The flowers of the plants I have seen are white and odorless and the pods are about 4-seeded. I found it to be a common plant in hard, white, slightly acid, clay soil in a clearing, formerly wooded with swamp white oak and pin oak, along Little Pigeon Creek in Spencer County. I found it in great colonies in a low, flat woods 10 miles southwest of Mt. Vernon in Posey County where it was associated with post oak, agave, and Baptisia leucantha. Other specimens were found in dry woods, on a cliff along White River, and in dry, sandy soil in a prairie habitat in Vigo County. This is the western form of this species. The type came from Augusta, Illinois.
Biennial or winter-annual, forming an overwintering rosette, variously hairy or glabrous, erect or ascending 2-5 dm, the stems branched from the base, not stoloniferous; lvs with progressively shorter petioles upwards; lfls ovate, oval, elliptic, or narrowly obovate, 2-3 cm, much longer than wide, conspicuously serrate, often marked with purple bands; peduncles 2-8 cm; heads globose; fls 8-12 mm, on pedicels to 1 cm; cal-tube 1.2-1.7 mm, the lobes linear, 3-7 mm; standard red or white, broadly elliptic-obovate, exceeding the pink or white obtuse wings; seeds 1.2-1.5 mm; 2n=16. Upland woods and prairies; w. N.Y. and s. Ont. to Io. and Kans., s. to Fla. and Tex. May-July.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.