2018 Crop Protection Guide for Tree Fruits in Washington

Special Programs

Sunday, December 16, 2018

Grasshopper and Mormon Cricket Control

Grasshoppers and Mormon crickets are sporadic orchard pests. They may damage fruit, foliage and small wood. Young trees are particularly vulnerable.  These pests are usually noticed in orchards in late June through mid-August.  The best control procedure is to eliminate their potential sources.  This means spraying or baiting areas adjoining orchards where they develop.  Federally sponsored programs may be available for noncrop areas.  Contact your extension agent for details.

Many chemicals used routinely in orchards will kill grasshoppers and Mormon crickets.  However, when they are large enough to migrate into the orchards, the pests become more difficult to kill, and continue to migrate in after the spray is applied.  The best strategy is to control grasshoppers in the nymphal stages as they develop in areas adjacent to the orchard. Carbaryl baits at 1 pound active ingredient per acre or malathion ULV (aerial application) are suitable for these areas. Avoid use of carbaryl in orchards if possible because of toxicity to predatory mites.

Tree Fruit Research & Extension Center, 1100 N Western Ave, Washington State University, Wenatchee WA 98801, 509-663-8181, Contact Us