Topping is perhaps the most harmful tree pruning practice known. Yet, after many years of research, literature, and seminars, topping is still common. I cannot explain why topping is still done, but the reasons behind its harmful effects are evident.
What is topping trees?
Topping is defined as the cutting of tree branches to stubs or lateral branches that are not large enough to assume the terminal role. Basically, this refers to any cutting that will remove the top and/or sides of a tree or “shapes” the tree in any way. Common reasons behind topping are to reduce the size of a tree or to make it look a certain way. Home owners often feel that their trees have become too large and have become a hazard. However, topping is not a viable method for reducing size and, in fact, will make the tree more hazardous.
Topping puts severe stress on the tree and will put the tree into a survival mode. This survival mode causes the tree to grow multiple shoots from the site of the cut. At first, this may look like it is helping the tree by having so many new branches. However, these branches are a response to the loss of a previous branch and may cause the tree to drain its resources possibly die. Furthermore, the small branches that arise do not have strong attachments and will be prone to breakage when they grow larger, more so than the branch that was removed. Topping can also lead to decay, sunscald, and other fungal or bacterial diseases which will reduce the strength and longevity of the tree.
Most of all, topping is expensive. The cost of topping is not limited to the first time. If the tree survives, it will have to be pruned again the next year and years afterwards to maintain the bushy appearance. If it does not survive, it will have to be removed. This will all cost extra money and time; more than just paying the perpetrator. Furthermore, property values will be reduced. Healthy, well-maintained trees can increase property values by 10-20 percent. Disfigured, topped trees can be considered an impending cost. Further hidden costs can be a potential liability of topped trees. Topping is considered an unacceptable pruning practice; any property damage that is caused by branch failure of a topped tree can lead to findings of negligence in a court of law.
What alternatives are there to topping trees?
While most people would think that removing the top of an evergreen is unsightly and harmful, there are several other actions that can be done to conifers that have the same effect. Shaping, crown raising, and of course removing the top of an evergreen will reduce the heath, vigor, growth, and defence of the tree. Unlike the deciduous tree, the conifer may not sprout multiple new shoots out of the top. Generally, a lateral branch will turn upward and assume the terminal role (become the new top).
Evergreen trees, especially spruce and pine, cannot be shaped or sheered like a shrub. Even the shrub-like pines will be severely damaged if trimmed back or shaped improperly. When the ends of an evergreen are sheered off, the buds that create the next year’s growth are removed, and the branch cannot grow outward. Removing the buds does not hurt the tree, but the sheering between the buds will do the damage. Conifers cannot close the wounds made by sheering, and the chance for disease and decay is greatly increased. Furthermore, the thick look that is created after years of sheering will also increase the chance of needle fungi and insect infestations because of reduced air flow.
Finally, when it comes to the lower branches of spruce trees, they are only to be removed when completely dead. When the lower branches of spruce trees are removed, the tree’s production of food is greatly reduced because those branches have the most leaves and thus, food production abilities. Spruce and Pine trees will slowly stop using the lower branches as they get older and can replace the food produced by them in the upper branches. When this happens, those branches can be removed with no harm done to the trees. Until that time, removal of lower branches will only harm the tree. In addition, when a lower branch is removed, the branch above it will only sag down further, prompting the removal of that branch and so on. This chain reaction will put the tree in a downward spiral.
These acts are potentially expensive as they will need to be done each year to hold the desired look. When it comes to pruning your evergreens, the best action is no action at all.