Professional Pruning Lopper for Experts Gardening and Farming. Bypass Bypass loppers have blades on both levers that bypass each other to make a clean cut—just like scissors. They are best used to make clean angled cuts on live wood. Using a bypass blade on dead wood can sometimes jam and even bend the blades. Anvil An anvil lopper blade consists of a blade side that pinches wood against an anvil edge to make a cut—like a knife against a cutting board. An anvil lopper is best used on dead wood or to trim back branches before cleaning them up with a bypass lopper.