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Pruning Young Trees

What and how to prune during the first 5 years after the tree has been planted
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At time of planting

Try to prune only dead or broken branches. It is best to leave as much leaf surface as possible to produce food that will work to build a larger root system. The roots and above ground parts will be larger after one year if only minor pruning is done at the time of planting.

A. Prune broken branches.

B. If more than one leader is present, remove the one with a crook or other defect to protect the main leader from competition.

C. Unless immediate visual clearance is needed, do not remove the small branches growing low on the trunk. These branches help the tree develop a strong taper and will eventually be removed.

3 - 4 years after planting

By this time, the tree’s root system should be anchoring the tree and providing nourishment to the growing branches. Growth is far enough along to reveal potential problems that can easily be corrected with pruning. This is also a good time to reduce wind resistance and excessive weight. Do not remove more than 25% of the tree’s canopy during thinning.

A. Remove branches that are heading back into the tree.

B. Remove branches that are rubbing.

C. Eliminate branches with narrow angles.

D. Remove suckers from around the base of the tree whenever they emerge.

5 - 7 years after planting

Your tree is quickly becoming an adult. Now is the time to ensure it has good structure over its lifetime. Try to imagine what your tree will look like as it grows larger. It is important to realize that branches do not move upward as a tree grows taller! The center of a branch that attaches to the trunk five feet above ground will always be at five feet.

  • Remove low limbs. If a limb will interfere with traffic, stop signs, or pedestrians, removing it now is a good idea. City regulations require the following clearances:
    • 7.5’ over sidewalks
    • 11’ over residential streets
    • 14’ over arterial streets
  • Thin tree canopy as discussed above. Remove those branches that are rubbing, growing back toward the tree, or attached at narrow angles.
  • Thin to create more even spacing between lateral branches as needed. If possible, evenly space lateral branches 8-12 inches apart to produce an ideal “ladder” at maturity.
  • Don’t over-prune. Removing too many branches at once reduces the tree’s ability to produce food. Never remove more than ¼ of the tree’s canopy at one time. If more work is needed, phase the work over multiple years.\