Answer: There is a disease called anthracnose that affects sycamore trees and that might be what killed one of your trees. I can't diagnose the problem without inspecting the tree but the early symptoms include the failure to leaf out in the spring. It's also possible that your tree was stressed over the winter months and is simply slow in leafing out. You may want to contact your local cooperative extension office for help in diagnosing the problem. If there are any steps you can take to help your tree, your extension office can provide guidance.
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