I have a large oak tree in my back yard. The previous homeowners had a wooden octagonal bench built around the base of the tree and filled in with soil. It’s about 2 feet high. Several years have passed, the oak has grown, and the bench has become dilapidated and must be removed or replaced. If we remove it, and the soil around it which has surrounded the tree for many years, will there be irreparable damage to the tree/bark? Should we remove the bench but leave the soil in place? My husband seems to think the tree would not survive if this soil is removed; that we must build a larger bench and fill it in with more dirt. I would like to get an expert opinion on this before we go to that expense, as the bench has been pretty to look at, but has never been used as a bench by our family.