How to Spot an Ash Tree with Emerald Ash Borer in PA

Key Takeaway

• Emerald ash borer infestations often go unnoticed for years because the beetle feeds beneath the bark before visible symptoms appear on the outside of the tree.

• Homeowners in Westmoreland and Allegheny Counties can identify a likely infestation by looking for S-shaped galleries, D-shaped exit holes, and unusual woodpecker activity on their ash trees.

• Dead ash trees are structurally dangerous and should never be treated as a DIY removal project because the upper trunk becomes brittle as the tree dies from the top down.

• Acting early gives you more options, including potential treatment, whereas a fully dead ash tree will almost certainly require professional removal.

If you have an ash tree in your yard and it is losing its canopy from the top down, you are probably not imagining things. That thinning crown, that peeling bark, those strange D-shaped holes the size of a pencil tip are the calling card of one of the most destructive tree pests Pennsylvania has ever seen: the emerald ash borer. This beetle has been quietly working through southwestern PA for years, and many homeowners in Westmoreland County do not realize what is happening until the tree is already past saving.

The problem compounds quickly. A tree that looks merely stressed in spring can be structurally compromised by fall, and a dead ash becomes genuinely hazardous because of how it dies. If you are in the Manor, PA area and you suspect one of your trees is affected, understanding what to look for can protect your property and your family. Getting a professional assessment early is far safer and more cost-effective than waiting until a brittle trunk threatens your home or a neighbor's fence.

What Manor, PA Homeowners Should Know About Emerald Ash Borer

Knowing how to recognize an ash tree is the first step in identifying whether emerald ash borer is the problem. Ash trees are common throughout Westmoreland and Allegheny Counties, planted in yards, along streets, and at the edges of wooded lots. They have compound leaves with five to eleven leaflets arranged in opposite pairs, a diamond-patterned gray bark on mature specimens, and a distinctive paddle-shaped seed called a samara that hangs in clusters.

The emerald ash borer, a metallic green beetle originally from Asia, was first confirmed in Pennsylvania in 2007 and has since spread into nearly every county in the state. Once it arrives, it is relentless. The larvae feed beneath the bark in winding S-shaped channels that cut off the tree's ability to move water and nutrients, effectively starving it from the inside. By the time most people notice something is wrong, the infestation has been active for at least two to three years. In Westmoreland County specifically, Brinko Tree Service has seen this pattern repeat across properties in Manor, Irwin, and Harrison City, where ash trees that appeared mildly stressed in one season were structurally unsound by the next.

Signs Your Ash Tree Has Emerald Ash Borer

Catching this pest early gives you the best chance of saving the tree or removing it safely before it becomes a hazard. Here is what to look for:

• D-shaped exit holes, roughly one-eighth of an inch wide, on the trunk or major branches where adult beetles have emerged.

• S-shaped or serpentine galleries visible under peeling bark, created by larvae feeding through the cambium layer.

• Crown dieback starting at the top of the tree and progressing downward, often beginning with individual branch tips turning brown.

• Epicormic sprouting, which appears as clusters of small shoots growing directly from the trunk or base as the tree makes a last effort to survive.

• Heavy woodpecker activity, especially flickers, tearing at the bark to reach larvae underneath, leaving large rough patches on the trunk.

No single sign is proof on its own, but two or more of these symptoms together are strong evidence that your tree is infested. If you are unsure what you are looking at, a certified arborist can confirm the identification during an on-site visit.

How Ash Trees Die and Why It Makes Removal Dangerous

Understanding how the emerald ash borer kills its host helps explain why infected trees require professional attention. The beetle larvae disrupt nutrient and water flow from the canopy down, so ash trees die from the top down rather than from the root system up.

The Upper Trunk Turns Brittle First

This top-down death pattern creates a serious structural problem. By the time the lower trunk looks visibly dead, the upper sections of the tree have often been dry and brittle for months or even a full season. Wood in that condition does not behave predictably. It can snap under its own weight, split unexpectedly during cutting, or fall in a direction that is nearly impossible to control without rigging equipment and an experienced crew.

This is not a weekend project. A homeowner with a chainsaw has no reliable way to assess how far the wood degradation extends or how to safely direct a falling section. Professional crews use rigging systems, bucket trucks, and section-by-section removal techniques specifically because of how unpredictable a dead ash can be. For more on what professional hazardous tree work actually involves, Safe Tree Removal: Why You Should Hire Professional Arborists is a useful overview.

When Treatment Is Still an Option

If the infestation is caught early, typically when crown dieback is below thirty percent of the canopy, systemic insecticide treatments applied by a licensed applicator can be effective. These treatments protect healthy tissue and slow or stop larval damage. However, once a tree is more than half dead, treatment is not cost-effective, and Tree Removal becomes the practical path forward. After removal, Tree Trimming of nearby trees can help assess whether any connected canopy has been stressed by the same pest pressure.

Other Pest Threats in the Region Worth Knowing

Homeowners across Irwin, Harrison City, and Greensburg dealing with ash borers should also be aware that the spotted lanternfly is under quarantine across most of Pennsylvania, including the southwest. This invasive pest stresses maples, black walnut, birch, and willow trees over time, weakening them in ways that are sometimes mistaken for disease. If you have multiple struggling trees of different species, the issue may not be ash borer at all. A professional tree assessment can distinguish between pest damage, disease, root stress, and structural decline.

Cost, Timeline, and What to Expect

The cost of addressing an ash borer situation depends on several factors: the size of the tree, how advanced the infestation is, how close the tree is to structures or utility lines, and whether stump removal is needed afterward. There is no single figure that fits every situation, and any company that quotes you a price without seeing the tree in person is guessing. For a broader sense of what drives pricing, How Much Does Tree Removal Cost? A Complete Pricing Guide covers the main variables in detail.

Here is what the process generally involves:

• An on-site assessment to evaluate the tree's condition and the safest removal approach.

• Coordinating with utility companies if lines are nearby before any work begins.

• Section-by-section removal of brittle upper limbs before the lower trunk is felled.

• Stump Grinding to remove the remaining root flare, which also eliminates a beetle breeding site.

If a tree has already fallen or is at immediate risk of falling, that qualifies as an Emergency Tree Service situation and should be treated as one.

People Also Ask

How can you tell if an ash tree is dying from emerald ash borer?

Look for crown dieback starting at the top of the canopy, D-shaped exit holes about one-eighth of an inch wide in the bark, and S-shaped tunnels visible when bark is peeled back. Heavy woodpecker activity is also a reliable indicator. Two or more of these signs together strongly suggest an active infestation.

Can an ash tree survive emerald ash borer?

Yes, if the infestation is caught before significant canopy dieback has occurred. Systemic insecticide treatments can be effective in early-stage infestations. Trees that have lost more than half their canopy are generally too far gone for treatment to be practical, and removal is usually the recommended course of action.

Is it dangerous to remove a dead ash tree yourself?

Removing a dead ash tree without professional equipment is genuinely dangerous. Ash trees die from the top down, which means the upper trunk becomes dry and brittle before the tree looks visibly dead from the outside. That brittle wood can split or fall unpredictably, creating serious injury risk for anyone without rigging equipment and proper training.

How quickly does emerald ash borer kill an ash tree?

A heavily infested ash tree typically dies within two to four years of initial infestation. The timeline varies by tree size, health, and beetle population density. Because larvae feed beneath the bark for one to two years before adult beetles emerge, most trees are significantly damaged before the infestation is even noticed.

FAQ

How do I know if my tree is actually an ash and not another species?

Ash trees have compound leaves with five to eleven leaflets in opposite pairs, a distinctive diamond-patterned gray bark on mature trunks, and paddle-shaped seeds that hang in clusters. If you are unsure, a tree care professional can confirm the species during an on-site visit before any treatment or removal decisions are made.

Should I remove a dead ash tree before or after winter?

Removing a dead or dying ash tree before winter is advisable if it poses any risk to structures, vehicles, or people. Ice and wind loads increase the chance of failure in a compromised tree. That said, professional crews can work year-round, so if the tree is an immediate hazard, seasonal timing should not delay the call.

What happens to the stump after an ash tree is removed?

The stump and surface roots can be removed through stump grinding, which reduces the wood to mulch below grade. This is especially worth doing with ash trees because the remaining wood can still harbor beetle pupae. Grinding eliminates the material and removes a potential habitat for continued pest activity.

How do I choose a reliable tree service for ash borer removal?

Look for a licensed and insured company with documented experience in hazardous tree removal, not just routine trimming. Tree Removal Companies: How to Choose the Right One is a practical starting point that outlines exactly what to ask before hiring anyone.

Brinko Tree Service: Trusted Ash Tree Removal Across Westmoreland and Allegheny Counties

With nearly 20 years of experience serving homeowners in Manor, Irwin, Greensburg, Export, and across both Westmoreland and Allegheny Counties, Brinko Tree Service has handled hundreds of ash tree removals, including trees that were far too dangerous for any homeowner to safely address without professional equipment and crew. Our team includes ISA-certified arborists who understand how the emerald ash borer progresses in this region, how to assess structural risk in brittle wood, and how to remove a failing tree without putting your property at risk.

If you have an ash tree showing any of the warning signs described here, do not wait for a branch to come down on its own. Early action protects your yard, your home, and everyone around it. We serve the full Westmoreland and Allegheny County area and will give you an honest, straightforward assessment of what your tree needs.

Visit Brinko Tree Service or call 412-373-7450 today. Our experienced crew will assess your ash tree, explain your options clearly, and handle the job safely from start to finish. Contact us for more information.