Plants 4-8 dm, pubescent throughout; stipules persistent, foliaceous, lanceolate, those of the lower lvs to 4 cm, the upper gradually reduced; petioles 2-5 mm; lfls oblanceolate, the larger ones to 8 cm; raceme usually solitary, ±declined, 1-2 dm, secund; bracts persistent, lanceolate or oblong, 1-3 cm, reticulately veined; pedicels 1.5-4 cm; fls pale yellow to nearly white, 20-28 mm; pods ellipsoid, 3-5 cm, pubescent, tapering to a conspicuous beak. Prairies and open upland woods; s. Mich. to se. Minn. and w. Neb., s. to Miss. and Tex.; e. Ala. to S.C. and w. N.C. May, June. our plants are var. glabrescens (Larisey) Isely. (B. leucophaea) The more southeastern var. bracteata has longer petioles, commonly 4-10 mm.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.