#rhytisma

[wildflowers-of-southern-ontario]

Black Tar Spot Rhytisma acerinum Rhytismataceae

It is a fungus that commonly affects sycamores and maples, like in the above photographs. Fortunately it does not have adverse effects on the trees in the long term, but it is still a little unsightly.

Photographs taken on October 13, 2020, along the Etobicoke Creek Trail, Mississauga, Ontario, Canada.