Emerald ash borer located in Freeborn County

The Minnesota Department of Agriculture has confirmed emerald ash borer in Freeborn County for the first time. There are now 28 counties in the state with EAB.

A contractor for a local electric cooperative was doing tree maintenance along utility lines near the city of Alden when they noticed ash trees with signs of EAB. The contractor contacted the MDA through the department’s Arrest the Pest line, and MDA staff were able to find live EAB larvae and collect samples for federal identification.

Emerald ash borer larvae kill ash trees by tunneling under the bark and feeding on the part of the tree that moves nutrients up and down the trunk. Often, the trees show several signs of infestation because of this. Woodpeckers like to feed on EAB larvae and woodpecker holes may indicate the presence of emerald ash borer. Also, the EAB tunneling can cause the bark to split open, revealing characteristic S-shaped galleries underneath.

Because this is the first time EAB has been identified in Freeborn County, the Minnesota Department of Agriculture is enacting an emergency quarantine to limit the movement of firewood and ash material out of the county. The MDA issues quarantines for all counties known to have EAB to reduce the risk of further spreading the tree-killing insect.

Two virtual open houses for residents and tree care professionals in the county will be held on Wednesday, August 11. Experts from the MDA will give a brief presentation followed by a question-and-answer session.