Effect of the inclusion of mushroom values on the optimal management of even-aged pine stands of Catalonia

Abstract

Mushrooms are an important product of the pine stands of the Central Pyrenees of Catalonia. In places where the microclimate is reasonably moist, the value of mushrooms may be clearly higher than the value of timber production. This study examines the optimal economic management for both timber and mushrooms in even-aged Scots pine and Black pine stands in Catalonia. Empirical mushroom yield models were integrated in a stand growth simulator, which was linked with an optimization algorithm to find the optimal management schedule for Pinus sylvestris and Pinus nigra stands on different sites and with different mushroom prices. The results showed that on sites where the potential mushroom yield is high, mushrooms should be taken into account in stand management. Thinning treatments, which usually are unprofitable, were included in the optimal management schedule when mushroom production was included in the analysis. Although thinnings have a negative short-term effect on mushroom yields, their long-term effect is often positive because they reduce stand density to a level that is favorable for mushrooms. At elevations that are suitable for P. sylvestris (900 –1,500 m above sea level), the soil expectation value (SEV) of mushroom yields was commonly 4 –10 times higher than the SEV of timber production. At somewhat lower elevations, where P. nigra dominates, the effect of mushrooms on the optimal stand management was smaller because mushroom yields are typically lower in P. nigra stands.

This study was funded by the research project AGL2008-04435/FOR (Ministerio de Ciencia e Innovación of Spain, Subdirección General de Proyectos de Investigación), the Departament de Medi Ambient i Habitatge of the Generalitat de Catalunya, and the Mediterranean regional Office of the European Forest Institute.