8 Clear Signs of Emerald Ash Borer Damage

What does emerald ash borer damage look like?

This article provides you with all the details on signs and symptoms to look out for. These allow you to take urgent action.

The survival and recovery of your tree from emerald ash borer activity largely depend on how early the problem is spotted and the urgency of treatment.

Emerald Ash Borer Signs

The emerald ash borer is a notorious tree pest known to cause extensive destruction to woodland trees.

During infestations, these bright metallic-green beetles can spread wholly and rapidly destroy trees within 1 to 4 years. While that’s true, lots of people have problems identifying these pests.

Emerald Ash Borer Damage

It’s necessary to state that these beetles mainly target ash trees hence the name.

Unlike what most people assume, adult emerald ash borers mainly feed on leaves but cause little to no damage to these trees.

However, the damage results from their reproduction habits.

Adult female members of this beetle species target ash trees to lay their eggs. Such eggs are laid on the trunk of ash trees. These eggs hatch into lar, which bears through the tree’s bark.

Below the bark is where feeding takes place, forming serpentine galleries.

What follows through this reproductive action is what affects your ash trees. The transportation or movement of nutrients and moisture from the soil to the leaves is affected as these larvae feast on the tree.

This action continues until these larvae fully develop and emerge.

Ash Borer Signs to Look Out for

If you’ve spotted emerald ash borers and suspect an ongoing infestation, there are ways to identify such.

These beetles leave behind tell-tale signs, which, when assessed, confirm their presence. While that’s true, other pests can be mistaken for these. The signals provided below should help with easy identification.

Signs of emerald ash borer presence include serpentine or S-shaped galleries underneath tree bark, more frequent woodpecker activity, and canopy dieback are noticed.

Other signs include the splitting of tree bark, the appearance of D-shaped exit holes, and cream-colored larvae underneath the bark.

What more? A condition known as epicormic sprouting may be noticed.

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An actual sighting of emerald ash borer is also possible. With these signs and symptoms identified, let’s briefly discuss each to better explain how they look.

i. S-Shaped Galleries

When emerald ash borer larvae find their way underneath the bark, they start to feed off the tree.

Such feeding activity leads to the creation of serpentine-shaped galleries, which are only evident when the bark covering the affected area is lifted.

These galleries are found to be packed with sawdust-like material. These are also called frass and consist of digested plant material fed on by these pests.

ii. More Frequent Woodpecker Activity

One common sign of emerald ash borer infestation is the increased activity of woodpecker birds. It’s obvious what these birds are after.

Having sensed the presence of these larvae and pupae, they seek out such areas to prey on the larvae. This is a beneficial activity that helps with pest control.

iii. Canopy Dieback

We mentioned earlier that the continued larval action underneath the bark of ash trees affects the free movement of water and nutrients to the leaves.

With such a reality, it’s only a matter of time before the effects begin to show.

This is first identified by leaf thinning, mainly within the first three years of infestation. After that, branches also die out before the entire tree is affected.

iv. Splitting of Tree Bark

The burrowing action of newly hatched larvae finding their way through the bark and the exit holes created by mature emerald ash borer beetles create bark splits.

These splits are due to the formation of callus tissue around larval gallerieTheTheir vertical appearance often identifies these

v. Appearance of D-Shaped Exit Holes

Another sign of emerald ash borer beetle you might find is a D-shaped exit hole. This usually measures around 1/8 of an inch in diameter.

Unlike those created by newly hatched larvae, these are produced by mature adults exiting the infested tree. Every newly hatched larva leaves the same way after maturing.

vi. Cream-Colored Larvae

When probing for emerald ash borer presence, you will likely come across their cream-colored larvae. As mentioned earlier, these lie beneath the bark.

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If you’ve spotted tiny cream-colored larvae, further confirmation can be made by checking the end of their abdomen, where pincer-like appendages are identified at the end of their stomach.

These vary in size depending on maturity. Fully grown emerald ash borer larvae will measure around 1.5 inches in length.

vii. Epicormic Sprouting

Epicormic sprouting is a stress condition in trees that causes them to sprout new limbs at unusual pointTrees adopt this defensive mechanism to survive the onslaught of pest activity. You may find new stems growing below the affected areas.

Added to the other signs mentioned, this condition points strongly to the presence and action of emerald ash borers. Immediate action will be required to eliminate these pests.

viii. Sighting of Adult Emerald Ash Borer

One other irrefutable symptom of emerald ash borer presence is the actual sighting of the beet. Adults are about 3/8 to 5/8 of an inch long.

They’re distinguishable by their bright metallic-green wings.

To further confirm you’re dealing with these, turn or flip one of these to look at their abdomen. You’ll observe their core to be purple or coppery red.

Action is needed

Having identified all or some of these infestation signs, you’ll need to call for urgent help. Tree specialists like arborists could offer solutions by combating these pests.

However, not all situations can be salvaged. Sometimes, significant damage might have been caused, thus making it difficult to remedy the problem.

Under such circumstances, removing the tree will be the best line of action. Preventive control is the best way to prevent ash trees from being attacked by these pests.

Discuss with your tree specialist effective preventive control options to keep your trees safe. This might require scheduled pest inspections and treatments.

These emerald ash borer signs discussed are vital to identification and control. Unfortunately, most people only notice when the problem is advanced and the symptoms begin to show.

Keeping a maintenance routine will help with prevention.

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