Pruning can improve the health, productivity and appearance of your trees and shrubs. But improper pruning can destroy the shape of your plants and also cause more harm than good. Following a few simple guidelines can help make the right decisions when deciding what to prune out of your trees and shrubs.

First, remove the three D's, dead, diseased or damaged branches. Also prune out branches that cross each other. Trees do best with only one leader, which is the main upright trunk of the tree. If there is a branch competing to be the leader it should be pruned.

Understand your plant's shape. Is it natural creeping, mounding or upright? Visualize what shape the mature plant will be and prune out branches that interfere with the natural shape.

Remove suckers. Some plants, such as glossy black chokeberries tend to send up suckers which are new shoots from where the stem meets the root. Carefully cut out the suckers which interfere with the shape of the plant.

Timing. Generally it is best to prune plants in late winter or early spring before the new growth starts. However, for spring and early summer blooming shrubs and trees, such as lilacs, wait until after the bloom and then trim. This will help you to avoid cutting off the current buds.

In pruning it is best to recognize your limitations. For tall trees or high branches you may need to call a professional arborist. Also, if you have any questions on what or when to prune make sure you do more research before getting out those clippers.