"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 as 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—it's especially helpful if branches are encroaching on a power line.
- 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. The list, which is very short, includes redbuds and other small deciduous trees. Large deciduous trees and conifers, like white pines, do not lend themselves well to pollarding. The only species that might benefit from pollarding are small ornamental fruit trees that will not pose significant treats to people or property regardless of their structural condition.
For trees that do need pollarding, the best time to pollard them is usually late winter or early spring.
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. After the initial trimming, repeat the process every couple of years to maintain the shape.
No large deciduous species should be pollarded or topped. Some species, such as willows and mulberries, can resprout regardless of what you do to them. They are sometimes cut down and allowed to resprout, which is technically topping, but this is only done as an alternative to full removal and should never be a first choice solution.
Topping vs. Pollarding
Pollarding and topping are sometimes used interchangeably, but they are not the same. The major difference between the two words: Whereas pollarding is done with design in mind, topping is done out of expediency. More thought and planning goes into pollarding, which is considered an art form, much like 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. Topping is not good for trees and should not be done if you care about a tree at all. Topping a tree can kill it, though not all trees that have been topped die a quick death. Some live on for many years.
Once you've had a tree topped, you are stuck with the result. Pollarding is an ongoing operation done to maintain a shape; topping is usually done just once.
A third arboricultural term you will hear that's related to pollarding and topping is "canopy reduction." With canopy reduction, the length of a branch or a number of branches is reduced. It should be your first choice for an intervention before you consider topping, since it is the best practice for trimming a tree that has outgrown its space. An example of a situation that may call for canopy reduction is when one or more branches on a tree threatening to fall down on utility wires or hang out over a road, posing a safety hazard for automobile drivers.