Beech leaf disease (BLD) is a tree disease that causes leaf deformities and leads to mortality in native and ornamental beech tree species. BLD is believed to be caused by the nematode Litylenchus crenatae mccannii (pictured). It is unknown whether the nematode causes all of the damage, or if it is associated with another pathogen such as a bacteria, fungus, or virus. Research on possible treatments is ongoing.
American beech trees are an important component of the northern hardwood forest type (maple-beech-birch) which makes up more than half of the forested land in New York. Many wildlife species rely on beech mast as a main source of energy. The loss of beech trees would cause changes in forest structure that would affect the whole ecosystem.
BLD symptoms appear in the leaves and include striping, curling, or a leathery texture. These signs may be visible year-round, as some beech trees may hold their leaves in winter. Stripes are most noticeable on the underside of leaves and you may see them by looking up into the canopy or holding branches up to the light. Eventually, affected leaves wither, dry, and yellow (NYSDEC).
Since so much about beech leaf disease is unknown, learning of new infestations aids research and management efforts. Reports in counties where BLD has been newly found and in counties where it has not been found are especially needed.
If you think you have found beech leaf disease follow these steps:
Beech trees may show signs of beech bark scale and beech bark disease.
Management: There is still much unknown about how beech leaf disease infects and spreads. Below are a few methods that could be effective for managing or preventing BLD.
Prevention is the best management option. If BLD is present in an area, avoid moving soil, and beech tree material including firewood, branches, twigs, leaves, and seedlings from the infected location. In addition, follow all NYS firewood regulations and don’t move firewood more than 50 miles from its original source.
Disinfect footwear with a solution of bleach and water immediately after walking through stands of trees with BLD.
Chemical: Preliminary findings through the Maine Forest Service show that soil applications of Phosphite products have been effective for managing beech leaf disease. Nematicides may also be an effective chemical control method although application timing is still being researched (University of Massachusetts Amherst).
There is a state-wide effort to track the spread of beech leaf disease. You can help by learning to recognize symptoms of the disease and report observations to iMapInvasives.org, New York’s invasive species observation database.
You can choose any public location to search for signs of beech leaf disease. The map below shows suggested survey sites and confirmed observation sites for beech leaf disease. Data from iMapinvasives.org was used to generate confirmed observation locations. Suggested survey sites were selected based on proximity to confirmation sites and public accessibility.
Searching for invasive species populations in an effort to detect their presence before their populations become too large to manage is vital to reducing the impacts of invasive species on our natural ecosystems.
Click the link below to learn more about the species we’re enhancing early detection efforts for and to join our invasive species Volunteer Surveillance Network to aid this effort (training will be provided).
NYiMapInvasives is an online, collaborative, GIS-based database and mapping tool that serves as the official invasive species database for New York State.
Click the links below to become familiar with iMap