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How the scots pine and beech aging process affects wood
This study investigates the effects of aging trees on wood properties, which are caused by climate change, the withdrawal of coniferous species from Central Europe, and the increased crown sweep in old beech stands. The research was carried out in old tree stands with a high proportion of Scots pine (Pinus sylvestris L.) and beech (Fagus sylvatica L.) species. The collected material was from five tree pine stands aged between 151 and 182 and three beech stands between the ages of 165 and 184. The samples were subjected to an analysis of wood properties such as density and modulus of elasticity. The results and findings of this study indicate that the Scots pine currently reaches the optimal wood tissue quality at around 80 years of age, which is approximately 20 years earlier than the species’ anticipated cutting age. However, the beech, which reaches maturity at about 120–140 years, reaches the maximal quality of wood tissue already at the age of 80–90 years. Above the age of 110, the quality of beech wood (density and modulus of elasticity) decreases. Moreover, it is necessary to emphasize that the radial trend of wood density does not coincide with the trend of the modulus of elasticity. Additionally, it is found that wood density is not a perfect representation of its mechanical qualities; it can, however, be regarded as a measure of the technical quality of wood tissue. The results indicate that the pine and the beech that grow on the European Plain mature faster and reach technical quality earlier than just a couple of decades before.
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.
Influence of cutting attachment on work efficiency, fuel consumption and environmental pollution from plastic wire during tending of young forests with brush cutters
Abstract Petrol brush cutters are among the most widely used devices for tending young forests. During this work, environmental pollution is generated by the combustion of fuel and by the discarding of pieces of the plastic cutting line. The aim of this study was to compare operating parameters and the degree of plastic pollution from the cutting line, and to determine fuel consumption during tending of young forest with the use of a petrol brush cutter equipped with different cutting attachments: a plastic wire head, and 2-, 3-, and 24-tooth cutting blades. Measurements were made in the course of work on 2–3-year-old oak plantations containing two vegetation types (herbaceous and mixed). It was found that the most efficient cutting attachment was the wire head, but its use was associated with significant wire and fuel consumption. In the mixed vegetation case, wire consumption was 575.89 g*ha−1, which is comparable to eighteen polyethylene terephthalate (PET) bottles. Similar performance and significantly lower fuel consumption were obtained with the 2-tooth blade. In addition, when using cutting blades, there was no wire consumption and thus no plastic pollution of the environment. It was concluded that, in order to eliminate plastic pollution and reduce fuel consumption while achieving satisfactory working efficiency, the use of wire heads should be abandoned in favor of metal cutting blades.
The influence of some morphological characteristics of pine logs on the results of calculating their volume by different methods
Wood quality of silver birch Betula pendula Roth stands growing on former agricultural lands in Poland
Accuracy, repeatability and time consumption of selected digital measurement methods of roundwood stacks
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.
Wood Quality of Pendulate Oak on Post-Agricultural Land: A Case Study Based on Physico-Mechanical and Anatomical Properties
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.
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.
How the Spruce Ageing Process Affects Wood
Climate change and the gradual phaseout of the spruce from Central Europe inspired us to study the effects of the ageing process of trees on wood properties. This study was conducted in old tree stands with significant involvement of the spruce (Picea abies (L.) H. Karst) in the ages between 122 and 177 years. The study material (samples) was collected from the selected trees to study wood properties such as density, resilience to compressive strength, resilience to bending strength, and modulus of elasticity. The results and findings of this study indicate that the spruce currently reaches the optimal technical quality of wood tissue at approximately 60 years of age. It is approximately 20 years earlier than the planned cutting age for the species. This could be due to water stress which led to adaptive changes in the wood tissue and earlier technical maturation of the wood in the studied trees. Significant radiant variabilities of wood properties of the Norway spruce were observed. It was determined that wood density does not fully reflect its mechanical properties, and it can be considered an indicator of the technical quality of wood tissue, but only within a limited scope. The results obtained may not only be applied in optimising the use of wood from spruce stands. They can also indicate the need to change the approach to managing spruce stands and their conversion towards broadleaf species.
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.