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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.

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.

European forests are facing ongoing climate change, and certain tree species are being critically impacted. The Norway spruce (Picea abies (L.) Karst.) is one of the most sensitive species to climate fluctuations, a fact manifesting itself through massive dieback resulting in a lack of high-quality timber and timber market destabilization. Therefore, the possibility of wood substitution with non-native spruce species, namely, black spruce (Picea mariana (Mill.) Britt., Sterns, et Poggenburg), Serbian spruce (Picea omorika (Pančić) Purk.), and blue spruce (Picea pungens Engelm.), under the specific conditions of forest reclamations with great potential for future afforestation was tested. Wood density, modulus of rupture, and modulus of elasticity were used to evaluate wood quality in comparison with native Norway spruce. The results confirmed that only the Serbian spruce reached the quality of Norway spruce and even exceeded it in terms of wood density (P. omorika 525 kg·m−3 vs. P. abies 517 kg·m−3) and exhibited comparable parameters with regard to other properties. The density of the other species was significantly lower for blue spruce (476 kg·m−3) and black spruce (468 kg·m−3). A similar trend was found for other wood parameters, which confirmed that Norway spruce quality was nearly comparable with that of Serbian spruce. On the other hand, black spruce and blue spruce did not match the quality of Norway spruce. The within-stem variability of the properties tested was low for all the spruce species examined. In conclusion, the Serbian spruce showed great potential for future usage in forest management and is one of the possible methods of Norway spruce replacement in times of unprecedented forest disturbances under the effects of global climate change.

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.

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.

Expanding the base of raw materials for use in the production of wood-based materials, researchers and panel manufacturers around the world are increasingly trying to produce panel prototypes from raw materials available in a given area and climate, or by managing waste from wood industry processing. The aim of the study was therefore to test the hypothesis that forest residues de-rived from Scots pine roundwood harvesting have the same suitability for the production of three-layer particleboard as the wood of the most valuable part of the Scots pine stem, by comparing selected properties of raw wood material and final product—particleboard. Characterization of both the raw material and the physical-mechanical and hygienic properties of the produced panels was carried out. For these panels from the tree trunk, MOR was 14.6 N/mm2, MOE 1960 N/mm2 and IB 0.46 N/mm2. The MOR and IB values turned out to be higher for the panel from the branch and are 16.5 and 0.72 N/mm2, respectively. Excessive swelling of the panels resulted in all manufactured particleboards meeting the standardized performance requirements of EN 312 for interior furnishing panels (including furniture) for use in dry conditions (type P2).

The beginnings of the petrol chainsaw in forestry date back to the early 20th century. For more than a century, engineers have been refining the chainsaw to make it as efficient and comfortable as possible for woodcutters. In recent years, environmental protection and the reduction in CO2 emissions policies have been particularly prominent. As a consequence, the use of battery-powered electric tools, including chainsaws, has become increasingly widespread, especially in gardening. However, electric chainsaws have limited battery capacity and, therefore, are not used daily in forestry. This study aimed to determine the efficiency of a battery-powered chainsaw during commercial thinning. The research compared the work efficiency of the petrol chainsaw Dolmar PS 5000 and the battery-powered Echo ECCS-58V during commercial thinning in a 14-year-old pine stand. In seven repeats, the following variables were measured each time: working time, working area and noise load to which the logger was exposed. Obtained results were used to calculate average productivity, a weighted equivalent continuous sound pressure level (LAeq) and a weighted noise exposure level normalized to a nominal 8h working day (LEX,8h). The average operating length of the battery-powered chainsaw was 00:41:26 and was comparable to the working length of a petrol chainsaw, for which the average working time was 00:41:41. The average work output of the petrol chainsaw was 100 m2/h higher. The recorded noise exposure, LAeq and LEX,8h, were lower for the battery-powered chainsaw. Using a battery-powered chainsaw was less workload, because of smaller noise levels and zero emissions. This study found that six fully charged batteries allowed the user to effectively complete a work shift. It can be concluded that battery-powered chainsaws can be used effectively during commercial thinning. Further tests should be run in winter to determine the effect of low temperatures on battery consumption.

The aim of the study was to analyse the changes in the infection rate development inside the beech stem as a result of browsing by deer (Cervus elaphus). The research materials were collected from three research plots located in the Polanów Forest Inspectorate from March to April 2020. For the study, 80 beech trees were selected, for which the size of the fallow tree, the percentage of the section taken from its centre infected with rot, and the number of years passed since the tree was wounded were determined. The study shows that the infection affects only the rings formed before the tree was injured. The average size of stem rot was 7.75% of its area, and it spread at the rate of 2.52% of the cross-sectional area per year. The analysis of the obtained results proved that both the size of the wound (splits) and the time elapsed since the tree was damaged are significantly correlated with each other. It is also possible to build a model for estimating the size of decay in stunted beech trees based on easy-to-determine predictors, such as maximum wound width and elapsed time since tree damage.

Silver birch ( Roth) is classified in diffuse-porous wood category. In this case structure of wood tissue is quite similar across whole cross-sectional area. The aim of this study was to analyse cross-section variability of moisture content (MC) of growing silver birch wood, significant hardwood species in Polish forests. Investigations were performed on 120 model trees. In the trunk of each model tree, an increment core was collected at breast height. Samples were collected of 30 different trees in four different seasons. The greatest MC was observed during winter, lowest MC in summer. Differences in MC were statistically significant only between winter versus spring, summer, and autumn. Distribution of MC on cross-section was similar in each season. The greatest average value was observed close to pith, then it was decreasing in bark direction. The greatest difference between observed in spring â 19.51% (pâ

To determine the appropriate final use of wood from a particular tree species, it is first necessary to know its properties. Methods that use wood samples taken directly from the trunk of a growing or felled tree are very time-consuming and require a great deal of manual work. Non-destructive methods may be more effective and much faster, thanks to the use of advanced technologies. The resistance drilling can be used to determine the variation in wood density along the radius of the stem. The main aim of the present study was to determine the basic density of the wood on a cross-section of the trunk of oak trees and to investigate the correlation of the results with those obtained by drilling the same trees with the IML RESI-PD 400. The results of Spearman’s correlation test showed strong positive correlations between all examined properties. We observed a trend whereby the density of the wood and Resi amplitude increased in direct proportion to the width of the annual rings. The results of linear regression show a strong relationship between examined properties. This study provide evidence that the Resi is an appropriate tool for non-destructive determination of wood density.

This study evaluated within-stem differences in the moisture content of stored summer-harvested oak wood with respect to drying method. The felled oaks were naturally dried for eight weeks, from 4 July to 29 August 2017. We analyzed two methods of preparation and storage: a transpiration drying method (W), and an air-drying method for stem-wood (L). Transpiration drying is a better method for oak stems than air-drying. Statistically significant differences between drying methods were found after six weeks of storage. This coincided with complete wilting of the leaves. However, signs of wilting and leaf color change appeared earlier, between the second and fourth weeks of storage. In parallel, in scenario W, a statistically significant difference in MC of sapwood was observed between the second and fourth weeks of storage. Such a phenomenon was not observed in scenario L. The MC of heartwood also gradually decreased, especially in scenario W. Explanation of this phenomenon lay outside the scope of this study; however, it indicates how the structure and properties of wood, in addition to storage conditions and methods, influence the efficiency of biomass drying in the harvesting area.

Survival in variable conditions of wind exposure depends on the strategy of trees in adapting to environmental constraints. There are many studies investigating the effect of wind on the adaptation of trees, but little attention is paid to the properties of the wood, particularly within-stem variability. In the present work, an analysis was made of within-stem variability of the density and mechanical properties of Scots pine wood from parts of stands with different wind exposure (stand edge, forest interior). The research was carried out in north-western Poland, in seven selected pine stands (without other species in the canopy) aged from 82 to 87 years. In each stand, three trial plots were marked, each at a different distance from the edge of the stand. The first plot was immediately adjacent to the edge (0–20 m), the second was at a distance of 30–50 m, and the third was at a distance of 60–80 m. Generally, wind exposure, defined by the distance from the windward edge, did not significantly affect the tree morphology and wood properties. A statistically significant difference was found only for the modulus of elasticity (MOE), between stand edge and forest interior. Trees growing at a distance from the stand edge compensate for their greater stem slenderness with higher elasticity. A certain growth response to wind loads is also represented by the within-stem variability of wood. We found that within-stem variability of wood at the stand edge is higher than in the forest interior. At various points along the stem, the wood density and strength were generally higher on the eastern radius (on the leeward side of the stem). Different wind resistance requirements at the stand edge and in the interior lead to combinations of tree architecture and wood properties that enable the best resistance to wind loads.

This study evaluated changes in mass and the moisture content of stored summer-harvested Scots pine small diameter roundwood subject to different types of preparation and storage (drying methods). Small diameter roundwood was naturally dried for three months, from 15 June to 15 September 2018. We analyzed three methods of preparation and storage. First, logs 1.2 m in length were stored and air-dried in piles (C). In the second case, a transpirational drying method was used (W). Thirdly and finally, we used air-drying for logs with lengths between 9.6 and 14.4 m (L) stored in the harvesting area. Within three months, the moisture content of the logs stored in piles decreased by 22.9 percentage points. With the transpirational drying method (W) the decrease in moisture content was 10.0 percentage points. In scenario L, at the end of the storage period the moisture content was lower by 15 percentage points. Within three months, the density of the roundwood stored in piles decreased to 700 kg/m3, which is about 140 kg/m3 more than in scenarios W and L. Cutting stemwood into short segments and storing it in a pile appears to have positive effects on drying performance. Overall, this study shows that, for Scots pine wood, air-drying is a better method than transpirational drying.