Crown Thinning

Crown thinning is the process of removing select branches to thin out the fullness of the tree. It is an important part of maintaining a healthy tree and may be carried out for a number of reasons.

Light To let more light into the tree. When branches get too crowded, leaves and stems compete with one another for light and nutrients.

Weight To reduce the weight of branches, making it less likely they will break.

Wind resistance To reduce the branches of an overgrown tree. When strong winds cannot pass through it naturally, the whole tree acts like a sail and is at risk of being knocked over. Reducing the branches protects the tree by decreasing the wind resistance and lowering the safety risk.

Flowers and Fruits The production of flowers and fruits will be higher on a tree that has been thinned with more sunshine reaching its branches.

Shade To simply decrease the fullness of the tree and increase light to enable it to penetrate the ground and any other plants in its shadow.

Illustration courtesy of the European Aboricultural Council.

What does crown thinning involve?

Crown thinning is the most common type of pruning of mature trees and involves the removal of a portion of smaller or tertiary branches. This is usually at the outer crown of the tree to produce a uniform density of foliage around an evenly spaced branch structure. The pruning is usually between 10-20% of the tree without changing the overall dimensions. It does not alter the overall size or shape of the tree.

Crown thinning is usually confined to broad-leaved species such as holm oak trees, hornbeams, beeches and fruit trees. It is rarely a once-only operation, particularly on species that are known to produce large amounts of epicormic growth.

Over thinning by removing more branches, foliage and stems than your tree can safely handle, can severely impact a tree’s health. To maintain a healthy tree and to reduce the risk of causing stress to the tree, it is important to hire a qualified arborist to carry out this type of work.

A professional tree care specialist should be able to advise you the best method of pruning for the tree and recommend an alternative service if crown thinning is not appropriate.

How we can help

We make an initial assessment to work out how much thinning is required and if that will be a safe amount for your tree to cope with, without impacting its health.

We then select the right branches to prune from the edge of the canopy, selecting limbs and stems that are crossing, rubbing or damaged first. It is important to only remove the minimum amount and review annually if necessary. As bizarre as this may sound, a tree that has been correctly thinned should still look completely unpruned.

We have extensive experience of this and many other types of pruning of trees in different locations – from smaller garden trees to larger trees in parks or public spaces, providing we have the relevant permission to do so. We will always make an assessment of the tree taking into account the situation and surroundings, identifying any risks and hazards.

With access to all the necessary specialist equipment, we work in accordance with the latest health and safety guidelines and operate in a safe, efficient and considerate manner.

We are tidy chaps and will always leave the area clear removing the chippings, twigs and fallen leaves, although wood can be left if requested.

Of course, a tree will always revert back to its original size so we recommend that you call us rather than carrying out any work yourself. We will be able to keep a trained eye on the process to ensure your tree is in optimal health.