No More Coddling the Proverbial Worm in the Apple

The codling moth, the most destructive insect pest of apples and pears worldwide, is being controlled in the western U.S.--and with less pesticides. The key is a coordinated attack over areas covering up to 1,000 acres and with 35 growers participating. The main tactic: using the insect’s own sex drive to thwart its reproduction.

Previously growers relied mainly on pesticides. Now the principal tool is a synthetic sex pheromone, a chemical mimic of the female insect’s natural sex attractant. On fruit trees, growers hang tiny dispensers that emit the fake pheromone. It so confuses male moths that most never find a female for mating. The technology--mating disruption--was developed by scientists with USDA’s Agricultural Research Service.

With no controls, codling moths could destroy an estimated 80 percent of the Northwest’s apple crop and 50 percent of the pears. And one worm--the moth’s larval stage--is more than consumers want to find in fruit they buy.

The codling moth effort is an areawide integrated pest management (IPM) program. It is the first of two now underway, and ARS plans more to support USDA’s goal of having 75 percent of U.S. cropland under IPM by the year 2000. Some growers in the codling moth program reduced insecticide use by 70 percent. Others plan using no insecticide this summer, saving up to $150 per acre. Reduced pesticides also allow populations of the moths’ natural enemies to build and help keep them in check.

ARS’ cooperators are Washington State University, Oregon State University, University of California at Berkeley, Washington Tree Fruit Research Commission, farm advisors, Washington Apple Commission, and Winter Pear Control Committee. They continue to refine the areawide IPM program at 10 research sites in Washington, Oregon and California.

A feature story about the project appears in the May issue of ARS’ Agricultural Research magazine. The story also is on the World Wide Web.

Scientific contact: Carrol O. Calkins, USDA-ARS Yakima Agricultural Research Laboratory, Wapato, Wash., phone (509) 454-6565, fax (509) 454-5646, e-mail ccalkins@yarl.gov.