Precision soil mapping in Central Victorian Pastures

Summary

This Producer Demonstration Site (PDS) is designed to support adoption of precision soil testing on variable grazing paddocks in central Victoria, and demonstrate the related production, economic and environmental benefits of variable rate fertilizer applications.

Objectives

By 2024:

1. Demonstrate increased productivity that results from more precise soil and fertiliser management (PA) on four grazing properties in central Victoria.

   (a) Map the level of soil variability in pH, P, K, exchangeable cations and sulphur across paired paddocks on four host producer farms (PA treatment), and provide a comparison to the results of conventional soil testing approaches.

   (b) Undertake variable rate applications (VRA) of appropriate fertilizer/ameliorants on PA treatment paddocks according to mapped results, and continue uniform fertiliser applications on control paddocks according to the usual producer practices at each site.

   (c) Improve application efficiency across 70% of each VRA demonstration paddock, compared to a conventional uniform rate.

   (d) Measure production (livestock and pasture) differences associated with the mapped variability and the VRA practice.

2. Increase producer knowledge and skills of soil health and fertility, pasture growth rates and measurements and Precision Ag practices for 80% of participating producers.

3. Deliver a cost benefit analysis for each site comparing PA practices with existing soil testing and fertiliser practices.

4. Showcase the demonstration sites via two paddock walks/ inspections with groups each year and three combined group field days over the life of the project. Ongoing adoption of improved soil management practices (including more intensive soil sampling and VRA) is anticipated for 70% of core producers and across an additional 9,000ha for observer producers.

Progress

The Precision Soil Mapping in Central Victoria demonstration sites were established in late 2020 at four properties owned by members of the Smeaton and Pyrenees BestWool/BestLamb groups. At each site, paired paddocks representative of soil types and pasture species were grid soil-sampled to map the variability in soil characteristics. One of each pair received variable rate applications (VRA) of fertilizer/ameliorants (treatment) and the other a conventional uniform rate (control).  

The impact of these different approaches on FOO, pasture composition, pasture quality and stocking rates will be monitored regularly through to the end of 2023. The data is being analysed to answer one main question: What is the likely profit and risk of investing in VRA compared to standard practice application in local pasture systems? Complete results will be shared via field days, a series of case studies, and a formal report.  

Project facilitation and management is a collaboration between Precision Agriculture Pty Ltd and Agriculture Victoria.