Infected, girdled branches dieback from the tip to the point of infection. Keep trees healthy and prune out infected branches. Leaf spots are usually not serious enough to warrant chemical controls. Once leaves are heavily infected the opportunity for chemical control is lost. Rake up and dispose of infected leaves.
Powdery mildew causes a white coating on the leaves.
Late in the season it may be ignored. When needed, benomyl should give control. Sooty mold makes a black coating on leaves and stems. The fungus grows on the honeydew left by insects. Control sooty mold preventing the build up of insects populations.