The Pacific states, and small areas of Idaho and Nevada
Mountainous, moist or wet locations, 5,000 to 10,000 feet
Divided into between 5 and 17 leaflets, the largest up to 5.5 inches long
Lupinus polyphyllus inhabits moist, mountainous areas of the westernmost states. Plants grow relatively tall, and have larger-than average leaves, quite variable in the number of leaflets, between 5 and 17. All plant parts are hairless or only very lightly hairy. Leaves grow around the base and along the stems, on stalks up to two inches long. The inflorescence occupies the upper 2 to 15 inches of the stems.
Flowers are often whorled, attached by green, bracted pedicels around half an inch long. Flowers are also around half an inch in length. Petals are colored various shades of blue and purple, and white, and the banner spot is white to pale yellow.
Var pallidipes has leaflets which are lightly hairy on the upper surface, var burkei has hairless leaflets numbering 5 to 11, while var polyphyllus has hairless leaflets numbering 9 to 17.