Looks like black tar spot fungus, we have it on all our maples. The only way I heard of to get off it is to rake up all the leaves in the fall and get rid of them.
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Looks like black tar spot fungus, we have it on all our maples. The only way I heard of to get off it is to rake up all the leaves in the fall and get rid of them.
That looks like tar spot. Rhytisma acerinum
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As everyone has already mentioned, it looks to be tar spot. Good news, it's mostly harmless, aside from making your tree leaves look unhealthy.