Political ecology and the pesticide paradox: Markets, pesticide use, and human-environment relations in Costa Rican agriculture

This dissertation examines pesticide residues in the context of Caribbean Basin non-traditional agricultural exports (NTAEs) and the multiple geographic scales of pesticide intensities and market integration. It is based on the author's field studies in Northern Cartago and the Ujarras Valley, Costa Rica. Quantitative and qualitative methods were employed, including 148 farmer surveys and produce buyer interviews. Part 1 reformulates political ecology's chain of explanation. Export firms interpret pesticide residue regulations seriously and control their contract farmers' pesticide use through both advice and enforcement. Export farmers' pesticide use practices in relation to residues are far more cautious than the literature suggests. Export farmers typically select the less residual synthetic pyrethroids and maximize time between spraying and harvest. Farmers producing exclusively for the national market are also more cautious concerning pesticide residues than the literature suggests. However, since there is minimal enforcement and residual pesticides are more effective, some national market farmers use pesticides proscribed for export on a regular basis, especially methamidophos, likely resulting in dangerous residues. Part 2 explores the "pesticide paradox," which is the finding that export crops are generally less pesticide intensive than national market crops in the study site. The agro-environmental history of the area reveals that national market vegetables were pesticide intensive by the 1950s, decades before the start of export production. Comparisons of pesticide intensity on the same crop produced for the national and export markets show that four export crops (carrot, chayote, green bean, and squash) are less pesticide intensive, while one export crop (corn) is more pesticide intensive. Findings demonstrate that markets and variety-pest interactions codetermine pesticide intensity. A geographical perspective on pesticide intensity shows that it varies over short distances in mountain environments and is especially high in cloud forest areas. Resource-rich farmers who live in the cloud belt move production out of it to lower their costs. An ordinary least squares regression analysis of crop- and field-specific pesticide intensity shows the joint importance of agency, structure, and agroecology in determining pesticide intensity. The last chapter draws conclusions, explores lessons for geography and political ecology, and makes policy recommendations.