Wimmera Southern Mallee (region)

Wimmera Southern Mallee Region Victoria
Mount Arapilesrises above the flat Wimmera plain.
Population	54,645 (2011 census)
• Density	1.302219/km2(3.37273/sq mi)
Area	41,963 km2(16,202.0 sq mi)
LGA(s)	Shire of Hindmarsh Rural City of Horsham Shire of Northern Grampians Shire of West Wimmera Shire of Yarriambiack
Region	Grampians
State electorate(s)	Lowan Ripon
Federal division(s)	Mallee
Localities around Wimmera Southern Mallee Region: Murray Mallee Mallee Loddon Limestone Coast Wimmera Southern Mallee Region Goldfields Limestone Coast Western District Central Highlands

The Victorian government'sWimmera Southern Malleesubregionis part of theGrampians regionin westernVictoria.It includes most of what is considered the Wimmera, and part of the southernMalleeregion. The subregion is based on the social catchment ofHorsham,its main settlement.

The Wimmera district covers the dryland farming area south of the range ofMalleescrub,east of theSouth Australiaborder and north of theGreat Dividing Range.

Most of the Wimmera is very flat, with only theGrampiansandMount Arapilesrising above vast plains and the lowplateauxthat form the Great Divide in this part of Victoria. The Grampians are very rugged and tilted, with many sheer sandstone cliffs on their eastern sides, but gentle slopes on the west.

The Wimmera does not include the southern Mallee area in the north part of theShire of Yarriambiack(aroundHopetoun). It does include the southern part of theShire of Buloke,which is not part of the Victorian government's aforementioned subregion (aroundWycheproof,Birchip,DonaldandCharlton). This latter area, plus theSt Arnaudarea, makes up the East Wimmera region.

In the context of theInterim Biogeographic Regionalisation for Australia,the Wimmera is a sub-region of 2,145,380 hectares (5,301,300 acres) located within theMurray Darling Depressionbioregion.

The Wimmera is one of the nine districts in Victoria used for weather forecasting by theAustralian Bureau of Meteorology.

TheVictorian Department of Environment and Primary Industriesdefines the Wimmera as a 30,000-square-kilometre (12,000 sq mi) region for agricultural production purposes encompassing theBuloke,Hindmarsh,Horsham City,Northern Grampians,West WimmeraandYarriambiacklocal government areas.

The Victorian Government's Wimmera Catchment Management Authorityserves the catchment of theWimmera River,and that of theYarriambiack Creeksouth of the Mallee.

TheShire of Wimmeraoriginally covered a large part of the Wimmera and southern Mallee, but retracted over time to cover only land near Horsham. It was later abolished, with most of being becoming part of theRural City of Horsham.

The federal governmentDivision of Wimmeraoriginally covered roughly the same area as theDivision of Malleedoes today, but ended its life covering only the Wimmera area.

At the2011 census,the six local government areas (LGAs) that are thought to comprise the Wimmera had a combined population of 54,645. The area of these same six LGAs is 41,963 square kilometres (16,202 sq mi).

History

The area was inhabited by its Indigenous residents (and continues to be) when it was surveyed by the first European to do soThomas Mitchellin the mid-1830s, and he is credited with naming the Grampians after a mountain range in his native Scotland,and naming the region as Wimmera, adapting a word from the local indigenous language meaning 'throwing stick'.

Regional development and population

The area contains a number of important towns, such asHorsham,Warracknabeal,Dimboola,StawellandNhill.Almost all of these are largely dependent on thegrainandsheepindustries, and landscape is heavily dominated byflour millsand grainstorage silos.The smaller towns in the area are dying due to the declining value of primary products that dominate the region'seconomy.Similarly, modern farm technology allows individual farmers to stay viable by farming more land, but the decreasing population, and better transport, make smaller service centres less and less viable.

Wimmera district LGA populations

Local government area	Area		Population (2011 census)	Source(s)
	km2	sq mi
Shire of Buloke1	8,004	3,090	6,384
Shire of Hindmarsh	7,527	2,906	5,798
Rural City of Horsham	4,249	1,641	19,279
Shire of Northern Grampians	5,918	2,285	11,845
Shire of West Wimmera	9,107	3,516	4,251
Shire of Yarriambiack	7,158	2,764	7,088
Totals	41,963	16,202	54,645

^1The Shire of Buloke is included in both theMalleeand the Wimmera districts; hence the imprecise definition.

Climate

The climate is semi-arid to sub-humid, with annual rainfall ranging generally from 380 millimetres (15 in) in the north to 580 millimetres (23 in) in the south. In the Grampians, annual precipitation can be as high as 1,150 millimetres (45 in) and snowfalls are not uncommon. Most rain falls in winter, though heavy summer falls can occur, the most famous of which was thethunderstormthat dumped 133.2 millimetres (5.24 in) onNhillin mid-January 1974.

Temperatures are hot in summer, ranging typically from a maximum of 30 °C (86 °F) to a minimum of 14 °C (57 °F), whilst extremes can be as high as 46 °C (115 °F). In the winter, maximums are 15 °C (59 °F), but mornings can be cool, averaging atHorsham4 °C (39 °F).

Geography

Most of the soils are very infertile and many are sandy; however in a narrow belt between Nhill andWarracknabealthere are heavy greyVertisols,that, although still deficient inphosphorus,are otherwise free of major nutrient deficiencies and are able to hold water very well. These grey soils are the principalwheatsoils of Victoria. Red-brown earths are also used for wheat but do not give as high yields and require more fertilisation.

TheWimmera Riverflows from the Pyrenees Ranges, across the northern foothills of the Grampians then towardsLake Hindmarsh.Many streams in the region flow only after sustained heavy rainfall and are often dry for long spells. In recent yearsRocklands Reservoir,the main water storage of the district, has been consistently at unusually low levels due to a succession of dry years.

Natural heritage

The Wimmera is renowned for its natural heritage.

One of the key preservation areas is contained within theGrampians National Park,which possesses many unusual wildflowers and the greatest diversity of flora and fauna in Victoria west of theSnowy River.The Grampians also possess many importantAboriginalartifacts. A local Aboriginal nameGariwerdwas adopted by the National Park in 1991 in recognition of this fact; however, this change was soon reversed after a change of state government in 1992.

TheLittle Desert National Park,south of Nhill and west of Dimboola, is a large wilderness area of sand dunes that were too infertile for productive farming even withsuperphosphateand trace elements.

See also

• Geography of Victoria
• Regions of Victoria