Follow these precautions to help protect bees from pesticide poisoning:
- Identify what species of bees are present at the site and learn the specific ways to protect them. Alkali bees, bumble bees, honey bees, leafcutter bees, and other bees vary in their biology, susceptibility to pesticides, and effectiveness in pollinating a particular crop. Methods for protecting bees and promoting pollination can differ depending on the crop and bee species.
- Use the UC IPM Bee Precaution Pesticide Ratings to compare and select pesticides with lower risks to bees, and to learn how to protect bees when using certain pesticides. Bee precaution ratings for pesticides mentioned in the Pest Management Guidelines are included directly in the tables under Pesticides and Natural Enemy Releases.
- At minimum, read labels carefully and follow the directions for use. Pay close attention to the Environmental Hazards and Pollinator Protection statements on the label and take care to apply pesticides at the appropriate time based on these statements. Be sure to follow any additional instructions in the crop-specific Directions for Use as well, as these can also pertain to pollinator protection.
- In addition to following the pesticide label, comply with any applicable state and local regulations. In California, you must notify beekeepers within 1 mile of the pesticide application site of any pesticide applications at least 48 hours in advance. Use the BeeWhere application to determine if managed bees are nearby and obtain contact information for the appropriate beekeepers.
- During prebloom, do not use an insecticide or miticide (acaricide) with a long residual time (extended-residual toxicity) or with systemic (translocated) activity. Avoid pesticides with cautions on the label that read "highly toxic to bees," "toxic to bees," "residual times," or "extended residual toxicity." Residual toxicity to bees varies greatly between pesticide products and can range from hours to a week or more.
- Avoid applying any pesticides to plants that are flowering, particularly insecticides and miticides. Also avoid pesticide drift to nearby blooming plants, including weeds.
- Do not tank mix insecticides or miticides with fungicides for application where plants are flowering, including weeds.
- Do not add adjuvants to fungicide applications during bloom or when there is high honey bee activity in the field unless the product label or pesticide regulations direct an adjuvant should be added.
- If a fungicide or herbicide application is warranted during bloom and allowed by the label and regulations, make the application between sunset and midnight when bees are not active. Be aware that unlike honey bees that return to a hive, some bees spend the night on plants or in soil at the site.
- Do not directly spray bees, beehives, or bee nesting sites with any pesticide. Ensure that the applicator turns off nozzles when near beehives or nesting sites or that hives or bee boxes are removed from the area before application.
- Either remove or cover water sources before spraying pesticide, or supply new, clean water after an application is made.
- Use best management practices for chemigation to prevent bee exposure to pesticide-contaminated water. Chemigation drips or puddles may attract water-collecting bees.
- Prevent the formation and movement of pesticide-contaminated dust when planting pesticide-treated seed or applying pesticide granules or pellets.
- Contact the county agricultural commissioner to learn how to protect bees and the requirements before applying pesticides.
- Use integrated pest management (IPM) to maintain healthy crops and minimize pesticide use.
- Learn what types of bees are present locally and how pollinator management can enhance crop production by contacting the local UC Cooperative Extension office and consulting the California website of the Pollinator Conservation Resource Center.
- See Protecting Natural Enemies and Pollinators for more guidance and precautions.
More Information
- Chemigation Safety Measures include avoidance of pesticide-contaminated drips and puddles, University of Minnesota Extension.
- Committed to Healthy Hives in the Field (PDF, 10.2 MB), The Almond Conference 2017.
- Forage Your Way to Better Honey Bee Health (PDF, 0.8 MB), Almond Board of California.
- Fungicides and Their Effects on Non-Target Organisms, Especially Honey Bees, pp. 6–9 in Fungicides, Bactericides, and Biologicals for Deciduous Tree Fruit, Nut, Strawberry, and Vine Crops in California (PDF, 2.9 MB), UC.
- How to Reduce Bee Poisoning from Pesticides (PDF, 12.6 MB), Pacific Northwest Extension.
- Insectary Plants as alternate sources of bee nutrition, UC IPM.
- Pollinator Conservation Resource Center, Xerces Society for Invertebrate Conservation.
- Protecting Bees and Other Pollinators from Pesticides, U.S. Environmental Protection Agency.
- Protect Pollinators: Read Pesticide Labels, North American Pollinator Protection Campaign.
Adapted from Honey Bee Best Management Practices (BMPs) for California's Almond Industry, Almond Board of California.
