Emerald Ash Borer

EAB is a serious invasive tree pest, and consequently, is regulated in an effort to slow the spread of the insect to areas not yet impacted.

  1. Treatment

The City of Owatonna is proactively treating ash trees for Emerald Ash Borer (EAB). EAB has been identified in Steele County, resulting in a quarantine of Steele County. The effort by the City of Owatonna is expected to delay the spread of EAB. There are approximately 1,200 boulevard ash trees, and the City intends to treat approximately 1/3 each year, resulting in a three-year treatment rotation. The treatment of the boulevard trees benefits private trees as well. As the bugs travel from tree to tree, they die when they eat from treated tree. Not all trees need to be treated for the program to be effective.

Treatment Process: The Street Department begins by measuring the diameter of the tree to determine how much product and how many injection needles are necessary for the treatment. Then holes are drilled, and needles are inserted into the tree, this pressurizes the container that holds the product. Typically, it takes about ten minutes for the ash tree to absorb the product into the trunk of the tree. 

EAB Treatment


  1. Susceptibility
  1. Reporting EAB
  1. EAB Management 
  1. EAB Mapping
  1. EAB Activity Periods
  1. EAB Management for Private Property Owners