It’s Not Too Late to Protect Your Trees from Emerald Ash Borers

If your ash tree’s canopy is thinning, bark is flaking off in patches, or woodpeckers are suddenly interested in your trunk, you may be seeing the signs of an emerald ash borer infestation. These bright green beetles may look harmless—no bigger than a penny—but their larvae are devastating tree killers, and they’ve been sweeping through the Midwest for years.

In late spring, adult emerald ash borers lay eggs in the cracks of your ash tree’s bark. When the eggs hatch, the tiny larvae chew their way under the surface and begin tunneling through the soft layer just beneath the bark. That’s where your ash moves water and nutrients. As the larvae feed, they leave behind winding S-shaped galleries that slowly choke the tree from the inside out.

Over time, your tree’s upper branches begin to die off, bark splits open, and shoots sprout directly from the trunk—a desperate attempt by the tree to survive. Left untreated, the damage builds year after year until the entire tree fails. Most infected ashes die within 2–4 years.

The signs are easy to miss at first. You might notice leaf loss at the top or a few random bare branches. But under the bark, the real destruction is already happening. In winter, hungry woodpeckers will peel away bark to get to the fat larvae beneath, leaving behind telltale patches of pale, stripped wood.

Emerald ash borers aren’t just a threat to individual trees—they’ve reshaped entire neighborhoods and forests across Illinois and the Midwest. That’s why timing is key when it comes to treatment. The ideal window is late spring to early summer, before most larvae have begun burrowing deep into the tree. But even if that window has passed, some treatments—such as emamectin benzoate—remain highly effective when applied later in the summer and into fall. These treatments are injected directly into the trunk, delivering protection for up to two years and stopping even advanced infestations in their tracks.

If you need help from a local tree specialist who can explain the process of protecting your trees give Steven C Jones a call at Trees Please in Grafton, IL at 618-581-4096. It’s not too late to save your ash.

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