Template-Type: ReDIF-Article 1.0 Author-Name: Pavel Nevrkla Author-Workplace-Name: Department of Engineering, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: Luboš Staněk Author-Workplace-Name: Department of Engineering, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: Jindřich Neruda Author-Workplace-Name: Department of Engineering, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Title: Analysis of selected functional parameters of saw chains Abstract: Results obtained from the research study focused on the functional parameters of five saw chains tested on a test bench equipped with an electrically driven chain saw brought a number of findings. One of the most important of them is the significant difference between the cutting rates of round and square chains. The cutting rate of square chains R = 27.9 cm2.s-1 is about 12% higher than the cutting rate of round chains. The influence of the chain construction on the chain cutting rate was conclusively demonstrated - the cutting rate of chains with a square profile is higher than the cutting rate of round-profile chains. It was further found out that although the specific energy Em = 77.8 Ws.cm-2 is by ca. 7% lower in the square chain than in the round chain, Student's t-test did not reveal any statistically significant difference in the data on the specific energy consumption of round and square chains, i.e. the influence of the chain design on the specific energy consumption of the chain at cutting was not clearly demonstrated. Other findings, for example, showed that working with a loose saw chain on the guide bar impairs parameters of the chain operation or that energy demands of cutting with the saw chain are directly proportional to wood density (hardness) and increase with the decreasing wood moisture. Yet another finding was learning the energy flow structure, which indicated that 46% of total power input is consumed by the electric motor alone for its operation while only about 7% goes for driving the chain movement along the bar (without cutting) and power input required for cutting is approximately 46%. Keywords: chainsaw, cutting rate, energy consumption, power saw, structural arrangement Journal: Journal of Forest Science Pages: 72-85 Volume: 71 Issue: 2 Year: 2025 DOI: 10.17221/64/2024-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/64/2024-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202502-0001.txt Handle: RePEc:caa:jnljfs:v:71:y:2025:i:2:id:64-2024-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Tomáš Kotek Author-Workplace-Name: Department of Engineering, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: Jindřich Neruda Author-Workplace-Name: Department of Engineering, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Title: Dynamic parameters of lowering loads at gradual tree felling Abstract: The lowering of loads at gradual tree felling is the riskiest activity performed by tree climbers. During this activity, great forces emerge and act on the felled tree, while the tree climbers use the tree itself to anchor and secure their stance. This research aims to find out whether certain methods of work or the use of certain rigging for lowering loads exhibit positive features in reducing the forces acting on the anchoring point of the rigging system. The work methodology consists of three operations: (i) the calculation of the coefficient of shear friction for the combination of 4 ropes and 5 lowering devices - altogether 20 combinations; (ii) the mathematical modelling of the maximum forces acting on the lowering loads of known weight; and (iii) the verification of mathematical modelling using a series of measured experiments of lowering loads of known weight. The research results present the calculation of the shear friction coefficient for 20 combinations of rigging rope and lowering devices. The maximum magnitudes of the forces which may act on the upper anchoring point of the rigging system at the known load weight were additionally calculated. A total of 240 force values were measured when a load of 12 kg in weight falls according to a predetermined model situation. The results indicate that the greatest influence on decreasing the impact force generated by the falling load is that of the load attachment, reduced load weight, shortened length of the fall or elongation of the total rope length in the rigging system. The differences in the coefficients of shear friction are apparent in the results of measurements, too. Keywords: arboriculture, friction, rigging, ropes, tree climbing Journal: Journal of Forest Science Pages: 86-98 Volume: 71 Issue: 2 Year: 2025 DOI: 10.17221/66/2024-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/66/2024-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202502-0002.txt Handle: RePEc:caa:jnljfs:v:71:y:2025:i:2:id:66-2024-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Alex Bumbera Author-Workplace-Name: Department of Forest Economics and Policy, Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovak Republic Author-Name: Daniel Halaj Author-Workplace-Name: Department of Forest Economics and Policy, Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovak Republic Author-Name: Iveta Hajdúchová Author-Workplace-Name: Department of Forest Economics and Policy, Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovak Republic Title: Will cultural and regulatory forest services provide enough balance to provisioning services in forest enterprise portfolios in future? Marketing case studies of selected forest enterprises in Slovakia Abstract: The study aims to identify the difference between the current and future strategic management of forest ecosystem services (FES) portfolios in public enterprises of Slovakia. The case studies focus on forest enterprises in Košice, Banská Štiavnica, Kremnica, and Bratislava, representing the best practice examples of providing cultural services in the country. A marketing decision-making model, Boston Consulting Group (BCG) matrix, was used to analyse each company's current FES portfolio. Content analysis assessed the data collected from interviews with managers of the public forest enterprises. Duncker's forest management approaches classification was applied to evaluate the future strategic management of the FES portfolio, and a horizon of 10 years was set. According to the results, the urban forest enterprise in Bratislava is an example of receiving a subsidy from the capital for building and reconstructing recreational facilities. Therefore, this FES portfolio is and will be the most balanced. The portfolio of the forest enterprises in Košice, Kremnica, and Banská Štiavnica will remain unchanged for the next decade, and they plan to use a combination management approach that caters to economic, ecological, and social needs and objectives. Urban forests in Bratislava will focus even more on close-to-nature forestry. Keywords: business strategy, forest ecosystem services, forest management, interviews, qualitative research Journal: Journal of Forest Science Pages: 59-71 Volume: 71 Issue: 2 Year: 2025 DOI: 10.17221/68/2024-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/68/2024-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202502-0003.txt Handle: RePEc:caa:jnljfs:v:71:y:2025:i:2:id:68-2024-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Roman Dudík Author-Workplace-Name: Department of Forestry and Wood Economics, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Petra Palátová Author-Workplace-Name: Department of Forestry and Wood Economics, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Aleš Kůs Author-Workplace-Name: Department of Forestry and Wood Economics, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: David Homolka Author-Workplace-Name: Department of Forestry and Wood Economics, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Andreas Nikodemus Author-Workplace-Name: Department of Forestry and Wood Economics, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Potential for monetisation and utilisation of wood raw material from pioneer tree species stands in the Czech Republic Abstract: Pioneer tree species in the Czech Republic include birch, alder and aspen. From an economic point of view, birch seems to be the most promising. Greater use of timber from pioneer tree species in higher value-added products is currently limited by the low stocks of birch, alder and aspen in forest stands. A price survey was carried out in the Western Highlands region in the central part of the Czech Republic to obtain basic information on the prices of assortments of pioneer tree species. The prices of five assortments of raw timber were surveyed for the period 2019-2023. Very few of the prices of pioneer tree species were found for assortments of II and IIIC; these assortments are not actually produced and, therefore, not traded by the respondents. For the roundwood assortments (quality II, IIIAB), it cannot be clearly stated that any of the preparatory timber species (birch, alder, aspen) always achieved a higher price during the observed period. Only in 2023 was it possible to see higher prices for quality IIIAB assortments of alder. Birch of quality V had the highest price of the observed prices for this timber assortment for the pioneer tree species during the period under review. When using a system approach, considering the information on the prices of the timber assortments is also important for deciding on the optimal species composition of the regenerating forest stands. In the case of the Czech Republic's commercial tree species, this information is available at the national level. However, the situation is quite the opposite for the timber assortments of pioneer tree species, where information on their prices is completely lacking. This confirms the fact that the market for assortments of timber from pioneer tree species in the Czech Republic is basically non-existent, the main reason being the low volume of these assortments placed on the market. Keywords: alder, aspen, birch, price investigation, timber market Journal: Journal of Forest Science Pages: 99-111 Volume: 71 Issue: 2 Year: 2025 DOI: 10.17221/101/2024-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/101/2024-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202502-0004.txt Handle: RePEc:caa:jnljfs:v:71:y:2025:i:2:id:101-2024-JFS