Emerald Ash Borer


emerald ash borer

Hennepin County, which includes all of Shorewood, is part of the Minnesota Department of Agriculture quarantine area, which restricts wood from being removed from the county. EAB has not been reported in Shorewood. If you have an arborist indicate your trees are infected, please report to the city at 952.960.7900.  

What is Emerald Ash Borer?

EAB is one of America’s most destructive tree pests.  Its larvae kill ash trees by tunneling into the wood and feeding on the tree’s nutrients.  Since its accidental introduction into North America, EAB has killed tens of millions of ash trees in 35 states. Infestation signs include one-eighth inch, D-shaped exit holes in ash tree bark and winding tunnels under the bark. The biggest risk of spreading EAB comes from people unknowingly moving firewood or other ash products harboring larvae. There are three easy steps Minnesotans can take to keep EAB from spreading:

  1. Don't transport firewood. Buy and burn local firewood to prevent the spread of EAB.
  2. Be aware of quarantine restrictions. If you live in a quarantined county, be aware of the restrictions on the movement of products such as ash trees, wood chips, and firewood. Details can be found online.
  3. Watch your ash trees for infestation. If you think your ash tree is infested, go to mda.state.mn.us and use the Does my Tree Have Emerald Ash Borer) checklist or call MDA at 888-545-6684 to report concerns.

If you are concerned about an ash tree on your property, the city now offers free tree inspections of ash, oak and elm trees. Contact city hall, 952.960.7900, to set up an appointment.

Other helfpful links:

U of MN-Insects in MN confused with EAB

Talk to a ISA certified arborist (substitute Shorewood licensed tree care companies) about developing an ash management plan on your property. The city recommends the following strategy:

  • Identify ash trees on your property.
  • Inject healthy, structurally sound large ash trees to protect them over time. (Soil drench is not advised.)
  • Remove ash trees smaller than 10 inches in diameter, along with ash trees demonstrating poor structure or wounds.
    • All ash tree removal should take place in the winter when the insects are inactive.
  • Replace removed trees with diverse ash replacement options.
  • Properly manage firewood. Metro area counties are under a firewood quarantine. Follow these guidelines:
    • Dispose of all ash wood at the city brush drop-off, or chip it into mulch.
    • Keep firewood local. There is a large fine for moving firewood out of a quarantined county. If you plan to travel, purchase certified firewood at your destination

Treatment: Ash trees should be injected with emamectin benzoate every two to three years for at least 10-15 years. After all of the untreated ash trees have died, EAB's food source will be limited, reducing its population. At that point, the interval between treatments will likely increase to three to six years, depending on pest conditions.