Zoning up to optimize pasture production

Summary

To demonstrate the treatment of constraining soil nutrient deficiencies by zone at variable rate application will provide optimal pasture yield, sustainable livestock production per hectare and profitable returns for livestock producers in the New England.

Objectives

By November 2025 in the New England area across five demonstration sites:

1. Validate site-specific management of fertiliser and soil amendment treatments using soil nutrient zone mapping of sub-paddock soil nutrient variability to increase pasture production in a grazing system by 20% per hectare and livestock productivity by 25% over existing fertiliser applications.

2. Demonstrate that targeted treatments by zone will achieve potential optimal pasture biomass production over at least 90% of the treated paddock or farm.

3. Prove the cost benefit of investing in spatial imagery, grid sampling and site-specific management to define variable fertiliser application zones that will lead to livestock production gains and soil treatment savings.

4. Fine tune the pasture production response curves already established for the New England region.

5. Conduct an annual field day and other extension activities to showcase the demonstration site results and encourage adoption of key practices to result in:

• 100% of core producers (5) fully implementing the practice of soil nutrient zone mapping and variable fertiliser application across their pasture and livestock operations.
• 10% of observer producers (15) fully implementing the practice of soil nutrient zone mapping and variable fertiliser application across their pasture and livestock operations.
• 100% of core producers and 80% of observer producers having greater knowledge and skills in the value of zoning paddocks for soil nutrient variation.

Progress

This PDS project comprises six sites in the New England region of NSW and is currently in Year 5 of a 6 year project, the project is coordinated by Precision Pastures.

Soil phosphorus and pH levels have been grid-sampled annually, and variable-rate fertiliser application plans have been mapped. Where participants applied lime/fertiliser over the past year, an improvement in the total project-area under the optimal level of phosphorus/lime was recorded, and there was a reduced variability in sub-paddock pH/phosphorus levels.

Trial pasture plots have indicated that pasture growth rates have correlated with soil phosphorus and pH levels, with optimal pH and phosphorus levels leading to earlier and higher pasture growth rates.

A field walk on pasture assessment and feed budgeting was conducted in April 2024 to enhance participant’s skill in optimally utilising their pastures. A total of twelve participants were present, with representation from across the region.