Does Spacing Affect The Production Of Clones For Wood Energy Planted In The State Of Rio Grande Do Norte, Brazil?

Silvicultural treatments can significantly influence the productivity and quality of eucalyptus wood. This work aimed to evaluate the influence of plant spacing on the production of wood and wood energy of a clone of Eucalyptus urophylla x Eucalyptus brassiana, at 4.5 years of age, planted in the state of Rio Grande do Norte, Brazil, under different spacing. The volume was measured and discs were collected from three trees, discs were collected and removed in 10 positions of each tree (0%, DBH, 2.5%, 25%, 37.5%, 50%, 67, 5%, 75%, 85.5% and 100%) in the following spacing: 3 m x 0.5 m; 3 m x 1.5 m; 3 m x 3 m; 3 m x 5 m and 3 m x 6.5 m), totalling 15 trees and 150 discs. The wood production from 10 to 50 months of age, the basic density and energy production in the different spacing were studied. The 3 m x 1.5 m spacing provided greater volumetric production and average annual increment in all evaluations, while the 3 m x 3 m spacing promoted an increase in basic wood density of 10% in relation to the smallest spacing and 6% in relation to the largest spacing. For energy production, no significant difference was identified between the spacing. Thus, spacing in medium proportions are more appropriate when considering the basic density of the wood, but, if the objective is volumetric production even with smaller diameters, smaller spacing is recommended.