Probably frequent to very rare throughout the state except in the extreme northern counties. It is found mostly along roadsides and in alluvial bottoms of streams. It is essentially a prairie plant but is occasionally found in wooded areas and it is a question whether it exists in some places as a relict or is an invader.
Rhizomatous perennial, simple or sparingly branched, erect, to 1.5 m; lfls bright green, lanceolate or lance-ovate, 5-10 cm, half as wide, acuminate, thinly pubescent beneath; stipules and bracts subulate; peduncles nearly equaling the subtending lvs; racemes 3-8 cm; fls blue, varying to white, 6-7 mm; cal minutely pubescent to glabrate, 2-3 mm, slightly oblique, the short, broad lobes subequal; fr ovate, acuminate, 8-10 mm. Open woods and moist prairies; O. and Ky. to Io. and Mo.; also mt. woods, w. Va. to e. Tenn. and w. S.C. June, July. (Psoralea o.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.