A shrub or small tree from 7 to 9 m high, having feathery leave.

Stems
Whitish and pubescent when young becoming darker with age; woody; to 7 m long, branching almost from the base.

Leaves
Bipinnate, consisting of 3 to 10 pairs of primary leaf segments 3.5 to 4 cm long, each bearing 10-to 25 pairs of linear-oblong leaflets 3 to 6 mm long, 0.5 to 1.5 mm wide; a petiolar gland occurs between the 2 pairs of segments closest to the stem; a pair of stout stipular spines, 5 to 50 mm long, occurs at the base of each leaf on younger stems but may be absent on older stems.

Flowers
Bright yellow, numerous, in fluffy globular heads 1.2 cm diameter, usually in clusters of 2 to 6, on individual pubescent axillary stalks 1.5 to 2 cm long, each stalk with pair of bracts nearits mid-point.

Fruit
Gray-green, softly hairy flattened pod 6 to 25 cm long, 1 to1.5 cm wide, strongly constricted between each seed; pods slightly sticky internally.

Seed
Depressed, subglobular.

Root
A deep woody taproot with several branching surface laterals.