Lupine (Latin lupus, "wolf," from the belief that it robs the soil), is the common name for several annual or perennial herbaceous plant species in the pea family (Leguminosae or Fabaceae; see legume) genus Lupinus. Lupines are characterized by palmately compound leaves (ie, leaflets that radiate from a central point) and showy flower spikes. These traits make lupines admirable ornamentals (eg, "Russell Hybrid" lupines).
Worldwide, there are about 200 to 500 lupine species, with 2 principal areas of distribution: the western mountains of North and South America (90% of the species) and the Mediterranean basin (10% of the species). In Canada, about 28 species are recognized. Most occur in Western Canada from southern Saskatchewan to British Columbia; L. arcticus and L. nootkatensis reach the western Arctic; L. perennis occurs in southern Ontario; and the western species, L. polyphyllus, is naturalized in Eastern Canada. Some cultivated lupines have escaped and are now naturalized along roadsides. Some species are grown for fodder and green manure. In Canada, lupines are used as a cover crop in reforestation projects. Lupines enrich nitrogen-poor soils.
Compounds called quinolizidine alkaloids make seeds from most lupine species poisonous to livestock, although vegetative parts of the plants are not. Poisonous lupine seeds can be treated by leeching to remove the toxic compounds, after which they can provide a protein source for livestock. Not all lupines are poisonous, and some are cultivated by humans for food. For example, the Balkan species, L. albus, is cultivated in Europe and South Africa for its edible seed.
See also Poisonous plants.