Low perennial herb to branching shrub from 1 dm. to 1.5 m. high; stem terete to angular, light brown to reddish, striate to grooved, moderately to abundantly strigose with (rarely spreading and/or with only) upwardly directed appressed hairs. Leaves 3-foliolate, the leaflets appearing to be somewhat sensitive; stipules obliquely lanceolate-attenuate, (4–)5–11 mm. long, 1–2 mm. wide, usually densely strigose at the very base and slightly lobed on one side, otherwise glabrous to puberulent, ciliate; petiole abundantly strigose (as is stem), 6–15 mm. long; rhachis similar, 1–5 mm. long; terminal leaflet narrowly obovate, obtuse to rounded at apex and apiculate, cuneate at base, 1–4.8 cm. long, 0.4–1.2 cm. wide, lateral leaflets similar, more nearly elliptic, 1–2.2 cm. long, 0.5–0.9 cm. wide, all glabrous to glabrescent or moderately appressed pilose above, abundantly appressed pilose beneath and with venation prominently reticulate. Inflorescence of lax to rather stiff terminal racemes; rhachides tawny, or brown to red or black, terete to angular, and rather densely upwardly appressed strigose; primary bracts each subtending 2 (rarely 3) pedicels, ovate-attenuate, 3.5–6 mm. long, 1.5–2.5 mm. wide, puberulent and with scattered long tapering hairs, not long persistent; pedicels ascending, black, uncinulate-puberulent and usually densely upwardly strigose (as rhachis), 4–10 mm. long. Flowers pink to mostly reddish or purple (or crimson or purple and whitish). Calyx green to purple, puberulent throughout and often long-pilose on the teeth of both lobes, (2–)2.5–3 mm. long. Standard obovate, retuse at apex, narrowed to an acutish base, 3.5–5 mm. long, 2–4.5 mm. wide; wings ± oblong, slightly narrowed to an obtuse apex, remotely auricled and shortly clawed at base, 2.5–4.5 mm. long, 1.3–2 mm. wide; keel-petals scythe-shaped, long-clawed, equalling standard in length, 1–1.5 mm. wide. Fruits sessile to shortly stipitate, the articles rather prominently reticulate, uncinulate-puberulent and -pubescent throughout, the upper suture somewhat angled above the isthmi, slightly indented above each seed, rounded below and indented at the isthmi, 3–5 mm. long, 2.5–3.5 mm. wide. Seed ± oblong, 2.5–3 mm. long, 1.5–2 mm. wide. Fig. 65/12, p. 453.
