Herbage, especially the lvs, densely villous-sericeous at first with long, lax but not strongly spreading hairs, later more thinly hairy or partly glabrous; lfls 15-31, lance-linear to lance-ovate, 5-25 mm; spikes dense, 2-4 cm, much longer in fr; fls purple, 1.5-2 cm; fr lance-ovoid, rather chartaceous, not rigid, sparsely or moderately pubescent with loose or subappressed hairs, 1.5-2.5 cm, including the beak; 2n=32, 48. Rocks, cliffs, and gravelly shores; circumboreal, in Amer. s. to N.S., Me., Wis., Colo., and Oreg. July. The foregoing description is based primarily on var. johannensis Fernald, which occurs in N.S., n. Me., and s. of the St. Lawrence R. in Que. Var. chartacea (Fassett) Barneby, from n. Wis., tends to have slightly looser and more persistent pubescence, and has smaller pods only 8-15 mm. (O. chartacea)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.