Acacia implexa Benth., London J. Bot. 1: 368 (1842)
Lightwood , Hickory Wattle , Screw-pod Wattle , Bastard Myall , Lignum Vitae , Fish Wattle , Broad-leaf Wattle
Tree 3–15 m high, often gregarious due to suckering; bipinnate leaves may persist on young plants. Bark rough, greyish. Branchlets terete, not prominently ribbed, commonly lightly pruinose, glabrous. Phyllodes narrowly elliptic, falcate, 7–20 cm long, 6–25 mm wide, much-narrowed at base, acute to acuminate, sometimes obtuse, thinly coriaceous, green, glabrous, with 3–7 main nerves and numerous longitudinally anastomosing minor nerves inbetween. Inflorescences 4–8-headed racemes; raceme axes 10–45 mm long, glabrous; peduncles 6–15 mm long; heads globular, 5–6 mm diam., 30–52-flowered, cream to pale yellow. Flowers 5-merous; sepals 3/4-united. Pods linear, coiled and twisted, to 25 cm long, 4–7 mm wide, woody or thick-coriaceous, glabrous. Seeds longitudinal, oblong-oval, 4–5 mm long, subglossy, dark brown; funicle/aril fleshy, white, folded beneath the seed.
Widespread and sometimes common, occurring in Qld on the Atherton Tableland and then from Shoalwater Bay S along the coast and tablelands through eastern N.S.W. and Vic. to Port Phillip Bay, and also on King Is., Tas. Grows in a variety of situations but often in shallow soil on hills in open forest.
Acacia implexa var. brevipes (A.Cunn.) Domin, which G.Bentham, Fl. Austral. 2: 389 (1864), had suggested appeared to be a variety of A. melanoxylon , is distinct from both species. According to L.Pedley, Austrobaileya 1: 223 (1978), it is conspecific with the Hawaiian A. heterophylla Hook. & Arn. (= A. koa A.Gray). The type of A. brevipes A.Cunn., described from cultivated material, is at Herb. K and this disposition appears to be correct, insofar as comparative material we have seen of A. koa .
Often confused with A. melanoxylon .
Based on gross morphology of R.Coveny 5485 (BRI, CANB, K, NSW, PERTH), A. implexa possibly hybridises with A. trinervata at Grose Wold, N.S.W.
As reported by G.M.Cunningham et al ., Pl. W New South Wales 364 (1981), stock deaths have been caused by ingestion of green pods and the wood has been used for turnery work, furniture making and for fuel.
Type of accepted name
Ravines of Shoal Haven [Shoulhaven] R., N.S.W., Apr. 1824, A.Cunningham s.n. ; holo: K.
Synonymy
Racosperma implexum (Benth.) Pedley, Austrobaileya 2: 350 (1987). Type: as for accepted name.
Illustrations
F. von Mueller, Iconogr. Austral. Acacia dec. 8 [pl. 2] (1887); J.H.Maiden, Forest Fl. New South Wales 5: pl. 153 (1910); L.F.Costermans, Native Trees & Shrubs SE Australia 327 (1981); M.Simmons, Acacias Australia 229 (1981); T.Tame, Acacias SE Australia 64, , fig. 45, pl. 45 (1992).
Representative collections
Qld: Binna Burra, Lamington Natl Park, R.Cumming 3154 (PERTH). N.S.W.: Dungay Ck road, I.B.Armitage 1537 (NSW, PERTH). A.C.T.: c. 2 km N of Mt Majura, A.M.Lyne 106 (PERTH). Vic.: Briagolong State Forest, A.C.Beauglehole 77464 (MEL, PERTH). Tas.: King Is., May 1944, A.D.Hardy (MEL).
(RSC & BRM)
The information presented here originally appeared on the WATTLE CD-ROM which was jointly published by the Australian Biological Resources Study, Canberra, and the Department of Parks and Wildlife, Perth; it was produced by CSIRO Publishing from where it is available for purchase. The WATTLE custodians are thanked for allowing us to post this information here.
