YIELD IN SAWN WOOD AND RESIDUE UTILIZATION OF Qualea paraensis DUCKE AND Erisma uncinatum WARM

The study was developed in Nova Maringá - MT. The objectives of this work were to evaluate the sawn timber yield, the use of wood residues and the quantification of products for the species Qualea paraensis (cambará) and Erisma uncinatum (cedrinho) in three diametric classes: Class A - 40.0 to 49.9 cm; Class B - 50.0 to 59.9 cm; Class C - 60.0 to 69.9 cm. Four replicates per class were evaluated, totaling 12 logs per species of varied lengths. The sawn timber yield did not show a statistical difference between diametric classes for both species. Average yield for Qualea paraensis was equal to 43.97% and for Erisma uncinatum, 42.05%. The residues use increased the total yield in 4.40% and 6.52% for Qualea paraensis and Erisma uncinatum, respectively. For Erisma uncinatum, the sawed products with the highest production were the board in the primary unfolding and the short board in the residues use. As for Qualea paraensis, there was more production of rafters and short battens in the same processes

Effect of Age on Heartwood Proportion, Color, Chemical Composition, and Biological Resistance of Teakwood

Teakwood from fast-growth plantations is commercialized at increasingly younger ages for economic reasons. However, wood features are influenced by the age of the tree. This study examined how age affects heartwood proportion, color parameters, chemical composition, and natural teakwood durability. Trees with 5, 10, 15, and 20 years of fast-growth at commercial plantations located in Mato Grosso, Brazil were evaluated. The base diameter of the trees ranged from 13.1 (5 years) to 28.3 cm (20 years), and the heartwood percentage increased from 16.3 to 60.0%, respectively. The color parameters in the CIELab system indicated that wood became darker and more saturated, and the predominance of yellow color decreased compared with red as age advanced. The total extractive content ranged between 7.4 (5 years) and 9.6% (15 years), without a clear trend of age affecting the extractive content. The extractives from five-year-old wood were mainly composed of tectoquinone (43.3%), phthalic acid (19.1%), and 1,3-indandione (9.2%), while those from 20-year-old wood were mainly composed of tectoquinone (60.7%), lapachol (13.8%), and phthalic acid (9.7%). Teakwood can be classified as resistant (5 years) to very resistant (20 years) after being submitted to an accelerated decay test