Pesticide drift into field margins threatens bee pollinators and other beneficial insects

Authors: Graham, Kelsey; SANCHEZ, ANGELICA - Cornell University; MCART, SCOTT - Cornell University; ISAACS, RUFUS - Michigan State University

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/10/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Pesticide drift is when applied pesticides move away from the target crop and deposit in non-target habitat. This is a major concern in agricultural landscapes and can have detrimental impacts on beneficial insects, including pollinators. One way to reduce the impact of pesticide drift is to increase the distance between the crop and sensitive habitats such as wetlands or wildflower plantings used for conservation purposes. The aim of this study was to determine the optimal distance, or buffer zone, between the crop and wildflower plantings used to provide flower and nesting habitat to pollinators on northern highbush blueberry farms in Michigan. To measure pesticide drift, we used silicone wristbands placed at set distances away from the crop (0m, 2m, 4m, 8m, 16m, 24m, 32m) and then extracted and quantified the pesticides deposited on the wristbands. We found that there was no decline in pesticide deposition as you moved away from the crop until 32m was reached. Given that most wildflower plantings on farms in this region are within 32m of the crop, other drift reduction measures beyond buffer zones, such as installation of windbreaks and use of drift reduction technologies such as special spray nozzles, are recommended to minimize the impacts of drift.

Technical Abstract: Pesticide drift into sensitive habitat is a major concern in agricultural landscapes and can have negative impacts on non-target animals including wild bees and other beneficial insects. Creating buffer zones between the crop and sensitive habitats has therefore been commonly proposed as a mitigation measure for reducing off-target pesticide deposition. Given prior evidence of significant pesticide deposition in wildflower plantings adjacent to highbush blueberry farms in Michigan, the aim of this study was to determine the buffer zone size needed to significantly reduce pesticide deposition in these plantings. We used silicone wristbands as passive pesticide samplers placed at varying distances away from the crop (0m, 2m, 4m, 8m, 16m, 24m, 32m) at 15 conventionally managed blueberry farms during the fruit ripening period when insecticide applications are common. We found that there was no significant reduction in pesticide deposition until 32 m was reached, and there was no significant reduction in insecticide deposition at any of the tested distances. Therefore, other drift reduction measures beyond buffer zones, such as installation of windbreaks and use of drift reduction technologies (DRT spray nozzles) is recommended.