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selection cutting
Selection cutting is the silvicultural practice of harvesting trees in a way that moves a forest stand towards an uneven-aged or all-aged condition, or 'structure'. Using stocking models derived from the study of old growth forests, '"Selection cutting"', also known as 'selection system', or 'selection silviculture', manages the establishment, continued growth and final harvest of multiple age classes (usually three) of trees within a stand. A closely related approach to forest management is Continuous Cover Forestry (CCF), which makes use of selection systems to achieve a permanently irregular stand structure.〔Helliwell, R., and E. R. Wilson. (2012). Continuous cover forestry in Britain: challenges and opportunities.Quarterly Journal of Forestry 106(3): 214-224 ()〕
Selection cutting or systems are generally considered to be more challenging to implement and maintain than even-aged silviculture, due to the difficulty of managing multiple age classes in a shared space, but there are significant ecological benefits associated with it. Uneven-aged forests generally exhibit higher levels of vertical structure (key for many species of birds and mammals), have higher levels of carbon sequestration, and produce a more constant flow of market and non-market forest resources than even-aged forests. This method of silviculture also protects forest soils from the adverse effects of many types of even-aged silviculture, including nutrient loss, erosion and soil compaction and the rapid loss of organic material from a forested system. Selection silviculture is especially adept at regenerating shade-tolerant species of trees (those able to function under conditions of low solar energy), but can also be modified to suit the regeneration and growth of intolerant and mid-tolerant species.
==Disputed term==
''Selection cutting'' is often confused with "selective" cutting, a term synonymous with the practice of highgrading (the removal of the best trees in a forest, often with a disregard for the future of the residual stand). Often the latter term is used by foresters or loggers to imply the former (which has a generally positive connotation in forestry circles) and mislead landowners into stripping their woodlot of its most valuable timber. Used correctly, the term 'selection cutting', 'selection system', or 'selection silviculture' implies the implementation of specific silvicultural techniques—usually either 'single tree selection', 'group selection' or a combination of the two—to create an uneven-aged or all-aged condition in a forest stand, one more akin to a late successional or 'climax' condition.〔McEvoy, T.J. 2004. Positive Impact Forestry - A Sustainable Approach to Managing Woodlands. Island Press, New York, DC. 268p.〕
Partly as a result of such confusion, the German term ''Plenterwald'' has been used in English for the term selection cutting.〔6 TECHNICAL CONDITIONS AND REQUIREMENTS FOR ACHIEVING SUSTAINABLE FOREST MANAGEMENT http://www.fao.org/docrep/003/x4109e/X4109E07.htm〕 Increasingly, especially in Britain, Ireland and elsewhere in Europe, the term Continuous Cover Forestry (CCF) has been adopted to embrace an approach to stand management that most often employs selection systems to achieve a permanently irregular stand structure. 〔Helliwell, R., and E. R. Wilson. (2012). Continuous cover forestry in Britain: challenges and opportunities..Quarterly Journal of Forestry 106(3): 214-224 ()〕
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