1. How to trim 1? Determine the shape: before trimming, determine what shape to cut. Generally, elm has many shapes, such as straight stem, inclined stem, bent stem, cliff, jungle, wind blowing, attached stone and so on. After shaping, pruning can make plants achieve the expected effect. 2. Trim branches: After the shape is determined, don't try to trim it. The first is dead branches, diseased branches and weak branches. Plants that need pruning to avoid affecting the normal growth of plants. Then cut off redundant branches, such as cluster branches, cross branches, parallel branches, reverse branches, top branches, radial branches, opposite branches, vertical branches and other useless branches that interfere with tree modeling. Finally, trim the plants according to the desired shape. It should be noted that the incision should be smooth to facilitate healing. 3. Optimize the details: For the basically formed plants, just optimize the details. Those sharp branches and leaves will be trimmed in a controlled way, or removed by picking buds, so as to avoid the messy and cross branches and leaves of elm trees and affect the ornamental effect. Second, the pruning method of large and small elms is similar to that of large and small elms. Pruning is mainly for beauty, so it is necessary to keep the necessary branches, cut off redundant branches, anti-branches and other useless branches that affect the shape, and keep the plants beautiful. Before pruning, cut off dead branches, diseased branches and weak branches to reduce water transpiration and avoid affecting the normal growth of plants. However, the small elm has strong germination ability and fast growth, and has not yet been finalized. Regular pruning is needed to keep the trees beautiful. Big elms can be pruned regularly.