Answer: Unfortunately I can't give you a definite answer based on your description. There are a number of possible causes for evergreen needles to turn brown and branches to look sparse, including cytospora canker, needle casts, spider mites and possibly the spruce aphid. All of these would cause damage without obvious insects or holes. Another possibility is that the plants got too dry at some point during the season, and needles died back as a result. If possible, I would consult with your local county extension for a definite identification of the problem and your treatment options.
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