Determination of thinning optimum age and intensity in a Eucalyptus dunnii stand

Abstract

Eucalypts wood has been traditionally used for paper and energy production in Brazil. Recently several species of this genus have been serving other purposes, such as the production of panels, plywood, veneers and furniture. These more value-added wood products require different silvicultural systems, with longer rotation periods and the introduction of pruning and thinning treatments. This study aimed to evaluate the effects of three different thinning intensities on basal area and volume growth of Eucalyptus dunnii stands at two different ages. The thinning treatments were applied either at the third and or the fourth year. The experimental plots had average basal area of 20 m²/ha and 25 m²/ha at the age of 3 and 4, respectively. These forest stands were thinned to 16, 14 and 12 m²/ha of basal area. Volume and basal area growth were analysed at the age of 7 years. The results indicated that the experimental plots undergoing thinning treatments of 14 m²/ha at age 3 were able to equal their growing stock to those of the control treatments after three years.