Erect, spreading or contorted tree or shrub, 1–10 m high; young stems commonly hispid. Phyllodes crowded, linear, lanceolate or subulate, 1–4 cm long, 1.5–4 mm wide, very stiff and sharply pungent, sessile, mostly glabrous; veins 3–5 with the upper one becoming marginal towards apex of phyllode; gland absent; stipules prominent, rigid. Spikes dense, 1.5–5 cm long, commonly exceeding phyllodes, pale to bright yellow; rachis hairy; peduncles 3–12 mm long. Flowers 4-merous; sepals united, pubescent. Pods cylindric or slightly compressed, 6–11 cm long, 4–8 mm wide, longitudinally wrinkled, woody; seeds elliptic, 3.5–5 mm long, funicle short, thick, folded 2 or 3 times, aril turbinate. Flowers Jun.–Nov.
LoM, Wim, GleP, Brid, VVP, VRiv, GipP, OtP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, WPro, HSF, HNF, OtR, Strz. Also SA, NSW. Widespread in dry heathlands, woodlands and forests in the southern half of Victoria, usually on sandy soils.
Acacia oxycedrus hybridizes readily with several closely related species. Putative hybrids with A. longifolia subsp. sophorae have been recorded from between Nelson and Kentbruck in far south-western Victoria, from Western Port and from Sperm Whale Head, south of Bairnsdale. Acacia longifolia subsp. longifolia is thought also to hybridize with A. oxycedrus and material derived from these supposed parents has been recorded from the south-eastern suburbs of Melbourne (e.g. Hampton), the Grampians and possibly near Wangaratta. Hybrids between A. oxycedrus and A. mucronata subsp. longifolia were described as A. mucronata var. acuta by Williamson (in Ewart 1931). The name was based on specimens gathered near Halls Gap in the Grampians and near Warburton in central Victoria. Similar material has also been recorded from the Plenty Ranges, Cockatoo, Mt Observation and Bemm River. In New South Wales, A. floribunda-A. oxycedrus hybrids have been reported. All of these presumed hybrids can be distinguished easily from A. oxycedrus by the length of their phyllodes which exceed 4.5 cm and from their other parent by their phyllodes gradually tapering into hard sharp and rigid points and often by the presence of obvious and persistent stipules.
