Also known as Cusick's oxytropis, Cusick's crazyweed is a perennial wildflower with densely silky-hairy, non-glandular stems and leaves. Plants have several to many short stems clustered atop a woody base. The pinnately compound leaves bear 7-17 oblong-lanceolate leaflets with acute tips. The leaflets measure from 4-10 mm long while the leaves are 4-8 cm long, including the fairly long petioles.
The flower stems are 5-12 cm long and topped by a few-flowered, short, dense raceme. The cylindric-bell-shaped calyx is grayish to black-hairy and measures around 8 mm long with the broadly awl-shaped teeth up to one-third as long as the tube. The corolla is yellowish, measuring 10-14 mm long. The banner is 10-12 mm long and deeply notched. The cylindric, non-glandular pods are sessile or nearly so, 15-20 mm long and pubescent with whiteish or black hairs. The pods are narrowly ovate and taper gradually to a pointed beak, which is up to 5 mm long.
variety columbiana: Corollas white, the keel strongly purple-spotted. Leaflets generally number less than 17, but may number up to 23. Found along gravel bars or stony river or lake shores from near the confluence of the Spokane and Columbia Rivers of northeastern Washington north into Canada and east to the Flathead Lake region of western Montana.
variety cusickii: Corollas cream in color (whitish-yellow), the keel not purple-spotted. Leaflets typically number less than 17. Flower stems typically measure less than 15 cm long. Stipules at the base of the leaves glabrous or nearly so. Found east of the Cascade Mts. in Washington east to Alberta and North Dakota and south through the Rocky Mts. to Colorado.
variety gracilis: Corollas cream in color (whitish-yellow), the keel not purple-spotted. Leaflets typically number more than 17. Flower stems typically measure greater than 15 cm long. Stipules at the base of the leaves very hairy. Found from western Washington east to Alberta and North Dakota and south through the Rocky Mts. to Colorado.
variety spicata (O. sericea var. spicata): Corolla lemon to sulphur yellow, the keel typically not purple-spotted. Found north-central or northeastern Washington to northern British Columbia and east to central Idaho and northern Wyoming.
variety wanapum: Corollas pale lavender. Leaflets typically average 22 in number. Plants tend to have longer flower scapes and longer leaves and leaflets than var. columbiana, cusickii, & var. gracilis. Found only on Saddle Mt. in Grant County, central Washington.
Cusick's crazyweed may be found growing in the cracks and crevices of rocky, exposed slopes, on ledges, or on ridgetops between the elevations of 7900-9900' (generally above 2100 meters).
Cusick's crazyweed may be found from the Rocky Mountains of Alberta and British Columbia south (to the east of the Cascade Mts.) across central and eastern Washington to the Wallowa Mts. in northeastern Oregon. It is found eastward across the high country of central Idaho to the Rocky Mts where it is found as far south as northern Colorado.