How To Repair A Gash In A Tree

An oak tree standing in a forest with a wound where bark is missing. — **This cherrybark oak was damaged by equipment. Wounding forth roots allows entry of damaging fungi, resulting in decay and futurity butt rot.**

Copse in urban and landscaping settings are more probable to receive wounds compared to trees in natural stands. These wounds can be caused by accidental contact with automobiles, construction equipment, or backyard equipment that damages the trunk or surface roots. Tree wounds can too occur through intentional treatments like pruning, as well equally natural processes such as storms, fires, and brute damage.

When a wound penetrates the bark and damages the cambium (a thin layer of vascular tissue responsible for water and nutrient move within a tree), information technology also exposes the interior of the tree to damaging organisms such as fungi and bacteria. Once the tree has been wounded, these organisms can enter heartwood and begin the process of decay. Decay results in discolored wood and structurally weakened and/or unattractive stems with shortened lives. For this reason, recommendations are often made to apply some sort of wound roofing to help the tree recover. All the same, decay cannot be reversed, and these measures are typically futile and negatively inhibit a tree's natural sealing processes.

A tree responds to wounds past compartmentalizing and forming suberized (cells accept on a sealing function), lignified (strengthened) woods known as callus tissue that prevents entry of pathogens. Callus tissue develops at the edge of wounds and grows toward the center. This new wood remains for the life of the tree, overlying the wound, and information technology limits farther spread of disuse. The positive benefits of compartmentalization exercise not stop with endmost off damaged tissue. While the process is not well understood, trees besides create chemical boundaries around infected cells that continue to react to pathogens, thereby further circumscribed damage. After these processes have occurred, decay will not spread unless something breaks the barrier.

A tree trunk that has been sawed into a section shows signs of interior discoloration. — This is a cantankerous section cut from large white oak that underwent pruning treatment. While callus tissue grew over the severed limb, discoloration and decay occurred. Tree wound dressing was applied only flaked off after 2 or 3 years, only serving as a bulwark to callus tissue connection with cutting surface.

A sweetgum tree in a forest shows signs of an old injury, but new woody tissue is growing around the edges of the wound. — **Callus tissue forms along wound edges on a sweetgum trunk.**

Should Tree Wounds Be Repaired?

Broken Limbs, Splits, and Physical Repairs

Weather events, impacts from lawn/construction equipment, and chafe from falling copse often result in physical damage to tree limbs and boles. In these cases, cleaved limbs can be cutting in a manner that avoids bark stripping. It may be possible to repair smaller dissever branches or trunks with a multifariousness of techniques used by arborists. Wounds with ragged torn bark should take loose bark removed and the rough edges smoothed by cut with a saw, pocketknife, or chisel. For more information on physical repair methods, please consult Mississippi Country Academy Extension Information Sheet 1355, Repairing Storm-Damaged Shade, Ornamental, and Fruit Copse.

Wound Dressings

Historically, many people recommended treatment of tree wounds. Usually, the recommendation involved applying tree paint. We now know that covering wounds with paint is detrimental, but some go on to recommend the practice, and tree wound products are still marketed. Many of these products are petroleum-based—tar, cobblestone, paint—and serve only to impede callus tissue germination and successful compartmentalization. These products too seal in moisture, which prevents drying and encourages decay. In addition, some of these products can really be used as a source of food for fungi. In most cases, tree wounds can seal themselves and should be allowed to go through the natural processes described earlier.

A tree with a limb cut off has a black material coated over where the limb used to be attached to the trunk. — **Tree wound dressing was applied to this severed limb.**

Filling Cavities

Equally with applying wound dressings, filling cavities in copse was an accustomed do at 1 time. For cosmetic purposes, cavities would exist cleaned and scraped downwardly to undamaged wood and filled with cement, mortar, bricks, or similar materials. These processes typically broke the tree's physical and chemical compartmentalizing barriers and allowed disuse to continue unimpeded. The ceremoniousness of filling cavities depends on several factors.

In cases of pocket-sized cavities, it is commonly best to allow the tree's natural defensive processes to seal the crenel. Larger cavities may never seal over; however, they may not be a trouble if the tree is able to successfully compartmentalize the wound and further impairment does not occur. Some research has shown that filling large cavities can provide a surface for callus tissue to attach and forbid in-roll as it grows inward. However, filling cavities is typically plush, does non cease decay, and often results in rupture or abrasion of the boundary that separates decay and audio forest. Therefore, it is cavity cleaning—non necessarily filling—that often results in further damage to the tree. If it is necessary to fill a cavity, callus tissue that has formed must not be damaged.

Closeup of a tree trunk with a hole that has been filled with cement. — **A cavity in a pecan has been filled with cement. Cavity filling does not foreclose further decay simply is sometimes performed for aesthetic purposes.**

Pruning Wounds

It is very common to encounter trees with structural damage that resulted from improper pruning in urban areas. Proper techniques should be used to remove expressionless, dying, broken, low, chancy, or otherwise undesirable branches. Pruning places some stress on trees by reducing photosynthetic capacity when food-producing leaves are removed (if limbs are living). It as well creates wounds that require the tree'due south resources to seal and guard confronting entry by disease and insects.

Pruning cuts should exist performed in a manner that maximizes chances of a tree's natural sealing abilities. Cuts should be smooth and clean; they should not leave stubs and should maintain the co-operative collar. A branch collar is the swollen expanse where the co-operative attaches to the trunk. Cutting above the branch collar results in a smaller area that callus tissue must comprehend. Boosted information on pruning technique can be found in Mississippi State University Extension Data Sheet 204, Pruning Landscape Plants.

Suggested Reading

Bachman, G. R. 2022. Repairing storm-damaged shade, ornamental, and fruit trees. MSUE Data Sheet 1355. 4p.

Clatterbuck, W. K. 2006. Tree wounds: response of trees and what you tin practise. UT Extension Publication SP683. 4p.

Denny, Chiliad. 2022. Pruning landscape plants. MSUE Information Sheet 204. 4p.

Shigo, A. L. 1982. Tree health. Journal of Arboriculture 8(12): 311-316.

Shigo, A. L., and W. C. Shortie. 1983. Wound dressings: results of studies over 13 years. Journal of Arboriculture 9(12): 317-329.

Publication 3533 (POD-nine-20)

By Brady Self, PhD, Associate Extension Professor, Section of Forestry.

Copyright 2022 by Mississippi State University. All rights reserved. This publication may be copied and distributed without amending for nonprofit educational purposes provided that credit is given to the Mississippi State University Extension Service.

Produced by Agronomical Communications.

Mississippi State University is an equal opportunity institution. Discrimination in university employment, programs, or activities based on race, colour, ethnicity, sexual activity, pregnancy, organized religion, national origin, disability, historic period, sexual orientation, genetic information, condition equally a U.S. veteran, or any other status protected by applicative police is prohibited. Questions almost equal opportunity programs or compliance should exist directed to the Office of Compliance and Integrity, 56 Morgan Avenue, P.O. 6044, Mississippi Land, MS 39762, (662) 325-5839.

Extension Service of Mississippi State University, cooperating with U.Southward. Department of Agriculture. Published in furtherance of Acts of Congress, May eight and June 30, 1914. GARY B. JACKSON, Director