When a tree grows taller than expected, casting unwanted shade or colliding with buildings or other structures, it may seem obvious to just cut off the top. However, this is not a good idea! Topping a tree will stress it and weaken it, making it less safe and leading to costly, long-term maintenance headaches. It also ruins the tree’s natural shape and beauty.
A tree is said to be « topped » when the main stem or largest branches are cut off, removing much of its canopy of leaves and retaining only smaller, less vigorous lower branches. Topping can remove half or more of a tree’s leaves. Since leaves are a tree’s food factories, losing so many can starve the tree. Desperate to replace its leaves, a tree will respond to topping with a flurry of feeble new growth. But beware, those new branches will be weak and likely to fall in storms!
The many large, open wounds that topping creates on a tree’s main stem and branches also invite diseases, insect infestations and decay. The remaining branches may rot and become unstable. Eventually, the tree may die.
Topping can create expensive problems. If the tree dies, it will have to be removed. If it survives, it likely will need corrective pruning, although it will never recover its original, natural form.
Since topping is not an approved professional practice and causes safety risks, homeowners may be liable for damage from the failure of a topped tree, not to mention that a tree disfigured by topping also is an eyesore that can reduce the value of your property.
A trained, certified arborist may be able to prune a tree to reduce its overall size somewhat. However, that kind of pruning won’t work for all species or in all circumstances. It’s better to avoid topping by carefully choosing a kind of tree that will never outgrow the available space. Each species of tree has a natural size and shape. It is unhealthy for a tree to carve it up to try to make it smaller or differently shaped than it is genetically programmed to be. That’s one reason it’s so important to choose the right tree in the first place.
<em>Thanks to the Morton Arboretum for the article</em>