As trees around town finish putting out their leaves this spring, we sometimes get calls about splotchy, shriveled leaves on customers’ trees. This can be an alarming sight, as these leaves are fresh after the tree has been dormant for the winter. The issue is called “Anthracnose”, and luckily it’s not usually much of an issue at all.
Anthracnose is a fungal disease that affects the leaves of shade trees. It can cause leaf spots, curled and shriveled leaves, and even premature leaf drop. Typically anthracnose is prevalent during a cool, wet spring. Like a lot of fungi, this type of weather is ideal for spores to form and spread.
While anthracnose can affect multiple species of trees the fungus affecting a tree is often species-specific. For example, if an Oak in your yard has it, only other Oaks will be susceptible. In Richmond, we frequently see Sycamore and Oaks showing symptoms of anthracnose.
The good news is that anthracnose really isn’t much of an issue. Most of the symptoms are more of a cosmetic problem than anything, and trees typically can handle the loss of healthy foliage. If your tree has a form of anthracnose, there are a few steps you can take to help mitigate it. Redirecting irrigation away from an affected tree can help with too much moisture. In the fall, dispose of leaves at the base of the affected tree, as the spore can lay dormant on the tree’s fallen leaves. Finally, if the affected area of the canopy is small enough, pruning out those affected limbs can help slow the spread. On rare occasions, applying a fungicide might be necessary, but this is typically a severe case.