crowd reductions (inc pollarding & monolithing)

What is a crown reduction? At a basic level this is simply making the canopy of the tree (the crown) smaller. This can vary hugely from a small percentage reduction (like 10% on a big veteran tree) to a complete canopy removal in the case of monolithing.

Much of our work involves making the canopies of trees smaller in order to allow more light into properties and gardens. Although harder work for a tree surgeon to carry out, most trees, even large mature trees, respond well to a crown reduction provided it is carried out at an appropriate time of year for the particular tree and is done so to a degree that the tree can cope with.

Most trees can cope with crown reductions of up to 30%. Younger and more vigorous species can cope with more. Some trees will even grow back having had all their canopy removed provided they are young enough and if implemented at the right time of year. 

We will often quote in terms of percentage crown reductions. If a deciduous tree with a canopy of 20m height and spread is to be reduced by 10% then that would equate to a reduction of 2m across the width and height of the tree assuming the crown is approximately round. Reductions are generally carried out all round the canopy of the tree. So effectively the arborist would remove approximately 1m off the ends of all the branches equating to an overall reduction of 2m. Below is an illustration of a typical crown reduction

Pollarding is a type of reduction whereby a tree is reduced to the same growth points on a regular basis.

Many trees can be pollarded, but willows are a good example of a tree which responds very well. The images below show a willow before and after we carried out the pollard. Pollarding is an excellent long term management approach to keeping the size of trees in check.

A monolithed tree is one where the entire canopy is removed but the trunk is left standing. Generally, this is carried out where the tree is terminally compromised but the trunk is left standing as a habitat for birds bats woodpeckers etc.