Stout, glabrous perennial 3-6 dm; cauline lvs 5-10 pairs, lanceolate to oblanceolate, mostly 6-10 נ1-2 cm, acute or acuminate, the basal ones wider; infl a many-fld head with narrow, leafy bracts; cal glabrous, 15-18 mm, ca 40-nerved; pet-blade whitish to dark red, 5-10 mm, broad, toothed around the broad summit; fr 1 cm; 2n=30. Native of Eurasia, occasionally escaped from cult. especially in the n. part of our range. June-Aug.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.