Beech leaf disease a recently discovered disease affecting Beech trees is widespread throughout Westchester and Suffolk counties. Beech leaf disease can kill beech trees of all ages in 2 to 7 years, though younger trees appear to die more quickly.

Symptoms of this disease are seen in the leaves and include striping, curling, and/or leathery texture. These symptoms may be visible from leaf out in May until leaves fall off in October and are most easily noticed by looking up into the forest canopy. In early infestations, only a few leaves may be affected. Eventually, affected leaves wither, dry, and yellow.

Reduced leaf and bud production may also occur. 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.