygonum arenastrum door weed Polygonaceae POAR2*; Bx, br, cn, pb; NY, ct, rr, wr; Q f, ft, j, lk; K, fs, pl; R, fk, lc, lp; -   Polygonum arenastrum is an annual herb, to 10 cm tall, taprooted, freely branched, sprawling to reclining, mat-forming; stipules (ocreae) sheath-like, membranous, 2-parted, becoming  ragged.  Leaves alternate, stalk short, jointed at juncture with basal sheath; blade 0.5-2 cm long, 0.3-0.9 cm wide cm, elliptic, dark bluish-green, often deciduous late in season, leaves.  Flowers green with white or […]
Polygonum arifolium halberd-leaved tearthumb Polygonaceae POAR; Bx, pb, sf; R, t; -   Polygonum arifolium is an annual vining herb, 1-2 m, stem with hooked prickles, slender, reclining on other vegetation; ocreae membranous.  Leaves alternate, arrow-shaped, to 20 cm long, 15 cm wide, basal lobes triangular, divergent, hairs in tiny cushions below.  Flowers pink, white or green, radially symmetrical, 5-parted, fused at base, petals (tepals) 0.25 cm, rounded on […]
Polygonum aviculare prostrate knotweed Polygonaceae POAV*; Bx, pb, sd, wv (Yost et al. 1991); NY, bl (Stalter and Tang 2002), ct; Q, f, j, ri; R, c, is, js; -   Polygonum aviculare is a weedy taprooted annual herb to 10 (20) cm, freely branched, prostrate or sprawling to almost erect; nodes with membranous sheaths (ocreae) 0.4-0.8 cm, becoming tattered strips; node sheath membranous, becomng shredded.  Leaves alternate, of several sizes, early leaves larger, 2.5-6 cm long, 0.4-1.5 cm wide, lance-shaped, later leaves and those of […]
Polygonum caespitosum var. longisetum smartweed Polygonaceae POCE*; Bx, br, bz, cn, pb, sd, sf, sl, up, vc, wv (Yost et al. 1991); NY, ct, hb; Q, a, cu, f, ft, lk, ri; K, ow, p; R, ar, bg, bm, c, cl, d, gr, h, js, sv, w, wp; -   Polygonum caespitosum var. longisetum is a weedy annual herb to 1 m tall, (more commonly 30 cm or less), stems slender, often pinkish, or reddish, branched, reclining.  Leaves alternate, thin, dark green, narrowly elliptic, tapering at both ends, almost stalkless, margins and veins below finely fringed (ciliate, use lens); node sheaths with long bristles 0.5-1.0 […]
Polygonum cuspidatum  (Fallopia japonica, Reynoutria j.) Japanese knotweed Polygonaceae POCU*p; Bx, bg, br, bz, cf, ht, pb, rd, sf, sn, up, vc, wv (Yost et al. 1991); NY, ct, hb, iw, n, wr; Q, a, cu, dp, f, fr, i, j, lk, rb, rw, tl, u, wl; K, do, fs, vb; R, ah, ar, bd, bg, bk, bm, c, ca, cb, cg, cl, cs, d, ev, fk, gr, h, is, js, jl, k, lc, lp, lt, mc, mm, ok, pm, pr, r, se, sm, sp, t, v, w, wp, wt, x; -   Polygonum cuspidatum is a large Perennial herb, to 3 m tall; extensively colonial from rhizomes, also forming large root-crowns; stems stout, , cylindrical, internodes hollow, nodes prominent, bamboo-like.  Leaves alternate broadly egg-shaped, tip pointed, base truncate to very shallowly lobed with small angles, to 15 cm long, 10 cm wide.  Flowers white, 5-parted (tepals), radially symmetrical, […]
Polygonum erectum erect knotweed Polygonaceae K, p (Z. Wang); - Polygonum erectum is an annual to 50 cm tall, branched; a membranous leaf sheath (ocreae), 0.4-1 cm long, surrounds the plant stem just above the leaf stalk (petiole).Stems erect, to prostrate and upturned at ends of branches. Leaves green to bright yellow-green, small, of differing sizes, (heterophyllous) the larger, stem leaves,  3-6 cm wide, 1-3 cm long, those […]
Polygonum Genus [herbs] knotweed; smartweed Polygonaceae - Polygonum is a genus annual or perennial herbs (ours) and vines. Stipules consist of a membranous sheath below each leaf (ocreae), the upper margins are often bristly.  Leaves usually alternate, simple (1-parted), margins smooth (entire).  Flowers small, petals and sepals alike (tepals). Ovary attached above tepals (superior).  Fruit consists of developed seed (achene), flat or 3-sided. 
Polygonum glaucum seaside knotweed Polygonaceae POGL; Q, rb; K; -   Polygonum glaucum is an annual herb to 30 cm long, prostrate but branch tips upturned, very pale gray-green, leaf sheaths encircling nodes, dark reddish-brown, the margin whitish, bristle-fringed, 0.7-1.0 cm.  Leaves alternate, lance-shaped 1-3 cm long, 0.2-0.8 cm wide.  Flowers pale pink-white, tepals with green midrib, 0.2-0.4 cm, in small axillary clusters; blooming and fruiting July-Oct. […]