Before pruning, you need to identify parts of the trees you are about to prune. This message describes the branch collar, the branch bark ridge, included bark, and where to make your cuts.

The branch collar is the wrinkled or swollen area around the branch where it attaches to the trunk or another limb. When pruning, the final cut should be next to the branch collar. The cut can go slightly into the branch collar if necessary. However, do not cut off the branch collar. Doing this often results in decay. Leaving too much of a stub is also harmful. Decay may set in before the tree has a chance to grow new wood.

The next area to identify is the branch bark ridge. Look where the branch connects to the tree. The ridge looks like bark pushing up from the topside of this attachment. Do not cut into the branch ridge. Begin your cut to the outside of the branch bark ridge. If there is not a branch ridge, there may be what is called included bark. Branch or stem unions with included bark are usually weak unions, and are more likely to break in wind, snow and ice storms. Prune one of the branches off. This is best done when branches are small.

The wound sealing done by the branch collar happens quicker if the cut is smooth and clean.

When removing large branches, make three or four cuts. Make the first cut on the underside of the branch about 18 inches from the trunk. Undercut one-third to one-half way through the branch, stopping before the saw binds. The second topside cut should be made 20 inches from the trunk. This cut cuts all the way through the branch. The third cut removes the stub by cutting next to the branch collar.

Do not prune oak trees in April, May or June. Also don't prune them when March has unusally warm weather. During these times, open wounds leave these trees susceptible to disease-carrying insects. If you must prune because of broken branches, use a latex-based paint to cover wounds.

Never attempt pruning near any energized wires. Instead, contact your utility company to do the work.

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