Annual or rarely biennial, 6-15 dm, amply leafy; stem hirsute, the hairs spreading except near the top; basal lf-blades elliptic to suborbicular, coarsely toothed, to 10 נ7 cm, ±abruptly long-petiolate; cauline lvs numerous, broadly lanceolate or broader, all except sometimes the uppermost usually sharply toothed; heads several to very numerous; invol 3-5 mm, finely glandular and sparsely beset with long, flattened, transparent hairs; disk 6-10 mm wide; rays 80-125, white or rarely anthocyanic, 4-10 נ0.5-1.0 mm; disk-cors 2.0-2.8 mm; achenes 2-nerved; pappus of the disk-fls double, with 10-15 bristles and several very short, slender scales (visible at 20x), that of the rays-fls of short scales only; 2n=27, 54. A weed in disturbed sites over most of the U.S. and adj. Can., more common northward.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Infrequent to frequent in open woods and clearings throughout the state. Also a frequent to common weed in hayfields and waste cleared grounds and along roadsides. In some hayfields it is an obnoxious weed.