Diseased Maple Tree?

[BlueCrab1027]

I have four beautiful Norway maple trees that I planted about 15 years ago. I've never had any problems with them. This year, however, one of the trees has developed dime-to- quarter size blotches on the leaves that appear to be areas of premature rot. There has also been considerable leaf drop. I can see no evidence of insect infestation. I'd be grateful for any advice as regards spraying or systemic treatment or any other opinions. Also, is there any chance this may spread to my other trees and, if so, what can I do?

 

[Treeman14]

The blotches are probably tar spot, a fairly common disease among maples. Unless it is really infesting the entire tree, no control is necessary. The leaf drop is most likely not related. Possibly girdling roots, verticillium wilt, or manganese deficiency(if yellowing precedes leaf drop).