Studies on the Silviculture Methods of Snow Resisting Stands of Sugi (Cryptomeria japonica D.Don) in Little Snow Districts, West Japan.

Research Project

Project/Area Number	59480061
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	林学
Research Institution	Shimane University
Principal Investigator	MIYAKE Noboru (1986) Faculty of Agriculture, Shimane University, Professor, 農学部, 教授 (30032543) 石井弘 (1984-1985) 島根大学, 農学部, 助教授
Co-Investigator(Kenkyū-buntansha)	ISHII Hiroshi Faculty of Agriculture, Kagoshima University, Professor, 農学部, 教授 (90032557) FUJIE Isao Faculty of Agriculture, Shimane University, Associate Professor, 農学部, 助教授 (00032558) KATAGIRI Shigeo Faculty of Agriculture, Shimane University, Associate Professor, 農学部, 助教授 (00032649)
Project Period (FY)	1984 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥4,000,000 (Direct Cost: ¥4,000,000) Fiscal Year 1986: ¥700,000 (Direct Cost: ¥700,000) Fiscal Year 1985: ¥1,300,000 (Direct Cost: ¥1,300,000) Fiscal Year 1984: ¥2,000,000 (Direct Cost: ¥2,000,000)
Keywords	Snow Resisting Property / Local Variety / Elone Seedlings / Raising Trees Dent By Snow / Eiomass Of Understory
Research Abstract	1. Snow resisting varieties: Some characters of branches were depend on the genetic factors of Sugi clone seedlings. Middle aged varieties were classified as omotesugi( Pacific Type ) and Urasugi ( Japan Sea Type ), and stem form, width of crown, angle and number of branches were measured. The length of secondary branches, the angle, length and weight of needles of Omotesugi larger than those of Urasugi. The characters of twigs of Sugi clone seedlings in Fukui Prefecture belonging to heavy snow districts were also measured. 2. Raising trees bent by snow in winter: The recovery of bent trees after melting of snow was investigated in the two-vears-old plantation. Though the bent trees with large tilt angle recovered slowly, almost bent trees recovered until the end of July. The degree of bending of trees which recovered perfectly for one growing season did not influenced the growth of trees. The root system of snow damaged trees was measured and examined the relation to the process of recovery and the tree growth. Some useful informations for raising trees bent by snow were obtained. 3. The standing crop of understory were measured in various aged Sugi stands. The amount of understory decreased with stand age until the stand were close, and increased gradually as the relative light intensity of the stands increased again because of thinning and pruning. The amount of the standing crop of understory decreased also as the stem-form coefficient decreased.