Answer: The fall webworms appearing now are ugly but they will not damage the tree much because it is the end of the season and the leaves have already done most of their work for the year. Pruning out the branches will work but it can easily and quickly misshape the tree as a result. You can remove them with a stick or open them up so the birds may feast or spray them with Bt (Bacillis thuringiensis) according to the label instructions if you find them unsightly enough to be worth the effort. In my opinion it is a lot of work for something that is not truly harmful.
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