A frequently Picture of blighting phase of maple anthracnose. Photo from Plant Diagnostic Clinic - University of Missouri observed symptom is the sudden wilting and death of a young leaf, which is often confused with frost damage. The common tree species that we see each year infected with anthracnose are maple, ash, elm, oak and sycamore. The anthracnose fungi that infect shade trees are favored by cool, moist weather. Thus we tend to have more problems with anthracnose on shade trees during cool, wet springs.
Most healthy trees can tolerate an anthracnose infection with little loss of vigor.
However, anthracnose infections can significantly damage seedlings. This disease can also be a problem for trees that have had repeated defoliations or are under other stresses. For these situations, fungicide products containing Bordeaux mixture, mancozeb or thiophanate methyl may be appropriate. Little control will be achieved if spraying is started after symptoms are seen. In most situations, the only controls that are needed are a little patience and a rake.