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Emerald Ash Borer

Austin is anticipating the arrival of the Emerald Ash Borer, a non-native beetle that has killed millions of ash trees across North America. 

The Emerald Ash Borer (EAB) has been found spreading in Texas and may already be in Austin. Now is the time to inventory our ash trees and prepare for the impact of EAB.  

A collection of four photos of Emerald Ash Borer, including them sized in relation to a penny, D-shaped exit holes on an ash tree, and their copper abdomen.

A small but mighty pest

About the Emerald Ash Borer

The Emerald Ash Borer is a non-native beetle smaller than a penny. Adults are a metallic green color with a bright coppery-red upper abdomen that can be seen when their wings are raised. EAB lay their eggs in the crevices of ash trees. When the larvae hatch, they tunnel into the tree to feast on layers beneath the bark. These layers allow nutrients to travel throughout the tree, and the damage left in the larvae's wake can eventually kill the tree. 

What will happen to my ash tree when EAB arrives?

An EAB-infested ash tree can become a hazard as the dead branches can snap and fall. Based on the tree’s condition and the tree-owner’s budget, treatment or removal may both be options. View Emerald Ash Borer: A Decision Tree for Central Texas (PDF, 1.2 MB) to help you choose the best course of action. Untreated Ash trees are expected to all die from EAB.

What can I do now to prepare?

We know EAB is nearly here (if not already in Austin). Taking proactive steps is the best thing we can do to protect the health of our urban forest. Here’s what you can do now:

  1. Learn how to identify ash trees and inventory those on your property.
  2. For any ash trees you find on your property, speak with a certified arborist to develop an action plan. Tree service companies are likely to be overwhelmed with requests to treat and remove ash trees when EAB is reported in the Austin area. Contacting a qualified arborist to develop a plan of action before the insect is detected in our area is ideal. You can work together using the Emerald Ash Borer: A Decision Tree for Central Texas (PDF, 1.2 MB) tool to take appropriate action on individual trees. Please note: if you plan to remove trees, you must follow the City of Austin’s Tree Ordinance.
  3. If you suspect you’ve found an EAB or tree damage caused by an infestation, take clear photographs and report the sighting to the USDA using the online form or by calling 866-322-4512. Not sure what to look for? Learn how to identify an EAB infestation.
  4. Avoid bringing ash tree wood to Austin from other parts of Texas, and do not move ash tree wood to other parts of the community. These efforts can help minimize the movement of adult EAB.

How to identify an ash tree

Austin has over one million ash trees, which account for 3% of our total tree population. It’s important to take time to identify any ash trees at your home or neighborhood so that you can make informed decisions about their care or removal.

  • A close up on ash tree bark showing a diamond-shaped pattern.

    Bark: The bark of all ash trees forms a diamond-like pattern. Sometimes the diamond shapes between chunks of bark are more noticeable than others, but with practice, the familiar pattern is easy to detect.

  • An ash tree leaf.

    Leaves: Ash trees have compound leaves in an opposite arrangement. That means that there will be several smaller leaflets around a center stem with pairs of opposite leaflets beginning from the same point. Ash leaflets sometimes have slightly jagged edges.

  • A collection of light green seed pods hanging off an ash tree branch.

    Seeds: All ash trees produce seeds in long, narrow seed pods called samaras, which are shaped like paddles. Thick clusters begin to appear in late spring and often remain on the trees through summer.

Signs of an Emerald Ash Borer Infestation

The following are examples of signs and symptoms of EAB infestation. Remember, EAB only attacks ash trees. These symptoms on other species are not indicators of Emerald Ash Borer.

  • A finger points to D-shaped exit holes on an infected ash tree.

    D-shaped holes: The adult EAB leaves distinct, D-shaped exit holes in the bark and can fly at least a half mile from the ash tree where it emerged. Courtesy of Daniel Herms, The Ohio State University, Bugwood.org.

  • A woodpecker perched on a tree.

    Increased woodpecker activity: Woodpeckers, looking to feast on larvae, will often be more active on a tree infested with Emerald Ash Borer.

  • The trunk of an oak tree with lots of small branches and leaves growing out of the base.

    Dead branches at the top of an ash tree or new growth near the ground: An ash tree may drop leaves from its branches as damage beneath the bark makes it unable to carry nutrients up. Growth near the base of the trunk is a survival strategy often indicating stress in the tree. Courtesy of the Pennsylvania Department of Conservation and Natural Resources – Forestry, Bugwood.org.