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Beech Leaf Disease

a single beech leaf with striping and brown patches
beech tree leaves with dark striping, a symptom of beech leaf disease
Beech leaves exhibiting the striping
associated with beech leaf disease

Beech leaf disease (BLD) affects and kills both native and ornamental beech tree species. It is associated with a nematode, Litylenchus crenatae mccannii. This disease has only been discovered in recent years and much about it, including the full cause and how it spreads, is still unknown. Because of this, DEC is collecting information on symptomatic beech across New York State in the hopes of learning more about the disease.

Disease Symptoms

Symptoms of BLD include:

  • Leaf striping, curling, and/or leathery texture.
    • These symptoms are most easily noticed by looking up into the forest canopy and may be visible from leaf out in May until leaves fall off in October
    • In early infestations, only a few leaves may be affected. Eventually, affected leaves wither, dry, and yellow.
  • Reduced leaf and bud production.
  • Leaf loss has been recorded only in heavily affected trees, but would be noticeable in summer months.
  • A single tree can contain both heavily infected and unaffected branches.
a canopy of beech leaves with the striping associated with beech leaf disease
The backlighting seen when looking up into the forest canopy can
help you spot the leaf striping associated with beech leaf disease.

Environmental Impacts

green beech leaves with some puckering, wilting, and yellow spots
Leaf symptoms caused by beech leaf disease

Beech leaf disease can kill beech trees of all ages though younger trees appear to die more quickly.

In New York State where our predominant forest type is beech/birch/maple, beech is one of the most common forest species. Beech is particularly valued in the forest for hosting nesting sites and providing nuts for birds, black bears, and other wildlife.

Look-alikes and Other Beech Phenomena

Review the table below for other issues you may see on beech trees. It is possible for a beech tree to exhibit symptoms of both beech leaf disease and any of these other impacts simultaneously.

DEC is interested in reports of leaf striping or curling associated with BLD on any beech tree, but we do not manage the other issues listed in the table.

Name Signs and Symptoms About
Beech bark disease (BBD)

Symptoms: The symptoms of this disease are concentrated on the bark. A white, fuzzy coating on the tree's trunk and branches is a sign of the scale insect.

Bark of a tree affected by beech bark disease. Bark has open wounds and is warped in shape.
Photo by Linda Haugen, USDA FS,

Beech bark disease is the result of the combined effects of a non-native scale insect and a canker fungi. The insect pierces and sucks at the tree, allowing the fungus to enter and cause harm internally. This disease is common across New York State and is not managed by DEC.

Most trees die within 10 years of infestation by the insect and fungi.

Learn more (leaves DEC website).

Erineum patch

Symptoms: Yellowish patches appear on the upper side of the leaf. The patches are light green in spring, then fade to orange and eventually brown.

green beech leaves with dead patches between veins
Photo by Eric R. Day, Virginia Polytechnic and State University,

Erineum patch is caused by eriophyid mites and is not typically viewed as a problem. The patches rarely cover enough of the leaf to affect the overall health of the tree.

Learn more (leaves DEC website).

Powdery mildew

Symptoms: Leaves and stems appear to be covered in a white, powdery substance that resembles powdered sugar.

powdery, white fungi on leaves
Photo by University of Georgia Plant Pathology,

Powdery mildew is caused by native fungi and affects a variety of shrubs and trees. This is a cosmetic disease that does not kill the tree but could cause defoliation if not addressed.

Learn more (leaves DEC website).


Symptoms: Small brown or black spots on leaves that eventually cause dead areas. New leaves may curl.

green beech leaves with some brown patching between veins
Photo by Nancy Gregory, University of Delaware,

Anthracnose affects a variety of tree species and is caused by a group of fungi. In beech, the fungi infect the leaves and stems and can cause dieback or some defoliation. The disease thrives in years where there are cool, wet conditions during bud break.

Learn more (leaves DEC website).

Beech blight aphid

Signs: These native insects have a fluffy, white outer coating. Also known as "boogie woogie aphids", the insects will shake or "dance" when the branch is disturbed in order to ward off potential predators.

fuzzy, white beech blight aphids on a branch
Photo by Steven Katovich,

This insect is native and feeds on beech without causing much harm.

Learn more (leaves DEC website).

Beech leaf rolling aphid

Signs: Leaves may curl and appear yellow/faded between the veins.

These injuries are caused by aphids feeding on the leaves. This insect is native and feeds on beech without causing much harm.

Learn more (leaves DEC website).


Signs: Beech retain their dead leaves through the winter.

brown beech leaves in winter

This is a totally normal, common, and harmless feature of beech.

Learn more (leaves DEC website).

Distribution & Habitat

BLD was first discovered in Ohio in 2012 and has since spread to Pennsylvania, New Jersey, Connecticut, Maine, Massachusetts, Rhode Island, and Ontario, Canada. BLD was first observed in New York in 2018 in Chautauqua County and was found in Suffolk and Nassau counties in 2019. It has since spread throughout western, central, and southern NY.

map of New York State counties showing presence of beech leaf disease
New York State counties with beech leaf disease
as of September 2022

We suspect there are infestations elsewhere in the state that we have not yet found, and tracking locations of this disease will help us learn more about its biology.


DEC's Forest Health team is surveying trees across the state to:

  • identify infested stands
  • monitor the disease severity and progression

DEC has partnered with other affected states to conduct research and share findings on beech leaf disease.

Currently, there is no known way to control or manage this disease.

How You Can Help

After reviewing the identification materials on this website, if you think you have seen signs of BLD:

  • Report BLD
  • Follow the NYS firewood regulation, which limits firewood movement to no more than 50 miles, to help prevent the spread of all pests and diseases that threatened our forests. Additionally, if BLD symptoms are observed in an area, avoid moving firewood from that location.

If you have questions about your trees, email photos and location information to Or you may the Forest Health Diagnostic Lab via phone at 1-866-640-0652.

Please note that because the BLD is well documented on Suffolk and Nassau Counties, it is no longer necessary to report the disease on Long Island.

Additional Resources