Tree up to c. 10 m. tall, trunk up to 6 dm. diam. (juveniles of densely divaricating form). Branches spreading or drooping, young branchlets clad in pale to fulvellous tomentum. Lvs up to 15 cm. long or more, with 20-40 pairs of lflts. Lflts 5-7 mm. long, rarely up to 1 cm., obovate-oblong, clad above and below in appressed silky hairs, us. becoming glab. on both surfaces when mature, midrib distinct below. Fls up to 4·5 cm. long, in 4-10-fld racemes, pale to golden yellow. Calyx silky-tomentose, 1 cm. or more long; standard up to 3 cm. long, wings = or a little > standard; keel c. 4 cm. long. Pods fulvellous-tomentose when young, broadly winged, up to 15 cm. or more long, 6- or more-seeded. Seeds brownish to golden yellow, 5-8 mm. long.

2n = 18

2n = 18

Moderate to large tree up to 25 m high, with 1 main trunk or several prominent main branches; branches weeping, spreading and ascending. Divaricating and/or strongly flexuose juvenile branchlets present; branchlets often strongly interlaced, yellow-brown to orange-brown, glabrous to sparsely pubescent, becoming increasingly pubescent during the transition to adult branchlets; hairs appressed, straight. Seedlings and juveniles sparsely to moderately leafy, leaves with increasing numbers of leaflets. Leaflets on juveniles 3.0-5.8 × 2.3-4.9 mm, broadly obovate to orbicular, ± glabrous to sparsely pubescent, distant, not crowded or overlapping. Leaves on adults up to 15 cm long, imparipinnate, petioles and rachides channelled above, leaflets 30-50. Leaflets on adults 4.5-12.5 × 2.3-5.7 mm, elliptic, broadly elliptic, obovate to ovate, sometimes ± orbicular, distal and proximal leaflets usually similar in size, not crowded or overlapping, distant, adaxial and abaxial surfaces ± planar, adaxial surface light green to green, abaxial surface light green; apices retuse to rounded; bases cuneate to obtuse; petiolules 0.4-1.1 mm long, distinct; petioles, rachides, petiolules, and leaflets sparsely to moderately pubescent, hairs 0.2-1.0 mm long, appressed, straight. Inflorescences racemose, withup to 7 flowers; peduncle and rachis 10-25 mm long; pedicels up to 16 mm long, each subtended by a bract; bracts 1.8-3.4 mm long; peduncles, rachides, pedicels, bracts, and calyces moderately to densely pubescent, hairs brown to yellow-brown, usually appressed but sometimes weakly spreading. Calyx 5-11 × 7-10 mm, cupulate, rim shallowly lobed, with deeper notch adjacent to standard. Corolla yellow; keel petal blade 18-50 × 7-13 mm, wing petal blade 18-50 × 6-11 mm, standard petal blade 20-35 × 14-25 mm; petals with distinct claws, 4.0-8.0 mm long. Stipe 7-10 mm long, glabrous to moderately pubescent. Ovary 8-17 mm long, densely pubescent; hairs up to 0.5 mm long, off- white to light brown, appressed to spreading, straight. Style 10- 15 mm long, glabrous to sparsely pubescent. Stigma glabrous or fringed with few short hairs. Filaments 20-35 mm long. Anthers 2.0-2.5 × 1.0-1.3 mm. Fruit 50-200 mm long, 4-winged, brown, sparsely to moderately pubescent, with up to 12 seeds. Seeds 5.5-8.5 × 4.0-5.5 mm, oblong, elliptic to ± orbicular, yellow to light yellow-brown. FL (May-)Aug-Oct; FT Oct-May.