Sustainability in spruce and mixed-species stands

Abstract

It is important to find and develop forest management strategies that do not result in the depletion of soil nutrient pools and at the same time are financially competitive in relatively short-term, 1–2 rotations. Mixed-species stands, which combine the elements of fast growing, highly productive softwood and more slowly growing, high quality hardwood, appear to be an interesting alternative in this respect, one worthy of further investigation. Among the mixtures of trees tried out in southern Swedish forestry thus far the Norway spruce/oak-system developed by Erik St”l and his heirs at their estate in Jämjö, Southeastern Sweden, appears promising. According to the owners, the mixed-species stands perform well financially. The management system is well defined and aims at the production of veneer-quality oak wood with Norway spruce as an economic buffer early in the rotations (Ståål 1986). We decided to investigate both the biogeochemical and the economic sustainability of the mixed-species stands there as well as of the adjacent Norway spruce monocultures. Matters of biodiversity are as yet to be investigated. It is reasonable, however, to expect there to be better possibilities for maintaining a high level of biodiversity in mixed spruce/oak forest stands than in Norway spruce monocultures.