Clapp, in his Medicinal Plants of the U. S., published in 1852, on page 79, says: "Two plants have been found growing on the banks of the river at this place, apparently spontaneous." There is a specimen in the herbarium of Wabash College, collected by Dr. Clapp, dated Sept. 14, 1850. There are no other reports. The seed of this species are often used as a substitute for coffee in tropical countries.
Annual (in our range), 3-10 dm, malodorous, bearing in each upper axil a single fl or 2-3 fls in a raceme with a very short common axis; gland depressed or dome-shaped, near the base of the petiole; lfls 3-6 pairs, ovate to elliptic or lance-ovate, 3-8 cm, acuminate; buds nodding; sep unequal; pet 10-15 mm, slightly dissimilar; pods straight or slightly curved, flattened, 7-14 cm נ6-9 mm, tardily dehiscent, glabrous or sparsely hairy, weakly segmented; seeds 4-5 mm, flattened-obovoid with depressed center; 2n=28. Native of the Old World tropics, widely naturalized in the warmer parts of the New World, extending n. to N.C. and Ark., and rarely in our range as an adventive. Late summer. (Cassia o.; Ditremexa o.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.