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Silviculture is the practice of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values. The name comes from the Latin ''silvi-'' (forest) + culture (as in growing). The study of forests and woods is termed silvology. Silviculture also focuses on making sure that the treatment(s) of forest stands are used to preserve and to better their productivity.〔Hawley, R.C. and D.M. Smith. ''The Practice of Silviculture. ''6th edition. New York: John Wiley & Sons Inc., 1954. Print.〕 Generally, silviculture is the science and art of growing and tending forest crops, based on a knowledge of silvics, i.e., the study of the life history and general characteristics of forest trees and stands, with particular reference to locality factors (Ford-Robertson 1971).〔Ford-Robertson, F.C. (Ed.) 1971. Terminology of Forest Science, Technology, Practice and Products. English language version. Soc. Amer. For., Washington DC. 349 p.〕 More particularly, silviculture is the theory and practice of controlling the establishment, composition, constitution, and growth of forests. No matter how forestry as a science is constituted, the kernel of the business of forestry is silviculture, as it includes direct action in the forest, and in it all economic objectives and technical considerations ultimately converge (Köstler 1956).〔Köstler, J. 1956. Silviculture. Transl. M.L. Anderson from "Waldbau" (1949). Oliver and Boyd, Edinburgh and London, U.K. 416 p.〕 The kernel of silviculture is regeneration. Suggestions for how best to go about the job, presented by Jeglum et al. (2003),〔Jeglum, J.K.; Kershaw, H.M.; Morris, D.M.; Cameron, D.A. 2003. Best forestry practives: A guide for the boreal forest in Ontario. Natural Resources Canada, Can. For. Serv., Sault Ste. Marie ON, co-published by Ont. Min. Nat. Resources, Sault Ste. Marie ON. 110 p.〕 though aimed primarily at the boreal forest in Ontario, merit wider consideration. The 110-page publication describes Best Management Practices, first by general principles, then by sensitive sites. Illustrations are plentiful and are well chosen to complement this excellent text. To some the distinction between forestry and silviculture is that silviculture is applied at the stand level and forestry is broader. For example, John D. Matthews says "complete regimes for regenerating, tending, and harvesting forests" are called "silvicultural systems".〔John D. Matthews, Silvicultural Systems. Oxford Science Publications. 1991, ISBN 9780198546702〕 So active management is required for silviculture, whereas forestry can be natural, conserved land without a stand level treatment being applied. A common taxonomy divides silviculture into regenerating, tending and harvesting techniques. ==Silvicultural systems== Various “silvicultural systems” have been devised to effect regeneration. In British Columbia, for example, 4 silvicultural systems are used: (1) clearcutting, (2) seed-tree, (3) shelterwood, and (4) selection. Clearcutting, though the most efficient and least expensive way of harvesting wood, may create difficulties that impede the establishment of regeneration. Obtaining natural regeneration of white spruce in Alaska and boreal Canada after clearcutting has proved to be difficult (Lees 1970, Stiell 1976, Greene et al. 1999).〔Lees, J.C. 1970. Natural regeneration of white spruce under spruce–aspen shelterwood, B-18a Forest Section, Alberta. Can. Dep. Fish. For., Can. For. Serv., Ottawa ON, Publ. 1274. 14 p.〕〔Stiell, W.M. 1976. White spruce: artificial regeneration in Canada. Dep. Environ., Can. For. Serv., Ottawa ON, Inf. Rep. FMR-X-85. 275 p.〕〔Greene, D.F.; Zasada, J.C.; Sirois, L.; Kneeshaw, D.; Morin, H.; Charron, L.; Simard, M.-J. 1999. A review of the regeneration dynamics of North American boreal forest tree species. Can. J. For. Res. 29:824–839.〕 In addition, white spruce that are outplanted in the open in severe boreal climates without a modicum of protective “nursing” can stagnate for decades (Sutton 1992).〔Sutton, R.F. 1992. White spruce (''Picea glauca'' () Voss): stagnating boreal old-field plantations unresponsive to fertilization and weed control. For. Chron. 68:249–258.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Silviculture」の詳細全文を読む スポンサード リンク
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