Tens of millions of ash trees in New Jersey are counting their days, as a relentless pest known as the emerald ash borer wreaks havoc nationwide.

Emerald ash borer (NJ Dept. of Agriculture)

The small green beetle has been detected in more than half of the states in the country, and more than half of the counties in New Jersey. While they try their best to slow the process, state officials believe it's just a matter of time before New Jersey's ash population is gone completely.

The actual threat to the trees comes from the insects' larvae, which feed on the trees' living tissue. After initial infestation, the trees have just a few years to live, and since EAB start at the top of a tree's crown, detection typically comes after it's too late.

"It's estimated that in all other states where EAB has been found, it's going to kill over 99 percent of the ash there," said Rosa Yoo, regional forester with the New Jersey Department of Environmental Protection. "We're not going to stop it. It's going to continue moving."

But processes can be implemented that may draw EAB populations away from certain areas. Already-affected trees can be removed to avoid the emergence of beetles that will end up harming additional ash trees down the road.

The state's forests consist of an estimated 24.7 million ash trees. But the species is also common along residential streets and in backyards and parks.

Yoo said the latter population is of most concern.

"If those trees are not protected with either a pesticide or slated for removal, and they die, they can pose a hazard," she said. The weaker the tree, the worse shot it has at withstanding storm-force winds.

Identifying an ash tree (NJ Dept. of Agriculture)

As of July, EAB has been detected in 12 of New Jersey's 21 counties:

  • Bergen
  • Burlington
  • Essex
  • Hudson
  • Hunterdon
  • Mercer
  • Middlesex
  • Monmouth
  • Morris
  • Somerset
  • Sussex
  • Warren

But, Yoo said, it's very difficult to determine where EAB is not located. The first New Jersey detection occurred in Somerset County in 2014.

All ash trees in the state are considered at high risk for EAB, according to the state Department of Agriculture. The department urges homeowners to work with a certified tree expert or approved consulting forester to determine whether trees in question should undergo a treatment program or be removed.

Sign up for the WPG Talk Radio 104.1 Newsletter

Get South Jersey news and information e-mailed to you every week.