While most people haven’t heard of the term pollarding, it’s a pruning technique that most of us will have seen at some point.
Whether you’re considering hiring an arborist to pollard a tree or you’re just curious to learn more, read on for all the must-know information about this technique. We’ve even included some handy FAQs to answer your remaining queries.
What Is Pollarding?
Pollarding is a popular tree pruning technique in which a tree’s crown is trimmed to limit its natural size. A tree or shrub is cut to its main stem or trunk, allowing its height to be controlled and the desired size to be maintained.
This technique dates back to Ancient Rome, as the Romans pollarded trees to create denser foliage. This tried and tested method is still used today, and you’ll recognise it in public spaces and gardens around the world.
Why Is Pollarding Used?
Pollarding is performed for many practical and aesthetic reasons. Here are just some of the reasons that it is used:
To improve the general health of trees
Pollarding can improve tree health in many ways. Firstly, it reduces the risk of pests, disease and fungus. Secondly, by maintaining the trees in a more juvenile stage, pollarding encourages them to live longer.
When the top of the tree is reduced in weight and windage, new branches and leaves grow more healthily.
To remove hazards to the environment and buildings
When left to grow very large, wood trees can become a hazard to the local environment. In cities like London, trees are pollarded to prevent them from interfering with electrical lines and street lights. Pollarding also slows root growth, so it can also prevent damage on the sub-level.
As a preventative safety measure
The larger a tree grows, the greater hazard it poses when branches become rotten or diseased. Therefore, Pollarding is often carried out to lessen the danger of rotten branches and leaves falling.
For aesthetic reasons
Local councils and landowners choose to pollard trees to improve their appearance, making the surroundings look neater with more uniform trees. If left to grow naturally, trees might overcrowd a park or garden.
One distinctive design you might recognise is lollipop trees- which are pollarded to have round foliage on top and a narrow trunk.
Trees Suitable For Pollarding
Pollarding cannot be used on all species of trees; it’s also best to start early and pollard young trees. Here are some of the trees suitable for this pruning method:
- Common lime
Because every tree is unique, it’s important to take a case-by-case approach to pollarding – not every elm, oak or tulip tree will be suitable. Consulting a tree surgeon is the best way to determine whether pollarding is the best option.
The Pollarding Process
When you hire a professional to pollard your tree, here is what you can expect.
Pollarding young trees
The best time to pollard young trees or shrubs is when they have just reached your desired size.
Pollarding is generally performed in early spring or late winter. It’s advised that you avoid tree pollarding in the autumn, as it makes trees susceptible to decay fungi entering the cuts made while pruning.
Choosing a framework
A framework refers to any branches that are left in place when a tree is pollarded. So the first thing a tree surgeon will do is select a framework.
On trees, three or five branches are generally left and cut back to a particular length. When twigs grow back, they will sprout from the ends of these branches.
On a shrub, an individual stem is typically cut to around a meter high. After pollarding, stems will grow from the top of this.
Pollarding is usually performed at least 6 feet above ground level to prevent grazing animals from eating the new leaves.
When a shrub or tree is pollarded, it’s important to maintain the cutting annually. However, in some cases, tree pruning will only be necessary once every few years.
To maintain a pollard, branches are pruned a short way above the previous cuts. In instances where leaf cover is needed, some are left in place.
Although the cost of having a tree pollarded every year will add up, it may be more expensive to deal with an overgrown pollard. To improve the health of an overgrown pollarded shrub or tree, there are a few things you can do:
- Take off weak or spindly lateral branches
- Consider thinning out or cutting back branches. You may be able to create a framework to effectively restore the pollard
- With some trees (like London plane), you can remove the outgrowth branches.
After major work is performed on a tree, its health needs to be monitored. This will help you to catch any issues before they become significant problems.
Pros And Cons Of Pollarding
As outlined above, this pruning technique is used for a variety of reasons. When performed correctly on suitable trees, you can expect several benefits:
- It helps trees stay healthy. By retaining a juvenile development stage, pollarding extends a tree’s lifespan. The promotion of new growth leads to healthier and stronger trees.
- It increases safety. Left unchecked, trees can do damage to the environment and the community. Pollarding saves them from interacting with power lines and buildings.
- It allows for more sustainable harvesting. Pollarding allows you to collect wood from your tree without cutting it down. By pollarding rather than felling, you’re minimising your environmental impact and maintaining a consistent supply of wood for years to come.
Provided that pruning is performed correctly by a professional, it will have only positive effects on a tree. However, when performed in bad practice, here are some of the cons of pollarding:
- It can welcome disease and fungi. If a tree is pollarded at the wrong time of year, the pruning cuts can make it susceptible to disease or fungi.
- There’s a risk of overgrowth. When pollarded oak, sweet chestnut, and beech trees are left to overgrow, their heavy branches can be prone to breakage. This will pose a safety hazard as well as damage to the tree.
When To Consider Using This Pruning Technique
Here are some cases in which you should consider getting trees pollarded:
- If street trees are overcrowding the space around them, or if any large trees pose a safety hazard.
- If a tree’s foliage is sparse and its branches weak.
- If a tree is casting too much shade.
- If you’d like to improve the appearance of your tree.