Acacia Mill.

Armed or unarmed trees or shrubs. Leaves alternate or fasciculate from spurs or both, bipinnate or reduced to simple phyllodia;  leafstalk glands usually present, sessile or occasionally stalked, circular or elliptic; pinnae one to numerous pairs; leaflets usually

numerous; stipules spinescent or small and deciduous. Inflorescence(s) yellow or whitish yellow heads or spikes that are pedunculate and either fasiculate, occasionally solitary, or congested in axillary racemes. Calyx usually shallowly lobed; corolla lobed a third to half of length; androecium of numerous free stamens. Legume sessile or stipitate, promptly or tardily dehescent or indehiscent, usually oblong to linear, flat to turgid, straight or curved, with thin or thick valves. Seeds few to several. Warm regions and tropics of major land masses except Europe, 1000 to 1200 species. (ISE)

1. Mature leaves bipinnate…2

1. Mature leaves phyllodes (broadened petioles resembling leaf blades)…3

2. Leaflets 4-8 pairs…A. choriophylla

2. Leaflets more than 9 pairs…A. farnesiana (If the leaflets are wider than 2 mm and the pods are constricted between the seeds, consider Acacia nilotica.)

3. Phyllodes pubescent, bluish green…A. podalyriifolia

3. Phyllodes glabrous…A. pycnantha

(WU1, ISE, PBCC)