Enhancing Arable Weed Diversity by Reduced Herbicide Use?

Abstract Based on a workshop held at the German Weed Science Conference in February 2024, this paper explores strategies for reducing herbicide use in arable cropping systems to enhance weed diversity. Although potentially detrimental to crop yields, weeds play a vital role in supporting ecosystem functions such as pollination, nutrient cycling, and microbial diversity. The reduction of herbicide use is regarded as an important management strategy for preserving weed biodiversity, which has been declining in Europe. Three strategies for reducing herbicide use are discussed: site-specific herbicide application, species-specific herbicide dose rates, and the use of selective herbicides with narrow target spectra. Each strategy is evaluated for its technical feasibility, agronomic risks, and potential benefits for weed diversity. While challenges such as high investment costs, technical limitations, and the need for precise weed distribution data remain, emerging technologies like AI-driven weed detection and autonomous robots offer promising solutions. The paper emphasizes the importance of combining reduced herbicide use with other management practices, such as crop rotation and mechanical weeding, to achieve sustainable and ecologically beneficial weed control. A shift in farmers’ perspectives on “clean fields” and more comprehensive guidance on the ecological value of weeds is essential for the widespread adoption of these strategies.