When you need to cut off a dead tree branch you might think you can just hack away until it falls off, but properly caring for you trees requires a little more finesse. In this video from This Old House, we learn how to prune a branch without damaging the tree. If you try to cut directly through the top of the branch, as seems logical, the weight of the branch might end up snapping the limb without a clean cut. That can rip the bark in a way that will make it difficult for the tree to heal. As Roger Cook demonstrates in the video, it's better to start about 30cm away from where the branch meets the tree with an undercut that goes about 1/3 through the branch. Then, several centimetres further out, you cut through the top of the branch until it snaps off. Now with the majority of the weight gone, you can cut cleanly near the base of the branch without any unexpected breaks. Watch the video for the full arboreal rundown.
How to Hand-Prune Trees [This Old House via YouTube]