Rhytisma

Tar Spots of Maple

  Tar spots of maple, caused by species of the Rhytisma fungus, are prominent now, although mostly not as severe as in wetter summers. There are two different tar spot diseases of maple, one affecting silver and red maples, caused by Rhytisma acerinum, resulting in dense, tarry spots that truly reflect the “tar” spot name (first picture below).
Published on
Authors
Jim Chatfield