You may have noticed that some Sycamores have lost many of their leaves. Are they going to be OK? The short answer is, probably.
Sycamores, Platanus occidentalis, a native tree in Ohio which tends to flourish along stream banks but is adaptable to many locations, have lost their leaves (some but not all).
Sycamores, which have a leaf that looks like a maple
but are alternate along the stem, are known as a large tree that can have a mottled bark, giving it an interesting winter interest.
They are known to be susceptible to anthracnose, which can cause spring defoliation, and can also cause witches broom in the twigs. Even though the trees will look bare in the spring,
they tend to leaf back out this time of year. As they proceed through the rest of the growing season, the trees will photosynthesis enough to support tree growth and health, with little long-term effects.
Dr. Jim Chatfield published a great BYGL article on anthracnose:
https://bygl.osu.edu/node/1305
The one drawback of anthracnose effects on branches is they can form witches brooms on the ends of branches.
But the trees should, for the most part be fine.
If you are looking for a resistant variety, London Planetree, Platanus x acerifolia, has shown to have good resistance to anthracnose infections.
So, your naked Sycamores should cloth themselves soon enough. Not to worry!