Mountain Cedar Wattle
Acacia elata A.Cunn. ex Benth

Synonyms - Racosperma elatum

Family: - Mimosaceae

Names:

Other Names:

Cedar Wattle.

Summary:

Mountain Cedar Wattle is a tall, spreading tree, 7-20 m high, with fissured or rough grey to black bark and green foliage with pale flattened hairs. The main leaf-axis is (30)80-220 mm long and has 2-7 pairs of branches, each of these side axes is divided into 8-22 pairs of leaflets. The leaflets are dark green on the upper surface and paler and quite hairy on the lower surface. Each leaflet is 10-60 mm long and 3-13 mm wide. The pale yellow to cream, globular flower heads are arranged in sprays. The seed pods are flat, 40-175 mm long and 9-15 mm wide, with prominent margins.

Native to New South Wales and commonly planted as an ornamental or windbreak, it is now a weed invading forest and woodland. It flowers in summer.

Description:

Cotyledons:

Two.

First leaves:

Bipinnate.

Leaves:

Alternate large, dark, glossy green on top and much paler beneath. They look rather like fern leaves.

Stipules - Present

Petiole - 25-75 (90) mm long, circular with 1 prominent, dark brown gland ¼-2/3 below basal pinnae. The base of the petiole is swollen to form the pulvinus.

Blade - The main axis (rachis) is (30)80-170 (220) mm long and has no glands or sometimes 1 gland at base of uppermost pair of side axes (pinnae). There are 2-7 pairs of side axes (pinnae), (70)100-230 mm long, with a gland often at base of upper 1-5 or more pairs of leaflets (pinnules). There are 8-22 pairs, of leaflets (pinnules) and each is lance shaped, often curved, (10)20-60 mm long by (3)5-13 mm wide and usually smooth and hairless. They are smooth and hairless or with sparse appressed hairs above and somewhat dense white or yellow, appressed hairs beneath. The midnerve is close to central, with 1 or sometimes 2 secondary nerves from the base but not reaching the margins and sometimes there are minor lateral nerves. The tip of the leaflets is acutely pointed. The lower leaflets are shorter than others.

Stems:

7-20 m high by up to 0.6 m thick.

The bark is deeply fissured and rough at the base and grey to blackish.

The branchlets circular to slightly flattened, faintly ridged, golden-hairy when young and becoming white or grey-hairy with age.

The young foliage-tips are golden or cream-coloured and silky-hairy with dark glandular hairs.

Flower head:

Pale yellow or cream-coloured.

Axillary or terminal false-panicles with 10-60 flower heads and 30-50-flowers in each head.

Axis 100-150 mm long. Flower stalks (peduncles) 2-10 mm long and hairy.

Flowers:

Bisexual. Actinomorphic.

Ovary - Superior. One carpel. Numerous ovules

Style - Threadlike

Sepals -

Petals - 5.

Stamens - Numerous and free.

Anthers - Fertile. 2 celled. Opening by longitudinal slits

Fruit:

Pod, straight-sided or slightly indented between the seeds, flattish, 40-175 mm long by 8-15 mm wide, somewhat leathery, dark brown to grey. Initially covered with dense greenish yellow fine hairs and becoming smooth and relatively hairless with age. The edges of the pod are often thickened and it opens by two valves. Seed longitudinal.

Seeds:

Thread like funicle.

Aril

Roots:

Taproot.

Key Characters:

Mature leaves bipinnate, phyllodes never produced.

Leaves with rachis 150-220 mm long; pinnules 31-60 mm long.

Lower surface of pinnules distinctly paler than the upper surface.

Pinnules >2mm wide

Flower heads on extended axillary or terminal racemes or panicles.

Flowers actinomorphic.

Ovary superior.

Stamens all free, more than 10 and usually < 0.5 mm long, white cream, yellow or orange yellow

Adapted from J.R. Wheeler, G. Harden.

Biology:

Life cycle:

Perennial. Fast growing and long lived.

Physiology:

Reproduction:

By seed.

Flowering times:

January to May in WA (according to Paczkowska & Chapman)

December to February in NSW.

Late December to March. (Aust)

Seed Biology and Germination:

Vegetative Propagules:

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

Long distance spread mainly by intentional planting then short distance spread by seed.

Origin and History:

Native to NSW.

Distribution:

NSW, QLD, SA, VIC, WA.

Darling Range and lower Southwest of WA.


Courtesy Australia's Virtual Herbarium.

Habitats:

Tall open forest, wet sclerophyll forest and rainforest, often along streams

Climate:

Temperate.

Soil:

Deep sandy soils, lateritic loam.

Plant Associations:

Jarrah woodland.

Significance:

Beneficial:

Ornamental. Commonly planted as a windbreak because it is one of the taller Acacias and is long lived.

Used for gums.

Detrimental:

Minor environmental weed naturalised in Queensland, Victoria and Western Australia.

Toxicity:

Symptoms:

Treatment:

Legislation:

None.

Management and Control:

Thresholds:

Eradication strategies:

In large dense stands, a hot fire may be used to kill old trees and encourage seed to germinate.

Cutting at the base, ringbarking or bulldozing and hand pulling seedlings provides good control as this species doesn't tend to sucker.

Good control of can be achieved by injecting the stems with 1 mL Tordon® Timber Control herbicide per 1.5 metres of height in autumn or spring when trees are actively growing. Basal bark spraying is not effective on old trees with rough bark.

Juveniles less than 2 m tall can usually be controlled by spraying the leaves until just wet with a mix of 100 mL glyphosate(450g/L) plus 25 mL Pulse in 10 L water. A concentrated mix of 1 part glyphosate with 2 parts water can also be applied using a window washer bottle. Apply about 3 mL of this solution per square metre of foliage. Lontrel®750 at 2 kg/ha may provide more selective control in some situations.

A large number of seedlings often emerge in the season after felling, burning or spraying. If these are left the infestation may become worse. Follow up every 2-3 years to ensure no trees reach an age where they set seed. Some Acacia species may be more tolerant of glyphosate than others. If glyphosate is not providing good control then try Garlon®, Grazon®, Hotshot®, Starane® or clopyralid. Test various times of treatment in your area. Avoid further burning or denuding of the area as this will encourage seedling establishment.

Don't buy or plant them in gardens outside their native range in NSW.

Herbicide resistance:

None reported.

Biological Control:

Related plants:

See A key for weedy Acacias and similar native species

There are more than 500 native Acacia species in WA.

Weedy Acacias include
Acacia Hedge (Acacia paradoxa). Noxious weed.
Black Wattle (Acacia mearnsii) Bark used in tanning.
Black Wattle (Acacia pycnantha)
Blackwood (Acacia melanoxylon) Bark used in tanning
Blakely's Wattle (Acacia blakelyi) Used in revegetation.
Brigalow (Acacia harpophylla)
Caterpillar Wattle (Acacia lasiocalyx) Used in revegetation.
Chisholm's Wattle (Acacia chisholmii)
Coast Myall (Acacia binervia) is toxic to stock.
Cootamundra Wattle (Acacia baileyana) Ornamental
Curracabah (Acacia concurrens)
Currawong (Acacia burrowii)
Cutch Tree (Acacia cutechu) Noxious weed.
Deane's Wattle (Acacia deanel)
Flinders Ranges Wattle (Acacia iteaphylla)
Green Wattle (Acacia decurrens)
Gidgee (Acacia cambagei)
Georgina Gidgee (Acacia georginae) is toxic to stock.
Golden Wattle (Acacia pycnantha)
Golden-wreath Wattle (Acacia saligna) Used in revegetation.
Gosford Wattle (Acacia prominens) Ornamental
Hop Mulga (Acacia craspedocarpa)
Manna Wattle (Acacia microbotrya) Used in revegetation.
Mimosa bush (Acacia farnesiana)
Motherumbah (Acacia cheelii)
Mountain Cedar Wattle (Acacia elata)
Mulga (Acacia aneura) Used for fodder.
Prickly Acacia (Acacia nilotica). Noxious weed.
Prickly Moses (Acacia pulchella)
Queensland Silver Wattle (Acacia podalyriifolia)
Silver Wattle (Acacia dealbata)
Snowy River Wattle (Acacia boormanii) Ornamental
Sydney Golden Wattle (Acacia longifolia)
White Sally (Acacia floribunda)
Racosperma species.

Acacia glaucescens is toxic to stock.

Plants of similar appearance:

Karri Wattle (Acacia pentadenia) has shorter leaflets at 3-6 mm and fewer (2-4) flower heads.

Albizia (Paraserianthes lophantha) has smaller leaflets 5-10 mm long and 1.5-3 mm wide and also has large cylindric flower heads that are 3-6 cm long.

References:

Bodkin, F. (1986). Encyclopaedia Botanica. (Angus and Robertson, Australia).

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney).

Harden, Gwen J. (1991). Flora of NSW. (Royal Botanic Gardens, Sydney). Volume 2. P386. Diagram.

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (2007). Western Weeds. A guide to the weeds of Western Australia. (Second Edition). Plant Protection Society of Western Australia, Perth, Western Australia. P191. Photo.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).

Lazarides, M. and Cowley, K. and Hohnen, P. (1997). CSIRO handbook of Australian Weeds. (CSIRO, Melbourne). #3.9.

Moore, J.H. and Wheeler, J.R. (2008). Southern Weeds and their Control. (Second Edition). Department of Agriculture and Food Western Australia. P165. Photos.

Paczkowska, G. and Chapman, A. (2000). The Western Australia flora: a descriptive catalogue. (Wildflower Society of Western Australia (Inc), the Western Australian Herbarium, CALM and the Botanic Gardens & Parks Authority). P307.

Randall, J.M. and Marinelli, J. (1996) Invasive Plants. (Brooklyn Botanic Gardens Inc. Brooklyn). P. Photo.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.