In July 2014, the Minnesota Department of Agriculture (MDA) published a series of best management practices (BMPs) for agricultural insecticides (link to BMPs). These BMPs were created in response to seasonal detections of chlorpyrifos in several rivers and streams in the agricultural areas of Minnesota from 2010 to 2012. Subsequently, MDA determined chlorpyrifos to be a "surface water pesticide of concern" which initiates BMP development. Some MDA samples had concentrations violating water quality standards established by the Minnesota Pollution Control Agency (MPCA) to protect aquatic life, which led the MPCA to list three water bodies as impaired due to chlorpyrifos.
One set of BMPs focuses specifically on chlorpyrifos and the other set of BMPs is for all agricultural insecticides. Chlorpyrifos is an organophosphate insecticide with broad-spectrum activity that is used for management of pests in various agricultural crops. Chlorpyrifos is an active ingredient in various products, including but not limited to Lorsban, Cobalt, Dursban, Nufos and Yuma.
The BMPs help users follow mandatory label requirements and provide integrated pest management (IPM) recommendations to reduce insecticide input. Label use requirements & setbacks are legally enforceable. Recommendations not included on insecticide labels are voluntary. However, if the BMPs prove ineffective at decreasing violations of MPCA standards in surface waters, mandatory restrictions on use and practices may be required by MDA.
The BMPs for use of chlorpyrifos were designed to be used in conjunction with the BMPs for all agricultural insecticides (use IPM, follow label directions, reduce drift, etc.). Here, is a summary of chlorpyrifos BMPs, but I encourage you to review the full content of both sets of BMPs.
- Use lowest label rate which will effectively control pest
- Apply product according to label
- Maintain legally required application setbacks from permanent water bodies (check individual labels) (ground boom=25 ft; orchard airblast=50 ft; aerial [plane/helicopter]=150 ft)
- Utilize IPM
- Rotate insecticides
- Manage and dispose of unused product properly