RESEARCH ARTICLES/INFORMATION

Research Category: Soybean Agronomy Year: 2004 Researcher: Al Hamill Susan Weaver Institution: AAFC Topic: Long-term effects of herbicide reduction (optimization) strategies in field crop rotations Funding: $10,000 Research Details: Executive Summary: This project is intended to benefit the industry through an improved understanding of the long-term effects of different weed management strategies in field crop rotations. These strategies include standard herbicide treatments intended to achieve excellent weed control, reduced rates of these standard treatments (75 to 25% of the labelled rate), and treatments based on economic thresholds for weed seedlings or seed bank densities. The cumulative effects of these different strategies, applied to the same plots over time, are being assessed in a corn-soybean and a corn-soybean-winter wheat rotation at two locations in Essex and Kent Counties. The assessment includes an analysis of the effects of the different weed management strategies on weed population trends, crop yields, and net returns to the grower. It is too early to draw conclusions about profitability, but in the first two years of the study, targeted reductions in herbicide use have not resulted in increased weed populations or reduced crop yield, except in the untreated controls. File: