Tree Pests: Emerald Ash Borer

EAB management for homeowners

If you have ash trees, learn more about EAB before you act. The potential threat of EAB is real, but acting without understanding the specific threat to your trees, regulations, quarantines and your options could cause the unnecessary loss of treasured shade trees.

Until EAB has been confirmed in your county, or at least 15 miles from your home, then no action is necessary. But, once it has been confirmed, then it is time to consider your options. To assist with your decision making, following these simple steps.

Assess value of individual ash trees

The first step in determining whether or not to invest time and money in saving an ash tree is to evaluate its relative value based on its position in the landscape, its condition, the cost of removing and replacing it vs. keeping it alive, and your willingness to invest resources in it consistently. Once you have determined the value of your ash tree, you are ready to take action.

Low-value ash trees

Trees in poor condition for any reason, ash trees not integral to the landscape, and trees the owner doesn’t wish to invest resources in to protect chemically.

Possible actions:

  • Intersperse replacement trees among ash trees, so they can become established and grow before ash trees die.
  • Cull out ash in poor condition.
  • Allow non-hazardous trees to die and fall. Remove potentially hazardous ash before they fall.
  • Replace dead ash with non-susceptible, site-appropriate replacement species.

Moderate-value ash trees

Trees the owner wishes to keep alive until replacement trees are large enough to provide benefit.

Possible actions:

  • Intersperse replacement trees among ash trees, so they can become established and grow before ash trees die.
  • Begin appropriate pesticide treatment. Continue pesticide treatments on yearly basis until non-susceptible, site-appropriate replacement trees are of adequate size.
  • Remove ash as needed after discontinuing pesticide treatment.

High-value ash trees

Trees that are important to the landscape and the owner is willing to invest resources on a yearly basis. Trees must be in good condition initially.

Possible actions:

  • Maintain or improve vigor of high value ash.
  • Begin appropriate pesticide treatment and repeat on vigorous trees yearly.
  • Assess condition and value of chemically protected ash trees yearly.

Replacing ash trees

Replacing with the right tree, in the right place, will help your landscape recover from EAB. For ash tree replacement suggestions, check out the following MU Extension publications.