Cool, wet weather has reared its ugly head, resulting in our first reports of anthracnose fungal disease on shade trees this year. Common on sycamore and maple, the disease can also infect oak, ash, elm and others.

On older leaves, look for brown areas that tend to show up along the major veins on the leaf. Younger leaves may actually wither and turn black. If the leaf stems (petioles) are infected, you might even see leaf drop, even as the leaves look perfectly fine.

If the disease is severe, leaf drop can result in complete defoliation – but don’t panic. If your trees are healthy, they should leaf out again in a few weeks with the overall health of the tree relatively unaffected. Trees have plenty of time to produce new leaves and make the energy reserves needed to survive the winter.

Because anthracnose seldom causes significant damage to trees in Kansas, chemical controls are usually unnecessary. Since the fungicides do not cure infected leaves, applying fungicides now will be of no value.