KC Gardens

Trim your trees before the leaves return

Make the cut at the branch collar so that it heals properly.
Make the cut at the branch collar so that it heals properly.

Spring is just a few short weeks away. As temperatures warm up and days get longer, buds will begin to swell in preparation for the growing season. One activity best done before the buds pop is pruning trees. Late winter to early spring is the ideal time to make the necessary cuts to improve the health of the tree.

Pruning at this time of year has several advantages. Most important: The trees have no foliage, making it easier to see the structure and where to make the cut.

Also, during the dormant season there is no insect or disease activity, so the wound has a chance to seal over before those dangers arise.

Lastly, once spring growth occurs, the result is robust growth for a healthy tree.

It’s important to trim in the right place to promote quick healing. The cut should be made just beyond the area called the branch collar. The collar is the raised ridge of bark tissue. It follows the growth angle of the branch, as should the cut. Making the cut at this area stimulates the cambium layer to produce new tissue to cover the cut. This keeps out wood-rotting organisms and harmful insects that can transmit disease.

Deciding which branches to remove can be difficult even for the skilled pruner. Begin by removing dead, damaged or hazardous limbs. Dead wood provides no benefits, and damaged wood eventually dies or introduces decay. Hazardous limbs, such as those hanging too low, should be removed to prevent them from injuring anyone.

Young trees need the most attention. Many potential tree defects can be prevented in the first few years of growth. Unfortunately, many times theses simple cuts are neglected until it is too late.

Double Leader Pear Tree
Trees with double leaders are vulnerable to breaking in wind and ice storms. Adele Wilcoxen

Many young trees have a central leader or main growing stem from which the tree develops. However, a double or forked leader often occurs, and these become weak areas as the narrow crotches compete for the same space. These narrow crotches are the first to fail in a wind or ice storm, and when this happens at an old age, the tree usually needs to be removed.

It’s easier to fix the double leader problem when the branch is finger- to arm-size. Simply remove the one that appears less upright, attached to the main trunk below. Or, when in doubt, take off the one on the north side of the tree.

Tree species prone to double leaders at an early age include oaks, maples, pines and spruce.

Do not apply wound dressings to the cut surface; they do not help the tree heal. Instead, they can trap moisture under the layer and increase the chance of rot and decay.

Don’t be afraid to prune, as a few simple cuts can keep a tree vigorous for years.

Dennis Patton is a horticulture agent with Kansas State University Research and Extension. Got a question for him or other university extension experts? Email them to garden.help@jocogov.org or visit KCGardens.KansasCity.com