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Little attention was given to the climatic signals in wood properties, such as microfibril angle (MFA) and tracheid radial diameter (TRD). In this article, year-to-year variation in MFA and TRD was measured by SilviScan-3 on dated Picea crassifolia trees growing at three altitudes in the northeastern Tibetan plateau. Climatic signals registered in MFA and TRD were analyzed using dendroclimatology methods. The annual variation of MFA and TRD was strongly linked to high-frequency climatic signals. Both MFA and TRD were negatively correlated with temperature and positively correlated with precipitation. The temperature had a similar influence on MFA and TRD at three different altitudes, while the influence of precipitation decreased with the increasing altitudes. MFA was negatively correlated with TRD, and this MFA-TRD internal relationship ( R) varied with calendar year. Temperature and precipitation had a strong influence on R. Temperature was positively correlated with R, and precipitation was negatively correlated with R. The influence of temperature was stronger than that of precipitation. The influence of temperature increased with the increase in altitudes, while the influence of precipitation decreased with the increasing altitudes. Results of this study revealed that the trees could change their internal characteristics to adapt to the changing climate. [ABSTRACT FROM AUTHOR]

A radial core from a Norway spruce ( Picea abies (L.) Karst.) estimated to be about 107 years old was cut from a board and was analyzed for density and microfibril angle (MFA). Furthermore, cell geometry, wall thickness and lignin distribution were analyzed on three selected growth rings in detail. Intra-ring differences in the density profiles are also true for cell wall thicknesses as well as radial and tangential lumen diameters. A higher MFA was found for earlywood with a slow decrease toward the latewood region. The lignin was found to remain rather constant throughout the growth rings, which suggests a constant chemical composition of the cell wall material within the growth ring. From the recorded datasets on a cellular level, it can be concluded that the main adaptation regarding structure-property relationships toward the optimization of water transport and mechanical stability is mainly achieved at the cell level. [ABSTRACT FROM AUTHOR]

This study presents three-point bending test results of Norway spruce clear wood specimens loaded on the radial-longitudinal plane in two different load cases. The tested samples were graded as resonance wood for instrument making and were characterised by narrow annual rings and relatively low density. The modulus of elasticity (MOE) and the corresponding modulus of rupture (MOR) are illustrated separately for the samples with straight grain and the group showing the specific growth pattern of indented rings ('hazel growth'). With the longitudinal wood anatomical direction parallel to span width, the fibre deviation caused by the indents reduces MOE and MOR values, whereas a 'reinforcing' effect of the indents could be observed for the load case with span width parallel to the radial direction. Both aspects lead to a reduction in anisotropy for hazel-growth Norway spruce (anisotropy MOE: indented rings 11.6, straight grain 14.7, anisotropy MOR: indented rings 6.9, straight grain 8.9), which partly explains the exceptional position of this growth pattern for the construction of high-class musical instruments with outstanding mechanical and acoustical performance. [ABSTRACT FROM AUTHOR]

Australia is recovering from a disastrous fire season that may prove to be the new normal as the planet continues to heat up. In Queensland, New South Wales and Victoria, more than 1 billion animals and 3500 homes were burned in 160,000 km SP 2 sp (approximately equal to the area of the state of California). This was followed by a huge dust storm and unseasonal heavy rain that caused extensive flooding and dropped large quantities of red mud over Victoria and New South Wales. [Extracted from the article]

The IAWS Executive Committee was invited to Moscow to participate in the celebrations of the 100th anniversary of the foundation of Mytishchi Branch of Bauman Moscow State Technical University hosted by IAWS Fellow and Director Professor Viktor Sanaev. Fellow Sanaev was awarded the IAWS Lecture at this symposium and presented "Interaction Of Wood With Protective-Decorative Materials". The next IAWS Plenary Meeting will be held in South Korea as a fitting start to the first term of the new IAWS President Yoon-Soo Kim who will take over from me on June 2, 2020. [Extracted from the article]

The article presents obituaries for several people including Ants Teder, David Barrett and Josef Schurz.

The article announces awards given to researchers at the International Academy of Wood Science (IAWS) Ph.D. Award including Michaela Zauner from ETH Zurich, Shengcheng Zhai from Kyoto University, and Salim Hiziroglu from Oklahoma State University.

The article presents newsbriefs related to the International Academy of Wood Science (IAWS) including the Distinguished Service Award to IAWS member Boris Ugolev, the meeting of IAWS to be held in Vietnam on May 10-16, 2015, and new members of the Academy including Barry Gardiner, and Meng Gong.

The article presents information on the International Academy of Wood Science (IAWS) Plenary Meeting 2014, "Eco-Efficient Resource Wood With Special Focus on Hardwoods," to be held in Sopron, Hungary, and Vienna, Austria, during September 14-18. It also presents information on newly elected members of the IAWS Executive Committee and Academy Board, including President Uwe Schmitt, Treasurer Howard Rosen, and Bulletin Editor Roberta Farrell.