Disease and Stress Blight City Trees

The American Phytopathological Society says plant diseases and environmental stresses are affecting the health of trees in North American urban areas.

Plant Pathology Professor Daniel Collins of Southern University in Baton Rouge, La., says a number of well-known plant diseases — including Dutch elm disease, dogwood anthracnose, powdery mildew and oak wilt — together with emerging diseases, such as sudden oak death, are threatening the health and vitality of urban trees in the United States and Canada.

Environmental stresses such as flooding, wind damage, drought, pollution and insects also harm urban trees.

Urban trees improve air and water quality, protect watersheds and provide a habitat for wildlife, said Collins. We need to be aware of the wide range of issues that are affecting the health of urban forests in the U.S. and Canada and how we can manage them.

The research will be presented at the Urban Forestry Health Management symposium July 31 during a joint meeting of The American Phytopathological Society, Canadian Phytopathological Society and the Mycological Society of America in Quebec July 29-Aug. 2.