Beetles Threaten Ash Trees in NJ

By Lauren Wanko

Entomologist Paul Kurtz inspects an ash tree for signs and symptoms of infestation. This tiny, jewel-toned beetle may look harmless, but the emerald ash borer is wiping out ash trees throughout half the country and parts of Canada. And it’s found its way to New Jersey.

“It’s one of the things that we’re concerned with because it has killed roughly 250 million trees in the U.S. and it’s in 23 of our states,” Kurtz said.

The emerald ash borer, or EAB, first appeared in Michigan about 10 years ago. At the time, the insects were living in wooden crates shipped from Asia. In May, a landscaper spotted infested trees in Somerset County and the beetle was just found in Burlington County. Kurtz says so far the Department of Agriculture’s identified six infested trees.

“Well New Jersey and Delaware have been known as the doughnut hole. All the other states around us have had emerald ash borers and we’ve been anticipating it,” said Kurtz.

The EAB is about a half an inch long and an eighth of an inch wide. It only feeds on ash trees. It can fly up to 10 miles per flight. A female lays her eggs on the bark and the larvae begins eating the live tissue under the bark.

“What it does as it feeds, it creates these serpentine shaped galleries and while it’s doing that, it’s cutting off that tree’s transport system,” said Kurtz. “And it’s basically breaking the lines of the water and nutrients going up to the tree.”

The tree dies of dehydration. A year later, when the larvae becomes an adult, it emerges through the bark and creates D-shaped holes an eighth of an inch wide. Kurtz says this is one of the signs homeowners with ash trees should look for. All the trees infested in New Jersey are on the private property of businesses. The Department of Agriculture tells NJTV News they want to protect the privacy of affected businesses owners.

The New Jersey Department of Agriculture, along with other state and federal agencies, have set up traps in an effort to monitor and detect the insects’ location. Since 2010, about 1,750 traps have been deployed throughout the entire state. The insect found in Burlington County was a caught in one of these traps, making it the first EAB ever found in a trap here in New Jersey.

“This is what we refer to as the purple sticky trap and it has three different attractors for EAB. One is the color,” Kurtz said.

Two lures also hang inside the trap.

“Outside the trap is a sticky viscous material applied outside and insect gets trapped and dies,” said Kurtz.

As for the emerald ash borer found in Burlington County, entomologists are still working to identify the infected tree.