Perennial herb, up to 400 mm high; branches many, from woody rootstock. Leaves pinnate; leaflets linear-oblong or sublanceolate. Flowers: in many-flowered racemes on long, slender peduncles; peduncles much longer than leaves; stems bearing 1-5 racemes each; calyx lobes 1.0-1.5 mm long; standard with brown hairs on back; corolla 8-10 mm long, crimson-red; Aug.-Dec. Pods cylindrical.