Botanical name

Acacia ancistrocarpa Maiden & Blakely, J. Roy. Soc. W. Australia 13: 31, pl. 21, figs 1-6 (1928)

Common name

Fitzroy Wattle (preferred common name), Fish-hook Wattle, Pindan Wattle and Shiny Leaved Wattle

Aboriginal name

Murnungu (Yindjibarndi), Murnungu or Pulburing (Ngarluma), Balberin or Palpurin (Kurrama), Parlpirr (Putijarra), Wilarra (Thalanyji) and Parlpi (Nyangumarta)

Description

Multi-stemmed, obconic, spreading, glabrous shrubs 1.5-4 m tall, the ultimate branchlets sometimes sub-pendulous. Bark grey, longitudinally fissured towards base of mature stems otherwise smooth. New shoots resinous (but not sticky). Phyllodes linear to very narrowly elliptic, (4.5-) 6-18 cm long, (2-) 3-10 (-13) mm wide, not rigid, straight or shallowly falcately recurved, somewhat shiny, bright olive-green; parallel longitudinal nerves numerous, very indistinct, somewhat widely spaced, 1-3 nerves slightly more evident than the rest; marginal nerve discrete and yellowish; apex frequently acuminate, not pungent. Glands inconspicuous, 2 or 3 along upper margin of phyllodes. Inflorescences simple, rarely rudimentary racemes 0.5-3.5 mm long; peduncles 5-15 (-25) mm long; spikes normally scattered over the plants and not especially showy, 1.5-3 (-4.5) cm long, golden, the flowers not particularly densely arranged. Flowers 5-merous; calyx shortly dissected. Pods narrowly oblong, flat but shallowly raised over seeds, straight-edged or slightly constricted between seeds, 5-9 (-11) cm long, 7-12 (-15) mm wide, often erect, crustaceous to sub-woody, splitting first along the edge opposite the seed attachment then opening elastically from the apex to forcibly eject the seed (the dehisced valves recurved), straight or shallowly curved, ąresinous (but not sticky), obliquely reticulately nerved, mid-brown to dark brown, apex ąhooked; marginal nerve thick. Seeds oblique in the pods, seated in shallow depressions separated by narrow partitions, obloid to obloid-ellipsoid or ąovoid, 5-7 mm long, ąshiny, dark brown except sometimes the pleurogram bordered by a diffuse band of dull yellow tissue; funicle/aril conical, creamy white (darker coloured near attachment to seed).

Characteristic features

Multi-stemmed, obconic, glabrous shrubs. Phyllodes long and relatively narrow (6-18 cm x 3-10 mm), not rigid, somewhat shiny, bright olive-green, parallel longitudinal nerves indistinct and somewhat widely spaced. Glands inconspicuous, 2 or 3 along upper margin of phyllodes. Spikes normally scattered over the plants and not especially showy. Pods flat, often erect, crustaceous to sub-woody, splitting first along one edge then opening elastically from the apex to forcibly eject the seed, the dehisced valves recurved, obliquely reticulately nerved, brown, apex ąhooked; marginal nerve thick.

Distribution and ecology

Widespread and common in the northern and central arid zone from northwest Western Australia through Northern Territory to far western Queensland. Acacia ancistrocarpa is very widespread in the Pilbara and although it is common in places where it occurs, it generally does not form dense stands. However, it does regenerate readily from seed following fire or ground disturbances and in these situations it can form moderately dense populations, especially along road verges. Grows on mainly acidic, deep red sand or skeletal soils in spinifex communities, mostly on plains.

Flowering and fruiting period

It is likely that flowering and fruiting in this species is dependent upon the timing and intensity of rainfall events. While flowers may be present on some Pilbara plants from January to September the main flowering flush is April to July. Pods with mature seeds have been collected in September and October. According to Turnbull (1986) seeds may occur to December but it is not known if this applies to plants from the Pilbara.

Affinities

In many places around the Pilbara (especially the northern regions) A. ancistrocarpa hybridizes with A. stellaticeps (see A. sphaerostachya). Rare putative hybrids also occur with A. citrinoviridis (see A. ancistrocarpa x citrinoviridis), A. arida (a single flowering plant in a population of A. ancistrocarpa and A. arida from near Roebourne; not able to be relocated in recent years) and A. orthocarpa (a rare sterile individual within a population of A. ancistrocarpa and A. orthocarpa on Abydos-Woodstock Reserve south of Port Hedland; not able to be relocated in recent years). Plants described by Maslin (1983) as A. ancistrocarpa x trachycarpa are now referable to A. trachycarpa x tumida var. pilbarensis.

Notes

Acacia ancistrocarpa has been observed to coppice from the base following fire but Beard (1975) indicates that it is usually killed by fire and regenerates profusely from seed.

According to Turnbull (1986) it has potential to produce small-sized firewood and could be used for erosion control and for low shelter; however, limited multipurpose utilisation trials in Niger and Upper Volta have shown poor results.

This species is not eaten by stock to any extent.

This species is used extensively in the land rehabilitation industry in the Pilbara as seed is produced prolifically and easy to collect. Its preference for disturbed sites also enhances it use in land rehabilitation programs as does is rapid growth and bush habit. Treating seed by immersion in boiling water prior to planting significantly enhances germination success to over 90% in freshly collected seed (Fox and Dunlop 1983).

As reported by the Juluwarlu Aboriginal Corporation (2003) Yindjibarndi and Ngarluma peoples of the Pilbara used A. ancistrocarpa for medicinal purposes. The phyllodes and twigs were crushed with a barru (grinding stone) then soaked or boiled in water. The liquid was then used to bathe sores or to soak a cloth to wrap the head to relieve headaches. The twigs were heated until sweating, then applied to swellings to draw out the fluid and to relieve pain. The liquid was also drunk by the Nyangumarta to relieve cold symptoms. The roots of this species are a source of edible bardi grubs, the seeds are ground to make flour and the green seeds can be eaten raw. In Central Australia indigenous people reputedly eat the seed which is normally gathered from around ant nests, and the phyllodes are used to smoke babies as a treatment for diarrhoea (Latz 1999).

Conservation status

Not considered rare or endangered.

Origin of name

The botanical name is derived from the Greek ankistron (fish-hook) and karpos (fruit), probably in reference to the hooked tip of the pod.

References

Beard, J.S. (1975). Vegetation survey of Western Australia - Pilbara. (University of Western Australia Press: Nedlands.)

Fox, J.E.D. and Dunlop, J.N. (1983). Acacia species of the Hamersley Ranges, Pilbara Region of Western Australia. Mulga Research Centre. Occasional Report No. 3. pp. 94. (Western Australian Institute of Technology: Bentley.)

Juluwarlu Aboriginal Corporation (2003). Wanggalili: Yindjibarndi and Ngarluma Plants. pp. 128. (Juluwarlu Aboriginal Corporation: Roebourne, Western Australia.)

Latz, P.K. (1999). Pocket Bushtucker: a field guide to the plants of Central Australia and their traditional uses. pp. 215. (IAD Press: Alice Springs.)

Maslin, B.R. (1983). Studies in the genus Acacia (Leguminosae: Mimosoideae) - 14. New taxa from north-west Western Australia. Nuytsia 4(3): 383-410.

Turnbull, J.W. (ed.) (1986). Multipurpose Australian trees and shrubs: lesser-known species for fuelwood and agroforestry. pp. 316. (Australian Centre for International Agricultural Research: Canberra.)