Taprooted, several-stemmed perennial 2-4(-5) dm, ±pubescent with long or short, appressed or spreading hairs; lvs numerous, nearly alike, oblong-elliptic to linear- oblanceolate, acute to rounded, seldom over 5 נ1 cm, mostly entire, the lower tending to be short- petiolate, the lowermost deciduous; heads several, the invol 5-10 mm, ±strigose or hirsute and sometimes also glandular, its bracts regularly imbricate, gradually tapering to a point, often purple-tipped; rays mostly 10-35, 6-10 mm; achenes narrowly obovate, 3-5-nerved; 2n=18, 36. Dry, open, often sandy places; Minn. to Mo., w. to B.C., Calif., and Tex. July-Oct. (Heterotheca v.) Two or more vars. with us, others farther w.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.