Ground plum is a many-stemmed, bushy perennial. Flowers in tight racemes, nearly 1 inch long, cream-colored with lilac-blue tips of the keel petals; also purple to bluish purple or pinkish purple or greenish yellow to white. Blooms March–May. Leaves compound, with many opposite, oblanceolate leaflets. Fruit nearly ball-shaped with a central ridge, with a sharp, beaklike point; smooth, about ¾ inch wide.
Similar species: Four species of Astragalus are recorded for Missouri. Rattleweed (A. canadensis) blooms May–August and grows to 4 feet tall. Its long clusters of flowers are greenish white to cream-colored. The compound leaves have many opposite leaflets that get shorter toward the tip and are oblong to elliptical. It grows statewide, usually in open, wet lowlands.
Height: to about 20 inches.
Counties adjacent to and south of the Missouri River. Scattered widely, but apparently absent from the Mississippi Lowlands and uncommon in parts of the Glaciated Plains Division.
Habitat and Conservation
Grows in upland prairies, loess hill prairies, roadsides, embankments, fields, glades, ledges and tops of bluffs, openings of rich to dry upland forests, often on calcareous substrates.
Human Connections
The round, two-parted, cherrylike fruits are succulent and sweet when young and can be eaten raw or boiled. Native Americans and settlers ate them. Because there is a potential for loco poisoning (neurological damage that is not reversible), eating large quantities is not advised.
Ecosystem Connections
Rodents gather, cache, and eat the fruits. Wild mammals tend to avoid eating plants in this genus, since they, like livestock, can be poisoned by the toxic alkaloids present in the plants. The condition is called locoism, for the dazed, frantic, uncoordinated, crazed behavior it causes.
