Answer: This could be due to moisture stress or more probably an insect problem such as spruce spider mites this past spring, especially since it is only on one side and the needles are falling now. Here is more information about this pest. You may need to cut and paste the complete url into your browser to make it work correctly.
I would suggest you contact your local Penn State cooperative extension for a more specific diagnosis. If a chemical control is needed, they can give you the most up to date information on what to use and how/when to use it for maximum results. In the meantime, water as needed to keep the soil evenly moist like a wrung out sponge. (Not sopping wet, not dried out.) This will help minimize stress on the plant. Good luck with your Alberta Spruce!
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