Erect perennial 0.5-2 m, glabrous or villous above; stipules subsetaceous; petiolar gland clavate to obovoid, constricted at base into a short stipe; lfls commonly 6-10 pairs, oblong or elliptic, 2-5 cm, acute or obtuse, mucronate; infl of several axillary, many-fld racemes, forming a terminal panicle; buds nodding; sep unequal; pet 10-15 mm, slightly dissimilar; filaments about equaling the anthers; ovary densely villous; pods 7-12 cm x 5-9 mm, tardily dehiscent, sparsely villous, the joints nearly square; seeds nearly as wide as long, flat with a depressed center. Moist open woods, roadsides, and streambanks; Mass. and s. N.H. to s. Wis., s. to N.C., e. Tenn., and Ill. July, Aug. (Cassia h.; C. marilandica and Ditremexa m. of authors, misapplied)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Found infrequently throughout the state although there are no specimens from the southwestern counties. It prefers a moist soil and is found mostly along roadsides and in pastures and open woods in the alluvial bottoms along streams. In many places this species forms large colonies, especially in rather sandy soil in the alluvial bottoms of the Tippecanoe River, and elsewhere in similar habitats. It sometimes invades marshland where it is not too wet and forms complete stands. It is to be noted that grazing animals do not eat this or the next species [Senna marilandica]. I have seen thick stands of this species where the blue grass was closely grazed but this plant was not eaten. The plant contains a strong purgative principle.
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Indiana Coefficient of Conservatism: C = 4
Wetland Indicator Status: FACW
Diagnostic Traits: perennial to 2 m; leaves evenly once-pinnate; petioles with club-shaped gland widest above middle; stamens 3 sterile, 7 fertile; ovules 10-15; legumes 7-12 cm × 5-8 mm, segments nearly square to longer than wide, hairs long-spreading.