Pollarding trees: which species, when

Pollarding is a pruning technique in which a tree is cut back to its main trunk or primary framework branches on a regular schedule, typically annually or biennially, to produce a mass of new vigorous shoots (the "pollard head") at a fixed height above ground. Per the Royal Horticultural Society,.

Pollarding is a pruning technique in which a tree is cut back to its main trunk or primary framework branches on a regular schedule, typically annually or biennially, to produce a mass of new vigorous shoots (the "pollard head") at a fixed height above ground. Per the Royal Horticultural Society, pollarding has been practiced in Europe for centuries to produce a sustained crop of flexible shoots (for basket weaving, charcoal, animal fodder) while keeping trees at a manageable height. In modern ornamental horticulture, it is used to:

• Maintain a specific tree size in a constrained space
• Produce dramatically large, exotic-looking foliage on species with especially large leaves (Paulownia, Catalpa, Ailanthus)
• Create formal avenue effects (plane trees in European cities)
• Confine vigorous trees to small urban sites

How pollarding differs from topping

These are not the same. Per Penn State Extension, topping is the haphazard removal of large-diameter branches at random positions, leaving stubs that cannot close over, exposing the tree to decay. Pollarding is a systematic technique applied to appropriate species at a specific height, maintained on a regular schedule, with cuts made to established pollard heads that have developed a callus ring.

Do not conflate the two. Topping damages trees. Pollarding, on appropriate species with correct technique and consistent maintenance, does not.