A low, deciduous shrub about 2 ft high; stems branching, and having little or no down. Leaves pinnate, 2 to 4 in. long, with eight to thirteen pairs of leaflets and an odd one; leaflets 1⁄8 to 3⁄8 in. long, oval or obovate, nearly glabrous. Flowers purple, fragrant, very closely set in cylindrical terminal racemes 1 to 2 in. long. Pod one-seeded, 1⁄5 in. long, glandular.
Native of eastern and central N. America; introduced in 1811. Although somewhat similar to A. canescens in foliage, it is really very distinct. It is a true shrub, and has little or none of the grey down so conspicuous in A. canescens; its flower-spikes are also much shorter and not clustered. A rather dainty plant, but scarcely known in gardens nowadays.