Pollarding – refers to cutting the branches of a tree to contain its size. Experts suggest starting this process when a tree is young and continuing once every two years. Reduction – is a technique of tree trimming that involves shortening the branches selectively. It also helps to reduce the spread and height of a tree and curb excessive growth sprouts. Topping – is a process that should start when a tree is indiscriminately cut back to stubs. This method is not usually preferred because the result is unpredictable.