B. decapetala is as a robust, thorny, evergreen shrub 2–4 m (6.6–13.1 ft) high or climber up to 10 m (33 ft) or higher; often forming dense thickets; the stems are covered with minute golden hair; the stem thorns are straight to hooked, numerous, and not in regular rows or confined to nodes. The leaves are dark green, paler beneath, not glossy, up to 300 mm (12 in) long; leaflets up to 8 mm (0.31 in) wide. The flowers are pale yellow, in elongated, erect clusters 100–400 mm (3.9–16 in) long. Fruit are brown, woody pods, flattened, unsegmented, smooth, sharply beaked at apex, about 80 mm (3.1 in) long.
Invasive in South Africa, Kenya, and Hawaii.
