Abstract: Organic agriculture is often suggested as a means to improve agricultural sustainability through less intensive and more natural production methods. Yet, the environmental impacts of organic production practices are only partially understood and whether such production practices have spillover impacts on surrounding producers remains unknown. Using approximately 9,000 organic and 83,000 conventional field-year observations in Kern County, CA from 2013-2019, we sought to identify the impact of organic production on pesticide use, particularly pesticide use stemming from potential spillovers to surrounding organic and conventional fields. We conduct a series of panel data models to evaluate how nearby organic agriculture drives different types of pesticide use (overall, insecticide, herbicide, fungicide) after controlling for region-, crop-, farmer- and year-specific characteristics. We find surrounding organic agriculture generally leads to a decrease in pesticide use on organic fields, which appears mostly driven by the reduction of insecticides and fungicides. In contrast, surrounding organic agriculture leads to either a small, but significant increase for these same pesticide types on conventional fields. Our results suggest organic producers tend to benefit from nearby organic fields, possibly indicating a concentration of organic fields contributes to a landscape of pest control benefits for fields relying on non-synthetic pesticides and ecological pest control. Conventional fields, on the other hand, tend to have a small increase in pesticide use as the area of organic production nearby increases, which could suggest organic fields generate both additional pests and biocontrol agents that spillover, with conventional fields realizing the costs (pests) more than the benefits (biocontrol).
