Development of soil water repellency management options for Australian grain growers.

This project will enable growers to better manage and mitigate the impact of soil water repellency through increased understanding of crop and pasture species, stubble and farming systems on how soil water repellency occurs, in contrasting seasons and soil types.

Soil water repellency is when soils temporarily resist wetting, restricting water availability for crops. Soil water repellency affects more than 5 million hectares in Western and Southern Australia, costing growers an estimated $100 million per annum through reduced yield due to reduced crop germination, nutrient storage and availability, and plant-available water.

Currently growers use expensive and challenging techniques to manage soil water repellency. It is generally accepted that growers have knowledge of existing amelioration/mitigation methods available for managing soil water repellency because of previous GRDC projects. However, gaps and issues related to soil water repellency continue to be raised at GRDC National Grower Network (NGN) meetings. These include:

- The dependency on annual applications of soil wetters

- Difficult starts to the season
- Spatial variability of expression of soil water repellency and

- How crops and pasture residues from previous seasons (rotations) may impact the future development and severity of soil water repellency.

This project will explore these gaps and issues to develop soil water repellency management options for Australian grain growers.