A friend gave me an elm trunk last summer, about 8" in diameter. I split it then and it had a 90 degree twist. i.e., the back at one end of the stave was fully perpendicular to the back at the other end. To potentially get something out of it, I cut a few straight staves out of it with a circular saw. These then have a continuous non-violated ring on the back, but obviously the grain runs off multiple times. DO you think the interlocking grain of elm would hold for a selfbow? Alternatively, a fabric backing would probably work.
Dave