Beech Leaf Disease Nematode
Beech leaf disease can kill beech trees of all ages. Mature trees can be killed in six to ten years, while young trees can be killed in as little as two to three years. Beech trees are valued by wildlife for nesting sites, as well as for the nuts they produce that are a common forage of birds, black bears, and other wildlife.
Common Name: Beech leaf disease nematode
Scientific Name: Litylenchus crenatae mccannii
Native Range: Unknown
Background
Beech leaf disease was first detected in 2012 in Ohio. The first infected stand in NY was discovered in 2018. In the summer of 2022, the NYS Department of Environmental Conservation (NYSDEC) confirmed the presence of beech leaf disease in over 30 counties in NY, including the first infestation in the APIPP PRISM in Herkimer County.
Little is known about the disease, and researchers are still trying to determine the cause of it and how it spreads. The disease is believed to be associated with a nematode (worm), Litylenchus crenatae mccannii. However, because this nematode has also been found on trees that are not showing symptoms of the disease, it is unclear if the nematode is the sole cause of the disease or is only a vector of unknown pathogens such as a virus, bacteria, or fungus. This disease is seen in the leaves of affected beech trees and symptoms include dark striping between the leaf veins, curling, and/or a leathery texture. The striping is most easily seen on the underside of the leaves and is visible when looking up into the tree canopy or when holding branches up to the light. In early infestations, only a few leaves may be affected, and a single tree can have both heavily infected and unaffected branches.
Habitat
Beech leaf disease has been found on a variety of beech species, including American beech (Fagus grandifolia). American beech is a dominant canopy tree in eastern deciduous forests, including the forests of the Adirondacks. Beech trees thrive in moist, well-drained soil.
NYS Distribution Map
NOTE: If you receive a “sign in” message, click cancel to continue. Confirmed observations of Water chestnut submitted to the NYS Invasive Species Database. For more information, visit iMapInvasives
Identification
Trees affected by beech leaf disease will display dark bands between the leaf veins. This is particularly easy to spot when looking up at a backlit canopy. The leaves will also curl and take on a leathery texture that is quite unlike the typical papery texture of healthy leaves.
Impact
Beech leaf disease can kill beech trees of all ages. Mature trees can be killed in six to ten years, while young trees can be killed in as little as two to three years. Beech trees are valued by wildlife for nesting sites, as well as for the nuts they produce that are a common forage of birds, black bears, and other wildlife.
Prevention and Control
There are currently no known ways to manage beech leaf disease. If you see beech leaf disease, please report it using the free iMapInvasives app so that researchers can learn more about this disease. If you do not have a smart device, you can report location information to NYSDEC at or 1-866-640-0652.
