Yup, the "Australian Pine" - Casuarina Equisetifolia is serious stuff. I once cut a 3/4" sapling and made a bow from it a week later. It is still shooting about 3 years later. Don't really think I ever posted it...but it's a real stickbow about 65" long or so. It looks like a toothpick but pulls 50# at 28". I still like Osage better for the sheer beauty, bending properties, humidity resistance, general 1st class performance properties, etc., etc., but it has it's own qualities. I need to get out and cut some new large diameter good pieces for testing, like this. I'll work on getting some cut soon and bandsawing it in pieces. It's gotta be the nastiest wood on the planet to split because it is the ultimate in interlocked grain. I promise, when I do, a stave has your name on it.
And, as far as firewood goes, I'm thinking that the Casuarina puts out more heat also. From what I've read it's one of the hottest burning woods in the world. It just doesn't burn as long as other woods...which makes sense...
Anyhow...I digress.