Dimensional Stability and Technological Performance of 13-Year-Old Simarouba amara Aubl. Thinning Wood: Pathways to High-Value Product Development

The valorization of wood derived from thinning operations in tropical plantations represents an alternative to enhance the sustainability and profitability of forest production systems. This study evaluated the hygroscopic, physical, and machining properties of 13-year-old Simarouba amara Aubl. thinning wood obtained from a plantation established in the Peruvian Amazon. Two planting spacings (2 × 2 m and 3 × 3 m) and three longitudinal stem positions (base, middle, and apex) were analyzed using a factorial design and generalized linear mixed models. Planting density and longitudinal position significantly influenced (p < 0.05) most of the evaluated properties. The saturated moisture content increased from 96.17% at the base to 135.42% at the apex, whereas basic density decreased from 0.45 to 0.30 g cm−3. Volumetric shrinkage ranged from 10.19% to 14.81%, and the dimensional stability index varied between 1.66 and 1.91. The first principal component (PC1) explained 98.4% of the total variance and clearly differentiated the treatments. The wood exhibited excellent performance in planing and molding, good performance in drilling, and fair performance in turning, indicating strong potential for the manufacture of higher value-added products and for sustainable utilization in tropical plantation forests.