When I put a sample of a mostly dead branch under a low powered microscope, I saw that it was teeming with appeared to be some kind of spider mite. If these are spruce spider mites you might try using Cythion, Resmethrin or malathion. Dormant oils will help control the mites but have been known to take the blue color out of the plant. Gibb, Entomologist The information given herein is supplied with the understanding that no discrimination is intended and no endorsement by the Purdue University Cooperative Extension Service is implied. Any person using products listed assumes full responsibility for their use in accordance with current direction of the manufacturer.
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