Perennials; glabrous or hirsute. Rhizomes (tuberiform, fragile), ovoid or globose at base of stem, 3-10 mm diam., (fleshy). Stems (simple from base), erect to ascending, (not flexuous), unbranched or branched distally, 1-5 dm, glabrous or pubescent proximally. Basal leaves not rosulate, pinnately compound, (3 or) 5 (or 7)-foliolate, 2-10 cm, leaflets petiolulate or subsessile; petiole 0.5-6.5 cm; lateral leaflets petiolulate or subsessile, blade similar to terminal, ovate, smaller, margins entire; terminal leaflet (petiolule 0.03-0.18 cm), blade orbicular to broadly ovate or subcordate, 0.5-2 cm × 7-25 mm, base cordate to rounded, margins entire or repand, (surfaces glabrous). Cauline leaves 3-7, (3 or) 5 or 7-foliolate (middle ones 5 or 7-foliolate, smaller distally, becoming 3-foliolate), petiolate; petiole 0.5-3 cm, base not auriculate; lateral leaflets similar to terminal, smaller; terminal leaflet blade obovate to oblanceolate, 0.5-2.6 cm × 3-13 mm, margins shallowly toothed, entire, or repand. Racemes ebracteate. Fruiting pedicels divaricate-ascending, 7-18 mm. Flowers: sepals oblong, 1.7-2 × 1-1.2 mm, lateral pair not saccate basally; petals white, oblanceolate, 4-6 × 1.5-2 mm, (not clawed); filaments: median pairs 2-2.5 mm, lateral pair 1-1.5 mm; anthers ovate, 0.3-0.5 mm. Fruits linear, (torulose), 1.5-3.3 cm × 1.7-2.2 mm; (valves glabrous or sparsely pubescent); ovules 18-40 per ovary; style 0.5-1.5 mm. Seeds brown, ovoid, 1-1.6 × 1-1.2 mm. 2n = 64.

Flowering Apr-Jul. Muddy grounds, lake margins, shallow streams, meadows; 150-1500 m; B.C.; Alaska, Calif., Oreg., Wash.