Northern Prairie Wildlife Research Center
Few wildflowers are more characteristic of the western mountains and grasslands than the lupines. Only a single native species inhabits eastern North America, but at least 70 species occur in the west. Nearly all North Dakota collections of small lupine have been from west of the Missouri River. Overall range of the plant is from southern Saskatchewan and Alberta south to Oklahoma and New Mexico at elevations up to 8,000 ft.
Also called "rusty" lupine, small lupine is an annual with a taproot. Stems are up to 8 inches tall, simple or much branched, and densely covered with pale brown hairs. The alternate leaves are up to 6 inches long. Each leaf has a 2-inch stalk (petiole) and 6-8 leaflets about an inch long arranged palmately (like fingers on a hand). Flowers are about 1/2 inch long and form dense clusters of 10-20. Colors range from white or yellowish-white to (usually) pale blue. Mature legumes (seedpods) are up to an inch long, covered with tan hairs, and contain two large, pale seeds.
Look for small lupine from June through August on native prairie, especially where soils are sandy. The plant is reportedly poisonous to livestock, but documented cases are rare or absent. Nevertheless, lupines, especially the seeds, are known to contain dozens of notoriously toxic alkaloids. Many lupines are beneficial, however, and have been used in Europe and the Middle East for human foods and drinks, for livestock forage and green manure, and to rehabilitate worn-out soils.
Lupines are members of the extremely economically important bean family (Fabaceae). Fab means "bean" in Latin. The generic name Lupinus is an ancient name for these plants taken from lupus, "wolf," because of an old belief that the plants destroy the soul. The specific epithet pusillus means "very small" in botanical Latin. Small lupine was first described for science in 1814 by the famous German-born Philadelphia botanist Frederick Traugott Pursh (1774-1820). Pursh catalogued and described many of the new plant species brought back from the western wilderness by Lewis and Clark.