WOOD RESEARCH Volume 62, Number 3, 2017
Xu Bin, Yang Zhao Ying, Liu Shuai, and Chao Juan

Comparative identification and analysis amongst suspected gold Phoebe sp. buried wood

Buried wood samples of gold “Phoebe sp.” (Samples #1, #2 and #3) were identified based on their microstructures and on the comparison of their characteristics with relevant specimen types. The result showed all the samples belong to the family Lauraceae. Samples #1 and #3 of the Machilus Nees were identified as Phoebe sheareri and P. zhennan, respectively, they are also known as “Nanmu”. Meanwhile #2 was also referred to as Machilus Nees, but named as “Nanmu with black bark”. Significant differences in anatomical characteristics were determined amongst the three samples; thus, they could not be classified as gold Phoebe sp. Moreover, the practical densities of the samples showed no marked increase relative to the species in literature. Microscopy also exhibited no rare mineral enrichment in the cell lumen or the intercellular space. Results of this study indicated that the three samples do not belong to the category of buried wood or ebony.

WOOD RESEARCH Volume 63, Number 5, 2018
Vladimir Ilyich Fedyukov, Mikhail Vladimirovich Boyarsky, Ekaterina Yuryevna Saldaeva, Maria Sergeyevna Chernova, and Vasiliy Yuryevich Chernov

Dependence of spruce wood resonance properties on its chemical composition

Nowadays there are no reasoned scientific data on inter relation of resonant properties of spruce-tree wood and its chemical composition. Thus the purpose of the study was to reveal the features of sonorous spruce in view of the content of basic organic substances in their timber. 20 model trees at the age of 180-190 years were selected as material for studies in taiga woods in the north of Kirov region of Russia. Special 0.5 m long blocks were made from each model tree at height of 1.3 m. Standard 20×20×300 mm samples were made from those blocks. Test samples were kept at room dry conditions for 2 years. After that dendro acoustic studies were carried out on them to define acoustic constant in different directions with respect to timber fibers. Further the percentage of cellulose, lignin, extractives and ashes in them was defined applying standard techniques. As a whole the chemical composition of spruce tree resonant wood lies approximately within the same limits as in common wood of the breed given. However significant influence of cellulose on a longitudinal acoustic constant and lignin on a radial constant is revealed. Joint influence of lignin and cellulose on a tangential constant is found out, the influence of lignin in the latter case being dominant. Continuation of fundamental research in this field has great cognitive value for revealing the nature of unique acoustic properties formation in sonorous spruce wood. Such studies acquire special topicality when dealing with outstanding violins as well as the wood kept for many decades in old buildings subject to demolition.

WOOD RESEARCH Volume 65, Number 1, 2020
Marcin Jakubowski, Arkadiusz Tomczak, Tomasz Jelonek, and Witold Grzywiński

Variations of wood properties of birch (Betula pendula Roth) from a 23-year old seed orchard

This work presents the results of selected wood properties in birch trees grown on a provenance experiment plot established as a seed orchard. The study concerned: basic density, oven-dry density and compression strength along the grain at a moisture content of 0% and at moisture content above fiber saturation point. Analyses were performed on 971 wood samples collected from 28 trees at the level of breast height. It was found high variability for diameter of breast height (22%) and relatively low for basic density (9%) and oven-dry density (11%). Average basic density was 446.5 kg.m-3 and average oven-dry density was 537.9 kg.m-3. The compression strength at 0% moisture content was four times higher (65 MPa) than the strength at moisture content above the fiber saturation point (16.6 MPa). Most of clones had similar properties within the limits of statistical errors, but a few clones exhibited statistically significant low value.