Beekeepers have had it tough lately, with colony collapse disorder now added to their other challenges of varroa and tracheal mites, brood diseases, and small hive beetle. Growers can take the following steps to help protect bees from pesticide exposure:
1. Don’t apply insecticides during bloom when bees are actively foraging. Time sprays during the bud stage or after petals have dropped. Carbaryl used as a blossom thinner can be hazardous to bees.
2. Move hives before spraying or cover with wet burlap prior to spraying, keeping hives covered for two to three days. Don’t use plastic sheeting as it can result in overheating.
3. Place hives on hilltops to avoid chemical drift.
4. If using high toxicity pesticides, keep bees out of the orchard for 48 to 72 hours after spraying. Follow label requirements, including restrictions that protect bees. Unusually low temperatures can increase the time that toxic residue remains on the crop.
5. Apply pesticides when bees are not flying. Bees are most active from 8 a.m. to 5 p.m. and when temperatures are above 55°F.
6. Always check the orchard for bee activity before applying pesticides.
7. Remove attractive blooms, such dandelions, before treating the orchard with pesticides.
8. Don’t contaminate standing water with pesticides or drain the spray tank onto the ground, creating puddles. Bees will consume and bring back contaminated water to the hive.
9. Use less toxic compounds and formulations. Granular formulations are the least hazardous, microencapsulated insecticides are the most toxic formulation. Dusts and wettable powders tend to be more hazardous than solutions or emulsifiable concentrates.
10. Don’t use systemic pesticides before bloom.
SOURCE: Dr. David Epstein, Michigan State University