Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska, south to Oregon, east to Alberta, Idaho, and Montana.
Habitat: Streambanks and other moist, shaded places.
Conservation Status: Not of concern
Single-stemmed perennial with milky juice, the stem 1.5-8 dm. tall, with fine, woolly hairs in the inflorescence, otherwise glabrous.
Leaves alternate, thin, the lower petiolate, the petiole often wing-margined, the blade deltoid to sagittate, irregularly toothed, up to 12 cm. long and 11 cm. wide; upper leaves reduced and narrower, tapering to a sessile or short-petioled base.
Inflorescence open and flat-topped, with several heads; heads 10- to 15-flowered, the corollas all ligulate, white or purplish; involucre 10-13 mm. high, with about 8 principlal bracts; pappus of numerous, off-white, capillary bristles.
Achenes elongate, cylindrical, glabrous.