Desmodium is a genus of perennial herbs, stipules present. Plant often hairy.
Leaves alternate, stalked, 3-parted.
Flowers pink to purple, occasionally white, bilaterally symmetrical, bean-flower shaped, 5-parted, upper petal the largest (standard) 2-lobed, rounded to egg-shaped, lateral petals (wings) smaller, two basal petals fused to form the keel that surrounds the 10 stamen, 9 stamens fused around single stigma, 10th, uppermost stamen free.
Fruit dry, covered with hooked hairs, a jointed pod (loment), lower edge notched between seeds and breaking apart at seams between seeds. Dispersed by attachment to fur or clothing (Matlack 1994).
Notes: Ours all native. Some Desmodium species are host to larvae of the orange sulfur butterfly, Colias eurytheme (Pieridae) (Tallamy 2003; Pyle 1981).