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Beware of the Emerald Ash Borer

Residents need to beware of a little bug named the Emerald Ash Borer. This pesky little beetle is capable of decimating ash populations wherever it pops up. Although the Borer has not been found in Illinois, it was discovered for the first time in North America , feeding on ash trees in southeastern Michigan. The beetle’s natural habitat is eastern Russia, northern China, Japan, and Korea.

All species of North American Ash appear to be susceptible to invasion. If detection of the Borer is not caught in the early stages, and infestation is high, the ash tree will not recover and will die. However, if the beetle is detected early, pesticide application, although not a guaranteed cure, may improve the ash tree’s chance of survival.

The Emerald Ash Borer is bright green in color and approximately 1/2 inch long by 1/8 inch wide. To view a picture of the Emerald Ash Borer you can access the Village’s web site at

When invasion occurs, the Borer penetrates the bark, attacking the area known as the xylem, which is the water and nutrient conducting tissue in trees. Once an ash becomes heavily infested, canopy dieback will occur, which will usually start at the top of the tree. After initial infestation, 1/2 of the canopy will die in the first year. All of the canopy will be dead within two years of infestation.

There are a couple of signs to look for to see if your ash tree might have the Emerald Ash Borer. Investigate the base of your ash tree. Although difficult to see, the adult beetles leave a “D” shape exit hole in the bark, roughly 1/8 inch in diameter. The beetles emerge in June, so keep a close eye out in the early summer. Also, you will notice rapid decline in an infected ash tree between July and October, during which larval feeding is most active, so contact a professional arborist.

If anyone has reason to believe that their ash tree might have Emerald Ash Borer contact the Village or the Illinois Department of Agriculture for further investigation.