Been there, done that. Lots of good firewood in a trunk of that size. It'll be a bit annoying to split the areas from which the limbs originated because of the strange grain, but it'd be a waste to just roll that into the woods to rot. If you have the right tools for the job, it's not that bad. If you don't, then it will be frustrating as hell. Here's a larger white oak that got turned into firewood. The ability to make full-width cuts with long bars made the process a lot less difficult.