Coppice management
Well maintained coppice stools can, in principle, be worked indefinitely, although this is usually limited by nutrient availability and stool mortality. Oak coppice can be economically maintained for up to 130 years cut on a typical rotation of 6-30 years. An alternative method of management is coppice with standards. Here a single shoot from each stool is not coppiced on the normal rotation but left to develop into a timber quality stem. This method has historically been the standard practice and ancient coppice stools (several hundred years old) are common. Coppice systems (without standards) have the benefit of minimal soil damage during harvest, a reduced need for weed management, physical protection of the site, negligible risk of windthrow and where markets for the product exist, a cash return for the landowner. Nevertheless, concerns may still exist over potential damage to archaeological remains due to root penetration.
Coppice roots
The long life of structural tree roots may provide a stabilising lattice to support the form of an earthwork such as a bank. Where appropriate and possible, coppice silviculture may offer long-term soil stability with reduced risk of windthrow compared with high forest management. Knowledge of the rooting habits, water requirements and the environmental chemistry under different tree species can also be used to reduce risks of some potential impacts.
Coppice root systems consist of finer, less extensive roots than standard trees that are subjected to some degree of checking following coppicing. With their long life potential, coppice stools may offer an alternative to grass where grazing or intensive management is not an option, or to standard tree cover where associated operations and larger, deeper rooting are less desirable.
The primary functions of roots is to provide nutrients, water and support for the above ground component of the plant. As a direct result of this function, the above-ground tree biomass is directly related to the root biomass and vice versa. The “root:shoot ratio” is a relatively constant value but will vary slightly with species, site conditions and silviculture. It is believed that the process of pruning reduces the surface area of the tree available for photosynthesis that in turn lowers the total amount of carbohydrates available to feed the root system. Once the root reserves are used, the excess root will die until the ratio is re-established.
Further information on coppice roots can be found on the Short Rotation Coppice page.
