Filling of hollow trees, a process called “cavity filling,” was practiced by arborists for many years. Today we know that the materials normally used to fill a tree cavity are very abrasive. Natural tree movements, such as swaying and twisting, rub the inside surface of the tree cavity against the filling, further weakening the tree’s defensive walls and allowing decay to expand. In addition, we know that these materials do not allow the tree to bend and therefore renders the tree more susceptible to storm damage. Also, because of these tree movements the cavity-filling materials do not bond with wood. Gaps are often the result and these gaps frequently trap water. This dark and moist environment allows decay fungi to proliferate.

Bob Rouse, Staff Arborist at the National Arborist Association, confirmed this when he said, “The cement holds moisture, creating a favorable environment in the filled cavity for the decay organisms!”

How should trees with cavities be treated? Recent research shows that it is better to leave the cavity open – remember no type of drainage, sterilization, fill material, wound paint, or scraping treatment stops decay – and simply take the necessary measures required to improve the overall health of the tree. A healthy tree has the strength to compartmentalize and wall-off decay.

In addition, this practice just causes havoc on the equipment when the tree and stump have to be removed. Chain saws and stump grinders cannot cut concrete and bricks.

In summary tree experts recommend:

• Not filling cavities with cement, brick or any type of filler;
• Supporting, if required, with cables or braces

We at lookin’ good treeman services are concerned with this practice and present the information above for the benefit of your trees.

A tree cavity is similar to a tooth cavity. Without proper treatment, the situation can only get worse. Unfortunately, cutting down on sweets and brushing more frequently will not help to prevent a tree cavity. In simple terms, a tree cavity is a neglected bark injury that can be the result of many factors. The most common are improper pruning, mechanical injury and storm damage.