Question
My Maple tree has developed large dark Brown spots on it's leaves. These spots are hard to the touch. The tree has been droping many of its leaves. The tree is a maple Approx. 30 yrs old.
What do you suspect is the problem ?

Answer
These are leaf spots caused by a fungus. These normally infect the leaves late in the growing season and cause little health problem to the tree. They can cause the leaves to drop prematurely. A tree this large would be hard to apply fungicide to all the leaves and in my opinion is not needed. Hwere is a web link that will give more information on leaf spots.   http://ohioline.osu.edu/hyg-fact/3000/3044.html