The first mistake you made was cutting it off close to ground level. If you would of left 3-4 feet remaining it would be a lot easier to push over or pull out. Some rope and a couple of pulleys and a truck or small tractor would rip it out.
If you want to burn it use charcoal. Cover it with a bag full, light, and go back the next day to see how much burned .


My biggest fear is when I die my wife will sell my guns for what I told her they cost.