Distribution of volume with bark in clonal plantations of Gmelina arborea Roxb. in large logs for sawmill, small logs for sawmill, pallets, firewood and waste in two locations in Costa Rica

Abstract

Forest plantation management should be accompanied by evaluation tools that are easy to apply and precise. Cutting tables are an instrument that facilitates the analysis of the products to be obtained, distributing them into the categories of Coarse Sawn Timber (AG), Fine Sawn Timber (AD), Pallet (T), Firewood (L), and Waste (D). Therefore, the study evaluated two Gmelina arborea plantations located in different regions of the country (Southern and Atlantic zones). Information from 105 eight-year-old trees was used. The diameter at breast height (DBH) and height were measured, applying an on-site cutting, which was performed with the Electronic Dendrometer (Criterion RD1000) every 1.5 m. The volume was obtained using Smalian's formula, and the diameters for classification
were AG (≥30 cm), AD (29.9 to 20 cm), T (19.9 to 10 cm), L (9.9 to 5 cm), and D (<5 cm). The volume was grouped by product type and diameter class. In Puerto Jiménez, an average volume per tree of 0.53 m³ was obtained, and 0.61 m³ for Buenos Aires. The volume distribution per tree in Puerto Jiménez according to the product was: 37.96 %, 31.10 %, and 27.35 % for AD, AG, and T, which represent the main products to be obtained from Gmelina. L and D together represented 3.6 % of the total. In the case of Pocora, the main product was AD with 38.5 %, followed by AG (38 %) and T (21 %); L (2 %) and D (0.5 %) were less significant.