News in Cortland NY

Sycamore Tree Anthracnose Update

Several Sycamore trees in Cortland are suffering from anthracnose, a fungal outbreak that is weather-related. The good news is that anthracnose is a leaf disease caused by fungi that are active in cool and wet weather. While the fungus can highly disfigure leaves on susceptible trees and even cause leaf loss, this does not affect the overall health of the tree.

Since this disease will stop as the weather becomes warmer and drier, there is no need for control measures in most cases. Even if defoliation occurs, the tree can put out a second flush of growth under warmer and drier conditions that prevent reinfection by the fungus. To help reduce the infection level the following spring, remove and discard the leaves from a diseased tree in the fall -- or compost them properly.

Sycamores aren’t the only trees susceptible to this fungus – in fact it can affect many other shade trees. Remember, the good news is that this outbreak is due to Cortland’s recent cool and wet weather and isn’t a sign that the trees are dying.

For more information, you can visit the Cornell Cooperative Extension of Monroe County’s horticulture website at www.cce.cornell.edu/monroe/horticulture/factsheets/fs19.htm or find a copy of Hudler, G. W., W. A. Sinclair, and W. T. Johnson. 1985. "Anthracnose Diseases of Trees and Shrubs." Cornell Tree Pest Leaflet A-2.