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Emerald Ash Borer
Village Residents who are interested are invited to participate in the treatment program for a bulk-rate savings

The Emerald Ash Borer (EAB) is an invasive wood boring beetle, native to eastern Asia. First discovered in North America near Detroit, Michigan in 2002, it has spread to several eastern and mid-western states, including Wisconsin. While not a threat to human health, the Emerald Ash Borer does threaten our forest and urban tree population. It is 100% fatal to native ash trees regardless of size, age or state of health.

The larva of the Emerald Ash Borer spends its life inside an ash tree feeding on the inner bark where it cannot be seen. This feeding disrupts the tree’s ability to transport water and nutrients, causing the tree to starve and eventually die. An ash tree infested by the Emerald Ash Borer can die within two to four years. It is estimated that more than 50 million ash trees are dead or dying throughout the Midwest because of this insect. An Emerald Ash Borer was found in Kenosha County in a state trap at Highways 31 and 50 last August.

To know if you could be impacted by the Emerald Ash Borer, it is important for you to know how to identify both the tree and the presence of the pest. Ash trees should be leafing out at this time of year. Look for the opposite branching pattern - two branches coming off of a main stem, one on each side, directly opposite each other. Ashes have many small dots (vascular bundles) on their leaf scars, forming a semi-circle or crescent pattern. Buds and leaf scars are opposite one another on twigs. White and green ashes have thick, diamond-patterned bark, while black ash bark is thin, ashy-gray and scaly. If leaves are present, they will appear as compound leaves with 5-11 leaflets. (See photo above)

There are a number of indicators of an Emerald Ash Borer infestation. To determine the presence of the Emerald Ash Borer in your ash tree, look for a combination of at least two or more of the following symptoms or signs:

• excessive sucker growth at the base of the tree trunk (stressed trees will attempt to grow new branches and leaves where they are still able)
• vertical splits in the bark (larvae can often be seen beneath bark splits)
• woodpecker feeding (typically evident higher in the tree where the Emerald Ash Borer prefers to attack first - damage will look like strips of bark have been pulled off of the tree)
• D-shaped emergence holes (as adults emerge from under the bark, they create D-shaped holes that are approximately 1/8 inch in diameter)
• S-shaped fissures under the bark (as larvae feed under the bark, they wind back and forth in a serpentine pattern)
• the presence of cream-colored, slightly flattened larvae and the metallic green insect itself

There are two types of preventative treatment options available based on the diameter of the tree trunk at waist height. Ash trees with a trunk diameter of four inches or less are treated through soil injection. Soil injection is performed two times per year, once in the spring and once in the fall. Ash trees with a trunk diameter of five inches or more are treated through direct injection into the tree trunk. This treatment is performed every two years.

Because it is more cost effective to treat the problem than it would be to remove and replace trees after they have died, the Village will begin a treatment program this spring. The Village will contract with a specialist to begin treatment of up to 1,100 ash trees within the public right of way. The public right of way is the area 15 feet behind the curb in subdivisions and approximately five feet behind the ditch in rural areas.

Village staff has asked the contractors bidding on the work to extend the same bulk rate (that the Village will pay for the treatment of ash trees) to residents for the treatment of ash trees that are on their own property and outside of the Village right of way. If you are interested in participating in the program, please click View PDF below.

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