Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, east across most of North America to the Atlantic Coast.

Habitat: Weed of disturbed ground.

Flowers: May-November

Origin: Introduced from Europe

Growth Duration: Annual

Conservation Status: Not of concern

Pollination: Bees, wasps

Glabrous annual, the stem erect, freely branched, 1-3 dm. tall.

Lower leaves alternate, 1-3 cm. long, rhombic-ovate to rhombic-obovate, narrowed abruptly to very slender petioles 3-10 mm. long; floral leaves opposite, short-petiolate, broadly ovate, 10-25 mm. long.

Inflorescence of cymes terminal on the branches; flowers tiny, monoecious, borne in involucres; staminate flowers numerous, naked, each consisting of a single stamen; pistillate flower single and terminal in the involucre; involucres 1-1.5 mm. long, bearing 4 glands with long, slender horns.

Capsule smooth, 2.5 mm. long, separating into three 1-seeded segments.