Growth and yield as an indication of sustainable forest management in industrial plantations : evidence for sustainable plantation forestry

Abstract

Evidence from growth and yield measurements of successive rotations of industrial plantations is reviewed. The objectives, methodologies and limitations of the evidence is discussed and suggestions made concerning appropriate aims and methods for such work. Reported comparisons of forest productivity between successive rotations of Pinus radiata, P. patula, P. taeda and P. elliottii demonstrate that yield declines can occur when inappropriate forestry practices are applied to specific sites. Identification and understanding of these effects appear to have been initiated by data from simple growth comparisons between rotations. In these studies the observation of decline in successive rotations was followed by empirical and process studies to establish a cause. This in turn leads to modification of forestry practice to correct the decline. These experiences suggest two important objectives for monitoring of growth and yield in successive rotations; firstly, as a physical check that the actual trend in yield between rotations is consistent with expectation and secondly, as a tool to elucidate the cause of observed change in productivity between rotations. The chosen methodology must relate to the specific objective of the study. The lack of comparative data from successive rotations of fast-grown Eucalyptus plantations is highlighted.


Southern African Forestry Journal No.195 2002: 47-56