I know this sound fantastical and maybe it is or just something Kool to ponder for a moment? Lets ponder that the Devil's Tower was a huge tree stump, so what would a stump of a huge petrified tree look like anyway? Here is a link to a petrified wood stump table, notice the blocked structure. This is also the same structure on the Devils Tower, only scaled up to the size it is. Real? I'm not sure but hey I think it could use more investigation, and Its fun to ponder if its not no lose. The outer bark has been eroded or removed, could have been cut down? Tree of Life?
Link to Petrified stump Table: [www.bing.com]
P.S. Sorry to all I haven't been on and replying, been busy and these are my worst months pain wise with all this cold.