A basic tenet of modern arboriculture is that you cannot prune a big tree into a small healthy one. Total foliage loss in a mature tree should be less than 20% and where possible significantly less than 20% – pruning is generally an exercise in containment.
There are many other aspects to consider – for example limbs act as dampeners, reducing the impact on the tree from strong winds, and removing whole limbs will put stresses on a tree’s structure that it has never encountered.
Before and after images – Manchurian Pear (pyrus ussuriensis) canopy reduction in Torquay.
Should a sustainable pruning regime be unlikely to achieve containment goals, some thought should be given to removing and replacing the tree with a more suitable species.
Some commonly planted species, generally exotics like London planes, ash, and robinia, can lend themselves to pollarding, a pruning regime where all limbs are taken back to a predetermined length. The tree will respond by sending out a crop of new shoots, and in time will develop a small, usually quite dense, canopy. To be successful, pruning should take place every year, or every other year, and will result in the development of callous at the wound sites, and over time, eventual closing off or occluding of the original pruning wounds.
Whether reducing weight and deadwood in large eucalypts or pruning an exotic feature tree, we have the skills and experience to leave a tree looking its best, to retain a natural branch structure, to best facilitate eventual wound closure, and to minimise the threat of fungal and insect pests over the long term.
You will not hear us say:
don’t worry, it’ll come back!
Regrowth from lopping. Extremely poor practice.
Callous growth on a Barwon Heads Eucalyptus 2 years after limb removal
Weeping Apricot thinning & dead-wooding in Belmont