A year ago I cut down a yellow birch tree thinking it was the best wood option I had (now I've discovered that I have access to sugar maple). Yellow birch grows really straight and quite clean, so I got some nice staves out of the tree. Since this is my first bow not built from a board, and I didn't know what to expect from yellow birch, I decided to make a nice safe bow. It's 66" long, 2" wide at the fades and 1/2" at the nocks. It is parallel to about mid-limb. It pulls 40# at 28". I decided to keep this bow really simple; no tip overlays, no handle lamination, no backing, not even an arrow shelf. I also didn't do any heat bending, so the bow is a little twisted, but the string lines up through handle so it works fine. As it turns out yellow birch bends real easy with dry heat, but I'll save that for when I post my other bows. After putting some fancy finishes on a few bows it was kind of nice to make a bow that was just a single piece of wood. The bow has 2-2.5" of string follow, but the stave was deflexed at least an inch to begin with, so it really didn't take too much set. I've yet to have a yellow birch bow break on me, and I get the impression that it's more likely to take set than explode. All things considered I think it's a fairly decent bow wood. I'm going to try to make a yellow birch bow in the 50lb range next (all of my others have been 40# or less) so we'll see how it handles that.
Extra information and pictures are available here: diydudes.com/a-simple-yellow-birch-flatbow-bow-4/
And here's a quick video of the bow in action:
https://www.youtube.com/watch?v=4wPaxUKCykM