Technical assessment of girdling and incorporation of chainsaw in Eucalyptus grandis trees aiming to greater quality production of lumber.

This work aimed to evaluate two intervention techniques in a stand of Eucalyptus grandis Hill ex Maiden, by prolonged girdling treatments and chainsaw sword insertion to the core of tree, in two distinct periods, 70 and 100 days. These interventions aimed to minimize defects caused by the release of growth stress of Eucalyptus grandis during the sawing of logs. In order to that, we cut down 25 trees in a 20 years old plantation of Eucalyptus grandis , we used 5 trees for each assessed treatment. As parameter of comparison, we quantified the number of boards that had cracks in the end, the crack index (IRT%) of boards and the yield of lumber (R%). The evaluated techniques revealed statistical differences by Tukey test, with a reduction of up to 67.40% of boards that had end cracks. The yield was satisfactory for trees that had interventions, providing less loss of wood due to heading, mainly for chainsaw insertion technique to the core of trees, with total cutting after 100 days.Este trabalho teve como objetivo avaliar duas técnicas de intervenções em um povoamento de Eucalyptus grandis Hill ex Maiden, através dos tratamentos de anelamento prolongado e a inserção do sabre de motosserra até a medula da árvore em dois períodos distintos, 70 e 100 dias. Essas intervenções, por sua vez, tiveram o objetivo de minimizar os defeitos provocados pela liberação das tensões de crescimento da madeira de Eucalyptus grandis durante o desdobro das toras. Para isto, foram derrubadas 25 árvores de um plantio de Eucalyptus grandis com 20 anos de idade, em que, foram utilizadas 5 árvores para cada tratamento avaliado. Como parâmetro de comparação, quantificou-se o número de tábuas que apresentaram rachaduras na extremidade, o índice de rachadura de extremidade (IRT%) e o rendimento em madeira serrada (R%). As técnicas avaliadas apresentaram diferença estatística entre si pelo teste de Tukey, com redução de até 67,40% de tábuas que apresentaram rachaduras de extremidade. O rendimento mostrou-se satisfatório para as árvores que tiveram intervenções, proporcionando menos perda de madeira na forma de destopo, principalmente para a técnica de inserção do sabre da motosserra até a medula das árvores com abate após a 100 dias.AbstractTechnical assessment of girdling and incorporation of chainsaw in Eucalyptus grandis trees aiming to greater quality production of lumber. This work aimed to evaluate two intervention techniques in a stand of Eucalyptus grandis Hill ex Maiden, by prolonged girdling treatments and chainsaw sword insertion to the core of tree, in two distinct periods, 70 and 100 days. These interventions aimed to minimize defects caused by the release of growth stress of Eucalyptus grandis during the sawing of logs. In order to that, we cut down 25 trees in a 20 years old plantation of Eucalyptus grandis , we used 5 trees for each assessed treatment. As parameter of comparison, we quantified the number of boards that had cracks in the end, the crack index (IRT%) of boards and the yield of lumber (R%). The evaluated techniques revealed statistical differences by Tukey test, with a reduction of up to 67.40% of boards that had end cracks. The yield was satisfactory for trees that had interventions, providing less loss of wood due to heading, mainly for chainsaw insertion technique to the core of trees, with total cutting after 100 days.Keywords: Yielding; unfolding; growth stress

AVALIAÇÃO DAS TÉCNICAS DE ANELAMENTO E INSERÇÃO DE SABRE EM ÁRVORES DE Eucalyptus grandis VISANDO MAIOR QUALIDADE DA MADEIRA SERRADA

This work aimed to evaluate two intervention techniques in a stand of Eucalyptus grandis Hill ex Maiden, by prolonged girdling treatments and chainsaw sword insertion to the core of tree, in two distinct periods, 70 and 100 days. These interventions aimed to minimize defects caused by the release of growth stress of Eucalyptus grandis during the sawing of logs. In order to that, we cut down 25 trees in a 20 years old plantation of Eucalyptus grandis , we used 5 trees for each assessed treatment. As parameter of comparison, we quantified the number of boards that had cracks in the end, the crack index (IRT%) of boards and the yield of lumber (R%). The evaluated techniques revealed statistical differences by Tukey test, with a reduction of up to 67.40% of boards that had end cracks. The yield was satisfactory for trees that had interventions, providing less loss of wood due to heading, mainly for chainsaw insertion technique to the core of trees, with total cutting after 100 days.Este trabalho teve como objetivo avaliar duas técnicas de intervenções em um povoamento de Eucalyptus grandis Hill ex Maiden, através dos tratamentos de anelamento prolongado e a inserção do sabre de motosserra até a medula da árvore em dois períodos distintos, 70 e 100 dias. Essas intervenções, por sua vez, tiveram o objetivo de minimizar os defeitos provocados pela liberação das tensões de crescimento da madeira de Eucalyptus grandis durante o desdobro das toras. Para isto, foram derrubadas 25 árvores de um plantio de Eucalyptus grandis com 20 anos de idade, em que, foram utilizadas 5 árvores para cada tratamento avaliado. Como parâmetro de comparação, quantificou-se o número de tábuas que apresentaram rachaduras na extremidade, o índice de rachadura de extremidade (IRT%) e o rendimento em madeira serrada (R%). As técnicas avaliadas apresentaram diferença estatística entre si pelo teste de Tukey, com redução de até 67,40% de tábuas que apresentaram rachaduras de extremidade. O rendimento mostrou-se satisfatório para as árvores que tiveram intervenções, proporcionando menos perda de madeira na forma de destopo, principalmente para a técnica de inserção do sabre da motosserra até a medula das árvores com abate após a 100 dias.AbstractTechnical assessment of girdling and incorporation of chainsaw in Eucalyptus grandis trees aiming to greater quality production of lumber. This work aimed to evaluate two intervention techniques in a stand of Eucalyptus grandis Hill ex Maiden, by prolonged girdling treatments and chainsaw sword insertion to the core of tree, in two distinct periods, 70 and 100 days. These interventions aimed to minimize defects caused by the release of growth stress of Eucalyptus grandis during the sawing of logs. In order to that, we cut down 25 trees in a 20 years old plantation of Eucalyptus grandis , we used 5 trees for each assessed treatment. As parameter of comparison, we quantified the number of boards that had cracks in the end, the crack index (IRT%) of boards and the yield of lumber (R%). The evaluated techniques revealed statistical differences by Tukey test, with a reduction of up to 67.40% of boards that had end cracks. The yield was satisfactory for trees that had interventions, providing less loss of wood due to heading, mainly for chainsaw insertion technique to the core of trees, with total cutting after 100 days.Keywords: Yielding; unfolding; growth stress