Anthracnose, also known as bird’s eye rot, is a leaf disease that affects many deciduous trees whose leaves are susceptible to the fungus species apiognomonia. The fungus can survive the winter in the tree and to a lesser extent in fallen leaves. Come spring, new spores form and are spread regardless of wet or dry weather. Cool temperatures in the low to mid-fifties during leaf emergence in the spring are a favorable factor for the spreading of this disease. Crabapples, dogwood as well as many fruit trees are susceptible.
Symptoms: include small black dead spots on leaves, dying flower buds, and premature defoliation. The lower side of the affected leaves will have little round pimple-like forms.
More information: Cornell University, Ohio State Extension