Annual, erect, freely branched, 1-4 dm, the stems soft-hairy; petioles 4-10 mm, exceeded by the subulate tips of the stipules; lfls narrowly oblanceolate, 1-2 cm, serrulate only at the tip; heads densely fld, ovoid to cylindric, 1-3 cm, on peduncles 1-3 cm; cal densely villous with hairs to 2 mm, the tube 1.5-2 mm, the setaceous lobes 3-5 mm, surpassing and partly concealing the small, whitish or pinkish cor; 2n=14. Native of Eurasia and n. Afr., found as a casual weed of roadsides and waste places, especially in light, sandy soil, throughout much of the U.S. and s. Can. May-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.