Ash, Oak, Maple, and Sycamore trees, as well as others, are at risk for a fungal infection called Anthracnose. This infection creates blackened and broken sections of the tree by attacking the buds, branches, leaves, and twigs in the spring or fall. Infected leaves from previous years show the first signs of infection with small black spots. Wind and rain spread the disease to nearby trees when spores are released, which can result in the fungus visibly affecting the foliage and fruit. These primary infections can then create secondary infections that will carry on throughout the growing season, specifically in wet periods.
The best form of treatment and prevention of Anthracnose is to increase tree vigor in susceptible species. In some cases supplementing with a fungicide early in the growing season is warranted, but not always. Detection and maintenance are key to keeping Anthracnose at bay. Irregular patches of distortion or discoloration in leaves can tip you off to an infection. Leaves may also drop earlier and have blotched areas along their veins.
Properly timed systemic fungicides may be required for trees that have a history of the Anthracnose infection to prevent worsening and spread of the disease. This disease tends to be much more prevalent following a cold, wet spring. Without treatment, infected trees will begin to lose their leaves during the summer months, which can drastically reduce the tree's health and create susceptibility to a range of other infections. They normally send out a second set of leaves which uses up a great deal of energy.
Contact Plant Health Solutions for proper diagnosis and to develop a treatment plan.