Biancaea decapetala (Roth) O.Deg.

Climbing or straggling bushy shrub up to 8 m high, often forming dense impenetrable thickets. Stems ± densely clothed with short brownish pubescence or puberulence when young, rarely sparsely clothed or subglabrous, armed with scattered ± straight spreading prickles 1-8 mm long. Leaves finely fulvous-pubescent: petiole 3-6.5 cm long, eglandular, armed on the lower surface with hooked prickles; rhachis (8)12-35(40) cm long, armed on the lower surface with downwardly hooked prickles up to 6 mm long, often in pairs especially at the insertions of the pinnae, and on the upper side usually with solitary upwardly curved prickles at the insertions of the pinnae; pinnae 4-11 pairs; rhachillae 2.5-9 cm long, usually unarmed; leaflets 8-13 pairs per pinna, (0.8)1-2.1 cm long, 0.3-0.8 cm wide (in our area), ± oblong to slightly obovate-oblong, ± rounded apically and often minutely mucronate, shortly petiolulate, pubescent or puberulous on both surfaces, especially on the midrib below. Stipules asymmetrically ovate, acuminate, 4-20 mm long, 2-8 mm wide, margins undulate. Racemes 10-40 cm long, axillary and terminal, simple, sparsely prickly; bracts up to 11x4 mm, lanceolate to ovate-triangular, margins undulate, deciduous before the flowers open. Flowers pale yellow; pedicels 1.5-3.5 cm long, sparsely to ± densely fulvous-pubescent, ascending at an acute angle from the main axis. Sepals 8-11 mm long, appressed fulvous-to greyish-pubescent outside. Petals 10-15 mm long, 8-15 mm wide (the upper one smaller, 8-11 mm long, 5-6 mm wide). Stamens (9)12-20 mm long; filaments densely villous basally, glabrous above. Ovary pubescent. Pods brown, 6-9.5 cm long (excluding beak), 2-2.7 cm wide (in our area), straight or slightly curved, compressed, unarmed, shortly pubescent when young but ± glabrous at maturity, ultimately dehiscing along the upper suture, with a slender beak 0.6-3 cm long arising at the apex near the line of the upper suture; the exocarp sometimes flaking off in old pods to reveal the pronounced reticulate venation of the endocarp. Seeds 8-10 mm long, 6-8 mm wide, ellipsoid, mottled brown and blackish or uniform brown.

Hedges and open bushy places. Swampy localities and ravines; at elevations up to 1,800 metres. Open grasslands, scrubland and forest fringes; at elevations from 1,000-1,700 metres.

Cultivated as an ornamental and hedge plant (e.g. thorny habit acts as a livestock barrier). Traditional medicinal uses. Source of tannin (bark). Oil from seeds used as a lubricant and for soap. Insecticide made from seeds and roots. See Fern (2014) and references therein. Tannin from the seeds is used in the tanning industry (C.S. Boonkerd, Prosea Handbook 3: 57, 1991).

Can be grown by cuttings or seedlings. Seeds needs soaking.