Stout, 4-10 dm; lvs numerous, linear or lance- linear, 1-2 dm, scabrellate; umbels 2-10, densely fld (fls often 30-100) on peduncles 1-2(-3) cm; pedicels hirsutulous with spreading hairs; cor pale greenish or slightly purplish, its lobes reflexed, 4-6 mm; hoods 2-2.5 mm, the base separated from the cor by a distinct column, appressed to the gynostegium, obtuse at the summit, reaching just above the base of the anther-wings; horns none. Dry sandy soil and prairies; W.Va., O., and Mich. to Wis., n. Io., Kans., Okla., Ark., and sw. Ky. June-Aug. (Acerates h.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.