Pesticide Notification

When is pesticide notification required?

Beekeepers with apiaries located near or within agricultural land may opt to receive notice of pesticide applications that are toxic to bees. The notification is required when these pesticides are applied to blossoming crops within a mile radius of the registered apiary. If the pesticide will be applied to a blooming crop, the applicator is required to notify the beekeeper 48 hours in advance prior to beginning the application.

Pesticides that are “toxic to bees” are determined by checking the Environmental Hazards section of the label. An example of this section is shown below:

Pesticide label "Environmental Hazards" box

Contra Costa County encourages pesticide applicators to utilize the University of California Integrated Pest Management (UC IPM) guidelines to further mitigate bee risk to pesticide exposure and protect brood development.  

How does pesticide notification work?

To prevent accidental pesticide poisoning, it is important for all parties to communicate and fulfill their responsibilities in the notification process.

Beekeeper responsibilities

Beekeepers are responsible for registering their colonies with their local County Agricultural Commissioner’s office on January 1st of each calendar year. Online registration is available using the California Department of Agriculture (CDFA) BeeWhere website. During registration, apiarists can specify a preferred contact method and best available time to receive notification.

After registering, beekeepers must keep colony locations current and up-to-date on the BeeWhere database using the GIS mapping tool.  Locations that do not have bees must be zeroed out until bees return or deleted if bees will not return. 

Beekeepers should determine appropriate action upon receiving notice of pesticide applications and share any concerns or questions with the applicator. Following the pesticide application, apiarists should monitor for bee kills and immediately report any issues to the Contra Costa County Agriculture Department.

Applicator responsibilities

Each year, property operators producing an agricultural commodity are required to obtain an Operator Identification Number (OIN) or Restricted Materials Permit (RMP) prior to applying pesticides.  The Applicator Guide for Notification to Beekeepers, which goes over the responsibilities of pesticide applicators, is included with OIN/RMPs and agricultural pest control business registrations when operators and businesses apply pesticides to flowering plants.


Applicator Guide for Notification to Beekeepers (PDF)

BeeWhere website

California Department of Food and Agriculture (CDFA) pollinator protection

UC IPM bee precaution pesticide ratings

US Environmental Protection Agency pollinator protection