The Australian Pesticides and Veterinary Medicines Authority oversees...

The Australian Pesticides and Veterinary Medicines Authority oversees herbicide registration, requiring extensive trials to ensure crop safety and efficacy. However, due to the high cost of testing across Australia’s diverse conditions, not all soil types and climates are comprehensively covered. Registrants typically focus on environments representing the majority of the market, leaving smaller, atypical environments untested. Growers in these regions must often learn through experience, particularly with pre-emergent herbicides, which are more prone to challenges in lighter sandy soils and soils altered by amelioration practices such as claying and delving/mixing.

Stakeholder meetings have highlighted several issues with new pre-emergent herbicides, including yield losses, crop damage, and inconsistent weed control. In some cases, herbicide efficacy varies significantly across different soil types, while residues have been found to affect crop safety. Inadequate label information has also contributed to these challenges, with growers expressing concerns about poor communication from chemical companies regarding product performance and risks. In the Western and Southern regions, significant crop damage has been observed in sandy soils, along with complications related to plant-back intervals. In the Northern and Southern regions, growers have reported herbicide efficacy and safety issues in alkaline soils. The consultancy report and stakeholders involved in ULA2402-003CAX identified the evaluation of climatic, soil, and management factors affecting the efficacy and crop safety of major pre-emergent and post-emergent herbicides as a top research priority.