The sycamore is one of the most common trees grown in North American landscapes; yet, the stately tree can succumb to a fungal disease, anthracnose, causing it to lose its appeal. Anthracnose often attacks sycamore trees in the spring, quickly wilting new leaves that are emerging. Twigs and branches of sycamore trees are also affected by the disease, developing cankers which will produce spores the next spring and re-infect a tree. The weather plays a large role in determining the severity of the disease, as anthracnose rampantly develops under wet conditions where the temperature does not reach above 55 degrees. With diligence, however, anthracnose can be treated.
Apply a fungicidal spray in the early spring when buds begin to swell. If a period of rain occurs following the application, it may be necessary to re-treat for the next one to two weeks.
Collect and dispose of fallen leaves and twigs.
Use pruning shears to prune any infected twigs that remain on the tree. Discard the twigs.
Continue a watering regimen throughout the winter (in the absence of snow) to prevent the likelihood of a tree becoming infected. Sycamore trees can be weakened in the winter, increasing their risk of disease.