Gypsy moth eggs are hatching in northern Illinois, so it will soon be time to control these insects in Lake County and other areas in northeastern Illinois where the “Slow the Spread” program conducted by the USDA–APHIS and Illinois Department of Agriculture is not treating. Spraying will probably occur during the third or fourth week of May, followed by another application one week later. For updates on Slow the Spread treatments, times, and locations, as well as other gypsy moth information, refer to http://www.urbanext.uiuc.edu/gypsymoth/default.cfm. Insecticides recommended for larval control are Bacillus thuringiensis kurstaki (Dipel, Thuricide), spinosad (Conserve), tebufenozide (Mimic), and cyfluthrin (Tempo).
Emerald ash borer has recently been found in Indiana; however, its location is in Steuben County, the most northeastern Indiana county. This is about 140 miles from Illinois. Of perhaps more concern is its detection in St. Joseph, Michigan, which is about 70 miles from Illinois. Continue to be vigilant for ash trees dying from the top down with 1/8-inch diameter, D-shaped emergence holes in the bark. Emerald ash borer emergence occurs in early June, so holes appear at that time. If you locate suspicious trees, contact your local Extension office or the Illinois Department of Agriculture, (800)641-3934.