Agroecological Pest Management Strategies at D-Town Farm

Abstract

This project partnered with the Detroit Black Community Food Security Network to test pest management methods that are safe for both people and the environment. We conducted plotscale experiments at D-town farm to determine which organic, agroecological methods are most effective at deterring caterpillars and aphids from brassica species. The experiment was implemented in kale and collard green crops on the farm. The pest management strategies tested included a weekly application of a neem oil-dilution, and a physical exclusion barrier in the form of a net that covered the crop rows, both compared to a control with no pest management. Our response variables included 1) abundance of aphids, 2) abundance of caterpillars, 3) percentage of leaves per plant with damage due to herbivory, 4) and percentage of leaf lost due to herbivory. We observed an increase in aphid abundance across both crop types in the net treatment, but this effect was only significant in the kale. Caterpillar abundance did not show any significant difference among treatments but tended to be lower in the net treatment for both crops. The percentage of leaves with damage from herbivory was significantly lower in the net treatment in both crops and in the neem treatment in the kale. However, percentage leaf loss was significantly greater in the net treatment for both kale and collard greens. In summary, our findings show that while the net treatment reduced damage from herbivory as well as caterpillar abundance in kale and collard greens, it caused the aphid population to grow. The neem treatment reduced caterpillar abundance and damage from herbivory in kale, but not in collard greens. Further experimentation is needed to find a pest management approach that is feasible and effective for reducing both aphids and caterpillar pests in brassica crops at D-town Farm.