Plants from thick rhizomes. Stems freely branched, stout, 5-12 dm, often with reddish hairs basally, nodes not fringed. Leaves 5-15 × 2.5-6 cm; blade ovate-oblong to oblong-lanceolate, base cordate-clasping, apex acuminate; peduncle: junction with pedicel abrupt, with glands indicating transition, entire structure 2-5 cm, glands short-stalked. Flowers 1-2 per axil; perianth campanulate; tepals spreading, recurved at tips, white to greenish yellow, narrowly oblong-lanceolate, 9-15 mm; stamens unequal, outer shorter, 0.8-1 mm, inner 2-3 mm; anthers lanceolate, 3-3.5 mm, apex 1-pointed; style stout, 4-5 mm; stigma fused from base to tip, unlobed; combined peduncles and pedicels recurved, 2-5 cm, short-stalked glands indicating transition; pedicel sharply geniculate, glabrous. Berries whitish green maturing to yellowish orange or red, ellipsoid, 10-12 mm. Seeds 2.5-3 mm. 2n = 16, 32. Flowering late spring--mid summer. Rich moist coniferous and deciduous woods; 0--2800 m; Greenland; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S, Ont., P.E.I., Que., Sask., Yukon; Alaska, Ariz., Calif., Colo., Conn., Idaho, Maine, Mass., Mich., Minn., Mont., N.H., N.Mex., N.Y., N.C., Oreg., Pa., S.Dak., Tenn., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Eurasia. Several poorly defined races described by N. C. Fassett (1935) as varieties based chiefly on minute difference in leaf-margin serration are not here recognized.
Stem 4-10 dm, glabrous except near the base; lvs ovate-oblong or lance-ovate, acuminate, cordate-clasping, entire or very minutely toothed, the main ones 6-12 נ2-5.5 cm; free part of the peduncle and pedicel together 3-5 cm, jointed at about two-thirds of its length, above the joint
1-fld (or sometimes 2-fld) and abruptly deflexed or twisted; tep greenish-white, 1 cm, spreading from near the middle; anthers 1-pointed, those of the outer series much longer than the filaments; stigma entire or barely 3- lobed; fr red, mostly ellipsoid, 1.5 cm; 2n=32. Rich moist woods; circumboreal, in Amer. s. to Mass., N.Y., Mich., Wis., and Minn., and in the mts. to N.C. and Ariz. Our plants are var. americanus J. A. Schult.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.