Plants 3-8 dm, crisp-pubescent, glabrate or glabrous with age. Stems sparingly branched. Leaves 4-12 × 2-5 cm; blade ovate to oblong-lanceolate, subcordate to oblique basally, abaxial surface and margins moderately pubescent, hairs scattered, flattened, apex acute to short-acuminate, with 7-9 prominent veins. Flowers 1-2(-3); perianth narrowly campanulate; tepals creamy to greenish white, narrowly oblanceolate, 8-15 mm; stamens mostly exserted; filaments filiform, 10-15 mm; anthers 3-4(-5) mm; ovary broadly ovoid to obovoid, becoming 3-lobed and obpyriform after anthesis, finely papillose, ovules 2-6 per locule, horizontal; style 0.9-1.2 cm, glabrous or pubescent; stigma unlobed or 3-lobed. Berries reddish orange to bright red, 6-12(-18)-seeded, depressed-globose, 12-18 mm, strongly papillose. Seeds 4-5 mm. 2n = 22.
Flowering late spring--summer. Rich, shady deciduous forests, aspen groves to open coniferous forests; 300--2500 m; Alta., B.C., Man., Ont., Sask.; Ariz., Colo., Idaho, Mich., Minn., Mont., Nebr., N.Mex., N.Dak., Oreg., S.Dak., Utah, Wash., Wyo.
The recently discovered populations of Prosartes trachycarpa in Isle Royale National Park, Michigan (E. J. Judziewicz et al. 1997), are noteworthy disjunctions for this otherwise western species.
General: Perennial, 30-80 cm tall; stems nearly erect, sparsely branched, weakly puberulent; rhizomes slender.
Leaves: Cauline, alternate, ovate, ovate-oblong, 4-12 cm long, 2- 5 cm wide, prominently veined, glabrous above, somewhat pubescent and paler below, margins entire, moderately ciliate, base somewhat cordate to oblique, apex acute to shortly acuminate; blades sessile.
Flowers: Inflorescence a terminal panicle, pyramidal in outline; flowers numerous, 3-parted, tepals inconspicuous, narrowly oblong, 0.5-1 mm long, white; stamens erect, the filaments broad at the base, sometimes as broad as the tepals; flowers May-July.
Fruits: Berry, globose, 7-10 mm long, orange to red, strongly papillose.
Ecology: Shady, forested habitats, along streams; 1700-10000 m (5500-10000 ft); Apache, Cochise, Coconino, Gila, Graham, Mohave, Pima, counties; south-central and southwestern Canada, western to southwestern U.S.
Notes: Streptopus amplexifolius (claspleaf twisted stalk) is similar in appearance to P. trachycarpa, but is differentiated by the leaf base strongly cordate- clasping; inflorescence of 1-2 flowers arising in the axils of the leaves, these with a peduncle abruptly transitioning to pedicel; berry oval to elliptic in outline, 10-12 mm long, smooth, whitish green maturing to yellowish orange or red. It has been reported in our area only in moist conifer forests in the White Mountains of Apache County.
Editor: Springer et al. 2008
