Q: I have three sugar maples in my yard, planted in 2001. Last year they were all green but no real growth. This year two aren’t doing well. They have leaves with dark spots on them.
A: Well, I have bad news and good news.
The bad news is that you don’t have sugar maples. The leaves in your photos are those of silver maple, a distinctly inferior tree. I do not recommend it for most landscapes because its limbs are weak, causing large- and small-sized ones to frequently fall.
The good news is that the disease spots you are seeing on the silver maple rarely damage it. The tree is susceptible to numerous diseases: tar spot, phyllosticta leaf spot, bacterial leaf spot, etc.
Leaf spots are common on many trees at this time of year but though they are disfiguring, they are rarely fatal.
Leaf spot on silver maple