Answer: Without knowing what the insects are, I won't chance suggesting a control remedy. Spruces can be sensitive to sprays with an oil base so rather than using a chemical spray, why not try to dislodge and discourage the insect pests with a strong stream of water from the hose? You can repeat this as often as necessary to rinse the pests away. The webbing might be evidence of spider mites. These pests like the innermost parts of trees and shrubs where the area is dry. Hosing down your spruces will rinse them away and repeated applications of water will keep them from taking up residence. You can capture a few of the pests on the branch tips and take them into your local cooperative extension office, Master Gardener clinic, or well staffed nursery for positive identification. Helpful folks there can suggest control remedies. Good luck with your spruces.
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