Pruning Large Trees

Pruning Large Trees Tuesday, August 20, 2019

Author(s): Graham Herbst

Storm damage to large trees can cause large problems. These problems can exist immediately after the storm or become evident many months or even years later. Since large trees involve large branches with significant weight, this kind of storm repair is best left to qualified professional arborists. Here are some things you can do to help larger trees recover from storm damage.

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Inspect trees

Inspect trees carefully following a storm, particularly if a tree has suffered previous storm damage. Look for splits and cracks in the trunk or major limbs. Note any areas where water appears to be seeping from within the tree. Inspect the root collar, which is the area where the roots join the trunk. Look for uplifted soil or disturbed roots. If any of these conditions exist, have the tree inspected by a qualified arborist.

Pruning

Pruning large trees should be left to a professional arborist. Working in larger trees can be dangerous due to the heavy weight of branches. Larger trees also may be located near or under utility transmission lines. Working around utility lines is dangerous. Special training is required for arborists to prune trees when a utility line is involved. If you suspect a tree needs pruning, contact a qualified professional arborist. If utility lines are involved, contact your local utility company immediately.

After this has been accomplished, evaluate the tree for reconstructive pruning needs. The goal is to maintain as many live branches in the crown of the tree as possible so that sufficient leaf cover is maintained and the tree can return to normal vigor. At the same time, it’s important to remove severely damaged branches and minimize open wounds that will lead to decay. Severely damaged branches should be pruned back to a living parent branch using proper pruning cuts.

Mulching

Mulching is good for large and small trees. Spread mulch to a distance of at least 2-4 feet from the base of the tree. Wood or bark chips are the best mulch. Maintain a depth of 2-4 inches and do not pile up mulch against the tree trunk.

Don't fertilize

Fertilization is not recommended for damaged or stressed trees. Using fertilizer can upset a tree’s natural defense mechanisms and do more harm than good.

Removal

Determining whether a tree should be removed is a difficult decision for most home-owners. Major splits or cracks in the main trunk or in one or more major limbs may render the tree unsafe and require removal. In some cases, cable and brace work may be a viable option. Cabling and bracing should only be done by a qualified arborist. If done improperly, the tree will remain unsafe.

Consider tree function

If more than 50 percent of the tree’s living crown has been destroyed, removing it may be recommended. Be aware, however, that if the tree’s root system is intact, the crown will re-grow. Think carefully about the function the tree performs in the landscape. If this function (screening, shade, wind protection) is still being performed, you may want to try to salvage it.

Contact a professional

Although removing a tree is the last resort, there are circumstances when it’s necessary. An arborist can help decide whether a tree should be removed. If you decide to have a tree removed, professionally trained arborists have the skills and equipment to remove it safely and efficiently. In all cases involving larger trees, homeowners should consult a professional arborist.