Mem. Boston Soc. Nat. Hist. 4: 89. 1888.
Herbs perennial, caulescent, rhizomes present long, stolons absent, bulbs absent. Aerial stems 1(–3) from base, mostly erect, 10–25 cm, herbaceous, sparsely to moderately villous, hairs nonseptate and usually septate. Leaves cauline; stipules rudimentary; petiole (2–)3–5(–6) cm, hairs septate and nonseptate; leaflets 3, green, obcordate, (8–)10–16(–20) mm, lobed 1/5–1/3 length, margins green, surfaces glabrous to sparsely strigose, oxalate deposits absent. Inflorescences umbelliform cymes, 1–3-flowered; peduncles (2–)4–8(–10) cm. Flowers tristylous, above level of leaves; sepal apices without tubercles; petals yellow, 12–20 mm. Capsules oblong-cylindric, 10–15 mm, densely puberulent. 2n = 24.
Phenology: Flowering May–Aug.
Habitat: Open woods, fir, Douglas fir-oak woodlands, dry shrublands, roadsides, disturbed areas.
Elevation: 0–700 m.
B.C., Calif., Oreg., Wash.