Ash Trees and the Emerald Ash Borer


Potentially one of the most destructive alien pests ever introduced in the United States. First discovered in southeastern Michigan in 2002, EAB has rapidly spread across the Midwest, killing millions of ash trees. The first infestations in Illinois were discovered in rural Kane County in 2006 and moved across Chicagoland afterward. The Village’s first confirmed infestations were found on Mayfair Drive in summer 2010.

EAB could eventually spread throughout the entire Village and kill ash trees that are not treated or removed. This is particularly troubling due to the large number of ash trees on both public and private property. The Village is currently implementing a management plan to respond to this threat and would like to encourage residents to assist. This website has been compiled to help you better understand what EAB is, to help you consider your options in addressing it on your property and to update you on the Village’s actions and responses to this threat. EAB is a wood-boring beetle from Asia that feeds on ash trees. Adult beetles are metallic green and about ½ inch long. Once introduced into an area, the adult beetles lay eggs in ash trees. The larvae bore into the tree and literally strangle it by damaging the tree’s vascular system, or the main circulatory system of the tree. Within two to three years, the tree dies and becomes brittle. If the tree is not removed at this point, it could become a public safety hazard.
While there are several different ash species, they share some common characteristics. Ash leaves are perhaps the easiest way to identify if a tree is an ash. These leaves will have 5-11 smaller leaflets attached that grow directly across from each other and are either smooth or have very fine "teeth." Aside from these leaves, older ash trees will have a distinctive diamond-shaped bark while younger trees will have a smooth bark surface. Finally, ash trees have dry, oar-shaped seeds that hang in clusters from the tree until falling in late fall. More information on identifying ash trees can be found in the following article "Distinguishing Ash from Other Common Trees."

Why Should I be concerned?

EAB is particularly concerning due to the sheer number of ash trees in the Village. Ash is native to Illinois and was popular for a number of years as a shade tree for both public parkways and private property. In addition to the thousands of known ash trees in Village’s parkways, there are likely thousands more on private property. If you take no action, the tree will likely die and could cause property damage if not removed.

What is the Village doing to address the threat?

The Emerald Ash Borer (EAB) has been positively identified by the Illinois Department of Agriculture within the Village of Libertyville. As a result the Village has adopted an EAB Management Plan, which includes ongoing monitoring of Ash trees in the Village, removal of infected trees, proactive chemical treatment of parkway Ash trees which have not yet shown the symptoms of EAB, public education, and an enforcement program for the removal of Ash trees on private property which have been identified as infected with the EAB. Please contact the Village Public Works Department at 847-918-2074 for additional information or assistance with identification of EAB.

What can I do to address the problem?

At this time, property owners have two options: outright removal or treatment of their trees. Certain insecticides have proven to be effective in treating or preventing infestation if the damage to the tree is not too extensive. Contact an International Society of Arboriculture (ISA) certified arborist to see what options you have for treatment. A list of certified arborists or local landscaper can be found at this web address:

Please note that treatment, depending on the insecticide used, may be effective for one or two years and then will need to be reapplied and will be a long-term commitment. Thus treatment may be more. Further, if your tree does die, the Village may require you to remove it in order to protect the public.

If you are having a tree removed, make sure that your contractor has signed an EAB compliance agreement with the State of Illinois Department of Agriculture. This agreement outlines how to handle infested wood to slow the spread of EAB.

What can I do to help?

EAB is not a naturally fast moving pest (about ½ mile per year) but has been able to spread through the movement of infested firewood. Please do not move ash firewood. Further, please ensure that any contractor you hire to remove or treat your tree has signed the EAB Compliance Agreement with the State of Illinois Department of Agriculture, as discussed above.
Identifying Ash Leaves-2
EAB life cycle-2