Over the past 3 years or so we have seen Tar spots (a fungus) appearing on certain varieties of Maple. Red and Norway Maples seem to be most commonly affected. At first the situation wasn’t too prominent, but it seems to be getting worse. This fungus appears as the name implies, as spots of ‘tar’ on the leaves.
In the above photo you see a single leaf with some spotting that isn’t too badly damaged. But look at the dual leaves. The fungus is much more severe. On the Maple that these dual leaves came from, the leaves are all dried out and falling from the tree. This has been going on for several months.
If your Maple is exhibiting these symptoms, and damage is severe, you might want to consider having us treat the tree this Spring. If damage is minimal at the present time, don’t worry about it too much. Up until now we have never treated for this fungal disease but it seems to be accelerating to the point that you may want to consider treatments going forward if your tree is being severely affected.