Commercial clones of Eucalyptus at different ages for bioenergetic use of wood

The objective of this study was to evaluate chemical and physical characteristics of the wood of commercial clones of Eucalyptus at different ages, correlate them to the Pilodyn® pin penetration, as well as their bioenergetic use. Two commercial clones of Eucalyptus were sampled (I220 and I144), at two ages (49 and 61 months). The dendrometric characteristics of the trees were evaluated; in the wood basic density, chemical composition, higher and lower calorific values, energetic density and carbon stock were evaluated. Furthermore, the wood was subjected to thermogravimetry in inert atmosphere. A completely randomized design (CRD) was used, arranged in a double factorial design 2 × 2 with 4 replicates, besides an analysis of simple linear correlation between the Pilodyn® pin penetration and the characteristics analyzed. Clone I144 showed lower values for basic density, energetic density and carbon stock in wood than clone I220. However, clone I144 stood out in growth characteristics (DBH and total height). The 61-month wood is more suitable for charcoal production, as it presented the smallest holocellulose percentage and volumetric content and the greatest total lignin content. The 49-month wood may be intended for the direct production of energy as firewood. It was possible to observe significant correlations between the Pilodyn® pin penetration and the characteristics evaluated, both in the trees (DBH and total height) and in the wood (basic density, energetic densities and carbon stock).