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Accuracy, repeatability and time consumption of selected digital measurement methods of roundwood stacks
Wood density and annual ring width of pedunculate oak from stands grown on former agricultural land
The main aim of this study was to determine differences in basic density and average annual ring width of pendulate oak wood collected from trees grown on former agricultural land and on forestland, using a dimensional method. The experiment was carried out in thewestern part of Poland, near to Poznan, which is in the central part of the European range of pedunculate oak. In our study the average basic density was 0.528 g.cm-3, and the value for former agricultural land was lower by 0.026 g.cm-3 than that for forest land. Differences in basic density values between these two land types were statistically significant. The average annual ring width in samples collected from forest land in our study was 2.48 mm, samples from former agricultural land were characterized by wider average annual rings. The results suggest that there are significant differences in quality of wood from former agricultural land and from forest. However, from view of wood quality and applications the difference is not important.
The Wood Density of Pure and Mixed Norway Spruce, Scots Pine, and Silver Birch Stands in Lithuania Using IML Resi
The transition from pure to mixed-species forest stands is increasingly promoted to enhance ecosystem stability and multifunctionality. The growth conditions may influence the physical and mechanical properties of wood. This study evaluated wood density in pure and mixed stands of silver birch, Norway spruce, and Scots pine in Lithuania and analyzed its relationships with tree allometric parameters. Nine study plots representing pure (100%) and mixed (70/30%) stands were established under comparable site conditions. Wood density at breast height was assessed using resistance drilling (IML Resi PD500), and the increment core samples were analyzed with the LIGNOSTATION™ system. The mean values of wood density for silver birch differed by 11%, depending on the wood density determination method used. Differences between pure and mixed stands were insignificant and generally did not exceed 6%–10%. No consistent trend that was attributable to species mixing was identified. The combined data from pure and mixed stands indicate that the mean wood density, converted from microdrilling measurements, was highest in silver birch (546 kg m−3 ± 1.87 kg m−3), followed by Scots pine (476 kg m−3 ± 1.85 kg m−3) and Norway spruce (437 kg m−3 ± 1.66 kg m−3). Resistance drilling showed a moderate relationship with the core samples’ wood density (R2 = 0.59), supporting its suitability as a semi-nondestructive method. Diameter at breast height was the only tree parameter that was consistently significant across all predictive models. The combined model for all species explained up to 43% of wood density variation, while species-specific models had lower explanatory power. Overall, the results indicate that species mixing has a limited effect on wood density under the studied conditions and is unlikely to substantially alter wood quality in terms of wood density.
The Potential of Non-Native Pines for Timber Production—A Case Study from Afforested Post-Mining Sites
Scots pine (Pinus sylvestris L.) represents one of the most important commercial coniferous tree species, providing valuable timber. Due to climate change, it is experiencing serious problems in some areas, therefore, finding a suitable substitute for its wood is currently a challenge. In this study, we compared the wood quality of three different non-native pine species and Scots pine growing at the same site to ensure identical growing conditions. Black pine (Pinus nigra J. F. Arnold), a pine species native to Southern Europe, lodgepole pine (Pinus contorta Douglas ex Loudon), and ponderosa pine (Pinus ponderosa Douglas ex C. Lawson) native to North America were compared to Scots pine for selected quantitative (productivity) and qualitative (physical and mechanical) properties. Significant differences between pine species were found in all quantitative dendrometric parameters, except average diameter at breast height. The stand volume ranged from 157 m3 ha−1 for lodgepole pine to 356 m3 ha−1 for Scots pine. For qualitative characteristics, wood density, shrinkage, and compressive strength were used to find differences among species in choosing the best alternative. The highest wood density was obtained for Scots pine (458 kg m−3), followed by black pine with 441 kg m−3. The density of the remaining pine species was significantly lower. Scots pine also exceeded the tested species in compressive strength (44.2 MPa). Lodgepole pine achieved the second highest value (39.3 MPa) but was statistically similar to black pine (36.5 MPa). The tested pine species exhibited similar values in shrinkage, which were statistically insignificant, ranging from 14.3% for lodgepole pine to 15.1% for Scots pine. Based on applications and preferred characteristics, black pine or lodgepole pine could serve as the Scots pine substitute in some areas. And vice versa, ponderosa pine did not attain the Scots pine wood quality.
Moisture content of fresh Scots pine wood in areas near damage caused by harvester head feed rollers
By damaging bark, mechanized harvesting deprives wood of its natural mechanical barrier. This study concerns the effect of this damage on the changes in moisture content that occur near the damaged areas of Scots pine (Pinus sylvestris L.). This study was carried out using 45 randomly selected 11 m long logged pine stems. Additionally, the effect of bark thickness on the depth of damage was measured. To determine the influence of the location of the damage and bark thickness on the wood moisture near the damaged region, wood samples were collected from two sections. The first was located one meter above the log’s base, while the second was located one meter from the end of the log. Two increment cores were taken by a Pressler borer in each section: one from the damaged wood zone and the second from the undamaged wood zone. The average bark thickness one meter from the base of the log was 11.2 mm, which decreased to 1.8 mm in the samples taken one meter from the top of the log. The average depths of the damage caused by feed roller spikes in the two sections were 3.9 and 3.8 mm, respectively, indicating that there was no significant effect of bark thickness on the depth of the damage. The wood samples collected near the damaged wood zone (DW) had about 13 percent lower moisture content than those taken from the undamaged zone (UDW). This difference was statistically significant. We observed greater mean moisture content closer to the top of the log for both the samples taken near the damaged zone and the samples taken from the undamaged zone. One meter from the base of the log, the moisture content difference between the DW and UDW was 9.8 percentage points, which was statistically insignificant. By contrast, significantly lower moisture content (−16%) was observed in the DW one meter from the top of the log.
Tis červený (Taxus baccata L.) a jeho význam v přírodě blízkém obhospodařování lesů v podmínkách klimatické změny – review
European yew (Taxus baccata L.) is a key tree species in forest ecosystems, contributing to biodiversity and ecosystem stability. However, its populations have declined significantly due to historical overexploitation, habitat fragmentation, and increasing environmental pressures, particularly under ongoing climate change. This review provides a comprehensive analysis of the ecological characteristics, distribution, and silvicultural management of yew, emphasising its role in close-to-nature forest management. It discusses the species’ resilience to drought, shade tolerance and potential for adaptation to changing environmental conditions. Conservation strategies including natural and artificial regeneration, site-specific silvicultural interventions and the need for wildlife management to mitigate herbivore damage are also reviewed. The economic and pharmacological importance of yew, particularly as a source of taxanes for anticancer treatment, is also highlighted. The review also examines the sensitivity of the species to biotic and abiotic stressors and predicts its future distribution under climate change scenarios. The results highlight the need for targeted conservation measures, assisted migration, and adaptive forest management to sustain yew populations. Future research should integrate genetic diversity studies, climate modelling, and field-based silvicultural experiments to increase the species’ viability and ecological functions in European forest ecosystems.
A global review of Sitka spruce (Picea sitchensis [Bong.] Carr.): challenges and opportunities in European modern forest management
Unlocking Pinus ponderosa (Douglas ex C. Lawson) potential: a comprehensive review of results from native and introduced areas
Ponderosa pine (Pinus ponderosa) is one of the most valuable American pines growing naturally in the western and Pacific states of Arizona and California. Based on previously published research, its ecological valence makes this species suitable for introduction worldwide, including Europe. In Central Europe, climate change—the primary cause of significant dieback of native tree species, such as Norway spruce and Scots pine—has increased the need to explore new methods to ensure forest stand sustainability. Introducing previously overlooked tree species, such as ponderosa pine could help address this challenge. We reviewed 229 research sources to analyze P. ponderosa’s potential for utilization in new areas. The existing research from its native distribution range indicates ecological plasticity and strong resistance to drought and climatic extremes. Production parameters were evaluated in young European forest stands with a stand volume of 430 m3⋅ha–1 at the age of 45, pointing toward a promising use in the forestry sector. In European forestry, ponderosa pine’s importance could grow due to its adaptability to warm and dry climates and tolerance of diverse soil conditions. Moreover, the extraordinary quality and texture of the wood, as well as ponderosa’s biodiversity and ornamental functions, make the species destined to become part of future landscapes and forest ecosystems of Central Europe under changed climatic conditions. However, we also see challenges and scientific gaps associated with the management of ponderosa pine and its introduction to mixtures with native tree species without prior verification and silviculture recommendations.
Accuracy of Photo-Optical Timber Measurement Using a Stereo Camera Technology
Harvested timber requires efficient and accurate measurements for timber trade. Recently, the amount of timber that is harvested for industrial purposes is growing and methods for roundwood measurements are under constant development. Some of these solutions are with certification confirming its accuracy, some of them are proposed for general use without certification. The aim of this paper was to select the best and most useful electronic solution for timber volume masurement and calculation, and to recommend the most effective and accurate solution for future timber trade. Three photo-optical systems were tested: LogStackPro, iFovea and Timbeter. Each system was used to measure 71 stacks of pine and oak roundwood, which amounted to 3481.15 cubic meter stacked. Timber volumes obtained from the manual measurements were used as reference. Volumes obtained from the photo-optical systems were larger in comparison with the volume from manual measurements, by 3.37, 8.07 and 9.08%, in LogStackPro, iFovea and Timbeter, respectively. It was concluded from the tested systems that, currently, the most recommended solution for timber measurement will be LogStack Pro, which also presented, in most cases, the smallest deviations from the volume obtained in manual measurements.
Sustainable management of wood residues: challenges of recycling, combustion and environmental impact
In the quest for climate neutrality, the importance of sustainability and the reuse of wood waste are becoming crucial. To determine how wood waste is managed by wood and wood-based panel plants, the research aimed to focus particularly on energy recovery contribution. The research was based on quantitative data analysis obtained through computer-assisted telephone interviews. The results showed that over 57 % of respondents declared that they combusted waste to recover energy, which causes immediate CO2 emissions, instead of enabling long-term storage in wood-based products. Further research analyzed the emissions produced by combustion of the selected products: MDF boards and softwood and hardwood pellets. Laboratory tests showed that the incineration of MDF boards resulted in the emission of a number of harmful substances, which pose a threat to health and the environment. In contrast, burning pellets does not generate toxic compounds, but it still leads to the release of CO2. Research findings indicate the need for further research into the cascading wood utilization strategy, focusing on the use of wood waste in the material cycle instead of the energy cycle in order to understand and promote the EU’s sustainable development goals throughout the wood industry.
Quality of beech, birch and oak wood from stands growing on post-agricultural lands
This study assessed the quality of birch, beech, and oak for timber production on former agricultural land. All sample plots for the selected species had the same forest habitat type. All measured trees had already reached the age of felling. Thus, beech was over 120 years old, birch was over 70 years old, and oak was over 140 years old. On each plot, the same morphological features were measured for all trees: diameter at breast height, tree height, height of the first dead branch, height of the first live branch, and crown base. Based on collected data the length and percentage of the trunk suitable for industrial purposes were calculated. In general birch and beech trees from former agricultural land were higher, but had thinner trunks, when in oak reverse observation were noticed. Tree trunks from former agricultural lands have app. 7% shorter knots-free trunk section. The bigger different between forest and former agricultural land was noticed in case of the oak – 14%, then beech – 5% and birch – 1%. Considering the morphological characteristics of the trees and quality indicators, we showed that all species could be used for the afforestation of former agricultural lands to produce high-quality wood for future industrial purposes. However, it should be noticed, that in general calculated standing volume was lower on former agricultural land.
Radial Variability of Selected Physical and Mechanical Parameters of Juvenile Paulownia Wood from Extensive Cultivation in Central Europe—Case Study
The research on Paulownia cultivation and wood properties is up to date in many countries. However, there are no data on the properties of this wood defined on a microscale, on microtome samples. The main aim of this study was to find the best valorization path for the wood of Paulownia Shang Tong Hybrid F1 from an extensively cultivated plantation established in April 2017 in Poland by determining the tensile strength, the wood density, the strength-to-density ratio, and the modulus of elasticity on a cross-section of the trunk. The wood was collected from extensive plantation, where production is based on the natural resources of the habitat and ambient weather conditions, which is the opposite to the intensive cultivation model, which is the recommended model of Paulownia cultivation. The results of this study show that the mean density of the analyzed samples was approximately 210 kg/m3 when the mean value of the modulus of elasticity (MOE) was approximately 2400 MPa. The mean result for the tensile strength ratio to density was 11.25 km. In the case of anatomical structure, the increasing trend with age was noticed both in fiber and vessel characteristics. The study results provide unique data worldwide about Paulownia wood’s properties based on a cross-section of the trunk, from plantations cultivated in conditions which are not recommended by seedlings producers. The obtained data indicate that the Paulownia wood (examined) from the cultivation in this study has a technical quality similar to that of model-intensive agricultural plantations.
Variability of Structure, Volume, Carbon Sequestration, and Growth–Climate Responses of Fir, Yew, Spruce, Pine and Larch Under Global Climate Change
Global climate change is reshaping Central European conifer forests, affecting growth and ecosystem dynamics. At the same time, tree species differ in their productivity and responses to climatic conditions. Across mid-elevation monocultures of European yew (Taxus baccata L.), Norway spruce (Picea abies [L.] Karst.), Scots pine (Pinus sylvestris L.), silver fir (Abies alba Mill.), and European larch (Larix decidua Mill.), we quantified stand structure, volume, biomass carbon sequestration, and growth–climate responses (1971–2023). Silver fir reached the highest stand volume (711 m3 ha−1), with lower productivity in pine (−17.0%), larch (−22.9%), spruce (−26.0%), and yew (−70.6%). In contrast, larch maximised biomass carbon sequestration (267.7 t ha−1), whereas yew had the lowest value (87.7 t ha−1), but the greatest stand diversity (except high differentiation), while pine showed the lowest diversity. Radial growth was most constrained by warm Junes and dry Julys; an early-season multi-month drought compounded by heat further suppressed radial increments, and severe winter frosts added stress. Among the studied species, spruce was the most climate-sensitive, whereas fir and pine showed comparatively more resilience. From a practical forestry perspective, promoting structurally diverse stands with high production potential and prioritising climate-resilient tree species, especially fir, can help sustain production and stability at mid elevations under climate warming. Our results provide species-specific benchmarks for adaptive silviculture and identify the seasonal windows when growth is most vulnerable.
Wady zabytkowego drewna konstrukcyjnego
Wady drewna mają istotny wpływ na parametry mechaniczne i trwałość drewnianych konstrukcji zabytkowych. Dlatego podczas analizy stanu takich obiektów należy na wady zwracać szczególną uwagę. W artykule opisano wady zabytkowej tarcicy konstrukcyjnej. Podano sposoby klasyfikacji wad i scharakteryzowano podstawowe wady, takie jak: sęki, skręt włókien, pęknięcia, pęcherze żywiczne, zabarwienia, zgnilizny, wady powodowane przez owady, obliny, krzywizny, oraz wady wynikające z obróbki uszkodzenia mechaniczne
