Emerald Ash Borer
Emerald Ash Borer Assessment & Plan
The Emerald Ash Borer (EAB) is an invasive insect from Asia that is killing ash trees in North America. It was first found in the United States in southeast Michigan in 2002. By 2018, EAB had spread to Vermont, and by May of 2021 EAB was confirmed to be in Colchester. The USDA Emerald Ash Borer website reports that, “Today, EAB infestations have been detected in 36 states and the District of Columbia” and that; “EAB is the primary cause of our nation's extensive ash decline. Since its discovery, EAB has killed tens of millions of ash trees and has cost municipalities, property owners, nursery operators, and forest product industries tens of millions of dollars.” Since the arrival of EAB, communities in North America have been unable to successfully eradicate EAB after it has been detected.
Once EAB has infested an ash tree, the probability of the tree dying is greater than 99%. Symptoms of EAB are difficult to assess during the early phases of an infestation, making initial infestations hard to determine. Once EAB symptoms become present, it is estimated that EAB has already been present for 3‐5 years and the ash tree is in danger of declining rapidly and dying over the next 2‐3 years. In these later phases of deterioration, the ash trees become a hazard to property, infrastructure, and to the general public, as the trees become extremely brittle and break easily as their health declines.
The Department of Public Works has completed an inventory, identifying 446 ash trees within the Town’s right‐of‐way and other Town owned property frequented by the public. Absent cost‐effective treatment measures, the most effective and expedient means to remove the public safety risks are to remove all of these trees as quickly as possible. While the removal must be done both quickly and comprehensively, replanting of these trees can be accomplished over a longer period time, and can and should be done more selectively. Of the 446 trees to be removed, 116, or 26% will be replaced as part of this plan.
The proposed EAB Management Strategy is outlined as follows:
- Treatment only for ash trees that have been identified as heritage, historic, memorial, or otherwise significant.
- Proactive removal of all ash trees on Town owned land identified through the ash tree inventory.
- Replanting in areas that have a significant ash tree presence, except where ash trees are along the perimeter of an already heavily wooded area.
- Education and outreach directed toward private property owners.
- A Funding and Financial Plan that optimizes grant opportunities and minimizes inflationary impacts.
The completion of the overall plan is expected to take approximately 8 years, assuming the optimization of grant opportunities. The plan would be funded through a mixture of grant funds, supplemented and leveraged by local funds.
Additional resources regarding EAB:
The following websites have an extensive library of resources related to EAB, including videos, infographics, and brochures:
- Emerald Ash Borer Network:
- Vermont Invasives:
- Vermont Urban & Community Forestry Program’s EAB management webpage:
The Town has provided the following resources and outreach materials:
- Link to full version of the Emerald Ash Borer Assessment and Plan
Private Property Ash Trees
The majority of the forested areas in Colchester are privately owned and are outside of the Town’s direct control. If you have an ash tree on your property, please consider the following management options:
- Treatment: Chemical control treatment can be used to preserve ash trees at risk of an infestation. There are various chemical options to choose, and these options can be effective, however they require reapplication every 1-3 years for the life of the tree. Most pesticides used to treat ash trees for EAB are restricted-use pesticides that require the application to be done by a certified pesticide applicator. Additionally, the effectiveness depends on factors such as tree health, tree age, pest population, site conditions, and frequency of application. An International Society of Arboriculture (ISA) Certified Arborist can be contacted to assess whether your tree is suitable for treatment.
Please visit the website below for additional information regarding treatment options:
- Tree Removal: Ash trees that are dead and dying can become a high risk to you, your property, and general public safety. Ash trees can be removed if treatment is not a viable or preferred option. Here is a link to the Vermont Urban & Community Forestry Program webpage, which recommends different species appropriate for replanting: https://vtcommunityforestry.org/sites/default/files/2022-11/complete-vt-tree-selection-guide-2022.pdf
For more information, the Vermont Urban & Community Forestry Program provides a Homeowner’s Guide to Emerald Ash Borer: https://vtcommunityforestry.org/sites/default/files/2022-10/homeownerseab.pdf
Who to contact if I have any questions regarding private property ash trees:
- An observation of EAB can be reported online at: https://vtinvasives.org/reporting-emerald-ash-borer or call the USDA APHIS hotline at 1-866-322-4512.
- The Vermont Urban & Community Forestry Program is a collaborative effort of both the Vermont Department of Forests, Parks, and Recreation and UVM Extension. Learn more about the staff and partners at
- Ash Tree Protection Services Contact List: