A buddy of mine made a nice D bow from an osage that I cut several years ago. 
It was two or three rings of sapwood and a little heartwood on the belly. He dressed it 
up a little with a horsehair tassel on the upper tip. 
I was surprised at how little wood it takes to make a hunting weight bow,,, as this bow 
wasn't an inch wide and drew 50# or better at 26". 
He ended up giving it away........wish he had given it to me