Stems sparsely to densely hirsute. Leaves pilose. 2n = 32, 40, 48.

Flowering Aug–Oct. Open, often disturbed, dry to wet, sandy or rocky soils, prairies, old fields, sandy shores, bluffs and ridges, open deciduous woodlands, hammocks, roadsides; 0–1000+ m; B.C., N.B., N.S., Ont., Que.; Ala., Ark., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., Maine, Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., S.C., S.Dak., Tenn., Va., Wis.; introduced in Europe.

Variety pilosum is sometimes considered an agricultural weed (J. G. Chmielewski and J. C. Semple 2001b). It is introduced in British Columbia, New Brunswick, and Nova Scotia.