Silver Stem Lupine
Lupinus argenteus Pursh

Probably collected near Kamiah in Idaho Co., Idaho, on 5 Jun 1806. (Source)

Silvery lupine is a perennial from twelve to thirty inches tall. Has howy terminal and dense racemes 1-2' long, individual flowers butterfly-shaped, blue to  lilac or lavender, forming in narrow, curved clusters up to eight inches long. Inch-long pods (legumes) containing dark yellow seeds develop later. Older plants usually have several stems from a heavy taproot. Dense hairs on stems and leaves give the plant a silvery appearance. Leaves are about two inches long, the tips divided into six to eight narrow leaflets that radiate like fingers from a hand. Above the leaves, blue flowers blooming in late summer.  Adapts to wide range of soils but prefers low fertility, dry habitats with sun to part shade. Found in  meadows, openings, foothills, montane, subalpine, and elevation ranges from 1,510 to 3,330 feet. 

Caution:  Plant parts are poisonous, especially to livestock. contain poisonous alkaloids,.  Lupine poisoning may cause dizziness' and incoordiation, slow breathing and heart rate.