Stem usually spreading-hispid, varying to largely glabrous; many or most of the lvs sessile, only the lower or lowermost ones evidently petiolate; lower lf-surface, at least along the midrib, relatively long- hairy; heads with fewer (mostly ca 8 or ca 13) rays; invol usually finely hairy, varying to glabrous; scattered stations in the mts. and adj. piedmont of Va., W.Va., and N.C. (S. connatum)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.