Official website for the City of Aurora, Illinois. Mayor Robert J. O'Connor

Emerald Ash Borer Emerald Ash Borer - Adult

The Emerald Ash Borer (EAB) insect is an exotic woodborer that was found to be attacking and killing ash trees in Michigan in 2002. The Emerald Ash Borer attacks only ash trees and is a devastating and destructive pest that greatly affects the urban forest. EAB is easily spread through the movement of firewood, logs and nursery stock.
Since its detection, EAB has killed millions of ash trees and has spread into Indiana, Ohio, Illinois, Wisconsin, Iowa and other states. Discovered in Illinois in 2006, EAB has since spread throughout northeast Illinois into the nearby towns of Geneva, Batavia, North Aurora and Naperville as well as other locations statewide.
The first confirmation of EAB in Aurora was found in a “trap” tree located on the city right-of-way on Liberty Street just west of Route 59 in Du Page County in 2008. Since this initial confirmation, the EAB has spread throughout the City.

Homeowners should prepare for the arrival of EAB within their own yards.

Homeowners should periodically examine their trees for any signs of an EAB infestation –i.e. sprouting near base of tree, woodpecker holes are present, bark splitting and D shaped holes.

The City’s response to EAB since it has been discovered in Aurora:

Aurora has adopted a two-part ash tree removal strategy on city-owned property as a management plan to help mitigate and control the spread of EAB. Ash tree removal has been the preferred strategy used by the majority of communities with confirmed EAB infestation.

Part I: Newer Subdivisions
Aurora crews are currently working from subdivision to subdivision, clear cutting all ash trees. A notice is placed on the ash trees one week prior to removal to inform the homeowner of the scheduled work to be performed.

Part II: All other areas of the City
Ash trees that exhibit signs of EAB infestation will be removed along with any other nearby ash trees on the same block. At this time, the City will not be removing healthy ash trees unless requested by the homeowner.

If in the opinion of the City’s arborist the tree is not considered a hazard, homeowners whose trees are being chemically treated can request the tree not be removed.

Please contact the Street Division if you have any questions or concerns at 630-256-3680.


Check for periodic updates at these Web sites:

Insecticide Options for treating Ash Trees

Chemical treatment options do exist but have not been proven to be 100% effective. Consult a professional Arborist for information. This PDF bulletin is designed to answer frequently asked questions and provide the most current information on insecticide options for controlling Emerald Ash Borers.

Insecticide Options PDF

Signs to Look for

Ash leaves

Ash Leaves

Ash leaves are somewhat unique since they have several green leaflets per leaf stem, usually seven. The leaflets are located directly across from each other with one at the end.

Emerald Ash Borer

Emerald Ash Borer

The Emerald Ash Borer is an exotic beetle from Asia. Though small (approximately 1/2 an inch), it can fly up to a mile from where it emerges.

D-shaped exit holes

D-Shaped Exit Holes

D-shaped exit holes can be found on trees where the adult beetles emerged. A tree with these holes has been infested for at least one year. They will be present on the branches and the trunk.



“Suckers,” or new sprouts, may develop around the bottom of the main trunk of an infested tree. They can grow until they are 2-3 inches in diameter and are again attacked by the Emerald Ash Borer.

Tree Canopy

Tree Canopy

Tree canopy will begin thinning and branches will die. First there will be yellowing of the leaves, then dead branches. The thinning will begin at the top third of the tree, then spread over time. Usually, a tree will live two to four years after thinning at the top of the tree occurs.