Plants with slender creeping rhizomes, these becoming apically enlarged and scaly; stem 2-8 dm, loosely villous or puberulent and commonly somewhat viscidulous; lvs all cauline, mostly 10-22 below the infl, thin, glabrous or slightly scabrous above, viscidulous-puberulent beneath, at least along the larger veins, the lower reduced and soon deciduous, the others elliptic or obovate, acuminate, ±sharply and saliently few-toothed, tapering to a sessile or shortly petiolar base, often forming a pseudowhorl beneath the infl, the largest ones 6-17 נ(1.5-)2-6 cm; heads several or many in an open, slenderly branched, sparsely subulate-bracteate, mostly corymbiform infl; invol 6-9 mm, its slender, sharply pointed bracts well imbricate, thin, pale stramineous to faintly greenish or somewhat purple-tinted, scarcely herbaceous, the outer ciliate-margined, otherwise glabrous; rays 10-21, white or faintly pinkish, 9-15 mm; achenes copiously glandular; 2n=18. Woods; Nf., Que., and s. Ont. to N.J., N.Y., and Pa., and s. in the mts. to n. Ga.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.