Wimmera land and soils are important natural assets that underpin the region’s agricultural industry and valued natural landscapes.

This section focuses on land use and management and how it underpins soil health.

Almost 80% of the Wimmera’s landscape supports a large agricultural industry which significantly contributes to the region’s economy and food security at a global and national scale.(21) Grain production is the Wimmera and southern Mallee’s biggest industry, providing 26% of Victoria’s grains, being cereals, legumes and oilseeds. This is followed by 16% of Victorian sheep meat production and 17% of Victoria’s wool production.(22) Viticulture, olives and native flowers are also significant primary industries in the region. The Pyrenees region, divided between the North Central and Wimmera regions, supports a significant wine industry, producing $56 million in outputs and a value add of $11.5 million.(23) The remaining 20% of land comprises national parks, crown land and urban areas. Figure 10 shows the coverage of different land use cover classes in the Wimmera.

Healthy soils have the physical, chemical and biological processes working together to support productivity, maintain environmental quality and promote plant and animal health.(24)

Percentage of land use cover classes in the Wimmera for the period 2015-2019.
Dryland cropping 53%, Native trees 17%, Native pasture and grasslands 13%, Pasture (not native) 10%, Native scattered trees 3%, Water and wetlands 2%, Natural low cover 1%, Native shrubland 1%, Irrigated horticulture 0.5%, Urban built up and disturbed ground 0.5%, Plantations (pine and hardwood) 0.4%.

Figure 10: Percentage of land use cover classes in the Wimmera for the period 2015-2019(25)

The management of soils influences the health of natural assets, such as native vegetation and waterways by providing a healthy foundation for plants and animals and acting as a buffer to prevent sediments entering waterways.

Informed land management decision-making is critically important for sustaining this finite, fragile and complex resource into the future.

First Nations people’s connection to country is formed through a deep understanding and appreciation of the landscape. This provides a rich source of knowledge that can improve land and soil management policies and practices.

Wimmera soils have evolved over millions of years and can be grouped into four areas with common soil types and distinct landscape characteristics (Figure 11):

  1. Upper catchment
    • Steep hillsides and valleys are covered (60% of the area) by alluvial and volcanic clays and texture contrast soils where sandy and loamy surface soils overlay heavy clay subsoils.
    • Supports a mixture of livestock and cropping.
    • Supports Gariwerd (Grampians) and Burrunj (Black Range), many public reserves and important waterways.
  2. North eastern plains
    • Characterised by hummocky dunes, flat plains, rises and lake lunettes. About 75% of the area is comprised of cracking and self-mulching clays that shrink and swell with changing moisture content.
    • Supports the largest area of cropping in the Wimmera plus important waterways.
  3. North western plains
    • Regular, parallel dunes or ridges alternate with swales or depressions. Scattered lakes and lunettes are also present. Ninety per cent of the area is covered by sodic clays in the swales and siliceous dunefield sands.
    • Supports predominately cropping plus the Little Desert and scattered reserves and wetlands.
  4. South west Wimmera
    • Predominantly ridge and swale systems. Eighty- seven per cent of the area is covered by sodic clays and texture contrast soils.
    • Supports a mixture of livestock and cropping plus a high density of wetlands and native vegetation.
Map of Regional soil types grouped into four areas with common soil types and distinct landscape characteristics.

Figure 11: Regional soil types and localised threats