I see a lot of birch and spruce here. I've seen a few here also mention to go to the store and buy oak board. I'd like to use locally available wood. You'd think if inupiat can build a bow with bones and sinew, you could build a bow out of anything. My question is if I am to build of bow of birch, what parameters do i need to follow? 2" wide limbs and 60+" tall? If The reason i bring up eskimo bow is because you'd think one could wrap a bow with enough sinew to make anything work. Is this wrong?