Abstract To promote solid wood production, the diameter at breast height, height, stress-wave velocity, surface-released strain, basic density and compressive strength parallel to the grain were measured for 10 half-sib families of 12-year-old Eucalyptus camaldulensis Dehnh. trees growing in Thailand. Based on the results, growth rates, correlations among measured properties, radial and among-family variations of wood properties, and their repeatability were evaluated. Diameter at breast height, height, and wood volume were exponentially increased at initial stage, and then gradually increased toward to 12 years after planting. The maximum current annual increment and mean annual increment in wood volume showed at age of 8 and 11years old, suggesting that rotation period for optimum productivity may be ranged from 8 to 11 years old. Wood with stable properties was found greater than 6 cm from the pith. These results indicate that 12-year-old E. camaldulensis trees had already reached the maturation stage. No significant correlations were found between growth characteristics and wood properties. Significant variances in the height, stress-wave velocity, and basic density were found among the 10 families. The F-values and repeatability of the wood properties in the outer wood were higher than those in the inner wood. These results indicate that the properties of the outer wood are closely related to genetic factors. Thus, to obtain superior E. camaldulensis trees for solid wood production, the family selection should be conducted using the outer wood of aged trees.

中文翻译：

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泰国桉树半同胞家族实木生产生长特性和木材特性的可重复性

摘要 为促进实木生产，对10个12年生桉树半同胞科的胸径、高度、应力波速度、表面释放应变、基本密度和平行于纹理的抗压强度进行了测量。德恩。生长在泰国的树木。根据结果​​，评估了生长速率、测量特性之间的相关性、木材特性的径向和家族间变化及其可重复性。胸径、高、材体积在初期呈指数增加，到种植后12年逐渐增加。当前最大的木材量年增量和平均年增量出现在 8 岁和 11 岁，表明最佳生产力的轮作期可能在 8 到 11 岁之间。在距木髓 6 cm 以上的地方发现了具有稳定特性的木材。这些结果表明，12 年生的 E. camaldulensis 树已经达到成熟阶段。生长特性和木材特性之间没有发现显着的相关性。在 10 个科中发现高度、应力波速度和基本密度的显着差异。外层木材中木材特性的 F 值和可重复性高于内层木材。这些结果表明外层木材的特性与遗传因素密切相关。因此，要获得用于生产实木的优良E. camaldulensis 树木，应使用老树的外材进行科系选择。camaldulensis 树已经到了成熟阶段。生长特性和木材特性之间没有发现显着的相关性。在 10 个科中发现高度、应力波速度和基本密度的显着差异。外层木材中木材特性的 F 值和可重复性高于内层木材。这些结果表明外层木材的特性与遗传因素密切相关。因此，要获得用于生产实木的优良E. camaldulensis 树木，应使用老树的外材进行科系选择。camaldulensis 树已经到了成熟阶段。生长特性和木材特性之间没有发现显着的相关性。在 10 个科中发现高度、应力波速度和基本密度的显着差异。外层木材中木材特性的 F 值和可重复性高于内层木材。这些结果表明外层木材的特性与遗传因素密切相关。因此，要获得用于生产实木的优良E. camaldulensis 树木，应使用老树的外材进行科系选择。在10个科中发现了基本密度。外层木材中木材特性的 F 值和可重复性高于内层木材。这些结果表明外层木材的特性与遗传因素密切相关。因此，要获得用于生产实木的优良E. camaldulensis 树木，应使用老树的外材进行科系选择。在10个科中发现了基本密度。外层木材中木材特性的 F 值和可重复性高于内层木材。这些结果表明外层木材的特性与遗传因素密切相关。因此，要获得用于生产实木的优良E. camaldulensis 树木，应使用老树的外材进行科系选择。