Working with rough-sawn lumber a lot, means time with the jointer — and push blocks. However, the rubber faces of standard push blocks wear out pretty fast against rough boards, and they don’t grip the wood all that well. If you've experienced this, try using truss repair mending plates. The sharp points on the plate grip the board and never wear out. Just attach the plate by drilling some small holes and screwing it to the push block. It's an easy and inexpensive way to get a grip on those uneven workpieces.