牛蹄豆 niu ti dou

Mimosa dulcis Roxburgh, Pl. Coromandel 1: 67. 1798.

Trees, evergreen. Branches often pendulous; branchlets armed with spinescent stipules. Pinnae 1 pair; glands at junction of pinnae and leaflets; leaflets sessile, 1 pair per pinna, elliptic or obovate-elliptic, 2-5 × 0.2-2.5 cm, both surfaces glabrous, reticulate veins raised abaxially, base slightly oblique, apex obtuse or emarginate. Inflorescence pedunculate heads, aggre­gated in terminal panicles. Calyx funnel-shaped, 1-1.5 mm, to­mentose. Corolla ca. 6 mm. Stamens numerous, connate into a tube at base. Legume blackish brown, curved into a circle, flat, 5-7 cm in diam. Seeds dark brown, shiny, ovoid-ellipsoid, ca. 1.5 cm, hard, with pleurogram. Fl. Mar-Jun, fr. Jul. 2n = 26.

Cultivated in Fujian, Guangdong, Guangxi, Hainan, Jiangxi, Tai­wan, Yunnan, Zhejiang [native to tropical regions of C and N South America; cultivated throughout the tropics].

The timber is used for general construction and the bark for its tannins.