| Predaceous and parasitic insects provide control of important citrus pests. However, many pesticides are toxic to these beneficials. Using California citrus grower survey data, this article tests whether landscape-level use of pesticides affects the presence of and reliance on Aphytis melinus, an important beneficial insect. Results show that landscape-level pesticide use decreases the presence of A. melinus and increases reliance on insecticides. Pesticide use on non-citrus crops has a significant negative effect on the presence of Aphytis melinus, suggesting a cross-crop spatial externality. Our findings illustrate that regulations designed to address cross-crop effects on beneficial insects can increase social welfare. |
