PITH ECCENTRICITY IN Eucalyptus CLONE STEMS CULTIVATED ON DIFFERENT TOPOGRAPHIES

Abstract

This work evaluated the pith eccentricity in stems of four Eucalyptus clone trees, with two years of age, cultivated on flat, soft slopped and high slopped land.  From each stem, a 5 cm disc was cut at 1.10 m of height above ground. With a standard placed on the wood disc, it was marked its geometrical centre and, consequently, the distance from the pith (D). The eccentricity of the pith was determined by the relationship between D and the average diameter of the disc. The results showed that: i) the eccentricity of the pith occurred in all clones, changing from 2.53% to 4.55%; ii) upright trees, planted on flat land, soft and on heavy slopped terrains presented eccentric pith; iii) for the trees planted on slopped terrains it was observed a tendency of the piths to be positioned at the side of the discs opposite to the slope of the terrain; iv) the occurrence of the eccentric piths into the stems of all clones and topographies studied suggests the formation of tension wood.