Acacia acanthoclada F.Muell., Fragm . 3: 127 (1863)
Harrow Wattle
Harsh, intricate, spreading shrub 0.3–2 m high. Branchlets short, straight, rigid, patent to erect, spinescent, glabrous or pubescent. Stipules caducous, connate when young. Phyllodes erect, cuneate to obtriangular with upper apical angle obtuse and lower angle mucronulate, sometimes almost linear and then often uncinate, semi-terete when very narrow, 3–10 (–12) mm long, 0.6–4 mm wide, green or glaucous, glabrous or pubescent; nerves obscure. Inflorescences rudimentary 1-headed racemes with axes <0.5 mm long; peduncles 5–15 mm long, glabrous; basal bract small; heads globular, 4–5 mm diam., 15–30-flowered, golden. Flowers 5-merous; sepals 1/3–2/3-united; petals 1-nerved. Pods slightly constricted between seeds, twisted or coiled, 1–2 cm long (unexpanded), 2–3 mm wide, thinly coriaceous, dark brown to black, glabrous. Seeds longitudinal, 2–4 mm long, distinctly mottled, brown; aril oblique, thick.
Widespread in southern Australia from near Three Springs, W.A. through S.A. to north-western Vic. and south-western N.S.W. near Dareton.
Two subspecies are recognised.
Phyllodes green or if glaucous then not wider than 1 mm, the phyllodes and branchlets glabrous or hairy; seeds 2–2.5 mm long (widespread)
subsp. acanthoclada
Phyllodes glaucous to subglaucous (new shoots green), 2–4 mm wide, the phyllodes and branchlets glabrous; seeds 3.5- 4 mm long (W.A.)
subsp. glaucescens
Acacia acanthoclada F.Muell. subsp. acanthoclada
Shrub 0.3–2 m high. Branchlets glabrous or pubescent. Phyllodes flat or, when very narrow, semi-terete, 3–8 mm long, 0.6–3 (–4) mm wide, green, infrequently glaucous, glabrous or pubescent. Seeds 2–2.5 mm long, widely elliptic, light brown.
Widespread in southern Australia from near Wubin, W.A., through S.A. to north-western Vic. and south-western N.S.W. near Dareton. The Hewett specimen collected from Mt Lindsay in northwest S.A. is distributionally anomalous and the occurrence of this subspecies at this locality needs to be confirmed. Grows in sand or loam in a variety of vegetation types.
In W.A. this subspecies reaches a height of 1 m, but in eastern Australia it reaches 1.5–2 m, fide G.M.Cunningham et al. , loc.cit . and D.J.E.Whibley & D.E.Symon, op.cit . 48.
Phyllodes usually do not exceed 3 mm wide but in S.A. they occasionally reach 4 mm.
Acacia pulviniformis differs in having a very prostrate habit, fewer flowers per head and usually narrower and differently shaped phyllodes. Broad-phyllode forms may resemble A. ericksoniae and A. bidentata .
Type of accepted name
Sand ridges near Kulkyne, Vic., Aug. 1858, J.Dallachy ; lecto: MEL26132, fide B.R.Maslin, Nuytsia 12: 313 (1999); in the Murray desert especially near Kulkoyne [sphalm. Kulkyne, near Hattah, Vic., Dec. 1853, F.Mueller s.n .]; paralecto: MEL26130, PERTH; probable paralecto: Australia felix [‘almost certainly the Kulkyne area, far N.W.Vic., leg. F.v.Mueller, Dec. 1853’—J.H.Willis in sched.], MEL26134 (ex herb. Sonder); Kulkyn[e] and Moornpool [Mournpall] [ F.Mueller s.n .], MEL26133; Murray Desert, F.Mueller s.n ., K; Murray River [ F.Mueller ], K.
Illustrations
F. von Mueller, Iconogr. Austral. Acacia dec. 4 [pl. 6] (1887); L.F.Costermans, Native Trees & Shrubs SE Australia 309 (1981); G.M.Cunningham et al. , Pl. W New South Wales 352 (1981); B.R.Maslin, in J.P.Jessop (ed.), Fl. Central Australia 119, fig. 158G (1981); D.J.E.Whibley & D.E.Symon, Acacias S . Australia 2nd edn, 49 (1992).
Representative collections
W.A.: 36.9 km NE of Cosmo Newberry, A.S.George 2875 (PERTH); about 14.4 km due SW of Bruce Rock, B.R.Maslin 1803 (PERTH). S.A.: 16 km N of Mt Lindsay, 25 July 1980, D.Hewett s.n . (PERTH). N.S.W.: ‘Montarna’ between Buronga and Pooncarie, W.E.Mulham 1350 (NSW). Vic.: 57.8 km W of Hattah, A.C.Beauglehole 40492 (MEL).
Acacia acanthoclada subsp. glaucescens Maslin, Nuytsia 12: 314 (1999)
Shrub 0.8–1.5 m high. Branchlets glabrous. Phyllodes 5–10 mm long, 2–4 mm wide, thin, glaucous to subglaucous, light green on new shoots, glabrous. Seeds widely elliptic to ovate, 3.5–4 mm long, dark brown.
Infrequent from Koolanooka Hills (c. 20 km E of Morawa) E to Evanston (c. 110 km N of Koolyanobbing) and near Mt Correll (Mt Correll is c. 60 km WNW of Koolyanobbing), south-western W.A. Growing in clay or loam, in scrub or woodland.
Although individuals of subsp. acanthoclada may have broad glaucous phyllodes or glabrous branchlets and phyllodes, these characters do not occur in combination as in the geographically restricted subsp. glaucescens .
Resembles A. sphenophylla which is distinguished most readily by its green, clearly 2- or 3-nerved phyllodes.
Type of accepted name
Mount Gibson Stn, W.A., 29 Aug. 1976, B.R.Maslin 4232 ; holo: PERTH; iso: CANB, K, NY.
Representative collections
W.A.: 26.5 km from Three Springs on road to Perenjori, I.B.Armitage 368 (PERTH); Evanston, J.S.Beard 4760 (PERTH); 96.5 km from Wubin towards Mt Magnet, B.R.Maslin 3547 (AD, BM, BRI, G, MEL, MO, NSW, PERTH); 3.5 km NNW of Mt Correll, K.Newbey 9595 (PERTH).
(BRM)