Rather coarse-rooted perennial from a stout caudex, the stems tufted, 2-6 dm, simple to the infl; lvs alternate or opposite, Ā±elliptic, narrowed to the base, flat, 3-8 × 1.5-3.5 cm, entire or often coarsely few-toothed, sometimes glaucous, not much reduced upwards; infl broadly rounded, much-branched, not secund, 4-10 cm wide, the branchlets narrowly winged; fls mostly 5-merous; sep ca 2.5 mm; pet white to light pink, 4.5-6 mm; nectaries white or pale yellow, ca 1.4 times as long as wide; ovaries white, pale green, or pink; frs short-stipitate, erect with divergent beaks; 2n=24, seldom 48. Dry, rocky places in the mts. from s. Pa. to N.C.; disjunct in s. Ind. and Ill. and w. Ky., and rarely escaped elsewhere. Aug.-Oct.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.