Cal-tube obconic; cal-lobes half-orbicular to lanceolate, equal or the lowest one slightly larger, standard obovate or broad cuneate, ±folded about the base of the stamens; wings and keel none; stamens 10, exsert; filaments united only near the base; ovary short, 2-ovuled; fr oblong, often curved, slightly compressed, indehiscent, 1-2-seeded; shrubs with pinnately compound lvs, numerous penninerved lfls, and small anthocyanic (white) fls in dense spike-like racemes from the upper axils and terminal. 15, N. Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.