Maple trees with spotted leaves

Asked July 16, 2019, 9:46 AM EDT

I was wondering about some maple tree's that have spotted leaves, as we have 7 or 8 trees that have spotted leaves. the question is " is this normal or are they infested with some sort of disease?" . I have included 2 leaves from 2 different trees that show the spots in question. Should these trees be removed?

Mecosta County Michigan maple trees spotted leaves

1 Response

It appears that your maple leaves are infected with a very (very) common fungal disease called Tar Spot.
  • Description: Tar spot is an ugly but mostly harmless disease that strikes several maple species. As its name implies, tar spot disease looks like big black tar spots on the top of the leaves.
  • How it spreads: Infection typically begins in early spring and continues into the early summer. The fungus is able to take hold when there are prolonged periods of wet weather that prevent the leaves from drying off. Leaf spots start out yellow and evolve into a dark, tar color.
  • Prevention: Treatment is generally not recommended for tar spot because it is usually not a serious problem; however, raking up fallen leaves will keep tar spot at bay.
The information in the link below will provide additional information.