The silky lupine, lupinus sericeus
, has the palmately-divided leaves typical of this genus, the 6 to 9 segments slightly folded, growing quite densely on brownish, finely hairy stems, the uppermost portions of which bear the inflorescence. Leaves also have a light covering of fine hairs. The stalks of the lowest leaves can be up to three times the length of the leaflets. Flowers grow on short petioles and are greenish-yellow at first, becoming dark pink when mature. The uppermost petal (the banner) is mostly hairless and does not bend strongly backwards as in some similar species. The plant is poisonous, especially to sheep.