Rake and dispose of the fallen leaves to reduce the chance of infection in the following season, and maintain vigor of the trees with adequate water during dry periods and fertilization in the spring. Since this disease is usually not a serious problem for the health of the trees, chemical controls are usually not necessary. Purple eye, Phyllosticta. Small grayish-tan spots with purple borders are scattered over the leaves. Tiny black dots in the spots are fruiting bodies of the fungus.
Control is as for anthracnose.
Tar spot, Rhytisma acerinum. This fungus produces raised black spots that look like blobs of tar on the leaves. It is unsightly, but not serious. Tar spots are most prevalent on maples. Raking and disposing of fallen leaves is sufficient for control.