Fibrous-rooted from a short rhizome or caudex; stem 10-15 dm, glabrous and glaucous; lvs opposite, narrowly ovate to triangular, coarsely toothed, mostly 13-25 נ5-10 cm, scabrous above, scabrous or hispid beneath, truncate or broadly rounded at base, or the lower cordate, on petioles 1.5-4.5 cm; heads rather numerous on slender peduncles in an open infl, relatively small, the disk ca 1 cm wide, with 4-6(-8) rays 1-1.5 cm; invol bracts glabrous except the ciliate margins; 2n=14. Woods in the Cumberland Plateau region; Ky. and Tenn. to Ala. and Ga. July-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.