Washington State apple farmers who have relied on chemical pesticides in the past to control harmful pests are getting help with a new non-toxic approach to pest control called mating disruption. By reducing the use of broad spectrum insecticides, farmers can improve the biological control of other orchard pests and reduce the risk to farm families and orchard employees from the use of chemical pesticides.
A new report by the Natural Resources Defense Council, released last week, concludes that children living on or near farms are more likely to be exposed to harmful pesticides. Insect mating disruption promises to enable farmers to produce cleaner food for less cost, with fewer of the direct risks associated with spraying pesticides.
Growers favor the new method because it can be less expensive than relying exclusively upon chemical pesticides, poses fewer risks to farm families and orchard employees, and is less harmful to wildlife and other beneficial insects around the orchard. Washington State University Cooperative Extension Integrated Pest Management specialist Ted Alway believes that mating disruption is likely to be a key tool for most apple and pear growers in the state.
Mating disruption involves confusing harmful insects so they don’t reproduce. Alway coordinates the Codling Moth Areawide Management Program, a cooperative program involving WSU, the U.S. Department of Agriculture and other agencies.
“Many insects, including codling moths, use sex pheromones (or chemical secretions) for locating their mates,” Alway said. Codling moths are the only pest in Washington state that must feed on the apple fruit. With mating disruption, small hanging strips containing a synthetic sex pheromone are placed in the orchard trees. When the dispensers release the chemical substance, male moths become disoriented, have less success finding the female, and as a result, fewer fertile eggs are laid.
Although initially slow to catch on, mating disruption for codling moths is now used on close to 40,000 acres of Washington orchards in 1998, out of a total of about 160,000 acres of bearing apple trees in the state, Alway said. Twenty to twenty-five percent of the apple acreage in Washington is now being treated with mating disruption.
The Codling Moth Areawide Management Program was established in 1993 when WSU and USDA scientists selected the codling moth as the prime target for an areawide pest management program.