Plant of the Week
Range map of Goat's Rue, Tephrosia virginiana.
Goat's Rue, Tephrosia virginiana. Photo by Thomas G. Barnes, USDA-NRCS PLANTS Database.
Goat's Rue (Tephrosia virginiana L.)
By Larry Stritch
Goat’s rue is a beautiful native plant that flowers from May to August and prefers rocky open woods, glades and prairies. Found in the Eastern portion of the United States, this plant has large roots that fix nitrogen. Plants grow 1-3 inches tall with pink and white, or pink and pale yellow, flowers bunched at the top. They cannot grow in shade and prefer sandy soils.
Due to the special relationship this plant has with the acidic soils it grows in, many have found this plant difficult to propagate.
The Genus Tephrosia originated from the Greek word tephros meaning "ash-colored" or "hoary".
Traditionally the plant was used to treat ailments such as tuberculosis, rheumatism and bladder problems. The plant is also being studied in cancer research. The seeds are reported to cause nausea and Seminole Indians are said to have used the root, which contains the insecticide rotenone, to poison fish. Other folklore speaks of pouring a tea made from the roots on garden plants to kill insects. Long, thin and tough, the roots are the source of the name "devil's shoestring." The long roots also make this plant drought resistant. This native plant's stems are covered with a silky, silver hair that has caused allergic reactions in some people.
At one time this plant was fed to goats as it was thought to improve milk production. That earned it the common name "goat's rue" due to the presence of rotenone. That practice is no longer followed.