Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across all but the southwestern U.S. to the Atlantic Coast.
Habitat: Streamsides, ponds, lakes, ditches and other moist to wet waste places.
Origin: Introduced from British Columbia
Conservation Status: Not of concern
Annual, nearly glabrous throughout, 3-15 dm. tall.
Leaves with petioles 1-6 cm. long, pinnately compound, with 3-5 lanceolate, pointed, serrate leaflets up to 10 cm. long and 3 cm. wide.
Heads without rays, the disk about 1 cm. wide; outer involucral bracts 10-16, green and leafy, surpassing the pale yellow disk.
Achenes flat, narrowly wedge-shaped, usually olivaceous, 5-10 mm. long, with persistent pappus of 2 barbed awns.