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Mengyu Dong, Haibin Zhou, Xiaomei Jiang, Yun Lu, Weibin Wang and Yafang Yin

We examined fifty main structural components from fifteen historical wood buildings located in the northern, central, southern and south-eastern regions of Shanxi Province, China and dating from the Tang to the Qing Dynasty. Eleven timber-tree genera were identified: Cupressus, Larix, Malus, Picea, Pinus subg. Diploxylon, Populus, Quercus, Sophora, Sorbus, Ulmus and Zizyphus. Furthermore, wood specimens of Larix and Pinus subg. Diploxylon were determined to species level, viz. Larix gmelinii var. principis-rupprechtii and Pinus tabuliformis, according to their original geographical distribution in this region. Natural distribution of the wood species was apparently the leading criterion for timber selection since most identified genera are native to the areas surrounding the buildings investigated.

Peter Gasson, Caroline Cartwright and Claudia Luizon Dias Leme

Wood retains most of its anatomical characteristics when charred, but charring temperature determines the appearance of the resulting charcoal and this depends largely on the proportions and distribution of the constituent vessels, fibres and parenchyma, as well as moisture content. This study describes the structural changes in the charcoal of the wood of Croton sonderianus Muell. Arg. at two temperatures, 400 °C or 600 °C. This species is an important source of charcoal in the caatinga of the northeast part of Brazil. The samples were heated for ten minutes to reach treatment temperature, charred for two hours at either 400 °C or 600 °C and then left to cool to ambient temperature for 30 to 60 minutes. Our observations showed that most of the changes occurred when charcoal was produced at 600 °C, but the qualitative features necessary for identification were retained. At this temperature, cells lost their circular shape, became angular and occasionally amorphous, the middle lamella disappeared and the walls of adjacent cells coalesced, cell walls became thinner, and the prismatic crystals developed cracks and became porous. Our findings are compared with those for two previously studied Mimosa species which have an entirely different anatomy.

Ekaterina L. Kotina, Alexei A. Oskolski, Patricia M. Tilney and Ben-Erik Van Wyk

The wood and bark structure of Leucosidea sericea and two species of Cliffortia, the South African members of the tribe Sanguisorbeae (Rosaceae) are described. These two genera share few anatomical traits (the presence of schizo-rhexigenous intercellular spaces in the cortex, almost exclusively simple perforation plates, small alternate intervessel pits, etc.) with other Rosaceae. However, Leucosidea shows a distinct storied structure of the secondary phloem and wood as well as stratification of the secondary phloem, with conductive elements and nonsclerified crystalliferous axial parenchyma arranged into alternating bands. These conditions are recorded for the first time for the family Rosaceae. In contrast to Leucosidea, two species of Cliffortia show neither storied structure of secondary phloem and xylem, nor stratification of secondary phloem.

Isabel Carrillo, Sofía Valenzuela and Juan Pedro Elissetche

An evaluation of 100 Eucalyptus globulus and 100 E. nitens trees (six years old) was made using the Pilodyn micro-drilling tool as an indicator of wood density. Thirty E. globulus and thirty E. nitens trees with high, medium and low density were selected and sampled with an increment borer at breast height for anatomical analysis using fibre tester equipment and the Resistograph device to generate detailed information about fibre biometry and anatomical wood properties of both species for hybrid development. Eucalyptus globulus trees had a basic wood density average of 478 kg/m3, while E. nitens had a density of 490 kg/m3. Both micro-drilling tools showed significant correlation coefficients with basic wood density. Correlation coefficients between basic wood density and Pilodyn values were negative, being -0.53 (p = 0.01) and -0.68 (p < 0.001) for E. globulus and E. nitens, respectively. For both species a positive correlation was observed between basic density and Resistograph mean amplitude; the correlation coefficient was 0.84 (p < 0.001) for E. globulus, and 0.85 (p < 0.001) for E. nitens. Eucalyptus nitens trees had a higher density and amplitude average and smaller Pilodyn values than E. globulus trees, while the latter had higher coarseness, fibre length and diameter at breast height than E. nitens trees. However, E. nitens showed larger differences between features of earlywood and latewood in a growth ring than E. globulus trees.

Sherwin Carlquist and C. Matt Guilliams

The four species of Lennoaceae have strands of primary plus secondary xylem in a background of starch-rich parenchyma. These strands constitute a cylinder with large primary rays. The wood within these strands is markedly different from that of other families in the crown group of Boraginales such as Cordiaceae and Ehretiaceae, most of which are woody. Lennoaceae differ because they lack fibrous cells (libriform fibers), lack rays within the vascular strands, and have markedly elliptical vessel-to-vessel pits without vestures. Lennoaceae have secondary xylem with short, wide vessel elements with thick walls, horizontally elongate elliptical pits, simple perforation plates much narrower than the vessel lumen; variously uneven vessel wall thickenings; and axial parenchyma. The wood of Lennoaceae shows resemblances to unrelated succulents such as Kalanchoe (Crassulaceae) and Lithops (Aizoaceae). The vessel features also suggest adaptation to high water tensions as root parasites in desert areas, whereas the lack of imperforate tracheary elements may relate to support of the underground stem portions by sand or rock detritus. Habit and ecology are more important in the architecture of lennoaceous xylem than systematic affinities. The four species of Lennoaceae differ from each other in minor xylary features.

Pieter Baas, Steven R. Manchester, Elisabeth A. Wheeler and Rashmi Srivastava

Wood of Connaroxylon dimorphum (Connaraceae, Oxalidales) from the Deccan Intertrappean Beds of India (KPg Boundary 65–67 MY BP) is described. It is characterized by parenchyma-like fiber bands alternating with normal fibers, septate and nonseptate fibers, vessel-ray pits with strongly reduced borders, uniseriate rays of square and upright cells, and radial tubules in the center of ray cells that are arranged in a herringbone pattern. The overall wood anatomy strongly resembles Melastomataceae p. p., Lagerstroemia p. p. (Lythraceae) and Connarus (Connaraceae). However, the shared radial tubules of Connarus and the fossil strongly tilt the evidence of botanical affinities towards this genus. This would represent the second and by far the oldest fossil wood record of the Connaraceae, also considerably older than the earliest fossil records of the family’s other plant parts, and one of the oldest fossils of the order Oxalidales.

Carla J. Harper, Anne-Laure Decombeix, Edith L. Taylor, Thomas N. Taylor and Michael Krings

Silvia Rodrigues Machado, Carmen Regina Marcati, Ray F. Evert and Pieter Baas

Laurence R. Schimleck, Jorge Luis Monteiro de Matos and Charles Espey

Caesalpinia echinata Lam. (pernambuco or pau-brasil) is recognized as the premier raw material for manufacturing stringed instrument bows. Several studies have identified properties considered important in determining the suitability of pernambuco wood for bow manufacture including density, modulus of elasticity (MOE), and, possibly, microfibril angle (MFA). No research has been conducted on how these properties vary within individual trees; however, an understanding of how pernambuco wood properties vary within trees is important as it may assist in the identification of trees or provenances most suited for the establishment of plantations, aid in developing an understanding of management practices on wood property variation for plantation-grown pernambuco and also facilitate the identification of regions within trees that possess optimal properties for bow manufacture. Radial variation in density, MFA and MOE was examined using SilviScan for three radial strips representing differing levels of wood quality in terms of perceived suitability for making high-quality bows. The lowest quality sample showed considerable radial variation compared to the higher quality samples for all properties and it also had the lowest average density. It was not possible to identify a strong pith to bark trend for any of the wood properties examined.