EFFECT OF THINNING IN THE END SPLITS OF THE LOGS OF Eucalyptus grandis W. Hill ex Maiden

Abstract

http://dx.doi.org/10.5902/1980509813336The study was undertaken to evaluate the effect of thinning in the end splits of the logs of the Eucalyptusgrandis at 18 years of age. There was analyzed a thinning experiment, located in the northern coast of RioGrande do Sul State, Brazil, installed in randomized blocks with four repetitions. The seven treatments weredefined according to the number of thinnings applied and ranged from zero to six interventions. The treeswere selected, in each treatment, on the basis of the Assmann’s dominant diameter and the central diameterof tree, being referred to as dominant and central trees, respectively. After cutting down the selected thelogs were located between the DBH (diameter at breast height) and 25% positions, 25% and 50%; 50% and 75%; 75% and 100% of the commercial height, for the end split study. The results indicate that the averageend splits of the logs in the dominant and central trees was higher at the second log sampled, suggestingthat sectioning should be carried in conjunction with techniques that minimize the growth stress, especiallywhen this is performed near the half of the commercial height. The thinning induced variation in the logsend split, both for dominant and central trees; however, there was no clear positive or negative trend,leading to the conclusion that changes in growth rate did not affect these parameters uniformly.

Keywords

• eucalipto
• tratos silviculturais
• qualidade da madeira