Mature Maple trees and Hornbeams heavily losing leaves
Just this week our mature, 35 year old Maple trees have lost almost 20 percent of their leaves and our 25 year old Hornbeams have the same issue. We noticed a lot of brown and gray spots on the fallen tree leaves. Is this the result of the earlier drought and then the heavy rain causing a fungus outbreak or blight? Given the early leaf loss, will the trees be healthy enough to come back next spring? The Hornbeams are usually late to lose their leaves. We can send a picture of leaves, if needed.
Howard County Maryland
We have had several reports of leaf spots and defoliation on maples. This has been due to the excessive rain we have had. Please send us photos of the whole tree, around the base, and affected foliage so we can see what you may be dealing with.
It looks like your tree has symptoms of a fungal leaf spot disease, possibly phyllosticta and/or anthracnose. https://hgic.clemson.edu/factsheet/maple-diseases-insect-pests/
The excessively wet weather this year has been favorable for the development of a lot of fungal diseases and we have seen several reports of this symptom on maples in particular. At this time in the season, there is nothing you can do. There is no cure for the symptoms you see. By this time of the year, trees have been storing up sufficient food reserves and leaf loss will not cause major harm to an otherwise healthy mature tree. Clean up the leaf matter under the trees to help reduce fungal inoculum. Monitor the trees early next season. If you see any branches in the crown that do not leaf out next spring, or if there is any visible damage to the trunk (we don't see any in your photo), that would be of greater concern. You have the option to consult with a certified arborist if you would like a professional to conduct an evaluation of your trees on site. You can find a certified arborist by using the "Find an Arborist" section of this website.http://www.treesaregood.org/