There are black spots on my maple leaves. Is this a serious problem?

FAQ
Question: 

There are black spots on my maple leaves. Is this a serious problem?

Answer: 

Tar spot is a common leaf spot on maples in the United States.  Several fungi in the genus Rhytisma cause tar spot.  Fortunately, tar spot does not cause serious harm to maple trees.  The damage is mainly cosmetic. 

The severity of tar spot can be reduced by raking and removing infected leaves from around the base of the maple tree in fall.  In most cases, controlling tar spot with a fungicide is not practical/feasible.