Morfologia radial das fibras do lenho de quatro espécies do gênero Eucalyptus L'her

Abstract

The variability inside the tree in the radial sense is fundamental for the technological characterization of the wood. Because of the absence of a universal variation tendency, the objective of this research was to evaluate the behavior of the fibers in the medulla-bark direction in the wood of four Eucalyptus species from Rio Grande do Sul state. Three individuals of Eucalyptus benthamii, E. dunnii, E. grandis and E. saligna, totaling 12 wood discs. From each disc, specimens were removed in the medulla-bark direction heartwood, peripheral core and sapwood and macerated blades were made to determine the radial variation of fibers. For the four species an increase in the length of the fibers from the heartwood to the sapwood was observed. There was no trend of stabilizing fiber growth at the core, peripheral core and sapwood positions, which recommended keeping the trees in the field for a longer period.