Answer: I am assuming these are the fortunei type of euonymous. Based on your description I am not sure what is happening, but some types, such as "Manhattan," will lose even more leaves during the winter than usual following a dry fall. It is also possible that they are suffering some type of pest problem which is only now becoming apparent. You might want to take some samples to your county extension (285-4630) for a more specific identification of the problem. I'm sorry I can't be more helpful.
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