On the Price Formation Mechanism and the Selling Methods of High-quality Hardwoods : A Case Study in the Tokyo University Forest in Hokkaido

Abstract

本論では，量と質の保続を目指して広葉樹優良大径木を育成・生産している東京大学北海道演習林を事例として，優良材の価格形成および販売について経済分析を行った。森林所有者は立木や材を販売する際に，それらの価格を把握する必要がある。そこで，今回広葉樹優良材について，長級，径級，品等，採材高，樹齢等を用いた回帰モデルを作成し，価格の推計を行うとともに，材の価格形成要因について考察した。その結果は，おおむね市場の動向を裏付けるものであったが，価格の予測を行うに耐え得るかどうかは不明である。また，樹種によっては，枯損が価格に与える影響が正に働くことが明らかとなった。次に，優良材の最適な販売方法について検討を行った。そして，優良材の適正な価値は，立木の段階では判断しにくく，素材においても多数の買い手の存在によってより実現可能であり，市売委託販売がもっとも適した販売方法であることを明らかにした。This paper reports on the economic analysis of logging and selling high-quality hardwoods in the Tokyo University Forest in Hokkaido. The forest has been managed by the selection cutting system, so-called stand based forest management, and it has been producing large, high-quality timber under sustainable conditions. Standing timber that is going to be felled is selected on the basis of tree vigor. In practice, over half of the high-quality standing timber was logged after its death. But the number of high-quality logs obtained from a tree decreases when it dies, and every species has a different rate of grade decrease. The prices of high-quality logs were analyzed by the hedonic model using data on length, diameter, grade, felling height, and tree age as explanatory variables. The result of analysis is not sufficiently accurate to predict log price. On the other hand it was found that in some species the prices of logs were increased by the effect of death. The best way to sell high-quality hardwoods is to sell them in a roundwood auction market after cross-cutting into logs, because the value of a log can be estimated more accurately than that of standing timber. In addition, a forest owner cannot accurately know the log price before the sale, so he cannot obtain an adequate price when he sells logs in a market with a few buyers