Trap Cropping to Maximize Agricultural Yield: Balancing Land Allocation Trade-Offs Between Main Crop Production and Effective Pest Management

Abstract

Trap cropping is a pest management strategy where a grower plants an attractive “trap crop” alongside the primary crop to divert pests away from it. We propose a simple framework for optimizing the proportion of a grower's field or greenhouse allocated to a main crop and a trap crop to maximize agricultural yield. We implement this framework using a model of pest movement governed by trap crop attractiveness, the potential yield threatened by pests, and functional relationships between yield loss and pest density drawn from the literature. Focusing on a simple case, we consider highly mobile pests that move freely across a small field or greenhouse, or within a larger field arranged in a repetitive layout (e.g. rows of trap plants). These pests are assumed to choose plants based solely on their relative attractiveness. We find that allocating 5%–20% of the landscape to trap plants is typically required to maximize yield and achieve effective pest control in the absence of pesticides. For highly attractive trap plants, growers can devote less space because they are more effective; less attractive plants are ineffective even in large numbers. Intermediate attractiveness warrants the greatest investment in trap cropping. However, the results are illustrative rather than prescriptive and could be sensitive to ecological and economic factors not included here, such as pest mortality, reproduction, spatial layout of traps, and additional costs associated with trap cropping. Despite these important caveats, the framework offers a transparent and tractable approach for exploring trade-offs in pest management and can be extended to incorporate more complex pest behaviors, crop spatial configurations, and economic considerations.