Crown Reduction…..What is it?

So you’ve read the pages on this site regarding crown pruning, but you want a little more information as to why we do a crown reduction, and what is the correct way?

Your garden may be home to a large mature Beech tree, and you may now be thinking “Maybe we should get it cut”. You then search google for tree surgeons in your area, only to find an abundance of businesses. You have an image in mind of how you want your tree to look and maybe what size you want the tree to be. You then explain to the tree surgeon exactly what you want doing. If the business is a reputable one, they will then explain the correct way of doing the works adhering to the British Standard that relate to tree work practices.

So what is the correct way of carrying out a crown reduction you ask? The answer is long, specific and dependant on the tree itself and surroundings, but generally speaking a crown reduction shouldn’t exceed 30% of the overall foliage. Once we know the percentage of the crown to prune we can then work out the approximate length of branches to be removed, although it may not sound as severe as you was hoping but there are reasons we stick to these guidelines.

Why not “Chop it in half”?

Tree trimming

The result of topping!

For the majority of tree species in britain it is bad practice to severly cut them back, this practice is known as “topping”.

To prune a tree to this extent can be detrimental to it’s health whilst making it unattractive, the beautiful Beech tree has stood for hundreds of years in your garden and is now half a tree and can potentially be dangerous. So let me explain…..

A tree needs foliage for photosynthesis. It also has enough foliage so sustain itself and some more for it’s reserves over the winter months. This foliage is vital for the workings of the tree, therefore removing a large percentage of it’s foliage would greatly upset this balance, and the tree will then react accordingly. The first thing the tree will want to do is put back the foliage surface area that it has lost, it does this by sending out vigorous growth to compensate. This growth is called epicormic growth or sucker growth. Epicormic growth is fast and very straight, resulting in the natural growth being removed and replaced with un-natural upright branches. In addition to the unattractive structure it creates, the regrowth is weaker and more prone to snapping! Unlike natural branches and limbs that have grown at the natural rate and bound strongly into the parent limb, epicormic growth is attached very shallow to the parent branch making this growth weaker.

So what is the correct way to prune my tree?

Crown pruning

Crown reduction done correctly

So this is where the professionals come in! We have worked out the correct percentage of foliage that should be removed from the crown by placeing all the cuts in the correct positions.

When an arborist makes a pruning cut it is important to adhere to the guidelines set by British Standards, the guidelines state that the diameter of the cut should not exceed 30% the diameter of the branch to which you’re pruning to.

A good arborist should be climbing to near the very tips of the branches to select an appropriate cut position, whilst selecting these, the climber should also be aware of the resulting tree crown shape.

Although the purpose of a crown reduction is to make the tree smaller, it is also good practice to make the tree a pleasing shape. It is important to create a balanced and well-structured crown. A balanced crown reduces the effects of wind damage to the trees limbs lessening the likelihood of snap-outs.


There are exceptions!

So we’ve covered the right and the wrong ways to prune your tree, there are certain species of tree that sometimes can’t be pruned in the way described. Conifer trees are an exception to the rule as there is no way of reducing the width of the them, we can however reduce the height. The height can be reduced quite severely with little or no effect on the tree. The majority of conifers don’t re-grow from cuts.

Lombardy Poplars are also often reduced but can only really be reduced in height. Strictly speaking it’s classed as “topping”

There may be situations where a tree needs to be pruned severely to reduce weight on a damaged limb, or if the limb is over-extended.

We sometimes come across trees that has a severe lean in one direction. In this instance the best option may be to reduce the height of the tree or a reduction of one side to alleviate the weight.

What to look for in a tree surgeon.

A professional tree surgery business requires public liability insurance, just incase the unthinkable happens, make sure they are adequately insured. Upon quotation the arborist should be able to identify the tree to give the correct advice.

If you require a professional tree surgery business to undertake a crown reduction and you’re in Leicester give us a call and we will gladly help!