Quantifying changes in the environmental impact of in-crop herbicide use in Saskatchewan, Canada

Abstract

The sustainable management of herbicides is critical to modern agriculture and the environment. This article examines the evolution and environmental implications of herbicide use in Saskatchewan agriculture. It quantifies changes in herbicide use and their environmental impacts by analyzing farm-level herbicide use data from 1991-1994 and 2016-2019 through the Environmental Impact Quotient. Results confirm significant reductions in both the environmental and toxicological impacts of herbicides used, underlining the pivotal shift from tillage-based weed control to herbicide-resistant cropping systems. The environmental impact of the top five herbicides used from 2016-19 is 65% lower than those used from 1991-94, with a 45% reduction in the active ingredient applied per acre. Despite increased herbicide usage due to more crop acres being seeded, the findings highlight a marked improvement in the sustainability of herbicide use, affirming the importance of technological advancements in agriculture. This research contributes valuable insights into long-term trends in herbicide use, offering a practical framework for informed decisions aligning with sustainable agricultural practices as well as reduced biodiversity impacts.