摘要:High-value hardwood species such as monarch birch (Betula maximowicziana) and castoraralia (Kalopanax septemlobus) are important economic and ecological elements of cooltemperate mixed forests in northern Japan. This article presents the single-tree managementsystem for high-value timber species as practised for 50 years at the University of TokyoHokkaido Forest. Nearly 2000 valuable broad-leaved trees meeting the size and quality criteriahave been registered as ‘superior trees’, and their status is periodically monitored for timingof harvest. A case study was conducted using 2105 inventory plots to characterize the standtypes in which superior trees occur. A total of 57 superior trees of 11 broad-leaved specieswas found in 2.2% of the inventory plots. The results indicated that superior trees generallygrew in mature species-rich stands. Superior trees of some species may have promoted theirabundance by dispersing relatively more seeds to the surroundings. Single-tree managementfacilitates the sustainable use of high-value timber species by explicitly monitoring thenumbers, attributes and locations of superior trees, and contributes to conserving standstructural diversity through protection of these large-sized canopy trees, which promotesecological values such as biomass and carbon storage, species diversity, seed abundance andbird habitat. The production of fancy wood from superior trees earns significant incomethrough extremely high log prices (maximum > 20,000 USD m–3).
关键词:Auction market;fancy wood;high-value tree species;single-tree registry system;superior tree;The Universityof Tokyo Hokkaido Forest