MA arborists say beech leaf disease can decimate tree population


Experts say beech leaf disease has the potential to change “the ecology” of Massachusetts as the threat returns this season.

The disease is known to rapidly deplete the beech population.

“It’s growing and it’s still quite widespread,” said arborist Josh Fritz of Hartney Greymont (a Davey company) in Needham and a member of the Massachusetts Arborists Association. “Beech trees provide food for wildlife, and when they disappear, our ecology changes. People are very nervous about that.”

Fritz said the disease affects both American and European beeches, which he says are among the most well-known tree species in the state.

Arborist Natascha Batchelor, also of Hartney Greymont, told Wicked Local last year that beech leaf disease is relatively new in Massachusetts, having first been spotted in Plymouth County in 2020.

“It first appeared in Ohio in 2012 and made its way to Massachusetts by 2020. It was moving fast,” Batchelor said at the time.

Last year:What does the presence of beech leaf disease mean for ecology and the environment?

Since then, beech leaf disease has been found in Bristol, Worcester, Norfolk, Middlesex and Essex counties. Beech trees are among the more common trees in the New England forest, Fritz noted.

In addition to changing the ecology of the area, beech trees provide plenty of shade, Batchelor said last year. If beeches are lost in a certain area, “that area is no longer shaded at that point it becomes a sunny spot… it’s always a problem when we start losing an entire species of tree.”

Fritz explained that the disease is rooted in microscopic worms called nematodes, which eat the trees and cause them to die quickly.

“And in recent years we’re finding more and more locations where it’s present every year,” he said, saying the disease has taken hold in pretty much every area of ​​the state.

On a recent trip to Manchester-by-the-Sea, Fritz noticed that many trees were suffering from beech leaf disease. He said he’s also noticed it in Concord and many other communities in Massachusetts.

“Some scientists believe the disease could be transmitted by birds,” Fritz said, noting that he learned this during a recent conference. Last year scientists hadn’t discovered the airborne element, but now it’s a leading theory, Fritz said.

Is there a remedy for beech leaf disease?

He said scientists are working on a cure for beech leaf disease, but stressed that all people with beech trees can do is “buy time” by having an arborist assess the trees and do maintenance like fertilizing and “vertical mulching” what helps rejuvenate the “root mass” of the tree.

“At the moment we only have defense mechanisms against beech leaf disease,” said Fritz. “Hopefully we can find a cure for this soon. There is no point in trying to attack the nematodes that might be difficult because they are mobile. We need to isolate the pathogen that causes the disease. That would help a lot. It’s a new disease that we’re all still learning about.”

According to Fritz, the sad thing is that centuries-old beeches are affected.

“Those trees that are 200 or 300 years old … you can’t replace them,” he said. “The best thing people can do is have their trees appraised by a local arborist every year every six months if possible. It helps to keep an informed eye on your property.”

Beech trees in Massachusetts fall victim to beech leaf disease, which was first discovered in Ohio in 2012.

Fritz said research into beech leaf disease is still ongoing in Ohio, Maryland and other parts of the country.

“Cleveland Metroparks has been researching this since 2016,” Batchelor said in her interview with Wicked Local last year, adding that the Davey Institute was also involved in the research.

She said the collaboration between the two companies found that beech seedlings and small trees treated with phosphonate soil drenches responded positively over time, showing fuller and healthier crowns than untreated trees. Another study was initiated in 2021 to see if the phosphonate soil treatments could also benefit large trees.

How to recognize beech leaf disease

When it comes to detecting beech leaf disease, Batchelor said the first symptoms are well-defined stripes or bands between the leaf veins. Streaks are visible in spring at early leaf emergence and remain visible throughout the growing season.

She added that sapling-sized trees could die in two to five years once infected.

Where is beech leaf disease located?

According to a study by the University of Rhode Island, beech leaf disease is now found in 12 states and in Ontario, Canada. “It infects beech trees in every state in New England except Vermont,” the study reports.

The National Parks Service states on its website that beech trees “are an important part of a forest ecosystem”.

“Beechnuts produced by the trees have been a culturally important food source for indigenous peoples traditionally associated with this area,” explains the National Parks Service. “They are also part of the diet of many animals living in the forest, including black bears, deer, squirrels and many species of birds.

“A beech forest can also provide shade for plants and other creatures in its undergrowth. Loss of trees can lead to changes in tree canopy structure and species composition. Finally, the loss of beech trees can result in a reduction or loss of important ecosystem services such as water filtration, biodiversity conservation, carbon sequestration, as well as aesthetic, historical and recreational value.”