Stems (gray to white) mostly simple, 30-80 cm, tomentose. Leaves gray; blades linear to narrowly elliptic, 3-11 cm, margins plane (proximalmost entire or apically lobed, lobes to ¹/3 blade lengths; cauline 1.5-11 × 1-1.5 cm, entire or lobed to pinnatifid), faces densely tomentose. Heads in congested, paniculiform or racemiform arrays 5-30 × 1-4 cm. Involucres 3-4 × 2-4 mm. Florets: pistillate 5-12; bisexual 6-30; corollas 1.9-2.8 mm. 2n = 18, 36. Flowering mid summer-late fall. Disturbed roadsides, open meadows, rocky slopes; 100-3000 m; Alta., B.C., Man., N.B., Ont., P.E.I., Que., Sask.; Ala., Ariz., Ark., Calif., Colo., Conn., Del., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Penn., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., Wis., Wyo. Subspecies ludoviciana is widespread in North America in diverse habitats. It is the most common subspecies and the most variable morphologically.