The hole was much smaller before. It's getting bigger & more bark areas around it are cracking now. The hole & around areas are dry to the touch. Tree is 9 or 10 years old. It grows slower for it's much smaller than other trees, which are different types - a cherry and a crabapple, all similar size when planted years ago together.
Anyone has any idea about the causes, effect, and any solution that can stop it from getting worse?