Emerald Ash Borer (EAB)

About the Emerald Ash Borer

Don't let its size fool you: The Emerald Ash Borer represents an enormous threat.

The City has been fighting the Emerald Ash Borer since its discovery in November 2014. The invasive pest was discovered near Columbus Playlot, 10030 Columbus Avenue South. The iridescent green beetle’s larvae feed on the conductive tissues of ash tree bark, which eventually kills the tree.

In an effort to help slow the spread of the insect during 2015, 125 ash trees were removed from City parks within 1 mile of Columbus. To establish a healthy future canopy tree replacement is part of the project and a diverse mix of trees was planted. Some of this work was funded by an $80,000 grant from the Department of Natural Resources.

Ash removals will be conducted during the fall and winter when the insect is dormant and infested trees are easier to identify. The City will conduct another tree survey in January to determine whether there are more infested trees.

MN Department of Agriculture informational handouts

Quarantine in effect

The Minnesota Department of Agriculture (MDA) has implemented a quarantine in multiple counties that prohibit the movement of the following items out of quarantined counties:

Information regarding disposal of quarantined ash tree waste can be found on the MN Department of Agriculture website.

Seasonal information

The Minnesota Department of Agriculture indicates that the active period for the Emerald Ash Borer is May 1st through August 31st. Any pruning or removal of ash trees, branches or stumps should be avoided during this period as doing this may contribute to the spread of the Emerald Ash Borer disease. If ash tree work must be done for safety and hazardous condition reasons the material removed to include the outer 1 inch of the bark/ wood should be chipped on site or it should be transported in an enclosed vehicle to the nearest facility that can process the material. (only the outer 1 inch of bark/ wood harbors the EAB) A list of those approved disposal sites within the quarantine area are listed on the Minnesota Department of Agriculture web page. Pruning and removal of ash trees/ wood may be conducted from September 1st through April 30th.

Do I have Emerald Ash Borer? What does it look like?

The above picture offers a general idea of the Emerald Ash Borer's size and appearance.

Insecticide treatment information

Once EAB arrives in an area, it will remain a constant threat to ash trees for many years to come. If you choose to use an insecticide, it is likely that protective treatments will be needed for the rest of the tree's life. Optimal timing for most treatment methods is mid-April until the end of June.

City and State response

  • MDA staff will conduct a thorough survey of trees in the surrounding area to assess the extent of infestation. Information from this survey will help determine the response strategy implemented by state and local officials. The MDA and MN DNR are working closely with the USDA Animal and Plant and Health Inspection Service in the MDA response.
  • City staff tree inspectors licensed by MDA are prepared to include in our annual city tree inspections the search for EAB in both public and private areas in the City.
  • The City's goal is to communicate the most current information available from the MDA, to encourage residents not to plant ash trees, to recommend residents take extra care of ash trees they are trying to retain, and assure residents our city tree inspection staff will be including the inspection for, and possible detection of, EAB as we do our annual inspections of trees in the city.
  • We do not anticipate a major change in how the City deals with ash trees and EAB until such time as the MDA has completed its survey and makes a recommendation on how best to approach this new tree disease.

Help monitor for EAB in your neighborhood - Wasp Watchers Program information

Love trees?  Want to help save them from invasive pests?  You can be a volunteer citizen scientist and help survey your community for the presence of EAB. With the help of a harmless ground-nesting wasp (cerceris fumipennis) that hunts wood-boring beetles like EAB, we can monitor for the presence of these destructive invasive beetles. The female Cerceris wasps hunt for beetles in the trees and bring their prey back to their nest holes in the ground to feed to their offspring. An observer can easily watch a wasp colony and collect their beetle prey to check for EAB presence. Volunteering is easy and fun and really makes a difference for our wonderful Minnesota trees and forests. For more information, visit the Wasp Watchers website at: https://waspwatchers.umn.edu/

To learn more visit: http://z.umn.edu/waspwatchers or www.cerceris.info

Contact the Wasp Watchers Program Coordinator, Jennifer Schultz at 612-301-8310 or schultzj@umn.edu