Acacia olsenii Tindale, Telopea 2: 123; 122, fig. 4 (1980)
Tree 3–15 m high. Bark smooth, later sometimes slightly corrugated towards base, grey-green, dark grey, brown or black. Branchlets angled or vertically flattened towards apices, mostly glabrous, rarely minutely hairy along non-prominent ridges, pruinose. Young foliage-tips brownish green or cream-coloured. Leaves dark green; petiole above pulvinus 1.3–3.5 cm long, vertically flattened, glabrous or sometimes with sparse, short, white hairs, bluish glaucous, with 1 prominent, spherical, usually glabrous gland at or near base of lowest pair of pinnae; rachis 4.5–10 cm long, vertically flattened, usually with a spherical gland at base of all pairs of pinnae, sometimes also with 1–4 smaller, often contiguous, interjugary glands between some pairs of pinnae; pinnae 9–17 pairs, 3.5–8.3 cm long; pinnules 50–106 pairs, oblong to cultrate, mostly 1–2.2 mm long and 0.4–0.5 mm wide, ciliolate otherwise glabrous, apex subacute. Inflorescences in axillary or terminal false-panicles. Heads 7–12-flowered, deep yellow. Pods usually slightly constricted between seeds, 2.5–12 cm long, 6–8 (–12) mm wide, thinly coriaceous, dark brown or blackish, bluish pruinose, glabrous; margin prominent.
Occurs on the Southern Tablelands of N.S.W. from Minuma Ra. S to Mother Woila, Tabletop Mtn and Tuross R. Often grows in stands usually within 50 m of creeks, on very steep, dry, rocky hillsides facing NW, at heads of gullies and tops of knife-edge ridges, in open forest, on scree, mostly on slate or shale, sometimes in alluvial sands. Flowers May.
Acacia storyi is very closely allied to A. olsenii but differs as follows: heads cream-coloured or pale yellow and 14–20-flowered, often less numerous pairs of pinnules and margins of the pinnules with fewer white cilia. There is a considerable disjunction in the distribution of these two species, as A. olsenii occurs in south-eastern N.S.W., whereas A. storyi is endemic to Blackdown Tableland, Qld.
Type of accepted name
3.2 km ENE of Dampier trig on Bendethera Caves fire trail, 53 km SSW of Braidwood, N.S.W., 18 May 1975, R.Coveny 6532, P.Hind & M.Parris ; holo: NSW; iso: A, AD, B, BRI, CANB, CHR, K, L, LE, MEL, NSW, NU, P, PERTH, UC, US, Z.
M.D.Tindale, loc. cit .; D.A.Morrison & S.J.Davies, in G.J.Harden (ed.), Fl. New South Wales 2: 389 (1991).
N.S.W.: Mother Woila Mtn, 26 Apr. 1980, J.Benson (NSW); E of Big Badja Hill, M.D.Crisp 2377, D.J.Cummings & A.Tyrrel (CANB, NSW); NW face of Mother Woila Peak, F.Grossbechler CBG817372 (CANB, NSW); Mother Woila, I.Olsen 3094 (CANB, K, L, MEL, NSW, TL, UC, US, Z); Razorback ridge approach to Mother Woila, I.Olsen 3091 (AD, PERTH).
(MDT & PGK)