The Minnesota Department of Agriculture (MDA) has confirmed the presence of emerald ash borer (EAB) in Watonwan County for the first time. There are now 38 counties in the state, including Watonwan, with EAB.
An employee with the University of Minnesota Extension contacted the MDA after suspecting a group of trees in the town of Butterfield was infested with EAB. MDA staff were able to find EAB larvae and collect samples. Federal identification confirmed EAB.
Emerald Ash Borer was first discovered in Minnesota in 2009. The insect 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, 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 Watonwan County, the MDA is enacting an emergency quarantine of the county, which limits the movement of firewood and ash material out of the area.
The MDA issues quarantines for all areas known to have EAB to reduce the risk of further spreading the tree-killing insect.