Abstract
Since 1972, an experimental management system for Japanese oak (Quercus mongolica var. grosseserrata) has been studied in a natural Japanese oak forest, approximately 200ha in area, in the Kyushu University Forest in Hokkaido. The management system was based on the clearcutting system in tongue-shaped blocks surrounded by shelterbelts; rotation was 150 years. The silvicultural process in this management system was designed to produce high-quality timber. For 30 years between 1973 and 2002, the number of first-year oak seedling established by the silvicultural process averaged 55,000 per ha per year. For 30 years between 1972 and 2002, the area managed averaged 9.11 ha per year. For 30-years, the timber volume derived from thinning and final cutting averaged 198m^3 per year. The revenue obtained by selling this timber averaged 892,000 yen per year. The cost of silvicultural process averaged 557,000 yen per year, excluding the costs of staff and other factors owing to the Kyushu University Forest. Thus the average net revenue per year was 335,000 yen for the 30-years.
