Distribution: Widely distributed throughout much of Washington; Alaska to California, east to Idaho and Montana.
Habitat: Common in moist areas at mid- to high elevations in the mountains.
Conservation Status: Not of concern
Fibrous-rooted perennial from a stout, branched rhizome, the unbranched stem usually glabrous, 3-12 dm. tall.
Leaves opposite, chiefly cauline, 2-5 pairs, the lowermost 1-2 pairs reduced, the others well-developed, petiolate, pinnatifid, the enlarged terminal segment up to 10 cm. long and 7 cm. wide, the 1-4 pairs of lateral segments up to 7.5 cm. long and 4.5 cm. wide; upper leaves reduced and sub-sessile; all leaves and their segments usually wavy margined.
Inflorescence compact, 2.5-8 cm. wide, becoming diffuse in fruit; flowers all perfect; calyx enlarging and spreading, with 12-20 plumose, bristle-like segments; corolla united, white, 4.5-7 mm. long, the 5 lobes less than half as long as the tube; stamens 3, well exerted; ovary inferior, with two of the three cells vestigial.
Fruit an achene, 3-6 mm. long, ovate-oblong to ovate, glabrous.