Description from Flora of China
Subshrubs or perennial herbs, small, 20-50 cm tall, sometimes to 1 m. Stems branched at base; branchlets purple, thin, adpressed white pubescent. Leaves 3-foliolate; petiole 1-2 cm, adpressed white hairy; leaflets elliptic, oblong, or ovate-oblong, terminal one (0.6-)1-3.5 × 0.4-1.5 cm, abaxially densely adpressed pubescent, adaxially glabrous, base rounded, apex rounded or obtuse-rounded, sometimes emarginate, mucronate. Racemes axillary, laxly flowered, often 3-flowered; peduncle thin, filiform or stouter, distinctly overtopping leaves, adpressed white or spreading hairy. Pedicel short. Calyx 4-7 mm. Standard white, with purple spots at base, ca. 6 mm; wings shorter; keel longer than standard or subequal. Cleistogamous flowers clustered in leaf axils, sessile, fruit-bearing. Legume nearly orbicular, often not overtopping calyx.
Rocky mountain slopes, mountain forests, roadsides, thickets; below 800 m. Anhui, Fujian, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Shaanxi, Shandong, Shanxi, Taiwan, Zhejiang [Japan, Korea].