Mid-Atlantic Apiculture Beekeeping Topic No. 4. Not all pesticides are equally hazardous to bees. Prevention of bee losses is a joint responsibility of the spray operator, grower, and beekeeper. It is fostered by mutual understanding and cooperation which includes the exchange of information before pesticides damaging to bees are used.
Pesticides work in two ways to reduce bee populations.
Many pesticides that are necessary in crop production are highly toxic to honey bees. Secondly, the use of herbicides reduces the acreages of attractive plants for the bees to forage on. Pesticide damage to colonies takes many forms. Bees may be poisoned when they feed on nectar or pollen contaminated with certain pesticides. They may also be poisoned when they fly through a cloud of pesticide dust or spray, or walk on the treated parts of a plant.