Emerald Ash Borer

The Emerald Ash Borer (EAB) has been confirmed in the City of North Mankato. Infested trees were discovered by the Minnesota Department of Agriculture (MDA) and City staff as part of a routine tree inspection.

The City of North Mankato is currently completing steps to mitigate the spread of the Emerald Ash Borer. This page includes information and resources for homeowners with ash trees on their property, rules and recommendations for residents, the City's 2019 Emerald Ash Borer (EAB) Management Plan, and an EAB presentation from the MN Department of Agriculture (Dec 2021).

What is it?

The Emerald Ash Borer (EAB) is an exotic beetle that is metallic green, about ½ inch long and attacks and kills ash trees. The larvae feed on the inner bark of these trees, destroying the tree’s ability to transport water and nutrients and killing the tree altogether.

How did it arrive in Nicollet County?

EAB was first discovered in southeastern Michigan near Detroit in the summer of 2002. It is believed that it arrived in the United States on solid wood packing material carried in cargo ships or airplanes originating in its native Asia. EAB was found in Minnesota on May 14, 2009, in the city of Saint Paul and has since spread throughout Minnesota. There are now 38 counties in the state with EAB, and the Minnesota Department of Agriculture (MDA) has confirmed it has been found in the City of North Mankato and in surrounding counties and cities, including the City of Mankato.

What are the City's next steps?

The City continues to work through our “Structured Removal Plan” of ash trees to slow the spread of EAB by reducing host trees. The Parks Department continues to inspect public and private properties, both on request and during routine inspections. Suspect trees are carefully analyzed using sampling mechanisms consistent with MDA guidelines that include visually looking at all parts of the tree, branch removal, and bark shaving with a drawknife.