Could you provide some photos? It may help us to determine if it is a normal needle drop as all evergreens drop old growth in either spring, fall or throughout the year. Spruce needles tend to turn yellow first (similar to pine) but you may not have noticed it. Photos of the canopy, root flare area at the base of the trunk, and up close of the needles could help. Make sure they are at least 1MB in file size so we can zoom in clearly.

If could be due to drought and heat stress this past summer/fall and last summer as well. Many large old trees are showing some stress symptoms from these extreme weather conditions. It could also be a response to some root damage from the excavation. 

If you can supplement water in times of drought that would be beneficial to help the tree manage the root loss. Even if you had recent rain on Sunday, with the ground being so dry, it would be beneficial to water deeply until the ground freezes. 

You can refer to our Watering Trees and Shrubs page for more details on how and when to water trees.

Let us know if you have trouble uploading photos. 

Emily