Search Results (32)

China’s timber market is very complex and heterogeneous, and is experiencing the impact of the construction of national reserve forests and the downturn in the real estate sector. By setting up a partial equilibrium model which reflects the heterogeneity of China’s wood market, not only difference among domestic timber groups can be identified, but the dissimilarity of imported timber can also be differentiated from the aspects of species and sources. This model is capable of capturing the effects of macroeconomic conditions, forestry sector policies, and trade cost variations on China’s timber market structure. According to simulations of supply shocks, China’s large-diameter log capacity enhancement will have a noticeable crowding-out effect on imported timber, suggesting the diameter of logs is an important factor for market entities to make trade-offs between domestic and imported timber. Amidst both supply and demand shocks, the equilibrium quantity changes in China’s domestic small-diameter logs and imported timber are dominated by demand shocks, whereas the equilibrium quantity change in China’s domestic large-diameter logs is dominated by supply shocks; moreover, only domestic large-diameter logs realize quantity increase in double shocks; this improves China’s domestic timber supply structure, and is a good example of “opportunities in crisis” in the face of negative demand shocks. Full article

This study explores how integrating design processes into the native timber industry of southern Chile, specifically in the Araucanía and Los Ríos regions, can improve the value chain and promote sustainability. Chile’s native wood sector is constrained by fragmented value chains, underutilised small-diameter logs and limited market confidence. These challenges jeopardise forest sustainability and rural livelihoods, underscoring the imperative to find innovative solutions to reinvigorate the sector. A market gap analysis revealed critical limitations in the current industry, including low supply, limited demand, and weak technological development, especially in producing value-added wood products. The research identified over 417,000 hectares of second-growth roble (Nothofagus obliqua)-raulí (Nothofagus alpina)-coigüe (Nothofagus dombeyi) forests suitable for sustainable management. Interviews with woodworking SMEs showed that 66% already use native timber, yet 46% of the projected volume remains underutilised due to the prevalence of short and thin logs. In response to these challenges, the study developed innovative prototypes such as interior claddings and lattices made from smaller, underutilised logs. These designs were evaluated and validated for use in residential and public buildings, demonstrating their potential to meet new market demands while promoting resource efficiency. The results show that, whilst there is a clear need for better infrastructure, workforce training, and commercial planning to support product adoption, design-driven innovation offers a promising path forward enhancing the industry’s competitiveness. Demonstrating how design-led integration can transform under-used native timber into high-value products, simultaneously driving sustainable forest stewardship and local economic growth. Full article

The construction sector’s increasing eco-consciousness is driving the need for higher-performance wood-based engineered products from underutilized timber resources, such as small-diameter trees from hazardous fuel treatments of our forests. Strand-based products, including oriented strand board (OSB) and lumber (OSL), are widely used. However, hot-pressing during their manufacturing generates approximately 10% waste, which includes a substantial amount of resinated strands that are landfilled. The huge potential of using strand-based products has led to many studies and growing interest in strand-based three-dimensional sandwich panels that can be used as wall, floor, or roofing panels. As the market grows, understanding the recyclability of these resinated strands becomes crucial. This study investigates the feasibility of using re-resinated waste strands that were collected during lab-scale production of strand-based panels. Results demonstrate significant improvements in dimensional stability, mechanical properties, and fire resistance. Specifically, recycling increased internal bond strength, flexural strength, time to ignition, time to flameout, mass loss, and time to peak heat release rate by 107%, 44%, 58%, 35%, 51%, and 27%, respectively, and helped decrease water absorption and thickness swell by 51% and 58%, respectively. Full article

Enhancing the decay resistance of Populus tomentosa wood through environmentally friendly methods is crucial for improving its durability and market competitiveness. Lignified twigs (LT), typically unsuitable as timber due to their small diameter, are rich in lignin, which degrades during thermal induction to produce antifungal organic compounds. In this context, the objective of this study was to develop a lignified twig preservative (LTP) by thermal induction from the LT of Actinidia chinensis var. Jinyang. The antifungal activity of LTP under varying thermal conditions was analyzed, along with its chemical composition. Enzyme activity, cell membrane integrity, and respiratory metabolism in fungi treated with LTP were examined to elucidate antifungal mechanisms. Additionally, the decay resistance of LTP-treated wood was evaluated. Results revealed that LTP produced under N₂ at 220 °C exhibited robust antifungal activity against Trametes versicolor and Gloeophyllum trabeum, attributed to phenolic compounds such as syringaldehyde, syringone, vanillin, and vanillone. LTP inhibited fungal cellulases, hemicellulases, and ligninases by 30%–60%, disrupted cell membrane functionality, and suppressed respiratory metabolism. Poplar wood treated with LTP demonstrated significantly enhanced decay resistance (mass loss < 10%). This thermal-induced feedback pattern shows great potential for LT in wood preservation. Full article

The development of branches on the lower part of the trunk plays a decisive role in the early growth of trees and influences the wood quality of their most valuable sections. This study investigated the effects of planting density on the horizontal and vertical spatial distribution, branch morphology, and branch quantity characteristics of two elite clones of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), Yang 061 and Yang 020. The results revealed the following distinct responses between the two clones: Yang 061 exhibited significant reductions in branch base diameter and length under a higher planting density, alongside an increased frequency of small branches (<15 mm), but there was no significant effect on branch angles. In contrast, Yang 020 was primarily influenced by genetic factors, with planting density exerting minimal impact. This clone optimized resource allocation by promoting the mortality of lower branches through angle adjustments, resulting in negligible changes to branch development across different planting densities. Pronounced differences in vertical and horizontal branch distributions were observed in areas with significant light disparities, such as the middle crown and northeast direction, for both clones, with increased planting density exacerbating these differences. In conclusion, increasing the planting density of Yang 061 from 2500 to 3333 trees·ha⁻¹ can effectively reduce its branch size; whereas, increasing the planting density of Yang 020 from 3000 to 5100 trees·ha⁻¹ can slightly decrease its branch size without affecting its early rapid growth, thereby achieving a synergistic improvement in both timber yield and quality. These findings highlight the importance of interactions between genetic traits and planting density in shaping branch development and spatial distribution patterns, providing insights to optimize planting density for improving the productivity and wood quality of Cunninghamia lanceolata plantations. Full article

We evaluated the long-term impacts of various forest management practices on the structure and biodiversity of Estonian hemiboreal forests, a unique ecological transition zone between temperate and boreal forests, found primarily in regions with cold winters and moderately warm summers, such as the northern parts of Europe, Asia, and North America. The study examined 150 plots across stands of different ages (65–177 years), including commercial forests and Natura 2000 habitat 9010* “Western Taiga”. These plots varied in stand origin—multi-aged (trees of varying ages) versus even-aged (uniform tree ages), management history—historical (practices before the 1990s) and recent (post-1990s practices), and conservation status—protected forests (e.g., Natura 2000 areas) and commercial forests focused on timber production. Data on forest structure, including canopy tree diameters, deadwood volumes, and species richness, were collected alongside detailed field surveys of vascular plants and bryophytes. Management histories were assessed using historical maps and records. Statistical analyses, including General Linear Mixed Models (GLMMs), Multi-Response Permutation Procedures (MRPP), and Indicator Species Analysis (ISA), were used to evaluate the effects of origin, management history, and conservation status on forest structure and species composition. Results indicated that multi-aged origin forests had significantly higher canopy tree diameters and deadwood volumes compared to even-aged origin stands, highlighting the benefits of varied-age management for structural diversity. Historically managed forests showed increased tree species richness, but lower deadwood volumes, suggesting a biodiversity–structure trade-off. Recent management, however, negatively impacted both deadwood volume and understory diversity, reflecting short-term forestry consequences. Protected areas exhibited higher deadwood volumes and bryophyte richness compared to commercial forests, indicating a small yet persistent effect of conservation strategies in sustaining forest complexity and biodiversity. Indicator species analysis identified specific vascular plants and bryophytes as markers of long-term management impacts. These findings highlight the ecological significance of integrating historical legacies and conservation priorities into modern management to support forest resilience and biodiversity. Full article

Oak is one of the most economically important hardwood tree species in Europe, and its prevalence will increase due to progressing global climate change, according to predictive models. With the increasing demand for timber and with the need for a balance between carbon emissions and sequestration, it is essential to address the afforestation of agricultural land. Therefore, this research aimed to investigate the physico-mechanical properties and anatomical structure of pendulate oak (Quercus robur L.) wood—specifically focusing on the trunk’s cross-section—in post-agricultural areas compared with the forest land in the western part of Poland. Wood density, bending strength, modulus of elasticity, and other parameters were analyzed from 1626 wood samples. The analysis of physico-mechanical properties reveals that, historically, agricultural land use has an almost negligible impact on wood quality. Despite significant differences in small vessel diameter and fiber length favoring trees from post-agricultural land, the physico-mechanical properties remain consistent. Large vessel measurements show comparable diameter and length in both land types. These findings suggest that post-agricultural land can serve as an effective alternative for high-quality pendulate oak wood production for industrial purposes. However, wood from post-agricultural land may exhibit a decrease in modulus of rupture by over 30% and potentially lower density above the trunk’s halfway point. This observation hints at the fact that oak trees in post-agricultural areas could be cultivated in shorter rotation periods compared to forest land. Full article

Tropical forest management has a potential role in forest conservation if it is sustainable. This study of a forest under management in Bolivian Amazonia strongly suggests that the management project is not sustainable and that no potential changes in management would be likely to make it so. In a 216.41 ha harvested area, 278 commercial trees from 10 families, 15 genera, and 15 species were measured. The density of commercial species with diameter at breast height (DBH) ≥ 50 cm was 1.28 trees ha⁻¹, and the harvestable commercial volume was 12.40 m³ ha⁻¹. Due to market restrictions, the actual amounts harvested were much lower: 96 trees were harvested with commercial boles totaling 2.7 m³ ha⁻¹. Of the total impact on biomass and carbon (above- and belowground), the logs removed from the area represented only 13.4%, while 86.6% was from losses in the forest as follows: 14.5% from the stumps, crowns, and roots of harvested trees (DBH ≥ 50 cm) plus 72.1% from the trees (DBH ≥ 10 cm) in the forest lost to roads, log landings, and skid tracks and the gap openings caused by felling the harvested trees. The estimated expenses exceeded the gross revenue of the management company (USD 519.15 ha⁻¹), a fact confirmed by the company’s subsequent bankruptcy. The project’s low harvest intensity reduces the environmental impact per hectare but increases the impact per cubic meter of wood harvested because producing a given volume of wood requires disturbing a larger area and because more kilometers of access roads and skid tracks have to be installed to extract a given volume of wood. Because many costs are fixed regardless of harvest intensity, small harvest volume can render such projects financially unfeasible, increasing the likelihood that they will be abandoned and not provide long-term “sustainable” forest protection. However, this does not mean that higher harvest intensity results in sustainability, as other constraints apply to high-intensity projects. We conclude that conservation alternatives to maintain the forest would be more beneficial than management for timber. Full article

The evolution toward small-diameter and fast-growing plantation timbers such as the Pinus elliotti var. elliottii (Engelm) × Pinus caribaea var. hondurensis (Sénéclauze) (PEE×PCH) hybrids around the world is producing large volumes of core wood that are falling short of structural sawn timber grading requirements. Engineered timber products such as cross-laminated timber (CLT) and glue-laminated (glulam) offer potential solutions to value-adding this resource, but the bond performance of this feedstock and the extent to which current standards and guides address its common characteristics for bond performance need to be understood. This study investigated the bond quality and performance of clear defect-free, low stiffness out-of-grade PEE×PCH and evaluated this performance using the pass/fail criteria of the CLT bond performance requirements of three national CLT standards. 5-layer CLT delamination samples and shear block test samples were glued using one-component polyurethane (PUR). This process was repeated for common occurring characteristics in this resource of resin, knots, and pith to understand their impact and inform an evaluation on the need to restrict their inclusion. Clear samples had an average glue line delamination of 2.9% and an average glue line wood failure of 96.7%. Resin achieved 9.3% and 92.6%, respectively. While knots had the lowest performance at 24.4% and 77.4%, respectively. When pith was at or adjacent to the glue line, wood failure occurred through the pith and its immediate surrounding fiber. Shear strength and wood failure tests were carried out on glulam and CLT-oriented samples. CLT knot samples were tested in two load orientations. Glulam-oriented samples in clear, resin, pith, and knots achieved an average shear strength of 8.5 MPa, 8.2 MPa, 7.9 MPa, and 8.2 MPa, respectively, and wood failure of 86%, 85%, 90%, and 69%, respectively. CLT-oriented samples in clear and resin both achieved average shear strengths of 4.0 MPa; 0°-loaded and 90°-loaded pith samples achieved 3.6 MPa and 2.4 MPa, while 0°-loaded and 90°-loaded knot samples achieved 4.2 MPa and 4.7 MPa respectively. Average wood failures were 90%, 89%, 96%, 96%, 83%, and 51%, respectively. PRG320 was found to be the most restrictive standard. Resin, knots, and pith were not addressed in the evaluation of delamination or shear strength in any standard, and PRG320 was the only standard to restrict these characteristics over and above structural grading rules. The amount and type of characteristics present vary considerably in structurally graded wood, and even more so for this out-of-grade resource. It was determined that the negative impact that resin, knots, and pith have on bond quality and bond performance calls for some restriction of their inclusion in order to achieve the author’s interpretation of the intended bond performance requirements of the CLT standards, which currently do not address these characteristics well or at all. A proposed modification to the PRG320 effective bond area was presented as a proactive solution. Full article

The growth performance and technological quality of roundwood from a Paulownia elongata x fortunei hybrid (BIO 125 clone) was assessed in three plantations in Northern Italy. Dendrometric features (diameter at several heights, volume, and growth rate) and defects for industrial use were assessed on 20 standing trees and four logs per plantation. Compared to previously published literature, Paulownia trees have shown a high growth rate during the first three years after coppicing. Growth rate sharply decreased starting from the fourth year, suggesting an increased competition between trees and the need for greater planting spacing. At the end of the first year of growth, trees were pruned up to a height of 5 m, allowing the production of defect-free and high-quality roundwood. Log features were assessed according to European standards EN-1309-2:2006 and EN 1309-3:2018 and then compared with the EN 1316-2:2012 standard for poplar roundwood quality. Paulownia wood has shown to be of excellent quality, ranking in the best class (Po-A) for all parameters except diameter. A larger diameter could be easily obtained with longer growth cycles or greater planting spacing. A relevant problem for the industrial exploitation of Paulownia small-diameter logs would be the large empty pith that could drastically reduce timber yields. Full article

The increased demand for non-timber forest products (NTFPs) has led to the over-exploitation and disordered utilization of wild NTFP resources. Thus, it is important to determine how to sustainably utilize and cultivate NTFPs. Stubble and root cutting are two important methods for artificial cultivation, but little is known about their effects on the artificial cultivation of NTFP species with strong sprouting ability. Aralia elata is an important understory economic plant with high medicinal and edible values, and its wild resources are decreasing rapidly due to increasing demand. Therefore, A. elata, with its strong sprouting ability, was taken as an example to explore the effects of stubble (plant size × stubble height) and root cutting (root-cutting distance × root-cutting ratio) on its growth and sprouting ability for three years. The results showed that both stubble and root-cutting treatments could effectively facilitate the root sprouting ability of A. elata. The short stubble height treatment (6–15 cm) was the optimum stubble method for large A. elata (the mean height and basal diameter of plants were 256.65 cm and 4 cm, respectively). For small A. elata (plant basal diameter ranged from 1.5 cm to 3.4 cm), the optimal root-cutting method was 100% root-cutting ratio at a root-cutting distance of 0.25 m. However, the effects of stubble and root cutting on the growth and sprouting ability of A. elata were time-dependent, and repetitive treatment might be applied at an interval of two years to maintain its continuous growth and sprouting. Full article

Wood and charcoal were key sources of energy during early industrialization in Europe (18th century), preceding the large-scale exploitation of fossil coal. Past timber harvesting implied land transformation and woodland resources management. Therefore, relict charcoal kilns and historical documents of forest management are important sources of information about past woodland composition and structure. However, ancient charcoal kilns are poorly documented in temperate woodlands in the lowlands of western Europe, especially combined with historical written sources. In this study, charcoal production was investigated in an area in NE France, by combining charcoal and historical sources analysis, along with innovative dating methodologies. Thus, by using both radiocarbon and optically-stimulated luminescence dating, we showed that the activity lasted until recent times (19th–early 20th centuries) and Carpinus was the dominant taxon in charcoal assemblage. Moreover, kiln attributes seemed to be independent of topographical variables. Woodlands in this area were subject to a coppice-with-standards management, where small diameter wood was preferred to produce charcoal and large diameter stems, mainly Quercus and Fagus, were traded as timber. The dominance of Carpinus is rather uncommon in charcoal studies but supports the importance of Carpinus as fuelwood since the Middle Ages, as confirmed by many written sources. Full article

The purpose of this study was to develop high-performance wood strand panels for automotive application using resin transfer and compression resin transfer molding technologies. Wood strand preforms bonded with 1%, 5%, and 20% by weight low-density polyethylene and 1% by weight high-density polyethylene were impregnated with resin during the molding process and compared. The results showed that 1% low-density polyethylene is sufficient to bind wood strands into a stable preform for handling and processing. Permeability measurements using a volumetric interpretation of Darcy’s law accounted for resin flow through the thickness of the preform. When compared with previously published data on other natural fiber composites, resin transfer molded wood strand composites generally exhibited superior mechanical properties and significantly greater dimensional stability when exposed to moisture. Full article

Understanding tree species autecology and population structure supports effective conservation actions. Of particular importance are multipurpose trees that provide non-timber forest products (NTFPs). We assessed the population structures and morphologies of two species of NTFP trees in the genus Mimusops across bioclimatic zones in Benin by sampling 288 plots within 11 forests. Structural characteristics were compared between species, forests and zones. Correlations were also observed between Mimusops tree regeneration density, tree features and ecological characteristics. The density of trees ≥5 cm and of regeneration and mean tree height were higher for M. andongensis (within more protected forest) than M. kummel (in forests with access to people), while the highest mean diameter was observed for M. kummel. Tree and regeneration densities and mean height were greatest in the humid zone of Benin, whilst the largest mean diameter was obtained in the sub-humid zone. The results showed significant correlations between regeneration density and soil properties for M. andongensis but not for M. kummel. The correlations between tree morphology and soil characteristics were weak for both species. Ecological characteristics, along with the species’ functional traits and pressures, are important factors related to the observed differences between the species. All diameter classes were represented, and the population seemed more stable in the more protected forest relative to other forests. Mimusops trees with a diameter of 5–15 cm represented more than 30% of this species in most forests; this suggests, for M. kummel, whose trees flower when quite small (≥6 cm dbh), that there are sufficient reproductive trees. Thus, as a long-lived species, its populations could be maintained even with low/episodic recruitment. However, we found no regeneration in many forests and climate change could threaten populations. Therefore, it is important to investigate regeneration growth and dynamics, seed production and germination of the species in relation to the biophysical conditions and disturbances experienced by Mimusops stands. Full article

The United Nation’s Decade on Ecosystem Restoration 2021–2030 aims to halt ecosystem degradation to achieve Sustainable Development Goals (SDGs) by 2030. In Malaysia, the concept of sustainable forest management (SFM) has been practiced since 1901. In this study, we evaluated the genetic diversity of the native dipterocarp timber tree Shorea acuminata in a rehabilitated area at Kenaboi Forest Reserve (Kenaboi FR). The rehabilitated area was formerly a degraded forest managed with the taungya restoration system for 50 years. All trees with diameter at breast height (DBH) of 5 cm and over were measured, tagged and identified in a one-hectare study plot. A total of 132 inner bark samples were collected for DNA extraction. Four SSR markers (Sle280, Sle392, Sle475 and Sle566) and two EST-SSR markers (SleE07 and SleE16) were used to analyse 95 good-quality DNA samples. Genetic diversity parameters including maternal contribution were determined for 75 samples. The genetic diversity of big trees (H_e = 0.656 ± 0.19) and small trees (H_e = 0.652 ± 0.17) were high and both were in genetic equilibrium, with F_is values of the big trees being 0.035 and small trees being 0.164. Clustering analysis based on Jaccard’s similarity values (at 95% confidence level) confirmed that big trees in the Kenaboi FR rehabilitated area had originated from genetically diverse seed trees of the Sungai Menyala Forest Reserve which were used as the planting stock for the taungya restoration system. Maternal contribution showed that the allele contribution of the small trees came from the planted S. acuminata trees within the study area. The high genetic diversity of small trees in this study provides strong evidence that the existing big trees would be suitable for a genetically diverse seed collection to rehabilitate other degraded forests. Sustainable forest management must emphasise genetic diversity in order to ensure the resilience of rehabilitated forest ecosystems. Full article