First Cases of Emerald Ash Borer Infestation Discovered in Milwaukee

Jul 13, 2012

It was not entirely “unexpected” news Friday when Milwaukee officials announced conclusively - the Emerald ash borer hit a cluster of trees on the northwest side.

Scientists first spotted the destructive green beetle in Detroit, Michigan in 2002.

One of several emerald ash borer infestations discovered on Milwaukee's northwest side.

Since 2008, the beetle has nibbled its way into 11 Wisconsin counties.

Milwaukee Forestry Manager David Sivyer says the city acted proactively. In 2009, workers began injecting large ash trees with chemicals to ward off the pest.

“The treatment is very effective and we’re trying to help residents to understand that there are effective treatments – it has to be done before the tree is infested – so we’re encouraged them to do something; they have to either prepare to remove and replace that tree, or plan to inject or treat it in some way to protect because Emerald ash borer will sweep through our city and every tree will eventually become infested, if not treated,” Sivyer says.

Ash trees make up 17 percent of the tree canopy in Milwaukee.

The invasive pest is responsible for the deaths of tens of millions of ash trees in eastern United States and Canada