There could be infection spreading under the bark. Sooty Canker is one possibilty, black powdery fingus spreading under the bark. Have an arborist look at it. May be able to remove infect branches, tr ... read more
When sunken living rooms were the rage, many of them were below grade. Later on some decided that being on all one level was more desirable so it became popular to fill them with concrete to the level ... read more