Strategies and tactics for herbicide use reduction in field crops in Canada: A review

Abstract

There are many economic and health reasons for reducing pesticide use in Canada. Herbicide use on field crops is by far the most common pesticide use in Canada. This paper is a review of four topics related to herbicide use reduction on field crops in Canada: (1) broad strategies and (2) specific tactics for herbicide use reduction; (3) factors affecting adoption; and 4) research approaches for improving the implementation of herbicide use reduction. Numerous tactics exist to use herbicides more efficiently and herbicides can sometimes be replaced by non-chemical weed control methods. Many of these tactics and methods have been investigated and demonstrated for use on field crops in Canada. However, herbicide use reduction is fundamentally dependent upon preventative strategies designed to create robust cropping systems that maintain low weed densities. Diverse crop rotation forms the basis of preventative strategies as it inherently varies cropping system conditions to avoid weed adaptation. There is evidence that residual weed densities resulting from herbicide use reduction are manageable within competitive cropping systems. A great deal of research has been done on herbicide use reduction on field crops in Canada, and most projects report definite possibilities for herbicide use reduction in field crop production in Canada. Synthesizing and extending this information and customizing it for use on individual farms remain challenges. Collaboration between researchers and farmers can help to build successful strategies for herbicide use reduction which reflect the context of modern farming, the will of farmers and the culture of technology adoption among farmers. Key words: Pesticide use reduction, low-input agriculture, integrated pest management, integrated weed management