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Spring is the Time to Prevent Tree Damage from Invasive Insects

Emerald Ash Borer has Killed Thousands of Maryland’s Ash Trees

With spring in full bloom, the Maryland Department of Natural Resources reminds residents that now is time to save trees from a destructive pest. The Emerald Ash Borer (EAB) is an invasive insect that has been spreading across the state since 2003, and has already killed thousands of ash trees across Maryland.

This small, green insect has spread to every county west of the Chesapeake Bay, and to Queen Anne’s, Talbot, and Dorchester counties on the Eastern Shore.

In addition to ecological and economic damage, EAB infestation can cause ash trees to snap, creating safety hazards where ash are growing near homes or streets.

“Now is the time to act to save your ash trees,” said Colleen Kenny, forest health watershed planner for the Maryland Forest Service. “The first indicators that you might have EAB are increased woodpecker damage and thinning foliage. However, you should not wait until you see signs of damage to begin treatment.”

Anyone who has ash trees or think they might have an infestation should first get an assessment from a Maryland Licensed Tree Expert.

For most of Maryland, the most effective treatments are trunk injections of emamectin benzoate, which must be conducted by a licensed pesticide applicator. Treatments are most effective when applied early to healthy trees. Once a tree has lost about one-third of its foliage, it is usually too late to treat.

For many Eastern Shore residents, treatment is not practical. Anyone who does not or cannot apply treatments should remove infested trees promptly. Also, firewood should be burned only near where it is bought instead of moved from one area to another.