Question
I am planning to build a raised bed in a circle around a 20-year-old maple tree. It will be about 14 inches high. Do I need to put something around the trunk of the tree to protect it from the new soil build-up?

Answer
Hi Ellen, Yes, you do not want soil, mulch or anything to come in contact with the trunk.  You set yourself up for disease and/or insects if the bark stays wet.  I hope this is just a small bed around the trunk.  Covering a significant part of the rootzone with even 2" of soil can kill a tree and it's a long slow death over several years. If it's only 8-10 feet wide, I'm not concerned.  Jim