Submitted to: Western Society of Weed Science Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/9/2000
Publication Date: 3/9/2000
Citation: Trucco,, ., Wiles, L., Westra, P. 2000. Development of organic matter management zones for more efficient application of herbicides.. Western Society of Weed Science Meeting Proceedings. Interpretive Summary: None required
Technical Abstract: Soil pH, organic matter content and structure all influence herbicide efficacy. Traditional weed control systems consist of uniform herbicide treatments based on the average characteristics of the field. However, the efficacy of the selected herbicide may vary across a field due to the heterogeneity of soil features. Consequently, it could be beneficial to characterize soil features within a field into management zones for herbicide applications. The objective of this study was to evaluate whether varying herbicide rates based on organic matter (OM) affected weed control. A variable rate herbicide treatment was applied next to a uniform herbicide application in six strips in each of two fields in 1998 and 1999. Selected variable rates of Dual R II Magnum plus Atrazine were applied to specific OM management zones in each variable rate strip. The grower selected and applied the uniform herbicide treatment. For each of the variable or uniform strips, weed seedlings were examined at approximately 100 ft intervals along a transect. Weed seedlings were counted in an 18-cm band over 1.5 m of crop row when the crop was at the 2-leaf stage. Weed seedlings were adequately controlled in the uniform and variable rate strips. There were no significant differences in the efficacy of control for any one weed species at different herbicide rates within the variable treatments (P>0.4169). In addition, no significant differences (P=0.05) were found for weed counts between the uniform and variable treatments.