Emerald Ash Borer (EAB) in Colorado

What is that little green insect?

If you are in Colorado and your Ash tree has insect damage, there is a good chance it is due to in invasive insect called Emerald Ash Borer. We are happy to come look at the insect damage to your Ash tree (or any other tree). In most cases we can control the insect damage to your tree if we can stop this tiny green bug before the insect kills the tree.

We can help protect your Ash tree with our Emerald Ash Borer treatment. Call us today.

Emerald Ash Borer on leaf
Image courtsey of Brian Sullivan, USDA APHIS PPQ, Bugwood.org


Emerald Ash Borer (EAB) is a non-native species with no natural predators in Colorado to control it from spreading. Emerald Ash Borers kill trees by depriving the tree of vital nutrients. Adult EAB lay their eggs on the bark of the tree. The larval stage feeds under the bark of the tree. Their feeding pattern cuts off the flow of water and nutrients to the tree, eventually killing the tree. As you can see in the picture here (with outter bark removed) the nutrient pathway is disrupted and cannot flow to all parts of the tree. Think of this as a highway, with a giant section of pavement ripped out in the middle, traffic (flow) cannot pass the point with the missing section.

tree nutrient disruption caused by EAB

Emerald Ash Borer Ash Tree Damage


Native to Asia, EAB likely arrived in the United States hidden in wood packing materials. The first U.S. identification of Emerald Ash Borer (EAB) was in southeastern Michigan in 2002. According to the Colorado Department of Agriculture, the first EAB sighting in Boulder was in 2013. There are a variety of treatment options that can serve as a control measure for the EAB, but they are not a cure. Our goal at Roots & Shoots Tree Care is to protect the trees that are vulnerable to this pest. If you have a tree affected by the larvae of the emerald ash borer, we can inject your tree with pesticides, which are designed to protect your tree for two years.

Emerald Ash Borer insect

Emerald Ash Borer Treatment


The best way to protect your Ash tree from Emerald Ash Borer damage is through preventative treatment. Treating a healthy Ash tree will prevent damage to the vascular tissue, promoting a healthy canopy.

In most cases, if your tree currently has Emerald Ash Borer damage, it is not too late to save your tree. Generally a tree in a healthy environment can recover from EAB attack if treatment is performed early. Sections of the canopy that have died back cannot leaf out again, but further damage can be prevented, and through pruning a resilient structure can be achieved. Our crew can trim back dead branches to help re-shape and strengthen your tree.

The treatment process includes injection of a systemic insecticide into the tree which then spreads throughout its vascular system. The product is contained within the tree, so it is safe for use in areas where children and pets are active. We utilize the most effective application method, and the most effective product on the market at an affordable rate. The product is effective for 2 years, at which point we will contact you for follow-up treatment.

e are a family owned and operated company, we only apply treatments to your trees that we use on our own trees. We value your trees, and are committed to their long-term success. Contact us today to come out to assess your trees, and put together an integrated health management plan that we monitor, so you can rest assured that your trees' health is in the best hands possible.

Call us today if you have an Ash Tree


Not sure if your tree has Ash Borer damage? Call us today if you are in Boulder, CO or surrounding areas, we can look at your tree and quickly tell you if you have visible damage. Even if you do not have damage, you should treat your Ash tree. Prevention is the best way to save your tree and keep it healthy. If your neighbors have EAB and your tree is not treated, it is only a matter of time until your tree is infected as well.

Adult Emerald Ash Borers are small, bright metallic green (emerald) in color. Adult beetles are typically 10mm to 13mm in length. If you don't see the the tiny green beetle in your tree, you can also identify the invasive pest by the damage to your tree.

How to identify Ash Borer damage:

  • Emerald Ash Borer exit holes

    Exit holes: Tiny "D" shaped exit holes in the bark are the most obvious sign of EAB damage. Note that other beetles can leave similar small holes in tree trunk. The adult stage beetle usually exits the bark in June or July. EAB chew an exit path through the bark in the shape of the letter "D".

  • Emerald Ash Borer crown dieback

    Crown dieback: Dieback of the upper and outer crown begins after multiple years of EAB larval feeding. Trees start to show dead branches throughout the canopy, beginning at the top. Larval feeding disrupts nutrient and water flow to the upper canopy, resulting in leaf loss. Leaves at the top of the tree may be thin and discolored. An example of this is shown below.

  • Leaf eaten by insect

    Leaf Notch: Leaves that have been chewed (or notched) away is a sign that the adult beetle has been feeding on your tree leaves. The edges of the leaves will be notched as the beetle consumes the outer edge of the leaves.

  • Emerald Ash Borer tiny exit holes

    Epicormic Sprouting: When trees are stressed or sick, they will try to grow new branches and leaves wherever they still can. Trees may have new growth at the base of the tree and on the trunk, often just below where the larvae are feeding. An example of this is shown in the picture above, where small branches are growing on the trunk, about 6 feet off the ground.

  • Woodpecker feeding on insects in tree bark Woodpecker feeding: Woodpeckers eat emerald ash borer larvae that are under the bark. This usually happens higher in the tree where the emerald ash borer prefers to attack first. If there are large numbers of larvae under the bark the woodpecker damage can make it look like strips of bark have been pulled off of the tree. This is called "flecking." Presence of woodpeckers does not specifically mean that your tree has EAB, it just confirms that the woodpecker is feeding on some insect in the tree. We can examine the tree and help determine what the woodpecker is feeding on.

Note that some of these signs are not exclusively signs of Emerald Ash Borer destruction. However if you see these signs, it is a good idea to call us so we can look at your tree and apply the appropriate treatment.

How to identify your Ash tree


As their name suggests, the Emerald Ash Borer beetle finds it's home in ash trees. Not completely sure if you have an ash tree? Here are some tips to help identify Ash trees.

Characteristic Description Example
Branch and Bud placement Ash trees have buds (and branches) placed directly across from other (opposite), not staggered. Ash tree identification branch placement
Leaves Ash trees have compound leaves. A compound leaf is made up from several leaflets with a single bud at the base. Ash trees have 5 to 11 leaflets for each bud. Ash tree compound leaves
Bark Young ash trees have a smooth bark appearance. More mature ash trees have a raised, diamond shaped pattern to their bark. Ash tree bark
It is important to note that your tree should have all of the above characteristics if it is an Ash Tree. Some trees have some of these characterists but not all. For example Boxelder trees also have opposite compound leaves however they appear in groups of 3 to 5 leaflets (Ash Trees have 5 to 11).