![]() Cut back to a point between nodes (leaf attachment points) on the shoot, that is, somewhere on the stem between the places where one or more leaves or side shoots attach to the main shoot. The initial pollard cuts are topping or heading cuts made on small diameter shoots during the dormant season. If you plan on cutting the pollards every two or three years for fodder production, the branches and pollard heads will need to be further apart vertically and horizontally. If you plan on cutting the pollards every year the branches can be closer together. To develop an effective pollard, one must use the first several years of a tree’s life to develop the overall form and architecture desired-forming scaffold branches at the right heights and spacing, for example. This is critical because when the full shoot diameter at the time and place of cutting contains living wood throughout, there is no heartwood available for infection by decay organisms, the living wood can resist decay effectively until it calluses over, and the wound can callus over in a short time, reducing the chance of decay entering the stem. Andrew reiterated that pollarding is a training system that involves planning far ahead: one must start pollarding when the tree is young, or at least when the shoots to be pollarded are young and vigorous and have not yet developed heartwood. These lindens are pollarded to keep the trees to a size and shape that meets the aesthetic goals of this garden. I recently connected with Andrew Lyman, a board certified Master Arborist with years of experience managing a grove of pollarded European lindens ( Tilia cordata) at an Italian Water Garden in southeastern Pennsylvania. The larger the stem diameter when the cut is made, the longer it takes for callus tissue to cover the wound and the more chances When heartwood is exposed in this way, it tends to rot. Most often the heading cut is made on a fairly large shoot that has already developed heartwood to one degree or another. ![]() This practice consists of what arborists call “heading cuts,” where one cuts a branch or stem back to a stub, or to a lateral branch too small to assume the “terminal role” for that shoot. In my travels around the world since we started work on this book, I have seen plenty of examples of people “pollarding” when really what they were doing was “topping”-or in some cases simply hacking at-trees and shrubs without understanding the physiological consequences that follow.Īny arborist worth their salt seriously frowns on topping trees and letting them resprout, despite its frequency in, for example, Virginia (see Fig. However, Mark and I have heard from various people and authors that pollarding is a training system not a pruning technique, but these same people gave us precious little practical information to go on for how one trains a pollard in the first place. Indeed, that is even how some people in Austria practice it (Figure 1). Ultimately a landscape which carries the full range of interconnecting growth stages, including coppice, will yield the greatest opportunities for biodiversity and conservation.Pollarding would seem to be the same as coppicing, except elevated above the ground. Some aspects of the coppice cycle can be delivered by alternative silvicultural methods, or manipulated in order to add missing old-growth characteristics. Re-coppiced stools showed variable survival, but with usually sufficient regrowth to restore the former canopy, supplemented by natural regeneration. Re-coppicing after 50–100 years of neglect has shown moderate success, with most early successional species recovering well and restoring species and functional biodiversity, assuming available sources in the surrounding landscape. At the same time, most aging coppices are too young to develop any significant old-growth and saproxylic features of conservation significance. ![]() Accumulated litter and depositions of atmospheric nitrogen also threaten a future eutrophic response. ![]() When abandoned or converted to high forest, coppice vegetation shows increasing homogenisation and may lose some rare plant species, although shade-tolerant plants are largely unaffected. Some species are considered of such high conservation value that they justify continued coppicing. Contemporary trends in forestry towards continuous cover management have major implications for cosmopolitan and early-successional groups of species which rely on short rotations and regular disturbance, such as heliophilous plants and those with persistent seed, insectivore songbirds, butterflies, and many invertebrates requiring understorey flowering, pollen and nectar. Coppice management has a long and ancient tradition in Europe, but still comprises over 14% of the forest area despite showing catastrophic declines in the past century.
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