Answer: I think the cedars are actually suffering from a disease called cedar-apple rust. It's a fungal disease that requires two host plants to complete its life cycle -- cedars and apples -- hence the name. I don't think there is a systemic solution to this particular problem.
The description of the gall-forming insects sound like adelgids. Different species attack various species of spruce. The insects are exposed only for a short time. Females lay eggs on buds at about the time buds start to break. They surround their eggs with a wooly substance to protect them. The eggs hatch within 10 days, and as the nymphs feed, a gall forms and eventually surrounds them. They do appear orangey! The galls break open naturally to allow the maturing adelgids to leave, and they in turn lay eggs that will overwinter.
Timing sprays is crucial to control. Since this is a large planting, I suggest that you enlist the aid of a professional arborist. If the solution is a systemic pesticide, they may use products that only licensed applicators are allowed to handle. If you want to try it on your own, consult with your county forester for details on what to look for and what to apply. Your extension service (ph# 908/788-1338) can help you reach a forester. Best of luck!
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