What Causes Brown Spots on Maple Leaves

Maple Tar Spot is caused by one or more species of the fungus Rhytisma. Like many other fungi, Rhytisma has an annual life cycle that includes dormant overwintering. It’s followed by spring growth and release of fungal spores that are carried by wind and water to its host plants, our beloved maples.

How do you treat brown spots on maple leaves?

Maple Tar Spot Treatment Start by raking all your maple’s fallen leaves and burning, bagging, or composting them to eliminate the closest source of tar spot spores. If you leave the fallen leaves on the ground until spring, the spores on them will likely re-infect the new foliage and start the cycle again.

How do you treat maple fungus?

Verticillium wilt Dead leaves will fall to the ground and the soil will reabsorb the fungus, potentially setting off a wider infestation. Treatment: No cure, but some trees can recover with proper care. In severe cases, remove tree, fumigate soil, and plant a wilt-resistant species in its place.