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The manufacturing process of wood agglomerate integrates distinct unit that transforms wood raw material into wood agglomerate. The yield of wood agglomerate produced is influenced by the density and the quality of the initial raw material. This work has compared two distinct methodologies aimed at defining the yield of the process through an indirect measurement at the precursor material. Samples (logs of differentiated sizes) were collected immediately at the industry entrance and several parameters were measured. The logs basic density and the moisture content was annotated, through analysis of the corresponding dry and wet mass. Log bark percentage has estimated also at the level of dry and wet basis. These parameters were used to determine the wood volume from different provenance and species in the beginning of the industrial process. The results indicated that wasn’t a great difference between the two different methods to determine the wood basic density and the wood volume in m3. Principal components analysis was used to investigate the differences between different provenances and different species for the wood basic density, and we conclude there is a great variability in wood basic density for the hardwood species than the observed for the softwood and there isn’t a great variability between different provenances. We study too the difference off wood moisture that could be occurring before the evaluation of wood basic density.

In this paper we analyze the transversal variation of Acacia melanoxylon R. Br. wood porosity, using five trees with 40cm dbh collected in the Ponte de Lima region, in northwestern Portugal. Variation of porosity, vessel area, width and density were used to evaluate tree vessel variation, in order to relate it with other wood properties. Each value of these variables represents a mean of 60 vessels measurement. We collected five wood disks at the bottom, 5, 15, 35 and 65% of total height, and commercial top of those five trees, in order to acquire three radial cores at 10, 50 and 90% near the pith, and in north and south directions. We found great variability along the tree concerning the axial and radial positions. Porosity is higher near the bottom and lower at the top; vessel number varies inversely. Vessels width and density are similar at the different height levels. Radial variation show that porosity, vessel area and vessel width all increase, and density decreases, with distance to the pith. Principal components analysis was used to investigate the differences in vessel characteristics and levels in the trees, as well as their interaction. This methodology allowed us to determine how close, or how independent, the study variables were. We conclude there is a group of vessel morphologic characteristics which depend strongly on each other – porosity and vessel area and vessel number are negatively correlated with the other. The variation between North and south direction is not significant, because the values are very similar and the trees don’t present a higher eccentricity.