Green Acres

How Farmers, Gardeners and Insecticide Applicators Can Reduce Risks of Honeybee Injury When Spraying for Grasshoppers

Because of the increase in grasshopper pests this year and last year, many folks are spraying insecticides to save their crops and landscapes. The following article comes from the University of Nebraska and is available at: https://bit.ly/3vQPhuz.

Do not treat fields in bloom. Be especially careful when treating crops, such as alfalfa, sunflowers and canola, which are highly attractive to bees. Insecticide labels carry warning statements about application during bloom. Always read and follow the label. Examine fields and field margins before spraying to determine if bees are foraging on flowering weeds. Milkweed, smartweed and dandelion are examples of common weeds that are highly attractive to honeybees. Where feasible, eliminate blooming weeds by mowing or tillage prior to insecticide application. While bright and colorful flowers are highly attractive to bees, some plants with inconspicuous blossoms such as dock, lambsquarter and ragweed also are visited. When examining areas for blooming plants, consider all blooming plants. It is also important to be aware that many plants only offer pollen and nectar for a few hours each day. Fields should be scouted for bees at the same time of day as the anticipated insecticide application. Choose short residual products and low hazard formulations.

Avoid spray drift. Give careful attention to the position of blooming crops and weeds relative to wind speed and direction. Changing spray nozzles or reducing pressure can increase droplet size and reduce spray drift. Apply insecticides when

bees are not foraging. Some insecticides can be applied in late evening or early morning (i.e. from 8 p.m. to 6 a.m.) with relative safety.

Adjust spray programs in relation to weather conditions. Reconsider the timing of insecticide application if unusually low temperatures are expected that night. Cool temperatures can delay the degradation process and cause residues to remain toxic to bees the following day. Stop applications when temperatures rise and bees re-enter the field in early morning. Contact local beekeepers and obtain locations of bee yards. Honeybee injury results when pesticides are applied or allowed to drift to blooming crops, wild plants or weeds. Almost all accidental injury can be avoided by taking precautions to avoid pesticide application or drift to blooming plants.

Many pesticide applications pose minimal risk to bees, and beekeepers may choose to accept some risk rather than move colonies. Notify beekeepers as far in advance as possible. Read the pesticide label. Carefully follow listed precautions with regard to bee safety. Maintain bee forage areas. Intensive agriculture often increases bee dependence on cultivated crops for forage. Encouraging bee forage plants in wild or uncultivated areas will reduce bee dependence on crop plants that may require pesticide treatments. Plants recommended for uncultivated areas include sweet clover, alfalfa, purple vetch and birdsfoot trefoil. Most trees and shrubs are beneficial to bees. Soil conservation, natural resource and game managers usually are eager to help establish plantings that benefit bees. These areas also conserve soil and provide valuable habitat for plant and wildlife conservation programs.

Montana State University, U.S. Department of Agriculture and Montana Counties Cooperating. MSU Extension is an equal opportunity/affirmative action provider of educational outreach.