Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Noxious weed in fields and waste ground in eastern Washington.
Origin: Introduced from Europe
Conservation Status: Not of concern
Glabrous annual, biennial or occasionally perennial, nearly scentless herb, 1-6 dm. tall.
Leaves 2-8 cm. long, bipinnatifid, the ultimate segments mostly elongate, linear or liner-filiform.
Heads several or numerous, the disk 8-15 mm. wide; involucral bracts dry, in 2 series, the margins translucent; rays 12-25, white, 6-13 mm. long; disk flowers yellow, 5-toothed; receptacle hemispheric, naked; pappus a short crown.
Achenes roughened, with 2 marginal and 1 ventral thickened ribs.