Yes, what Pat said, season it for a year. The stuff likes to move around a bit as it dries. I was making a paddle bow out of some one year and had cut out and pretillered the wood before putting on the sinew. Everything looked good. I put it in the corner while I pounded out my sinew for a few weeks and when I went back to it, one of the tips had moved completely out of string line. Luckily I made it a bit wider and longer than need be, but it kept on moving even after this and now it is unusable. I remove the bark now, stave it out into thicker staves and let it season for at least a year. I write the date on the top just to be sure I remember when it was cut. It'll move, but after it goes through a few months of dry weather it stabilises. You can use mulberry for just about any bow design like osage, but, the plus is that it is lighter than osage. Loves a heat treatment too. I'm using white mulberry, so it may be a bit different than the red you guys have.