Tree and Shrub Pruning by Tony Wendland

There are many reasons to prune trees. Trees in an urban setting may have low hanging branches obstructing vehicular or pedestrian traffic. They may be too close to power lines, obstruct views or daylight, or may be damaged by wind or ice storms. Many times they have poor branch attachments, co-dominant stems, or are too close to structures on the property. These are the most common reasons pruning is performed.

It is best to begin pruning trees for proper structure at a young age, many nursery grown trees are pruned for shape, not structure, which may cause structural problems, if not resolved at planting or soon after. Trees in an urban setting require much more attention than those in a forest, which have developed naturally. Most urban trees have a target, meaning they could damage property or people. If they fail, failures can occur over time or suddenly depending on the type of problem at the root of the failure. As trees with structural defects mature, the likelihood of failure increases without corrective measures, such as single stem development or reduction or removal of poorly attached branches.

Trees should be evaluated on an individual basis by an ISA Certified Arborist to determine if any pruning needs to be performed and if so, what. Pruning should only be performed by a certified arborist, trained in developing proper structure and removing hazards. Proper pruning cuts are very important. Determining where cuts should be made to reduce branches plays an important role in the future health and beauty of your trees.

In contrast to trees, shrubs are pruned for shape, not structure, but there are still considerations that must be addressed when pruning. Timing is generally more critical because shrubs are highly valued for their flower and fruit production. Many times they are pruned too early or too late, removing buds which would have produced flowers and/or fruit. There is seldom a good time to prune, but for shrubs which bloom on old wood, pruning after flowering is appropriate. For shrubs which bloom on new wood, pruning can be done before or after flowering. Most shrubs flower on old wood, but it is very important to know what type and variety of shrub you are dealing with to take full advantage of their natural beauty.

For more information about tree pruning or finding a certified arborist in your area, go to or or