Hi, First of all, let me apologize for the slow response. Our Garden Doctor program has been rebuilt and out of action for about a month. Anyway, it's always difficult to remove a beloved tree, especially an oak or maple. You can grow anything that pleases you around this trunk. I suggest you go to our Plant Encyclopedia on this website and do an Advanced Search in order to get a planting list. Also, be aware that there are products you can buy at garden centers that you sprinkle over the tree trunk to help stimulate decomposition.