Crown vetch, a member of the pea family, is a perennial herb with creeping stems that may reach two to six feet in length. The compound leaves bear 15 to 25 leaflets. The pealike, pink to white flowers occur in clusters at the end of extended stalks. The narrow, leathery seed pods may be 2 to 3 inches long. The following three characteristics together distinguish crown vetch from other legumes: 1) its compound leaves have an odd number of leaflets, 2) the leaves and flower stalks arise from the main stem, and 3) the flowers occur in a radiating cluster known as an umbell.