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The Department of Environmental Management (DEM) is asking Rhode Islanders to monitor their beech trees for signs of leaf damage from Beach Leaf Disease (BLD). Early symptoms of BLD include dark striping on the tree's leaves parallel to the leaf veins and are best seen by looking upward into the backlit canopy. Drastic leaf loss occurs for heavily symptomatic leaves during the growing season and may appear as early as June, while asymptomatic and mildly symptomatic leaves show no or minimal leaf loss. BLD was detected in the Ashaway area of Hopkinton, Rhode Island, in 2020 and in coastal Massachusetts. Before these findings, the disease was only known to be in Ohio, Pennsylvania, New York, and Connecticut.

Because of the seemingly random nature of disease in Rhode Island, DEM encourages homeowners and forest landowners to monitor their beech trees and report any suspected cases of BLD on DEM's Invasive Species Sighting Report webpage. Although BLD is relatively new in the U.S. and information is limited, links to additional information about the disease and photos are posted on the Division of Forest Environment's Current Threats page. If people have further questions, they should contact a licensed arborist or email Nancy Stairs, forestry program supervisor in DEM's Division of Forest Environment, via Nancy.Stairs@dem.ri.gov.

Beach leaf disease was first observed in Ohio in 2012. It's means of introduction is unknown, although it may have arrived in North America through the transport of wood with an invertebrate vector. It causes a disease of beech trees that disfigures leaves and can lead to tree mortality. 

A chance discovery in an Ohio woodland has turned into a multi-disciplinary, multi-agency, and multi-national effort to piece together a puzzle and understand a scourge that is killing trees by the thousands in northern states east of the Great Plains. The leaves of young beech trees are failing somehow. Scientists have figured out what causes the malady; it’s the 'how' that has them scratching their heads. Beech trees are one of the most common trees in America's northern and northeastern forests. Their nut crop feeds birds and other animals, and its wood is prized for bentwood furniture. The symptoms of beech leaf disease were plain to see – sunken dark spots on the leaves, which eventually died – but opinions differed on the cause. Was it bacterial, fungal, or viral? Then, a plant pathologist working for the State of Ohio noticed wiggly things in the leaf lesions. They turned out to be nematodes, microscopic worms that live in the soil, that had somehow managed to make it to the tree canopy 40-50 feet above ground. Nematode samples were sent to Beltsville, MD, for analysis and identification at the Agricultural Research Service (ARS) Mycology and Nematology Genetic Diversity and Biology Laboratory in Beltsville, MD. The nematode, Litylenchus crenatae, turned out to be native to Japan – the first population of L. crenatae found in the Western Hemisphere. The curious thing is that it's not a tree-killer in Japan.