An assessment and benchmarking of phosphorus nutrient use efficiency and industry management practice in Southern Australia

Summary

Previous studies identified opportunities to improveproductivity and environmental benefits through strategic application of phosphorus fertiliser.This study examined and benchmarked industry understanding of nutrient management and current nutrient management practices, including the use of soil testing. Awareness and understanding of industry-agreed critical phosphorus values among both advisors and producers is poor, and the linkage between soil fertility, pasture production and livestock production is not well understood. Results support previous reports of low uptake of soil testing by producers - less than 25% of producers across all sectors are likely to have soils tested, and less than 15% of all tests submitted are derived from pasture paddocks. Most producers apply a traditional standard rate of fertiliser, spasmodically, irrespective of stocking rate. When pasture is fertilised it is most likely to be at the standard rate of 11kg/ha of P fertiliser.The project also examined all available soil test databases to benchmark current fertility status of pastures of the southern region. This review highlighted risks associated with using large datasets with limited metadata to draw farm or paddock level conclusions on fertility status.Datasets containing adequate metadata indicated opportunities to improve economic and environmental benefits to the red meat industry in cases of both under-fertilising and over-fertilising.  The study identifiedopportunities to improve nutrient use efficiency through routine use of soil testing and application of critical soil test values to develop farm level nutrient management strategies.