Hello, We have maples lining the street that have suddenly begun to drop their leaves en masse. The leaves are browning on the trees and falling. Is this due to the dry/wet weather cycles we've had or a sign of disease? The leaves appear to be developing brown spots before dropping .
This looks like a type of foliar disease called anthracnose. This can be prevalent during cool wet springs.followed by warm weather which we experienced this season. You may notice browning along the leaf veins. Anthracnose can affect oak, sycamore, ash, maples, etc. No control is necessary. Rake all fallen leaves to prevent overwintering spores. See our website for photos and more information http://extension.umd.edu/hgic/shade-tree-anthracnose-trees
Thank you! I will share this information with the community.