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Emerald Ash Borer confirmed in Waukesha Co.

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MUKWONAGO — The Emerald Ash Borer had already made its presence known in 11 other Wisconsin counties. Waukesha County is the newest addition to the list after officials confirmed the beetle killed an ash tree in Mukwonago.

David Farina, an area arborist, found the dead tree along Highway 83 last week. He says the invasive pest is a serious threat to ash trees across the state.

“A lot of people have ash trees in their yard and about 10 percent of the native trees in Wisconsin is a species of ash,” he said, “This insect doesn’t leave ash trees behind, it kills them all.”

The Wisconsin Department of Agriculture, Trade and Consumer protection confirmed earlier this month it found evidence of the EAB in Walworth County. Farina says the Asian import is such a threat because it has nothing to fear.

“Like anything in nature, there’s a balance of nature and so the native ash borer has its own natural predators,” Farina said, “Emerald Ash Borer isn’t a native species; it came from a foreign country so it has no predators, no enemies.”

Tracking the beetle is not easy. There’s another ash tree just a few feet away from the dead one in Mukwonago that shows no signs of stress. Farina says the dry conditions are weakening trees, which makes the more vulnerable to the EAB.

“The tree was stressed, it was weak and the Emerald Ash Borer finds weak trees and will attack them,” he said.

Although people can’t completely vanquish the EAB, Farina says they can keep the bug in check.

“And that’s important because it’s possible nature will find a natural predator to counter-balance and attack the Emerald Ash Borer,” Farina said.

Farina says you can protect trees on your property and in your neighborhood by doing a couple different things. First, water the base of the tree. You can also spray the base with an insecticide called “Imidacloprid”.