Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Genus Description - Resembling Pediomelum, but the cal flaring back and tearing along a lateral sinus in fr; fr indehiscent, densely glandular, rotund to ovate or shortly elliptic in profile; x=11. (Often included in Psoralea) 3, N. Amer.