Pruning Pohutukawa Trees Auckland Blog post by Rossy. One of our recent jobs at Pro Climb – Tree Care Auckland was to carry out some pruning works on a mature Pohutukawa tree growing in a residential suburb in Auckland. Due to its growing location, with targets beneath the tree, it was decided to prune the dead branches from the canopy to remove any hazard that they may have posed. The client also expressed concerns that the tree was outgrowing its surrounds, and if possible, could we take measures to retain it at its current size. The nature of the tree and its past management both contributed to difficulties when it came to carrying out the pruning. These challenges will be discussed in the Blog post below.
There are a number of factors that determine the form and shape of a tree.
Environmental factors play a large role in influencing how a tree will grow. Branches will grow towards the light, and away from gravity and prevailing winds. Nutrients in the soil and available water will also strongly affect tree growth. The species of tree its self will also dictate its form. Some trees, such as Pohutakawa, have very dense foliage cover. Most of their leaves are concentrated to the outside of the canopy in order to intercept the light from the sun for photosynthesis. This makes the inside of the canopy much more shaded than other tree species, and as a result, Pohutakawa tend not to have as many small branches and leaves further in towards the trunk.
A factor that we have not yet covered that influences the form of trees is work by Arborists. By pruning branches and leaving others, Arborists can dictate how a tree grows and the form it takes. This process may be fully conscious; with the Arborist using industry best practise techniques and having a long term view of the tree in mind. Or, it may not involve much thought; branches being removed for short term effect and financial gain. Arborists can be working with a tree and encouraging its natural processes or they can be working against them.
Pruning Pohutukawa Trees Auckland by Expert Arborists
Back to our Pohutukawa. Previously, in an attempt to create light to the property, an Arborist had “thinned” the Pohutukawa. Thinning is an Arboricultural practice that is often misinterpreted. A full definition of thinning can be found at the link at the bottom of this blog. The practise of thinning is more about the branches you leave behind than the ones you remove. It is the remaining branches that form the new canopy so it is vital that you leave a structure that will support healthy tree growth. In the case of our Pohutukawa, the previous Arborist had removed all of the internal growth of the tree and had left all of the branches on the edge of the crown untouched. This practise (which is almost opposite to the definition of thinning) is known as “lions tailing” and often leads to future branch failure.
Pruning Pohutukawa Trees Auckland and Tree Care Advice
The combination of having a tree that naturally has the majority of its foliage concentrated to the edge of its canopy and an Arborist that removes all of the internal growth is recipe for disaster. The dense foliage on the outside of the canopy still remains and so this is where the tree grows from. The weight and sail area of the branches is focused towards their ends and increases the chance of their failure. This form also makes the tree problematic to prune in the future. Managing the tree at its current size is very difficult as there is no internal growth to prune back to, and the Arborist is very limited in what they can achieve.
For Pruning Pohutukawa Trees Auckland Contact an Arborist
This highlights the importance of knowing who is working on your trees and what knowledge and experience they have. Make sure that anyone working on your trees has a long-term management plan in mind and is not just out to make a quick buck. A bad pruning job may only take a few hours but its effects may last for years to come.
The New Zealand Arboriculture associations guide to pruning can be found at the following link: