Renouée prolifique

Polygonum ramosissimum var. prolificum Small, Bull. Torrey Bot. Club 21: 171. 1894; P. prolificum (Small) B. L. Robinson; P. prolificum var. autumnale (Brenckle) Brenckle; P. prolificum var. profusum Brenckle

Plants bluish green when fresh, dark brown or black after drying, homophyllous. Stems 10-80 cm. Leaf blades bluish green, oblanceolate, 8-30(-35) × 4-6 mm, apex rounded or obtuse; stem leaves 1-2.5(-3.5) times as long as branch leaves; distal leaves overtopping flowers. Inflorescences axillary; cymes uniformly distributed or crowded toward tips of branches, 2-4-flowered. Pedicels enclosed in ocreae, 1-2 mm. Flowers: perianth 2-2.8(-3) mm; tepal margins white or pink; stamens 3. Achenes enclosed in or exserted from perianth, 1.6-2(-2.4) mm, shiny or dull, smooth, roughened, or obscurely tubercled; late-season achenes 4-10 mm. 2n = 60.

Flowering Jul-Nov. Wet, saline places; 0-2000 m; Alta., B.C., Man., Ont., P.E.I., Que., Sask.; Ark., Calif., Conn., Del., Idaho, Ill., Iowa, Kans., Ky., La., Maine, Md., Mass., Minn., Miss., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Okla., Oreg., Pa., R.I., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wyo.