A perennial, herbaceous legume that reproduces by seeds and spreads vegetatively. It can form large clumps from creeping stems. The stems can be up to 6 feet long. Rhizomes can be up to 10 feet long, enabling the plant to spread rapidly. The compound leaves have 15-25 pairs of oblong leaflets. Native vetch species have vining tendrils at the ends of the stems, but crown vetch does not have any tendrils. Blooms May through August. Flowers are pinkish to white and are clustered in umbels (circular, like a crown) on long stalks. Each individual flower is shaped like typical a pea flower. The fruits are narrow, flattened pods.