Many-stemmed shrub to 4 m. Stems branched, pubescent. Leaves often fascicled, becoming glabrate, even-pinnate with 4 to 10 oblong-elliptic leaflets 1–3 cm long with rounded or truncate, mucronate tips; stipules often with nodal spines. Inflorescence of 1 to 4 flowers, fascicled on spur branches. Flowers papilionaceous, yellow; calyx pubescent, 6–7 mm long; sepals ca. 1 mm long; banner ca. 2 cm long, reflexed, barely longer than the wings and keel. Fruit a glabrous, pendent, linear-oblong legume, 3–5 cm long, narrowed to a slender beak; seeds numerous (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
POLLINATORS The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap:
Bombus centralis,
Bombus fervidus,
Bombus huntii,
Bombus griseocollis, and
Bombus impatiens (Plath 1934, Thorp et al. 1983, Colla and Dumesh 2010).