We’re seeing an extraordinary amount of maple trees inflicted with tar spot – a fungal disease characterized by black, tar-like dots on the foliage. Emerging in spring as little yellow pinpoints, the spots darken and enlarge later in summer, eventually resembling black tar spots. The good news is, tar spot is primarily a cosmetic nuisance. Tar spots may cause premature defoliation, but are not known to kill trees.
For more detailed information, read a FACT SHEET on Maple Tar Spot by the experts at Michigan State University by clicking here.
TIP: Tar spot diseases are best managed by raking and destroying fallen leaves because the fungi overwinter on leaves.