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The main objective of this study was to assess the properties of Nothofagus alpina (raulí) wood from thinning that originates from two sites with intensive silviculture and one similar to a secondary growth forest, with different soil, climatic conditions and age. To achieve this, some mechanical, physical and chemical-crystalline properties were characterized; studying the differences from pith to bark and between the selected trees that were taken from the thinning of the three plantations. Among the studied plantation sites, there were statistical differences in equilibrium moisture content, density and modulus of elasticity. Furthermore, FT-IR was able to differentiate the chemical-crystalline compositions from pith to bark and between plantations, while the X-Ray diffraction showed differences in the crystallinity index. It was possible to differentiate between the sites with a more intense silvicultural intervention and the one with more variable growth conditions. [ABSTRACT FROM AUTHOR]

The main objective of this study was to assess the properties of Nothofagus alpina wood from thinning that originates from two sites with intensive silviculture and one similar to a secondary growth forest, with different soil, climatic conditions and age. To achieve this, some mechanical, physical and chemical-crystalline properties were characterized; studying the differences from pith to bark and between the selected trees that were taken from the thinning of the three plantations. Among the studied plantation sites, there were statistical differences in equilibrium moisture content, density and modulus of elasticity. Furthermore, FT-IR was able to differentiate the chemical-crystalline compositions from pith to bark and between plantations, while the X-Ray Diffraction showed differences in the crystallinity index. It was possible to differentiate between the sites with a more intense silvicultural intervention and the one with more variable growth conditions.

Cyclocarya paliurus is a highly valued and multiple function tree species. There has been increasing interest in planting and managing C. paliurus for timber production and medical use owing to loss of harvestable acreage. Seed from six provenances was collected from the main natural range of this species. Significant variation in growth and wood properties was measured among the six provenances at age 7 years. Provenance mean height and DBH varied significantly from 730-991 and 6.7-10.0 cm, whereas provenance means of wood basic density and crystallinity ranged from 463-554 kg m and 51.4-74.1 %, respectively. Mean provenance microfibril angle (MFA) at breast height ranged from 18.1° to 23.2°, while MFA at breast height varied from 11.0° to 34.5° among growth rings which showed a consistent pith-to-bark trend of declining angles. There was no significant relationship of growth rate with latitude or longitude of seed sources, however, provenances from low latitude and longitude grew faster at the trial site. Wood quality was significantly related to latitude of seed sources, showing a positive correlation for both wood basic density and wood crystallinity, but a highly negative association with MFA. Significant correlations between wood properties measured indicated that there exists a great opportunity to improve wood quality of C. paliurus through selection of juvenile trees with low MFA. [ABSTRACT FROM AUTHOR]