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Insect responsible for removal of trees

Stumps line the stretch of the Green Monster between the Stadium View apartments and President Dan DiBiasio's home. The University was forced to remove all ash trees on campus following an infestation of the insect ash borer. (photo/ Kaitlin Durbin)

 Ohio Northern University recently removed all the ash trees from campus in response to an infestation by a voracious, ash tree- eating beetle. This comes nearly one decade after the insect was discovered.

The perpetrator of this damage is a small, narrow insect known commonly as the emerald ash borer. This invasive species, introduced from Asia, was first discovered in Michigan in 2002. It has been spreading the last decade throughout the Midwest, Ohio Valley and into Canada.

The destructive potential of this insect is immense, effectively killing off an infected ash tree within a few years. Borer larvae chew tunnels through the soft tissue underneath the bark, cutting off the tree’s nutrient supply before becoming an adult and moving to the next tree.

“What makes this insect unique and destructive is that it attacks all types of ash, unlike diseases that might be specific for a species,” Brian Keas, professor of biology, said.

The borer has made a home in Ada for at least the last three years, wiping out the University’s white, black and green ash trees in its wake.

Currently there is no solution to purge the insects other than cutting down the trees necessary for their survival.

“It was with the recommendation by the city of Ada that we remove all the ash trees from campus,” Tony Wolke, the grounds manager for Ohio Northern, said.

The Physical Plant cut down all 60 of the ash trees on campus and will grind up the stumps to finish the process.

Wolke says the University will plant 20 trees of varying species each fall to replace the ash trees.

Similarly, the village of Ada also cut down ash trees susceptible to the borer’s appetite.

This trend is not uncommon across towns in the United States. The borer has been spreading uncontrolled for years and currently there are no other options to protect the ash trees from infestation other than getting rid of them.

Pesticides are not a viable option since they would only guard the trees temporarily, requiring at least annual reapplication. This could be a costly endeavor, especially given the widespread nature of the problem.

 “The outlook doesn’t look good for the ash,” Robert Verb, professor of Biology, said. “The insect (emerald ash borer) might potentially affect billions of ash trees in the years to come.”

The extent of damage seen with the emerald ash borer is compared to the havoc caused by recent fungus infections that targeted and killed chestnut and elm trees. Their disappearance could have a long-term impact on industries that depend on ash wood for their production lines.

Efforts to slow down the insect’s movement have proved unsuccessful in recent years. Such measures included a ban on transport of firewood and cutting down “quarantine zones” of ash trees to prevent the insect’s migration.

However, the borer is currently winning the battle. Ohio recently lifted the ban, in response to widespread infestation, but Ohio Department of Agriculture still recommends caution when transporting firewood across the state.