I would never back a good piece of osage,dont need it,,I work in osage every day,, I am doing classes all over the country this year,, and the biggest problen I see with new bowmakers,, is being afraid they are going to mess up,,you will mess up,,the sooner you get it out of the way, the sooner you can move on,,,and most time the first layer of heartwood,, will have some sapwood blended in with it,,I usually remove first layer of heartwood off just to get 100% heartwood,,If you can try to get to one of the good selfbow get togethers,,, ojam. mojam,tn classic, or find some near you that makes selfbows,,,lots of good bowyers in tx