Pollarding and Repollarding
This common process involves keeping trees at a smaller height than they would grow if left alone to naturally grow.
Pollarding is a process that keeps trees at a smaller height than they would grow if left alone. Typically a juvenile tree is allowed to grow to a designated height, for example two or three metres, and then the first pollard is carried out.
During the first pollard the lateral branches and the main leader are all cut off at the designated height effectively reducing the tree to a small trunk with a few bare branches. The process is then repeated every few years to remove all the regrowth from the initial pollard point. The tree develops a knuckle where all the regrowth shoots are being cut off and this point is maintained as the pruning point for each repollard. This technique is most commonly found in street trees in built up areas to prevent the trees from growing too large and invading phone wires, growing laterally over roads.
It is important to understand the difference between pollarding and topping. Pollarding must be started early on in a trees life and then maintained. It is not possible to pollard a mature tree if it has never been pollarded before. And with each repollard the branches are cut back to just above the previous pollarding points. Topping typically involves cutting off the top part of the tree right across the main trunk. Topping is not considered correct practice.