Usage of the pruned log index for loblolly pine (Pinus taeda) and slash pine (Pinus elliottii)

Abstract

The assessment of the quality of clearwood produced in pruned plantations of pine is necessary, especially to set price and know the utilization potential. The pruned log index (PLI), index used in Chile and New Zealand to characterize the quality of the logs, is a function of measurable variables of each log as diameter with defects, diameter 1.3 m from the largest end and the ratio between the cylinder volume common to the entire length of the log and the scaling volume through the method Smalian. This study aims at evaluating the ITP usage for slash pine (Pinus elliottii) logs at the age 24 years and loblolly pine (Pinus taeda) at 19, harvested
in the regions of Ibaiti, Paraná, and Itapeva, São Paulo. The PLI values did not exceed 2.3, which  indicates that there is little clearwood on the logs. This has been proven through the veneering results, in which the potentially clear volume in relation to the log volume ranged between 52% and 55%, but 10.3% at the maximum, was turned into clearwood veneer. The slicing procedure in the lathe proved to be suitable, since it allowed the diameter of the knotty core to be measured as soon as the knot came out. The PLI showed itself as applicable for the Brazilian conditions.