What inconsequential problems affect maples?
• Tar spot – This is a fungal leaf disease occurring on Norway, red and silver maples. Early light yellow-green areas later turn into black, raised, tar-like spots on upper leaf surfaces. Damage is ugly, but usually only cosmetic. Raking up and removing infested leaves reduces infection. • Powdery mildew – Here is another fungal leaf disease. It shows up as a thin layer or patches of grayish white powdery material. Infected leaves may turn yellow and drop early. A cosmetic problem only. • Maple gall mites – These tiny mites produce very visible warty or spindle shaped galls on the leaves of maples. Usually noticed in April and May, they can be very unsightly. This is a cosmetic problem that does not affect the overall health of the tree. Where can I get more information? Miller, H. C., and S. B. Silverborg. 1973. Maple Tree Problems. Syracuse NY: SUNY ESF. (To order, call 315-470-6644) George Hudler, 1984. Diseases of maples in eastern North America. For other information, advice and h
