Effect of Saw Pattern and Diametric Grades on the Yield in Lumber of Araucaria angustifolia

ABSTRACT This research was developed in order to assess the effect of aleatory breakdown and optimized breakdown systems of the logs of A. angustifolia, using different diametric classes to obtain lumber in a small sawmill. For this, 60 logs were selected, cubed and separated in three diameter classes, with 20 logs each, which were additionally divided in two lots of 10 logs, being the first lots subjected to aleatory breakdown, and the second for optimized breakdown. The results indicated that the optimized breakdown was satisfactory; in addition, the diametric classification caused an increase in yield lumber on both breakdown systems. The adjusted models for the yield prediction due to the taper of the logs were significant and satisfactory, especially in the optimized breakdown system that had high determination coefficients adjusted, regarding the aleatory breakdown system.