Am getting ready to see a friend's hemlock I treated several years ago (5) for HWA and now he wants me to look at the tree due to it turning brown in the interior but with new growth on the ends. Could be anything from natural needle loss to Phytophthora since they have had issues with drainage on some other plants. So anything else I need to look at? I will take some pics if I am unable to diagnosis the issue. I usually do not have to treat any hemlocks beside for HWA.