A theory of red pine (Pinus koraiensis) management for both timber and commercial seeds

Abstract

Red pine (Pinus koraiensis), is a commonly distributed species of tree in northeastern China. The wood is used for manufacturing purposes as usual, and the seeds are used as a source of delicious food and for medical applications. If the top of the tree is removed at a mature age, seed production is much enhanced. In this article, we derive optimal harvesting rules for such multiple use management of red pine trees. We give optimality conditions for cutting off the top of the tree, the intensity of removal, and the optimal date for the final felling. The two harvesting dates will indirectly determine the optimal length of commercial seed production. We also derive comparative static results on how the rotation periods and the intensity of removal changes, as a function of prices and the interest rate. The theory is also applicable to the economic management of seed orchards, where the practice of cutting off the top of the tree is used, all over the world, to induce seed production.