Research Accomplishment Reports 2010

Weed Management Strategies for Sustainable Cropping Systems

L.J. Grabau
Department of Plant and Soil Sciences

 

Non-Technical Summary

Weed management is generally viewed as a major challenge in conventional, transitional and organic cropping systems. Control of weeds in agriculture costs the U.S. economy more than $15 billion annually, more than the cost of controlling insects and diseases combined. Although organic cropping systems are often highly profitable anyway, weed densities frequently boarder on or exceed tolerable levels, and surveys of organic growers and studies of organic farms indicate that weeds are a major production problem. Moreover, existing methods for controlling weeds on organic farms depend on excessive soil disturbance, resulting in loses in soil quality.

Currently, little research is directed toward the weed management needs of organic producers. New methods like organically certifiable herbicides and weed management with cover crops are needed. There is also a need to evaluate existing approaches like nutrient management for weed control and the mechanisms of cultivator action.

Conversations with growers indicate that fear of uncontrolled weeds is frequently a factor inhibiting adoption of organic practices. Development of new weed management methods and improvement of traditional methods will speed adoption of organic practices, thereby reducing use of both herbicides and other pesticides. This will improve environmental quality and reduce expenses for farmers. Better weed management options will also improve yield and profits, thereby strengthening local communities.

2010 Project Description

Presentations were made in 2010 to three primary groups: i) About 55 organic producers at a "Third Thursday" event at Kentucky State University in February, 2010, ii) About 200 undergraduate students on a field trip to the University of Kentucky's research farms in September, 2010, and iii) About 20 Amish and Mennonite farmers at a field day in Trigg County, Kentucky in October of 2010.

2010 Impact

As we collected our sixth year of data on this project, it became clear that effective weed management strategies could indeed be implemented under the constraints of the national organic standards of the USDA. Timely pre-planting tillage, well-managed cultivation, and inclusion of winter-hardy cover crops were all helpful steps in this management system.

2010 Publications

Derek Caskey, Laura Harris, and Larry Grabau. 2010. Comparison of tillage systems for organic soybean production. Abstract presented at Internship Forum of the Natural Resources and Environmental Science program, University of Kentucky.