Acacia williamsonii Court

Whirrakee Wattle

Muelleria 2: 163 (1972) APNI

Taxonomic status:Accepted

Occurrence status:Endemic

Establishment means:Native

Threat status:Victoria: rare (r)

Bushy shrub to 2 m high; branchlets glabrous. Phyllodes inclined to ascending (often patent at ends of flowering branchlets), narrowly linear, 4–9 cm long, 1.5–3 mm wide, usually slightly curved, not rigid, glaucous (or green or sub-glaucous at ends of flowering branchlets), glabrous, narrowed at base; midrib not prominent, lateral veins absent; gland 7–27 mm above pulvinus, often absent. Racemes with rachis usually 1–3 cm long, glabrous, normally drying dark reddish-brown; peduncles 2–3 mm long, rather stout, glabrous, sometimes with appressed, minute hairs, drying dark reddish-brown to blackish; heads globular, subdensely 15–20-flowered, bright golden; bracteole lamina more or less circular, dark brown to blackish, white-fimbriate. Flowers 5-merous; sepals united. Pods usually more or less moniliform, to 9 cm long, 3–3.5 mm wide, firmly chartaceous to somewhat crustaceous, glabrous, black; seeds longitudinal, oblong to elliptic, 3.5–4 mm long, somewhat shiny, black, aril clavate. Flowers Aug.–Sep.

Gold, VRiv, VVP. Endemic. Restricted to north-central Victoria where occurring from Inglewood to Rushworth, and particularly common in the Whipstick Forest near Bendigo where growing on stony gravel or clay-loam in open Eucalyptus forest and mallee open-scrub. A specimen collected from north of Cobar in New South Wales is assumed to have been introduced to that area.

A variant from near Rushworth is characterized by very long racemes (to 9 cm), and linear legumes which are only slightly constricted between the seeds.

Closely allied to A. hakeoides which differs in its wider, green phyllodes, 20–27-flowered heads and 4–6 mm wide pods with dull seeds 5–6.5 mm long.

Putative hybrids between A. pycnantha and A. williamsonii occur in the Whipstick Forest.

Source: Entwisle, T.J.; Maslin, B.R.; Cowan, R.S.; Court, A.B. (1996). Mimosaceae. In: Walsh, N.G.; Entwisle, T.J. (eds), Flora of Victoria Vol. 3, Dicotyledons Winteraceae to Myrtaceae. Inkata Press, Melbourne.
Updated by: Val Stajsic, 2018-08-27
Hero image
Distribution map
life Life
kingdom Plantae
phylum Tracheophyta
superorder Rosanae
order Fabales
family Fabaceae
genus Acacia
Higher taxa

Victoria

Source: AVH (2014). Australia's Virtual Herbarium, Council of Heads of Australasian Herbaria, <http://avh.chah.org.au>. Find Acacia williamsonii in AVH ; Victorian Biodiversity Atlas, © The State of Victoria, Department of Environment and Primary Industries (published Dec. 2014) Find Acacia williamsonii in Victorian Biodiversity Atlas
  Bioregion Occurrence status Establishment means
Victorian Volcanic Plain present native
Victorian Riverina present native
Gippsland Plain present cultivated
Goldfields present native

State distribution

Distribution map
State
South Australia
New South Wales
Australian Capital Territory
Victoria