Balancing economy and ecology: A systems comparison of leading organic weed management strategies

View the project final report

• 2014 annual report
• 2015 annual report

Commodities

• Vegetables: cucurbits, garlic, onions, peppers, tomatoes

Practices

• Crop Production: conservation tillage
• Education and Training: decision support system, display, extension, farmer to farmer, focus group
• Farm Business Management: budgets/cost and returns, risk management, whole farm planning
• Natural Resources/Environment: biodiversity, soil stabilization
• Pest Management: biological control, competition, cultural control, economic threshold, eradication, integrated pest management, mulching - vegetative, mulching - plastic, physical control, prevention, soil solarization, weed ecology
• Production Systems: organic agriculture
• Soil Management: nutrient mineralization, organic matter, soil chemistry, soil microbiology, soil quality/health
• Sustainable Communities: analysis of personal/family life, social capital, sustainability measures

Many organic farmers manage an increasing weed problem with more equipment, additional cultivation events, and supplemental hand weeding. On the other hand, “Seedbank Managers” have a longer-term perspective, recognizing that a decreasing weed seedbank results in fewer weed seedlings, and decreasing investments in hand weeding to achieve nearly weed-free crops. A third strategy, exemplified by “Intensive Mulchers” aims to solve weed problems with an early-season investment of mulching labor to provide season-long weed control. Due to the fundamentally different economic and ecological implications of each of these weed control systems, new growers may be unsure of which strategy to adopt and there are very few studies that have compared the strategies, especially for crops other than tomatoes. In this project we will evaluate these contrasting weed management systems in field experiments with the general hypothesis that successful weed control can be achieved by each of these three strategies, but with varying long-term implications for economic performance, weed seedbanks, and soil quality implications. The resulting benefits and drawbacks of each strategy will inform a modeling effort to create a decision aid in which farmers will have the ability to input their farm resources and management goals in order to determine the strategy that best suits their interests. While the project results will benefit all vegetable farmers, new organic diversified vegetable farmers have the most to gain as they develop their own weed management philosophies.

1. 1. Investigate the hypothesis that four weed control systems (critical weed free period control, zero seed rain, plastic mulch, and organic mulch) have varying short- and long-term effects on yield, soil quality, weed/pest suppression, and profitability.

1. 1. Determine the factors that motivate farmers to adopt these contrasting weed management strategies.

1. 1. Develop a decision aid that determines the optimum weed control strategy based on a farmer’s current resources and management goals.

1. 1. Publicize our results through presentations, publications, and extension events so that 100 New England farmers benefit by using our decision aid to inform their management strategy.