Silva Fennica vol. 58 no. 4 | 2024

• Heräjärvi, School of Forest Sciences, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0002-7256-3887 E-mail: henrik.herajarvi@uef.fi

• López, Inland Norway University of Applied Sciences, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, P.O. Box 2400, Koppang, Norway https://orcid.org/0009-0006-6860-3408 E-mail: lucas.lopez@inn.no
• Sjølie, Inland Norway University of Applied Sciences, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, P.O. Box 2400, Koppang, Norway https://orcid.org/0000-0001-8099-3521 E-mail: hanne.sjolie@inn.no
• Nabhani, Inland Norway University of Applied Sciences, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, P.O. Box 2400, Koppang, Norway E-mail: abbas.nabhani@inn.no
• Aguilar, Swedish University of Agricultural Sciences, Department of Forest Economics, SE-901 83 Umeå, Sweden E-mail: francisco.aguilar@slu.se

Highly mechanized timber harvesting and timber logistics emit CO₂. In turn, the provided timber stores CO₂ from the atmosphere as biogenic carbon. This basic assumption resulted in the calculation of net carbon storage of supplied timber. For this, we first developed a formula that represents the carbon content of freshly harvested timber. Coniferous wood contains about 734 kg CO₂ m^-3 and deciduous wood about 1000 CO₂ m^-3. Contrary to this, CO₂ emissions from trucks, harvesters, and forwarders were calculated using the variable parameters for actual diesel consumption and the distance to the sawmill and constant parameters for the transport of the machine to the stand, lubricants, transport of operators, loading, and fabrication, supply, and maintenance. The method was tested on an actual harvest. The principal findings are that the method is practical, the net carbon storage of the supplied timber is reduced by 1.5% to 5% by harvesting and transport activities, and timber logistics is the largest contributor to emissions. The CO₂ emissions for harvesters and forwarders are about 4 kg CO₂ m^-3, and for downstream timber logistics across all assortments and distances is 11 kg CO₂ m^-3. We conclude that the emissions are low, vis-a-vis the storage capacity. Emissions and a standardized calculation model are imperative. The model developed here for mapping the net carbon storage of roundwood highlights the climate protection performance of timber and contributes to optimizing climate-friendly timber supply chains.

• Kaulen, KWF - Kuratorium für Waldarbeit und Forsttechnik e.V., Spremberger Straße 1, 64823 Groß-Umstadt, Germany; University of Freiburg, Chair of Forest Operations, Werthmannstr. 6, 79085 Freiburg, Germany https://orcid.org/0009-0006-2633-8132 E-mail: alexander.kaulen@kwf-online.de
• Engler, University of Freiburg, Chair of Forest Operations, Werthmannstr. 6, 79085 Freiburg, Germany https://orcid.org/0000-0003-2104-8209 E-mail: benjamin.engler@foresteng.uni-freiburg.de
• Purfürst, University of Freiburg, Chair of Forest Operations, Werthmannstr. 6, 79085 Freiburg, Germany https://orcid.org/0000-0001-9661-0193 E-mail: thomas.purfuerst@foresteng.uni-freiburg.de

In the past decade, research and several surveys have indicated that the competence of higher forestry education graduates does not meet the requirements of working life regarding supervisory and management skills. The aim of this study was to discover what kind of supervisory and management competence is required in the daily tasks of early-career forestry professionals, and to what extent the teaching of these skills would be advisable to include in higher forestry education. The study was implemented through a Webropol survey of the Master’s of Forestry graduates and forestry engineers graduated between 2018–2021, which mapped their supervisory and managerial duties and skills. The study population was 1046 people, of which 30.4% responded to the survey. The principal finding was of an apparent extensive need for the abovementioned skills, as supervisory duties are typical in the work of forestry professionals soon after their graduation. In this study, approximately one fifth of the employed respondents worked in a supervisory position, one third had supervisory or managerial duties, and half had an indirect network of subordinates. Supervisory skills were seen important for all forestry professionals regardless of their position. Moreover, self-management, team management, and well-being and occupational health management were regarded as important skills. However, there appeared to be notable gaps in all these skills. The study results contribute to improving working life orientation in higher forestry education. Based on these findings, we recommend that teaching of these subjects should be implemented by integrating the topics into field-specific courses.

• Manninen, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland; South-Eastern  Finland University of Applied Sciences, P.O. Box 68, FI-50101 Mikkeli, Finland https://orcid.org/0009-0001-4234-7649 E-mail: heikki.manninen@xamk.fi
• Lehtimäki, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland https://orcid.org/0000-0002-9061-8984 E-mail: hanna.lehtimaki@uef.fi
• Kilpeläinen, TTS Työtehoseura, P.O. Box 5, FI-05201 Rajamäki, Finland E-mail: riitta.kilpelainen@tts.fi
• Lautanen, TTS Työtehoseura, P.O. Box 5, FI-05201 Rajamäki, Finland E-mail: eila.lautanen@tts.fi
• Kärhä, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0002-8455-2974 E-mail: kalle.karha@uef.fi

The moose (Alces alces L.), a common large herbivore in the boreal region, impairs forest regeneration by browsing on tree seedlings and saplings. Moose prefer deciduous species, but during winter more coniferous seedlings are used. We used meta-analyses, separately for deciduous and coniferous seedlings, for evaluating whether excluding moose browsing affected seedling density and height. In addition, we compared (1) deciduous seedling proportion, (2) stand density, (3) elapsed time from fencing and (4) estimated moose density with moose exclusion effect sizes. Fencing had a positive effect on coniferous seedling height. With more deciduous trees in a seedling stand, the fencing effect for both seedling height and density of coniferous seedlings decreased. On the other hand, the fencing effects increased with denser stands. At some point effect sizes turned to negative, and conifer species varied in their response to browsing. This implies that deciduous seedlings can protect conifers from browsing by moose up to some mixing ratio, but when deciduous seedling densities are too high, their negative effect increases, presumably through increased competition. Our results suggest that a moderate deciduous admixture in conifer-dominated mixed seedling stands can decrease moose damage but also underline the significance of timely silvicultural measures to minimize the negative effects of excessive deciduous seedlings and too dense stands. Due to differences in coniferous and deciduous species, as well as their compositions and amounts in studied experiments, more studies adjusted to local conditions are still needed to give exact measures for silvicultural recommendations.

• Domisch, Natural Resources Institute Finland (Luke), Natural Resources, Yliopistokatu 6B, FI-80100 Joensuu, Finland https://orcid.org/0000-0001-7026-1087 E-mail: timo.domisch@luke.fi
• Huuskonen, Natural Resources Institute Finland (Luke), Natural Resources, Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: saija.huuskonen@luke.fi
• Matala, Natural Resources Institute Finland (Luke), Natural Resources, Yliopistokatu 6B, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-5867-5057 E-mail: juho.matala@luke.fi
• Nikula, Natural Resources Institute Finland (Luke), Natural Resources, Ounasjoentie 6, FI-96200 Rovaniemi, Finland https://orcid.org/0000-0001-8372-8440 E-mail: ari.nikula@luke.fi

• Viljanen, University of Helsinki, Faculty of Agriculture and Forestry, Latokartanonkaari 7, 00014 Helsingin yliopisto, Finland https://orcid.org/0000-0001-7166-8022 E-mail: anne.viljanen@helsinki.fi
• Kurttila, Natural Resources Institute Finland (Luke), Research and Customer Relationships, Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0001-5290-4771 E-mail: mikko.kurttila@luke.fi
• Toppinen, University of Helsinki, Faculty of Agriculture and Forestry, Latokartanonkaari 7, 00014 Helsingin yliopisto, Finland https://orcid.org/0000-0003-0910-1505 E-mail: anne.toppinen@helsinki.fi

• Eyvindson, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Campus Ås, Norway; Natural Resource Institute Finland (Luke), Bioeconomy and Environment, Laatokartanonkaari 9, 00790 Helsinki, Finland https://orcid.org/0000-0003-0647-1594 E-mail: kyle.eyvindson@nmbu.no
• Kangas, Natural Resources Institute Finland (Luke), Bioeconomy and Environment, Yliopistokatu 6, 80100 Joensuu, Finland https://orcid.org/0000-0002-8637-5668 E-mail: annika.kangas@luke.fi
• Nahorna, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Campus Ås, Norway https://orcid.org/0000-0002-5497-0315 E-mail: olha.nahorna@nmbu.no
• Hunault-Fontbonne, Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Campus Ås, Norway https://orcid.org/0009-0004-1864-5162 E-mail: juliette.hunault@nmbu.no
• Potterf, Ecosystem Dynamics and Forest Management Group, Technical University of Munich, Hans Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany https://orcid.org/0000-0001-6763-1948 E-mail: maria.potterf@tum.de

Since the 1950s, more than 200 000 km of roads have been built in Sweden’s forests, making them easily accessible and open to multiple uses. The aim of this study was to review the impacts of forest roads in Sweden from a broad perspective encompassing social, ecological, and environmental factors. The Swedish case is interesting because it has an extensive network of permanent forest roads which were built primarily for forestry-related transportation but are currently used by many other stakeholders for many different purposes. Forest roads not only facilitate transportation of wood, machinery, personnel, and equipment into and out of the forest but also enable emergency response to wildfires and support berry and mushroom picking, hunting, recreation, tourism, and access to second homes. The roads increase the opportunities for members of the public to experience forests in various ways. Conflicts arise when different interests collide, for example when the interests of the forest owner clash with those of commercial berry-picking companies, tourism entrepreneurs, or reindeer (Rangifer tarandus L.) herding. Forest roads may have ecological impacts such as barrier and disturbance effects, fragmentation or loss of habitats, altering fauna movement patterns, and changing the composition of plant and insect species. The environmental impacts of forest roads relate to, among other things, hydrology, water quality, and erosion. Predicted changes in the climate are likely to place new demands on Swedish forest roads but, despite their extent, this review shows that there is only a small amount of rather fragmented research on their social, ecological, and environmental consequences. Overall, few studies appear to cover both social and ecological/environmental factors and their interactions, either in Sweden or elsewhere. This review provides examples of such interactions in the case of Sweden, and suggests that more research into these and the specific social, ecological, and environmental factors involved is warranted.

• Ring, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden https://orcid.org/0000-0002-8962-9811 E-mail: eva.ring@skogforsk.se
• Wallgren, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden; Swedish University of Agricultural Sciences, Department of Wildlife, Fish, and Environmental Studies, 907 36 Umeå, Sweden https://orcid.org/0000-0002-3172-4496 E-mail: martha.wallgren@skogforsk.se
• Mårald, Umeå University, Department of Historical. Philosophical and Religious Studies, 901 87 Umeå, Sweden https://orcid.org/0000-0002-2291-9910 E-mail: erland.marald@umu.se
• Westerfelt, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden https://orcid.org/0000-0003-2040-8305 E-mail: per.westerfelt@skogforsk.se
• Djupström, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden; Swedish University of Agricultural Sciences, Department of Wildlife, Fish, and Environmental Studies, 907 36 Umeå, Sweden https://orcid.org/0000-0003-4536-7765 E-mail: line.djupstrom@skogforsk.se
• Davidsson, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden https://orcid.org/0009-0007-2736-8656 E-mail: Aron.davidsson@skogforsk.se
• Sonesson, Skogforsk (The Forestry Research Institute of Sweden), Uppsala Science Park, 751 83 Uppsala, Sweden https://orcid.org/0000-0002-2018-7496 E-mail: Johan.sonesson@skogforsk.se

The consensus on the factors affecting harvester productivity is generally widely acknowledged in the discipline. However, research results regarding the effect of forking on productivity are diverse. Some studies show that harvester productivity is halved when harvesting double stems compared to single-stem trees, while other studies indicate that forking does not necessarily decrease harvester productivity. These differences in study results can depend on what is considered forking. In our study, the forking occurred above the breast-height level. We defined codominant stems as forked trees too large to be multi-tree handled. In contrast, we defined double crowns as forked trees that could be multi-tree handled. The objective of our study was to analyse how the presence of codominant stems and/or double crowns affects harvester time consumption. The study was conducted in Sweden in 2022, involving two operators and two large harvesters. The 45-year-old Pinus contorta Douglas ex Loudon-dominated stand was clearcut during the study. We found that the presence of codominant stems doubles harvester time consumption per tree, while double crowns had only a minor impact on harvester time consumption. Additionally, total time consumption increased linearly with increasing diameter at breast height. Based on these findings, we recommend that forked trees be removed already during thinning when they can still be time-efficiently multi-tree handled. Dealing with forked trees later during the rotation cycle, when they are too large for multi-tree handling, is excessively time-consuming.

• Manner, Skogforsk, Uppsala Science Park, 751 83 Uppsala, Sweden https://orcid.org/0000-0002-4982-3855 E-mail: jussi.manner@skogforsk.se
• Lundström, Skogforsk, Uppsala Science Park, 751 83 Uppsala, Sweden E-mail: hagos.lundstrom@skogforsk.se