Thanks guys. I was thinking yellow birch as the wood looks a bit yellow, but had no idea.
Rsp, I have not gotten too many staves from lumber until I started looking for shaft wood. Now I think it is a great source. With a bit of searching I can find a $30-$40 board that I can turn into 4 staves with a single growth ring back. When they are down to stave form it is the same as a good split tree stave but a lot less expensive. I've gotten white oak, birch, ash, and hickory this way so far.
Ed, The shafts turned out nice from the wood too. I may make arrows to match this bow. Kind of cool having a bow and arrows all from the same piece of wood. The arrows I made for this Ishi bow were from this board. Ishi used birch during his time at the museum for some of his arrows.