Emerald ash borer was found on September 12, 2005, in Brimley State Park in the Upper Peninsula of Michigan. This state park is near Sault Ste. Marie, Ontario. Two larvae were found in one of nine detection ash trees placed in the park. This represents the first detection of this beetle in the Upper Peninsula.

Girdled trees and boles for beetle detection have also been located in various areas of Illinois. Those in northeastern Illinois are monitored by Morton Arboretum staff, whereas the rest are monitored by Jim Appleby of the University of Illinois. No emerald ash borers have been found in Illinois.

The closest known location of emerald ash borer is in St. Joseph, Michigan, which is currently the location of an emerald ash borer eradication effort. St. Joseph is just south of Benton Harbor and is only 70 miles around the lower shore of Lake Michigan from Illinois. Remain vigilant for this pest and let us or the Illinois Department of Agriculture know if you see signs of this insect.