PHYSICO-MECHANICAL PROPERTIES AND GROWTH CHARACTERISTICS OF PINE JUVENILE WOOD AS A FUNCTION OF AGE AND PLANTING SPACING

ABSTRACT Pinus forests have been implanted in the South of Brazil since 1960s different spacing and harvested shorter terms to increase wood yield. Reducing rotation period changing forest plantations can influence wood’s physical mechanical properties, as they are younger trees that do not yet a significant amount mature their composition. In this context, research aimed study three levels planting (3.0 × 2.0 m, 4.0 m) two ages (13 15 years old) on growth characteristics physical-mechanical properties wood, well relationship between them. Apparent density, latewood percentage, rings per inch, strength stiffness static bending compression parallel grain, shear were evaluated. The evaluated spacings did cause statistically changes juvenile taeda L. wood. studied apparent density. However, cutting age from 13 significantly increased There was correlation tree strength, compression, around 0.500 R2, which suggests parameter be used assist estimating those properties. L classified structural class C20 for years-old classes C25 C30 trees, according NBR 7190/97 requirements.