Birch?

BTU's? This is for River Birch (Betula nigra) - NOT Black Birch (Betula Lenta)

I have a little over a cord of River Birch coming to me for a very, very low price...delivered to my driveway in rounds (for next year!). How many BTU's does it have? I can find almost every other birch, but not River. Anyone out there with some knowledge you can throw my way - maybe someone who has used/uses it?

Thanks for the help gentlemen! This site has been invaluable to me in the last year. All of your helpful input goes farther then you realize!

Thanks for the replies. I only see where River Birch is called Black Birch, however it's not the "true" Black Birch. I don't see anywhere where Paper(bark) Birch is called River Birch. I do see where Paper Birch it's called White Birch (http://en.wikipedia.org/wiki/Betula_papyrifera). All of the Birch are at least 20 BTUs and up - which isn't too bad. I just like learning, so was looking for some answers...somewhere out there...Thanks!