Tree topping is the practice of removing large branches and/or trunks from the top of a tree's canopy. Topping is often harmful for the tree. Large pruning wounds often fail to heal and become entry points for disease and pests, undermining the long term health of the tree. Aesthetic appeal is compromised as the natural shape of the tree is lost. Trunks grow at the topping location and as these weakly attached trunks increase in size, they often fall during windstorms.
Previously topped trees are often dangerous and should be inspected by a qualified arborist who can recommend possible solutions: removal, cabling/bracing, or ongoing inspection. Better alternatives to tree topping, based on scientific research, are replacing the practice of tree topping. Spiral thinning (canopy thinning) decreases wind resistance and allows the wind to pass through the trees, decreasing the likelihood that the tree will fall due to wind-throw. It also allows more light penetration and air circulation, both important for the tree’s health.