Beech leaf disease, which has been killing beech trees in New Jersey, is a new disease that was discovered in Ohio in 2012.

Not much is known about it, said Rosa Yoo, forest health specialist with the New Jersey Forest Service. What is known, however, is that the disease is associated with a nematode, which is a microscopic worm.

But Yoo said it is not clear what the full mechanism of the disease is at this time. More research is being done as there are a lot of unanswered questions.

What trees are affected by beech leaf disease?

She said usually what is happening to trees afflicted with beech leaf disease is that smaller, younger trees, typically less than 10 years old are succumbing to the disease within years of symptoms becoming visible.

Beech leaf disease does affect beech trees of all sizes. Larger trees can contract beech leaf disease but Yoo said they seem to be able to hang on a bit longer, around 6 to 10 years after symptoms appear.

The disease can also affect ornamental beech trees that people may have planted in their yards, including weeping beech and copper beech. They are susceptible to the disease, as well, she added.

As far as Yoo knows, beech leaf disease only affects beech trees and not other tree species.

What does beech leaf disease look like?

If you stand under a tree and look at the underside of a beech leaf toward the sunlight, there will be very distinctive dark bands of the leaf tissue between the veins of the leaf, Yoo said.

Beech leaves have a very distinctive leaf vein pattern, similar to a herringbone, she said.

“So, the leaf tissue that is in between those herringbone veins, some of those sections will be darkened when the leaf is held up to the light. It’s much harder to see looking down on a leaf or looking at a leaf flat on a table. It’s most easily seen and very distinctive when the leaf is held up against the light,” Yoo said.

In that section of the leaf between the veins, either all or part of it will be darkened.
Later in the disease progression, the leaves will start to turn brown around the edges and curl. They begin to deform but you’ll still be able to see those dark segments of the leaf between the veins, Yoo explained.

Beech leaf disease (Photo Credit: NJ DEP)
Beech leaf disease (Photo Credit: NJ DEP)

Why is beech leaf disease so dangerous?

It can kill our state’s beech trees. The primary concern there is that there are native beech tree species like the American beech in New Jersey’s forested ecosystem where wildlife, insects, and other organisms rely on them for food, habitat, and shelter. She said there is the concern of losing these tree species from the landscape to beech leaf disease.

Also, beech trees are planted in people’s yards and parks. If they succumb to beech leaf disease, then it becomes an issue of safety.

“We don’t want dead or dying trees hanging over the places where we hang out or park our cars or picnic,” Yoo said.

Is there a cure for beech leaf disease?

There is no known cure, treatment, or prevention for beech leaf disease.

What is happening now is a progression of more areas being affected by beech leaf disease that were not in years past.

Where the disease is progressing and the trees are starting to decline, there are not as many leaves coming out in the spring, and others are dropping early before fall arrives.

Where has beech leaf disease been detected in the Garden State?

Beech leaf disease has been detected and reported in several New Jersey counties, mostly in the northern part of the state, Yoo said.

Beech leaf disease was first detected in Bergen and Essex counties in summer 2020 and is now confirmed in 10 additional counties, according to the New Jersey Department of Environmental Protection.

Those other counties include Burlington, Hunterdon, Mercer, Monmouth, Morris, Passaic, Somerset, Sussex, Union and Warren.

Right now, foresters are looking for any detection of the disease in the southern part of the state. If anyone in the south detects the disease, Yoo said they can take a picture of it, and contact her at the New Jersey Forest Service.

They need to be aware that beech leaf disease has been detected in the state. If there are beech trees in their yard, they should be prepared that the trees may start to decline. This is a good time to call a tree professional to come out and assess the trees. Don’t wait until the trees are dead.

Hopefully, a tree professional can come up with something to help your trees hang on until a treatment or a cure is discovered.

“We are hoping that in the near future researchers come up with a treatment that is effective and consistent at protecting the trees from beech leaf disease,” she added.

Residents who have questions or suspect beech leaf disease in other counties can contact the New Jersey Forest Service's Health Program by calling (609) 292-2532 or emailing


Jen Ursillo is a reporter and anchor for New Jersey 101.5. You can reach her at

Click here to contact an editor about feedback or a correction for this story.

Tis the season for Jersey Long Hot Peppers


More From Beach Radio