Weeds of Australia - Fact Sheet

Top Scientific Name Synonyms Family Common Names Origin Naturalised Distribution Notes

Scientific Name

Acacia retinodes Schltdl. var. retinodes

Synonyms

Acacia floribunda hort. ex G. Nicholson
Acacia fragrans hort. ex Pottier
Acacia longissima hort. ex Chopinet
Acacia provincialis A. Camus
Acacia retinodes Schltdl. var. floribunda H. Vilm.
Acacia rhetinodes J.M. Black, orth. var.
Acacia semperflorens hort. ex A. Berger
Racosperma retinodes (Schltdl.) Pedley
Racosperma retinodes (Schltdl.) Pedley var. retinodes

Family

Fabaceae: sub-family Mimosoideae (New South Wales)
Leguminosae (South Australia)
Mimosaceae (Queensland, the ACT, Victoria, Tasmania, Western Australia and the Northern Territory)

Common Names

everblooming acacia, ever-blooming wattle, silver wattle, swamp silver wattle, swamp wattle, water wattle, wirilda, wirilda wattle

Origin

Native to some parts of southern Australia (i.e. south-eastern South Australia and western Victoria). It occurs naturally on Kangaroo Island and in the Mount Lofty Ranges in South Australia, and from the Glenelg River to near Melbourne in Victoria.

Note: two distinct forms of this plant have been recognised, based on differences in morphology and the habitats in which they tend to grow. The first of these, which is known as the "typical variant" or "hill variant", is naturally restricted to the Mount Lofty Ranges region in South Australia, where it extends from Mount Bryan south through the Barossa Valley and the Adelaide Hills to Delamere on the Fleurieu Peninsula. This variant grows in fertile soils and on rocky hillsides away from water. The second variant, which is called the "swamp variant", is found over the entire range of wirilda wattle (Acacia retinodes var. retinodes), but generally grows in damp soils in swamps and along watercourses.

Naturalised Distribution

Naturalised beyond its native range in Victoria and the "typical variant" is naturalised beyond its native range in some parts of south-eastern South Australia.

Also naturalised overseas in parts of southern USA (i.e. California and Florida).

Notes

Wirilda wattle (Acacia retinodes var. retinodes) is regarded as an environmental weed in Victoria and is considered to pose a serious threat to one or more vegetation formations in this state. It appears on several local and regional environmental weed lists (e.g. in Knox City, Hume City, Mornington Peninsula Shire and the Goulburn Broken Catchment) and has been recorded in conservation areas (e.g. Yarra Bend Park in suburban Melbourne). It is probably of most concern on the Mornington Peninsula.

While wirilda wattle (Acacia retinodes var. retinodes) is native to some parts of Victoria, non-local forms from South Australia (i.e. probably the "typical" variant) are weedy and are considered to be environmental weeds. Such forms are not recommended for planting near areas of conservation significance in Hume City Council. It has also been suggested that local forms of this species may become weedy in bushland areas if they are managed incorrectly (i.e. the frequency of fires is reduced). However, this may once again be because non-local forms are causing the problems.

The "typical" variant of wirilda wattle (Acacia retinodes var. retinodes) has also become locally naturalised outisde its native range near Mount Gambier in south-eastern South Australia, where it has spread from deliberate plantings to form small colonies.