Acacia polystachya A.Cunn. ex Benth.

Tree 3–25 m high. Bark smooth to corrugated or coarsely plaited, grey or dark brown. Branchlets angular or ± flattened, grey, brown or purplish, smooth or pustulate. Phyllodes very narrowly elliptic to narrowly elliptic, sometimes asymmetrical, ± straight to falcate, 7.5–25 cm long, 10–32 mm wide, ± chartaceous, glabrous, with 2 or 3 (rarely 4) prominent veins which run together and often join some distance above phyllode base and remain separate from lower margin; minor veins 5–9 per mm, sparingly anastomosing; gland 1, basal, to 3 mm above pulvinus. Spikes 3.5–7.5 cm long, loosely arranged, pale yellow. Flowers 5-merous; calyx 0.4–0.7 mm long, dissected to ½, glabrous; corolla 1.6–1.8 mm long, dissected to ½, glabrous; ovary densely pubescent. Pods linear, ± straight-sided to slightly and often irregularly more deeply constricted between seeds, curved to strongly curved and irregularly twisted, 8.5–13 cm long, 6–10 mm wide, thinly coriaceous, blackish, often pruinose, glabrous. Seeds longitudinal, ± discoid, 3.5–4.2 mm long, black, minutely pitted; pleurogram without halo; areole elongate, open; funicle encircling seed, yellow.

Alluvial soils often near watercourses in semideciduous mesophyll vine thicket and deciduous vine thicket or along beaches by the coast; at elevations up to 500 metres.

Details of ecology, utilisation etc. are given in J.W. Turnbull (ed.), Multipurpose Australian Trees & Shrubs 186 (1986).

Can be grown by seedlings. Seeds needs soaking.