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Photographer: M.W. McDonald
Photographer: B.R. Maslin
Photographer: B.R. Maslin
Photographer: J. Simmons
Photographer: J. Maslin
Photographer: B.R. Maslin
, BRM 5743, FM.jpg)
Seed from one herbarium voucher. Scale in mm. Photographer: F. McCallum
Botanical name
Acacia ampliceps Maslin, Nuytsia 1: 315, figs 1, 2 & 4A (1974)
Common name
Salt Wattle (preferred common name), River Wattle and Spring Wattle
Aboriginal name
Yirringan or Yiringan (Kurrama, Yindjibarndi, Ngarluma), Nyuuwily, NyiWily or Munturu (Nyangumarta) and Nyuuwily (Putijarra)
Description
Bushy, rather untidy, glabrous, large shrubs or small trees commonly 3-5 m tall, the largest plants reaching 6-7 (-9) m tall with trunks about 20 cm diameter at breast height, occasionally prostrate in Kimberley region, with 1-4 main stems from the base, the crowns to 6-12 m across, frequently root-suckering. Bark grey, smooth but becoming fissured and rough at base of oldest stems. Branchlets spreading to sub-pendulous, yellowish. Phyllodes normally linear to narrowly elliptic, variable in size (even on a single branch), (7-) 10-25 (-30) cm long, 7-25 (-38) mm wide, flaccid, frequently pendulous, coriaceous, straight to shallowly incurved or shallowly recurved, light to dark green; midrib rather prominent and (at least when dry) yellowish; margins often showing signs of insect damage; apex with a short, blunt point; pulvinus 2-5 mm long, transversely wrinkled. Gland prominent on upper margin of phyllode 0-3 mm above pulvinus, additional smaller gland commonly present adjacent to the apical point. Inflorescences mostly short, 2-11-headed, axillary or terminal racemes which are sometimes paniculate due to phyllode reduction; peduncles 5-15 mm long, may reach 25 mm when in fruit, stout; heads not showy, scattered over the plants, globular, large (to 15 mm diameter at anthesis when fresh), white but turning creamy yellow as stamens wither, sub- densely 25-50-flowered. Flowers 5-merous; calyx truncate or sinuate-toothed. Pods sub-moniliform, readily breaking into 1-seeded segments at the constrictions between seeds, (6-) 7-11.5 (-12.5) cm long, 4-6 mm wide, firmly crustaceous to woody, straw-coloured (yellow-brown) or pale greyish brown. Seeds longitudinal in the pods, mostly obloid, (4.5-) 5-6.5 mm long, 3-3.5 mm wide, shiny, greyish brown to black; aril scarlet (sometimes tinged orange).
Characteristic features
Rather untidy, bushy, glabrous, large shrubs or small trees (commonly 3-5 m tall but largest plants reaching 6-7 (-9) m tall). Branchlets yellowish. Phyllodes long (mostly 10-25 cm), flaccid, frequently pendulous, green, rather prominently 1-nerved, margins often showing signs of insect damage. Gland prominent at base of phyllode and commonly a smaller gland present at phyllode apex adjacent to the small, blunt point. Inflorescences mostly racemose; heads large (to 15 mm in diameter when fresh)), white, not showy. Pods long and narrow (mostly 7-11.5 cm x 4-6 mm), hard and brittle, readily breaking at constrictions between seeds. Seeds black, with a scarlet aril. Mostly grows along watercourses.
Distribution and ecology
Widespread in northwest and northern Western Australia eastwards to north-central Northern Territory. Acacia ampliceps is widespread in the Pilbara and has been recorded from Enderby Island and West Lewis islands in the Dampier Archipelago, and from the Montebello Islands; it is also possibly on Thevenard Island (about 150 km southwest of Enderby Island) but the identity of these plants needs confirmation because all material seen to date has been without flowers or fruits. It typically grows along watercourses (in sand or clay) but also occurs in swales within coastal sand hills in some areas; it commonly forms dense stands or thickets on account of its root-suckering habit.
Flowering and fruiting period
Flowers from May to August. Pods with mature seeds occur from late August to December with most in September and October.
Affinities
Acacia ampliceps belongs to a group of related species called the A. bivenosa group (see Chapman and Maslin 1992 for discussion). There are four taxa referable to this group in the Pilbara, A. ampliceps, A. bivenosa , A. ligulata and A. sclerosperma subsp. sclerosperma. Acacia ampliceps is distinguished from all these relatives by its white-coloured flower heads and its phyllode dimensions. Hybrids between A. ampliceps and both A. bivenosa (A. ampliceps x bivenosa) and A. sclerosperma (A. ampliceps x sclerosperma subsp. sclerosperma) occur in the Pilbara.
Notes
Acacia ampliceps has a moderate to fast growth rate, it is probably short-lived and both coppices and root-suckers (often forming dense stands or thickets on moist sites). It has a shallow root system and tolerates highly saline, sodic and alkaline soils (it is intolerant of acid soils). Multipurpose utilisation trials of this species abroad have shown that it establishes well by direct seeding and has potential for use in reclamation of salt-affected areas with a raised or high water table, dune stabilisation, as a low windbreak and as a fodder supplement.
The wood has an air dry density of 660 kg/m3 and burns well providing good heat and leaving a fine grey ash.
Further details on its utilisation potential, silviculture and ecological preferences are provided in Marcar et al. (1995), Turnbull (1986) and Doran and Turnbull (1997).
As reported by Juluwarlu Aboriginal Corporation (2003) Ngarluma and Yindjibarndi peoples of the Pilbara use A. ampliceps for medicinal purposes. The bark (birra) was also boiled by Kurrama people to make a (red) wash for skin sores and to bathe eyes (Young 2007). Nyangumarta people also consumed the edible yellow gum and harvested grubs (Nyamirla) from the roots. Shields were also made from larger trees. The seeds are reported by Devitt (1992) to have been eaten by indigenous people of northwestern Australia.
Conservation status
Not considered rare or endangered.
Origin of name
The botanical name is derived from the Latin amplus (large) and -ceps (head) in allusion to the large flower heads which are typical of this species.
References
Chapman, A.R. and Maslin, B.R. (1992). Acacia Miscellany 5. A review of the A. bivenosa group (Leguminosae: Mimosoideae: Section Phyllodineae). Nuytsia 8(2): 249-283.
Devitt, J. (1992). Acacias: a traditional aboriginal food source in Central Australia. pp. 37-53. In: A.P.N. House and C.E. Harwood (eds) Australian Dry-zone Acacias for Human Food. Proceedings of a workshop held at Glen Helen, Northern Territory, Australia, 7-10 August, 1991. pp. 151. (Australian Tree Seed Centre, CSIRO Division of Forestry: Canberra.)
Doran, J.C. and Turnbull, J.W. (1997). Australian trees and shrubs: species for land rehabilitation and farm planting in the tropics. ACIAR Monograph No. 24. pp. 384. (Australian Centre for International Agricultural Research: Canberra.)
Juluwarlu Aboriginal Corporation (2003). Wanggalili: Yindjibarndi and Ngarluma Plants. pp. 128. (Juluwarlu Aboriginal Corporation: Roebourne, Western Australia.)
Marcar, N.E., Crawford, D.F., Leppert, P., Jovanovic, T., Floyd, R. and Farrow, R. (1995). Trees for Saltland: a guide to selecting native species for Australia. pp. 72. (CSIRO, Division of Forestry: Australia.)
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.)
Young, L. (2007). Lola Young: Medicine Woman and Teacher. Complied by Anna Vitenbergs. pp. 160. (Fremantle Arts Centre Press: Fremantle.)