Infrequent to frequent throughout the state (with the probable exception of Benton County) in dry, rich soil in black and white oak and beech and sugar maple woods and rarely in a moist habitat. The position of the leaflets on the stem is variable. Generally they are crowded at the summit, and more rarely there are a few smaller ones below the summit. Lunell (Amer. Midland Nat. 2: 128. 1911) described a form with "leaves not clustered at the base of the peduncle, but further down on the stem. In addition to these there is one single leaf at the base of the peduncle, and often one or sometimes two single leaves beneath this. Lastly, there are often one or two single leaves on the stem below the clustered part." He cited a specimen of mine collected in Wells County. This form is now known as Desmodium acuminatum f. Chandonnetii (Lunell) Fassett.
Stem solitary, erect, 1-4 dm, generally bearing near the summit several long-petioled lvs and prolonged into a terminal panicle 3-8 dm; stipules narrow, persistent; lateral lfls asymmetrically obovate, acuminate; terminal lfl round-ovate, 7-15 cm, long- acuminate; fls 6-8 mm, purple (white); pedicels 3-8 mm; stamens monadelphous; cal-lobes short; stipe glabrous, 4-12 mm; articles (1)2-3(4), triangular or semi-obovate, 8-12 mm, glabrous on the upper margin. Rich woods; N.S. to Sask., s. to Fla. and Mex. July. (D. acuminatum; D. grandiflorum, misapplied)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.