A spreading, sprawling annual with 4-sided stems that are rarely upright. Flowers arise on long stems from leaf axils, white, with 4 petals; in small groups, each group subtended by a few bracts. Blooms May–July. Leaves in whorls of 6–8, usually about 2 inches long, linear to oblanceolate. All green parts are covered by small, coarse, recurved hairs that cling to animals and clothing. Fruits are round, about ¼ inch across, with bristles, green at first, turning tan. The fruit matures by early summer, and the entire plant dries up. The plants aren't seen until the seeds germinate the next spring.
Similar species: There are 15 species of Galium recorded for Missouri. Some species sprawl on the ground or on nearby vegetation, while others are more erect. Some are native to America and others are introduced. Most have 4 or more leaves per node. The fruits form in pairs, like two tiny balls side by side.