Acacia auriculiformis A.Cunn. ex Benth. (as ‘auriculaeformis’), London J. Bot . 1: 377 (1842)
Northern Black Wattle , Ear-pod Wattle
Glabrous tree to 30 m high. Bark fissured, grey to black. Branchlets flattened towards apices, glabrous. Phyllodes linear to very narrowly elliptic, falcate, (8–) 10–20 (–22.5) cm long, (10–) 12–30 (–52) mm wide, with 3 conspicuous, pale, longitudinal veins confluent with or near lower margin at base, the minor veins 3–5 per mm, anastomosing; gland 1, basal, to 3 mm above pulvinus. Spikes 5–8.5 cm long, interrupted, yellow. Flowers 5-merous; calyx 0.9–1.3 mm long, dissected for 1/4–1/3, glabrous; corolla 1.7–2.4 mm long, cut for c. 1/2, glabrous; ovary densely pubescent. Pods very narrowly elliptic to elliptic, flat, 3.2–16 cm long, woody, distinctly undulate, glaucous, glabrous, transversely veined. Seeds transverse, elliptic to broadly elliptic, flattened, 3.6–5.6 mm long, dark brown to black; pleurogram dark; areole open; funicle encircling seed.
Occurs on Cape York Penin., Qld, N of 17S, and in the N.T. N of 14S; also recorded from New Guinea and the Kei Is., fide L.Pedley, Contrib. Queensland Herb . 18: 17 (1975), and parts of Indonesia between 11S and 17S. Grows in well-drained sandy or loamy sand soils, beside watercourses and swamps, in closed or low open forests. Flowers Feb.–Aug.
Often difficult to distinguish from A. polystachya in the absence of pods: apart from differences in spike colour (light golden in A. auriculiformis , +/- white to pale yellow in A. polystachya ) they differ in details phyllode nervature, in A. polystachya the most prominent nerves of the phyllodes run together and often join some distance above the base whereas in A. auriculiformis these nerves remain separated from one another. Acacia auriculiformis is sometimes superficially similar to A. aulacocarpa and related species in general phyllode and pod morphology but is readily distinguished in having widely spaced, anastomosing phyllode nerves and a bright yellow funicle which encircles the seed.
A putative hybrid between A. lamprocarpa and A. auriculiformis occurs at Holmes Jungle, N.T. A hybrid between A. auriculiformis and A. mangium is used commercially in SE Asia for pulp and paper production and for saw logs.
Details of ecology, utilisation, etc. of A. auriculiformis are given in J.W.Turnbull (ed.), Multipurpose Austral. Trees & Shrubs 108 (1986).
Type of accepted name
South Goulburn Is., Voyage of ‘Bathurst’, A.Cunningham ; holo: K n.v ., fide L.Pedley, Contr. Queensland Herb . 18: 17 (1975).
Racosperma auriculiforme (A.Cunn. ex Benth.) Pedley, Bot. J. Linn. Soc . 92: 247 (1986). Type: as for accepted name.
F. von Mueller, Iconogr. Austral. Acacia dec. 9 [pl. 10] (1888); D.J.Boland et al ., Forest Trees Australia 4th edn, 157 (1984); J.Brock, Top End Native Pl . 57 (1988).
N.T.: Bathurst Is. township, I.V.Newman 870 (MEL, NSW); Fogg Dam area, M.D.Tindale 6097 & C.Dunlop (CANB, K, NSW). Qld: Cabbage Tree Ck, R.Coveny 7035 & P.Hind (A, AD, BRI, CANB, E, K, L, MEL, NSW, NU, QRS, UC, US); Wenlock R., at Moreton Telegraph office, Cape York Penin., 7 Oct. 1973, J.T.Waterhouse (NSW, UNSW).