228 LEGUMINOSAE (PULSE FAMILY) 
In Europe, where stall-feeding of farm animals is more commonly 
practiced than in this country, it has been found that Lupine 
fodder is rendered entirely innocuous by steam heating under 
pressure, which at the same time makes it much more palatable 
and fattening. Dry heat does not destroy the poison. In many 
places it would be advisable to put the ground under cultivation 
with the purpose of replacing these plants by some less dangerous 
member of the Legume Family. 
SILVERY LUPINE 
Lupinus argénteus, Pursh. 
Other English names: Blue Pea, Blue Bean. 
Native. Perennial. Propagates by seeds. 
Time of bloom: July to August. 
Seed-time: August to September. 
Range: Nebraska and the Dakotas to the plains of the Columbia 
River, southward to New Mexico and Arizona. 
Habitat: Prairies, hillside slopes; wild pastures and meadows. 
On the sides of the vast foothills of the Rocky Mountains this 
and other species of Lupines often completely cover the ground for 
miles, and when in bloom the wide tracts of blue flowers are visible 
at a great distance. If the plant is to be used for hay it should 
be harvested while in bloom, or else very late, after the seeds 
have ripened and been cast from the pods. The leaves remain 
succulent until frost. 
This is a very variable species but is usually a somewhat shrubby, 
bushy-branched plant, one to nearly three feet in height, densely 
covered with fine, silky, appressed hairs. Leaves on slender 
petioles about as long as the blades, the leaflets five to eight, nearly 
smooth above but silvery-hairy beneath, linear to lance-shaped and 
pointed at both ends. Racemes terminal, usually densely flowered, 
two to five inches long; calyx-lips unequal, the upper one rather 
broad, two-toothed, the lower one longer and entire; petals usually 
purple but sometimes pale blue or cream-colored, the standard and 
keel sometimes finely hairy. Pods about an inch long, silky-haired, 
three- to five-seeded. 
Means of control should be similar to that of the Nebraska Lupine. 
