The ecological and economic benefits of sustainable agricultural practices: Evidence from on‐farm trials in broad‐acre crops

A transition to more sustainable agricultural practices is essential to mitigate the negative environmental impacts of conventional farming and to ensure long‐term food security. However, widespread adoption requires robust evidence demonstrating their efficacy and economic viability. We co‐designed a two‐year field trial with farmers and agronomy advisors in Australia to evaluate the ecological and economic benefits of sustainable agricultural practices for managing the redlegged earth mite, a major pest of Australian crops and pastures. We compared ‘Novel’ treatments—representing long‐term farmer‐implemented sustainable practices based on biological control—with ‘Conventional’ treatments and ‘Plus’ treatments designed as counterfactuals to disentangle the effects of specific pest control and plant nutrient components. Redlegged earth mite densities remained below economic thresholds across all treatments and years, demonstrating effective pest control in both conventional and sustainable systems. Notably, the Novel treatment supported higher densities of beneficial arthropods, suggesting increased biological control potential. Yield and gross profit margins were generally similar across treatments, indicating that sustainable agriculture practices can maintain profitability while fostering biodiversity. Practical implication. Our study provides evidence that biological control and biofertiliser supplementation can be effectively used to manage agricultural pests. It also demonstrates the value of close collaboration with farmers and agronomy advisors in conducting ecological field research with real‐world applications.