Given ideal draft, seasoning, split size, stove operation, etc., is there any real difference in the stove temps you can achieve between hardwood species? If so, is the difference reflected in BTU ratings, or does high-BTU wood primarily just make just a longer-lasting fire? I have an undersized stove out of which I need to coax the best heat possible, and I'm wondering whether it would be worth the effort to try to find a supplier who would agree to sell me just the high BTU species plentiful around here (mainly shagbark hickory and black birch) or whether the more usual mix of rock maple, soft maple, beech, etc., that I'm using now is giving me the best I'm going to realistically get. My stove cruises easily at 400, but I can't get it to 450 but once in a while for a fairly short period (like opening the primary air on a big bed of red-hot coals), and I've never managed to get it above that, despite using 4-inch splits and smaller. A consistent 400 keeps me from freezing to death right now, but I think I'm going to be mightly chilly when serious winter temps come in if I can't get the stove above that for more than the very occasional brief burst of enthusiasm.