Hello. I have several large Hemlocks off my driveway that help with privacy. Its my first year living here and dont know if what I'm witnessing is normal or if there's an issue. A large majority of the Hemlocks needles are turning yellow and brown and falling. On close inspection of the needles, I dont not see signs of anything unusual like bugs or scales. I've provided a few close ups. Basically, they start turning yellow, then brown then they're on the ground. The solid around them is moist but not wet. I have seen a lot of Chipmunk tunnels around a few of the trees.
Would someone be kind enough to educate me as to what may be happening to these beautiful trees? They seem so healthy a couple months ago and now I dont know if they're dying????