Ideally it should be sinew backed, I know some have made it unbacked, but they are long and apparently shoot sluggish. I have only made
a short sinew back juniper bow, its 54" long. It will be way thicker than you might think. It is extremely soft, considerably more soft than yew. So when you rough out the stave, maybe even start the limbs an inch thick, and even thicker if you are making a longer bow. It works very easy, just be careful around the knots.