Perennials; glabrous or sparsely pubescent. Rhizomes cylindrical, slender, to 2 mm diam. Stems erect, unbranched, (1.5-)2.5-8.5(-10) dm, sparsely to densely hirsute at base. Rhizomal leaves 3 (or 5)-foliolate, (4-)7-20(-22) cm, leaflets petiolulate or subsessile; petiole (2-)4-12(-14) cm; lateral leaflets subsessile, blade similar to terminal, larger or smaller in size; terminal leaflet petiolulate [(0.3-)0.5-1.5 cm], blade ovate to broadly lanceolate, 1.5-7(-9) cm, base usually cuneate, rarely subreniform or obtuse, margins 3-5(-7)-lobed or -toothed, surfaces puberulent. Cauline leaves (3 or) 4-8, 3 (or 5)-foliolate, petiolate, leaflets petiolulate or sessile; petiole 1-4 cm, base not auriculate; lateral leaflets sessile, blade similar to terminal, smaller, margins usually dentate, rarely entire; terminal leaflet sessile or petiolulate, blade broadly ovate to narrowly lanceolate, 2-7 cm × 6-40 mm, margins minutely pubescent. Racemes ebracteate. Fruiting pedicels ascending to divaricate, (9-)12-25 mm. Flowers: sepals oblong, 2.5-4 × 1.3-2 mm, lateral pair saccate basally; petals usually white, rarely pinkish, obovate, 8-15 × 4-8 mm (clawed, apex rounded or emarginate); filaments: median pairs 3.5-6 mm, lateral pair 2-3.5 mm; anthers oblong, 0.8-1.2 mm. Fruits linear, 1.5-3.2 cm × 1.4-2 mm; ovules 10-16 per ovary; style (0.5-)1-4 mm. Seeds dark brown, oblong, 1.8-2.3 × 1-1.2 mm. 2n = 40.

Flowering Apr-Jun. Moist ground, stream banks, swampy or damp woods, thickets, wet meadows; 0-900 m; B.C.; Alaska, Calif., Oreg., Wash.