Understanding the macroscopic structure of wood and its formation is essential to identifying wood and evaluating its properties and quality. Depending on genetic background, environmental conditions, and tree developmental stage, the macroscopic structure of wood can vary greatly and produce specific macroscopic signatures. Here, a comprehensive outline of the wood’s macroscopic structure and the features that can be used to identify wood by macroscopic examination is presented. The planes of observations are first depicted, and the fundamental differences between softwoods and hardwoods are outlined. Then, all the different cell characteristics, arrangements, and distributions that can be macroscopically observed are illustrated with their influence on wood figure and texture and non-anatomical features.

Since the dawn of humanity, wood has been the material of choice for crafting musical instruments due to its favorable acoustic properties, workability, and aesthetic value. Acoustic guitars are among the most widespread musical instruments worldwide, and today are industrially manufactured by large companies with global markets. This study investigates the use of wood in modern acoustic guitars, with a focus on wood species and sustainability. The websites of the 14 most relevant manufacturers on a global scale were analyzed collecting data on 874 guitars and 4506 components. The purpose of the research is to provide a novel overview of the variety and relevance of woods employed in the sector, of the most common environmental issues associated with their use, and of the strategies adopted by companies to deal with sustainability concerns and to communicate their environmental commitment to the public.

Land-use legacy on forest dynamics at both stand and landscape scale can last for centuries, affecting forest structure and species composition. We aimed to disentangle the history of the charcoal production legacies that historically shaped Mont Avic Natural Park (Aosta Valley, Italy) forests by integrating LiDAR, GIS, anthracological, and field data at the landscape scale. We adopted different geostatistical tools to relate geographic layers from various data sources. The overexploitation due to intensive charcoal production to fuel mining activities shaped the current forests by homogenising their structure and species composition into dense and young stands with a reduction in late seral species such as Norway spruce (Picea abies) and an increase in pioneer species such as Mountain pine (Pinus uncinata). The multidisciplinary and multi-scale framework adopted in this study stresses the role of historical landscape ecology in evaluating ecosystem resilience to past anthropogenic disturbances.

Species identification is a crucial step in the study of wooden artefacts, but sampling is frequently impossible. The objective of this study is to evaluate the efficacy of reflected light microscopy, including the use of polarising and narrow-band blue filters, as a non-invasive identification tool. Different surfacing and finishing techniques copying historical manufacturing methods were applied to selected species. The visibility of anatomical features was evaluated on the basis of a four level scale. Two indexes were created: an Identifiable Anatomical Features index (IAF) to evaluate the effect of treatments on the complex of microstructural characters, and a Feature Recognition Index (FRI) to estimate the susceptibility of each anatomical feature towards different treatments. Surfacing affected the visibility of anatomical features to different degrees of severity depending both on the technique used and on the species. The visibility could be partially improved or decreased by the presence of finishes, depending on their transparency. Each anatomical feature showed different susceptibilities towards treatments. Both polarising and narrow-band blue filters considerably increased visibility of several anatomical features. Possibilities to recognise individual character states were encouraging, except when obscured by low transparency finishes. Much diagnostic anatomical information can be obtained by the use of non-invasive, reflected light microscopy, although the step from feature recognition to species identification may still require further analysis.

Field deployable computer vision wood identification systems can play a key role in combating illegal logging in the real world. This work used 764 xylarium specimens from 84 taxa to develop an image data set to train a classifier to identify 14 commercial Colombian timbers. We imaged specimens from various xylaria outside Colombia, trained and evaluated an initial identification model, then collected additional images from a Colombian xylarium (BOFw), and incorporated those images to refine and produce a final model. The specimen classification accuracy of this final model was ~ 97%, demonstrating that including local specimens can augment the accuracy and reliability of the XyloTron system. Our study demonstrates the first deployable computer vision model for wood identification in Colombia, developed on a timescale of months rather than years by leveraging international cooperation. We conclude that field testing and advanced forensic and machine learning training are the next logical steps.

The bonding quality is a key property for wood-based composites. Determination of the bonding quality of sandwich panels with veneer faces and <50 mm thick cork core is not covered either by the EN 314-1, which refers to plywood, nor by its Annex B, which refers to insulating cores with a thickness of at least 50 mm. This technical note assesses the possibility of using the prescriptions of Annex B of EN 314-1 to test the bonding quality (shear strength) of the concerned panels. For this purpose, sandwich panels were realized by bonding fromager (Ceiba pentandra) veneers to a 5 mm thick core, and their bonding quality was tested. Two types of panels were realized, based on the adhesive used (glue spread 340 g/m² for double glue lines): urea–formaldehyde (UF) and urea–melamine–formaldehyde (UMF); the panels were pressed at 103 °C for 8 min at a nominal pressure of 0.4 MPa. Pre-treatments were dry-conditioned at 20 °C/65% relative humidity until attainment of the equilibrium moisture content, and immersed in water: cold water for UF panels (5.1.1 of EN 314-2) and boiling water for UMF panels (5.1.2 of EN 314-2). The effect of pre-treatment was statistically significant, with shear resistance reductions of 56% and 43% in UF and UMF panels, respectively. Based on this first investigation (2 panels × 10 specimens per panel = 40 specimens), the test method can be considered suitable for providing reliable results. This study constitutes a useful reference to test the bonding quality of sandwich panels with veneer faces and thin cork cores.