INFLUENCE OF PRUNING ON WOOD DENSITY OF FIRST THINNING OF Pinus elliottii Engelm

Ana Cristina Schilling Paulo Renato Schneider Clóvis Haselein César Augusto G. Finger About the authors

ABSTRACT

This work tried to evaluate the influence of different intensities of pruning on the density of air-dried wood and the basic density of the first thinning wood of Pinus elliottii Engelm. In order to achieve this goal, three replacement blocks were used randomly, set on a ten-year old stand, where five treatments were analyzed: T1 - with no pruning; T2 - dry pruning; T3 - 40% pruning ; T4 - 50%; and T5 - 60% of the total canopy height, respectively. In each experimental unity, three trees were sampled. “The density of air-dried wood was obtained from specimens of 4 x 4 x 20 cm, and the basic density was determined through disks taken at 0.10 meters of height from the sample trees. The data analysis of density of air-dried wood did not show any significant linear regression, at a 5% significance level. Comparison of treatment means, made through orthogonal contrasts, did not show any significant differences between the treatments either. The wood basic density showed some growing trend throughout the ages in all of the treatments, which was proved through regression equation fitting. In T1 and T3 treatments, the basic density seems to have kept stabilized around 8 years old, while in the others it still reveals increasing throughout the ages.

Key words:
Pinus elliottii; pruning; density of wood; wood quality

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