Distribution: Chiefly east of the Cascades, but widespread in western United States, to Texas and the Dakotas
Habitat: Weedy native in dry areas at low elevations
Conservation Status: Not of concern
Monoecious, branching annual, 1-8 dm. tall, coarsely rough-hairy.
Leaves mostly alternate, petiolate, bipinnatifid, the blade 2-8 cm. long.
Heads numerous in elongate, terminal racemes, sometimes chiefly staminate or chiefly pistillate; staminate heads 2-4 mm. wide, short-pedunculate, not subtended by leaves; pistillate involucres solitary or clustered in the upper leaf axils, the burs 5-10 mm. long, with several series of flattened, divergent spines