Pollarding is useful with trees that have numerous branches arising from the same height on the trunk. Pollarding is carried out initially when a tree is young but after it has become established and has a stem diameter of between 1″ and 2″ at the desired height.
Pollarding is a method of maintaining trees at a certain height and allowing a more formal appearance. Pollarding has been used historically to mark boundaries as well as a method of feeding cattle. Fresh growth was able to be grown out of reach of the animals and then cut down providing fresh leaves for animal feed.
Once pollarding is begun ongoing management will be needed and will be preferable to re-pollard. This is because the stems that re-grow will always have relatively weak unions with the main stem. While they are small this is not a problem, but if allowed to grow sufficiently they will eventually become heavier prone to splitting.
Pollarding is usually carried out in the winter months. Pollarding in early spring when the buds are starting to show, or after the leaves have started to appear, is detrimental to the trees health.