"Pollarding trees" means cutting them back nearly to the trunk, so as to produce a dense mass of branches. It is sometimes done today for aesthetic purposes: The resulting "lollipop trees" can be appealing to those who crave horticultural oddities. But pollarded trees aren't for everyone, since they can be stark-looking when they do not have leaves.
There are also practical reasons for pollarding trees, including:
- To keep a beloved tree from outgrowing its bounds on a private landscape (which would necessitate its removal)
- To keep trees on city streets or in parks more compact
- Traditionally, the cut branches were either fed to livestock (fodder), burned as fuel, or used to make things. Pollarding was thus a way of using wood from the tree over the course of many years, rather than cutting it down and having merely one-time access to its wood.
Suitable Trees, Maintenance
Pollarding begins on young trees, and the process is repeated every year or two throughout the life of the tree (meaning that, if you decide that this is something that you would like to subject your trees to, be prepared to undertake significant landscape maintenance). Only certain types of trees are suited to pollarding, including:
- Ash (Fraxinus)
- Elm (Ulmus)
- Horsechestnut (Aesculus)
- Maple (Acer)
- Oak (Quercus)
- Redbud (Cercis)
- Tulip tree (Liriodendron)
For most trees, the best time to pollard them is late winter or early spring. The exception is maple: Avoid pollarding a maple in early spring because that is when its sap is running. To pollard a tree, select three or five branches that you want to leave in place to form a framework, removing the rest entirely.
Cut the framework branches back to the length you want and wait for new growth to sprout from them.
Topping Versus Pollarding: Superficially Similar, but Different Operations
Now that you know the definition of "pollarding," you can distinguish it from "topping," which is another term used in arboriculture. But here is the difference between the two words: Whereas the former is done with design in mind, the latter is done out of expediency. More thought goes into pollarding, which is considered an art form, as is topiary.
Topping means cutting older trees down almost to the top of the trunk. Topping trees is sometimes used as a less expensive alternative to their full removal, which can be quite costly in the case of large old trees. It is done not with an eye to what is best for the tree, but because the homeowner is in a pinch. When hiring arborists or hiring tree services to trim tree limbs that hang threateningly over your home, make sure they have no intentions of topping your tree if the tree has any importance to you. Topping, in such circumstances, is a highly disreputable procedure.
Some types of trees may die after topping, but this fact often holds little importance to the homeowner, who may actually be glad to have the tree die if it is unwanted.
Do note, however, that not all trees that have been topped die a quick death. Some live on for many years.
But with their appearance ruined through topping, the homeowner might actually be better off if the unwanted tree did die. Any gracefulness in form that the tree had had prior to the procedure will be lost forever. Once you have had a tree topped, you are stuck with what it looks like: While pollarding is an ongoing operation, topping is usually done just once.
While "pollarding" and "topping" may appear to beginners to be similar terms, the former boasts a superior pedigree. Pollarding goes back centuries. We know it was being done in ancient Rome because Propertius, the Roman poet, mentions it.
A third arboricultural term you will hear that is related to pollarding and topping is "canopy reduction." With canopy reduction, the length of a branch or a number of branches is reduced.
Because it is done for practical purposes, canopy reduction is more similar to topping than it is to pollarding. An example of a situation that may call for canopy reduction is when one or more branches on a tree threaten to fall down on utility wires or hang out over a road, posing a safety hazard for automobile drivers.