A hat-racked shrub is left as a bare trunk with a few thick stumps sticking out, no leaves and no twigs. It is the most severe pruning there is, and it only pays off on dense, bushy shrubs such as holly, yaupon and boxwood; on anything else it shocks or kills the tree.
Hat racking (or hatracking) is the most severe type of pruning. It is only suited to a very small number of tree species.
Hollies and boxwood are two tree types that can cope with undergoing hatrack pruning.
However, this technique should be avoided when proper pruning is possible since it’s very stressful for the shrub.
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Hat racking a tree literally means “turning the tree into a hat-rack“. So in the end, a shrub will look like a trunk with a few large stumps sticking out from it, without any leaves or twigs anymore. Ready for any giant to hang its coat on!
1. Whenever multiple trunks have formed, cut down all but one (the most vigorous one). Multi-trunk growth is common in yaupon, lilac and holly.
2. Determine the height you’re targeting for the tree. Perhaps you’ll cut it down by half or by a third.
3. Determine how wide the largest lower branches of the tree should be. Usually you’ll cut them back to only several feet, or about a third of their original length.
4. With the lower branches cut, and the tip removed, visualize a pyramid or a cone. The cut tip of the tree is the tip of the shape, and the shortened large lower branches are the base.
5. Cut all remaining branches so that they fit within this cone or pyramid.
6. Eventually, cut some branches all the way back to the main trunk if you want to lighten up the tree even more.
You’ll be left with only a skeleton that seems hacked bare. It’s surprising, but from these branches new twigs will sprout and bear leaves.
Hat racking suits only a short list of dense, bushy shrubs; everything else is shocked or killed outright. This table gathers the groups named in this article, so you can check your own tree before the saw comes out.
| Tree group | Examples | Response to hat racking | Follow-up needed |
|---|---|---|---|
| Hollies and yaupon | Holly, yaupon, dwarf yaupon | Bounces back well; the classic candidate | Cut all but the most vigorous trunk where several have formed |
| Flower vines | Jasmine, ligustrum, myrtle | Survives, but many small twigs crowd the cuts | Yearly pruning for two or three years to reselect a leader |
| Fruit trees | Olive, grape vine, chestnut | Recovers, but no flowers or berries the first year | Grape vines need annual follow-up pruning |
| Ornamental evergreens | Juniper, boxwood, podocarpus, yew | Bounces back from the bare skeleton | Keep the shrub below head height, as regrowth is weak |
| Pollarded trees | Plane, birch, ash, willow, beech, hornbeam, lime, oak | Only acceptable if already maintained as pollards | Cut back to the original cut every few years |
| Palms | Any palm | Never: it grows from a single terminal bud and dies | None; reduce the crown of nearby trees instead |
For anything not on this list, crown reduction is the safer way to shrink a tree.
Hat racking should only be performed on dense, bushy shrubs that have grown too tall. Typical shrubs are holly, yaupon and boxwood.
The following species of trees can be hat racked and will bounce back:
Any other type of tree or species should not be hat racked! In many cases it will shock and kill the tree, and if it survives it will need years to recover.
You should not hat rack oak, birch, beech, ash, and many more, unless you diligently maintain them as pollard trees.
Also, you should never hat rack a tree if you intend for it to grow taller than a person. Weaker regrowth means that any person walking beneath it is at risk of having a branch break while under the tree!
Many tropical tree species are very vigorous and will survive hat-racking. However, it’s preferable to resort to crown reduction. Crown reduction is the best way to “shrink a tree”!
Never hat rack a palm: it grows from a single terminal bud and will simply die.
Suddenly exposed trunks and thick stumps can scald under strong tropical sun, so leave a few shaded lower branches or paint the bare bark with diluted whitewash.
Hat-racking is generally not suited to very large trees. For shrubs and bushes, disadvantages are minimal, but serious issues arise for large ones.
Indeed, branches that grow back from the remaining stumps are much weaker. Since they take off at an angle from the cut on the bark, fibers in the wood are neither aligned nor continuous.
As the tree grows, this is covered up with bark and thickens, but if loaded with snow, a swingset, or simply strong wind, the branch may snap.
This is true for flower vines and grape vines. A consequence of cutting a branch sharply is that no “leader” branch naturally channels growth anymore. Instead, many small twigs pop up around the cut and crowd each other out.
To bring the tree back to a single branch again, a pruning follow-up is needed every year for two or three years. Each time, a leading twig is selected and all others are removed.
Hat-racking is sometimes said to be cheaper than a proper pruning. This may be true because hat-racking doesn’t require any skill apart from knowing how to use the cutting tools.
Diseases like fungus enter the tree through wounds.
Open cuts also make the tree vulnerable to late frosts, if ever the hat racking was performed too soon.
In some places hat racking is illegal or restricted. There are several reasons for this. Trees that are hat-racked have weak joints when they grow back, as seen above. This makes the practice dangerous, especially in parks and such.
A second reason is that hat racking interferes with land value. Simply put, a hat tracked tree is considered ugly for a few years. This brings property prices down. Home Ownership Associations sometimes forbid hat racking for this reason. Remember to ask if it’s authorized where you live for large trees.
The best is simply to prune your tree regularly. It’s perfectly possible to keep a tree at the same size for decades by pruning it diligently.
If you do have to remove a large branch, always carefully consider where the cut should be. Ideally, cut just above a node or an existing split, so that the remaining (smaller) branch can absorb growth naturally. When you do this for all the large branches of a tree, it’s called crown reduction.
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Hat Racking is not a real term used by any real arborist. You are essentially pollarding the shrub or tree. Then you are advising people to prune their plant from that point instead of continuing the pollarding practice.
I am confused as to why you would make up, or use the wrong term, when in your article you mentioned the proper term pollarding many times. So weird.
Hi James, it’s not a common term mostly because it’s not a common practice, especially because arborists themselves wouldn’t be caught red-handed doing this. I agree with you! However, it is used to describe the fact of topping a tree and cuttings its branches in the manner described. This is often simply to state that it’s prohibited or not allowed in local regulations or in neighborhood guidelines.
It’s different from pollarding because when you pollard you intend to keep the same structural branches and regularly cut off growth from that point on afterwards. Hat-racking is typically a one-time action, that shouldn’t be repeated, and instead, the better technique of pruning to shape the tree is followed. The cuts that result from the hat-racking are gradually eliminated thanks to proper pruning.