People have often asked 'can I burn 2x4s in my woodstove'? The answer is alway, 'yes of course, but not exclusively, the stove will overfire because the wood is too dry.' But what if that was the only wood you had? There must be a stove, or a type of stove, that could handle this problem. Related to the overfiring problem - and also I big problem - would be the need to fill the firebox too often... so I guess you need something that had a big firebox, and that could burn slowly... and also had some margin of safety. I just ask because I'm currently living in a place where this is the case - lots of free scrap lumber, absolutely no firewood.