Pollarding is a pruning technique where the main bulk of a tree is removed all the way down to a prescribed height (normally back to the main trunk or thereabouts). This encourages multi-stem branching from the point where the cuts are made.
The main benefit of pollarding a tree is an increased lifespan, mainly due to having less weight and windage in the top part of the tree. It also helps light to pass through the tree without completely removing it. 
Pollarding has been a common technique in Europe since medieval times. It is a great way to keep a tree at a predetermined height and once started, pollarding should be repeated on a cyclical basis always retaining the initial pollard point.
SPC Tree Services have conducted a number of pollards of various sized trees. Should you require this type of work done then please get in touch today.