Several-stemmed perennial from a woody root, 3-12 dm, hairy throughout; lower lvs reduced and deciduous, the others rather numerous and uniform, sessile, lanceolate or rather narrowly ovate; cor 8-16 mm, the dull white or greenish white lobes acute, 11/2-2 times as long as wide. Open, moderately dry places; N.Y. and s. Ont. to Va., Tenn., and La., w. to Alta. and N.M. June, July. Three vars. in our range.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.