In a collaborative effort, Meat & Livestock Australia (MLA), the Coorong and Tatiara district council, and Soil Function Consulting have embarked on a project to enhance grazing production on non-wetting sands in the Upper South East of South Australia.
Non-wetting sands, sometimes called hydrophobic or water-repellent sands, are sandy soils that resist water infiltration due to waxy coatings.
This contrasts with regular sandy soils that absorb water with ease. Dr Melissa Fraser, the principal consultant from Soil Function Consulting, highlighted that the project’s strategies address challenges like water repellence, soil compaction, and nutrient deficiencies.
The ultimate goal is cultivating more pasture, optimising rain-fed soil moisture, and efficiently utilising fertilisers. This would not only reduce the cost of production per hectare but also boost livestock productivity.
In 2022, a 24-ha pasture paddock named ‘Booderoo’ near Coomandook, SA, was chosen to showcase strategies countering the constraints of sandy soil. Post-soil testing, deep tillage and mixing techniques were employed to enhance the soil quality.
Dr. Fraser emphasised the importance of addressing nutrient deficiencies during the summer-to-autumn transition. She recommended the application of composts post-mixing to stabilise the soil and stimulate pasture growth. Given the region’s winter rainfall dominance, the ideal tillage, mixing, and sowing period is from mid-March to mid-April.
Forage crops selected for the project included cereal rye, vetch, and grazing brassica, known for their resilience in low-fertility, deep sandy soils. After the initial year of treatment, the cereal rye was harvested for seed and underwent grazing for the third time in the summer of 2022-23.
The Booderoo property reported positive outcomes in treating its non-wetting sands. Encouraged by these results, the team seeks other producers to test similar methods.
Dr Fraser pointed producers to the newly launched Coorong Tatiara Soil Hub website, a resource-rich platform offering guidelines to assess pastures for water repellence and other valuable information.
Mitchell Plumbe, Project Manager at MLA, stated that the project aims to enhance the understanding and adoption of effective soil amelioration practices. The tested techniques, originally developed for the cropping industry, are now being validated for cost efficiency in grazing systems.
The project evaluates various mechanical and chemical soil amendments across three sites to showcase effective methods to boost soil fertility and function.
