Description from Flora of China
Robinia ferruginea Roxburgh, Fl. Ind., ed. 1832, 3: 329. 1832, not Kunth (1823).
Lianas. Branchlets densely rust-colored pubescent. Leaves 5-9-foliolate; rachis 5.5-9(-15) cm, including petiole 3.5-5(-10) cm; leaflet blades elliptic to obovate-oblong, 6-13 × 2-5 cm, leathery, abaxially slightly rust-colored puberulent, adaxially glabrous and shiny, base rounded, apex obtusely acuminate. Pseudopanicles axillary, 15-30 cm, densely rust-colored puberulent; rachis nodes with 2 or 3(-8) fascicled flowers often borne on a short branchlet. Pedicel slender, 4-6 mm. Flowers 1-1.4 cm. Calyx ca. 3 mm; teeth minute. Corolla pale red to whitish, 8-10 mm. Ovary pubescent. Legume oblong to ligulate-oblong, 5-8 × ca. 2.5 cm, leathery, flat, densely rust-colored sericeous when young, nearly glabrescent when old; abaxial suture with a 2-4 mm wide wing, adaxial suture with a 3-5 mm wide wing. Seeds 1 or 2 per legume. Fl. Apr-Jul, fr. Sep-Dec.
Sparse forests and thickets, low elevation mountain slopes; 500-1200 m. Guangdong, S Guangxi, SW Guizhou, Hainan, S Yunnan [Bangladesh, India, Laos, Myanmar, Thailand, Vietnam].