Native. Annual. Propagates by seeds.
Time of bloom: August to October.
Seed-time: September to November.
This native American has established itself in Europe, where it is very cordially disliked. Stem one to six feet or more tall, erect, smooth, purple, branching freely. Leaves deep green, usually undivided or some of the lower ones three-cleft, narrowly lance-shaped, coarsely toothed, with long, slender petioles. Heads about a half-inch broad, numerous, on short, slender peduncles, the outer bracts of the involucre few, obtuse, entire, extending not far above the head; rays usually wanting, but, when present, golden yellow; disk florets orange-yellow, five-lobed. Achenes dark brown, rather thick, wedge-shaped, tubercled, four-angled, four-awned, or the outer row flattened on one side and three-awned, the sides of achene and awns downwardly barbed.
Drainage and cultivation of the ground; prevention of seeding by frequent, close cutting.