Answer: One easy way to check your spruce for spider mites is to hold a piece of white paper beneath a branch and tap the branch sharply. If there are spider mites on the branch, some will fall onto the paper. They will look like tiny pieces of pepper, except that if you look closely, you'll see them moving. Spider mites are easier to discourage than they are to control. These pests like dry, dusty conditions so simply hosing your plants off twice a week should keep them at bay. They can spread to other nearby plants so hose those off periodically as well. The simplest approach to control is spray the foliage thoroughly with a garden hose or spray bottle. Dusting sulfur can be applied when the temperature does not go over 90 F (hose the sulfur off after a day or so). Special sprays (miticides) can also be purchased, but hose washing or sulfuring the foliage is simpler and quite effective. I'd wait until next spring before removing any damaged branches. The branches may look bare now but there's always the possibility that they will produce new foliage. I'd give them the benefit of the doubt. Best wishes with your spruces.
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