Answer: There are many different possible causes for your tree to look as though it is drying out. Unfortunately it is very difficult to diagnose long distance because it could be several different insects, different diseases, or even a root problem or an environmental problem. I would suggest you work with your local county extension to determine the cause and once you know that, figure out how to treat it. If it is something that needs a chemical control, they will have the most up to date recommendations on what to use and how/when to apply it for best results. It is almost always better to treat these types of problems as soon as you notice them, so don't wait. Good luck with your topiary!
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