Articles by Juha Laitila

The poor cost-effectiveness of mechanized planting (MECP) is the main reason for the low mechanization rate of planting. In this study, we investigated the productivity of the mechanized excavator-based planting of Norway spruce (Picea abies [L.] H. Karst.) seedlings based on data collected by the Risutec Asta documentation system. We also compared the costs of a MECP chain with two different manual planting (MAP) chains, where mounding was carried out by a crawler excavator (EXC) or a continuously advancing mounder (CONT). The MECP of seedlings was carried out using an EXC equipped with a Risutec PM-160 planting device. Generally, the nine study sites in western Finland contained few surface obstacles (e.g., the logging residues had mainly been harvested), which made the conditions very suitable for MECP. The average production time taken by the MECP was 9 h ha^-1. The operating hour (G₁₅-h) productivity averaged 215 seedlings G₁₅-h^-1 , with the mean planting time being 13.8 s seedling^-1. Loading 160 seedlings into the seedling cassette took approximately 10 min (3.8 s seedling^-1). Overall, the cost of the MECP was about 5% lower than for the EXC + MAP. However, when productivity was set at <200 seedlings G₁₅-h^-1 , the cost of the MECP was higher than that of the EXC + MAP. Based on our findings, the most cost-efficient planting chain was CONT + MAP. However, based on our results, the required level of productivity can be achieved if the sites are suitable for MECP and the machine operators are skilled.

• Kemppainen, School of Forest Sciences, University of Eastern Finland (UEF), P.O. Box 111, FI-80101 Joensuu, Finland; Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0009-0000-6184-8812 E-mail: kalle.kemppainen@uef.fi
• Kärhä, School of Forest Sciences, University of Eastern Finland (UEF), P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0002-8455-2974 E-mail: kalle.karha@uef.fi
• Laitila, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0003-4431-3319 E-mail: juha.laitila@luke.fi
• Sairanen, School of Forest Sciences, University of Eastern Finland (UEF), P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0009-0008-8632-3797 E-mail: anttsair@student.uef.fi
• Kankaanhuhta, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0001-5785-5972 E-mail: ville.kankaanhuhta@luke.fi
• Viiri, UPM-Kymmene Plc, UPM Forest, Peltokatu 26 C 4, FI-33100 Tampere, Finland https://orcid.org/0000-0003-3952-9481 E-mail: heli.viiri@upm.com
• Peltola, School of Forest Sciences, University of Eastern Finland (UEF), P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0003-1384-9153 E-mail: heli.peltola@uef.fi

The EU’s influence on national forest policies is growing, and the implementation of forest-related policies proposed by the Commission will affect the practice of forestry in Europe. For instance, the Nature Restoration Law sets concrete areal goals for restoring forest ecosystems and for conservation, the Deforestation Regulation requires meticulous tracking of wood’s origin, and the renewed Renewable Energy Directive (RED III) sets new criteria to sustainable forest biomass procurement. So far there have been no studies that have looked into the impacts from the economic and operational point of view. In this study, structural systems analysis was first performed to discover the relevant variables (and their functioning) associated with the roundwood harvesting operations and the operating environment. A scenario approach was then applied to capture the potential levels of implementation of the EU’s forest-related policies. Finally, using different scenarios (low-, moderate- and high-impact) and a systems analysis framework, the impact of alternative levels of implementation was quantified in terms of harvesting costs, measured in € m^–3. The results indicate that with the low- and moderate-impact scenarios the harvesting costs would increase by less than 10% from the current levels in three different regions in Finland. Such an increase (less than 10%) could be tolerated over a period of a few years, but a sudden increase is likely to lead to challenges to the running of businesses. With the high-impact scenario the harvesting costs would increase by between 15% and 18%, depending on the region. This magnitude of increase (of approximately a sixth) corresponds to a severe change in the roundwood harvesting operations and operating environment.

• Ahtikoski, Natural Resources Institute Finland (Luke), Tekniikankatu 1, FI-33720 Tampere, Finland https://orcid.org/0000-0003-1658-3813 E-mail: anssi.ahtikoski@luke.fi
• Väätäinen, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-6886-0432 E-mail: kari.vaatainen@luke.fi
• Anttila, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0002-6131-392X E-mail: perttu.anttila@luke.fi
• Laitila, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Mutanen, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0003-0533-9356 E-mail: antti.mutanen@luke.fi
• Lindblad, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0009-0003-6766-6587 E-mail: jari.lindblad@luke.fi
• Sikanen, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland E-mail: lauri.sikanen@luke.fi
• Routa, Natural Resources Institute Finland (Luke), Yliopistonkatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0001-7225-1798 E-mail: johanna.routa@luke.fi

Expertise in the cost-efficient utilization and treatment of brushwood on forest roadside sites is limited. In the present study, the productivity of brushwood clearing and harvesting on forest roadside sites was defined by creating time-consumption models or parameters for the aforementioned working methods. Compiled time consumption models and parameters for the brushwood clearing and harvesting can be used as a basis for evaluating alternative management practices and to determine when brushwood biomass should be harvested and when it should be left to decay. The harvesting of brushwood was based on the harwarder system and the clearing of brushwood was done with a spiral cutter, which is a novel accessory for cutting roadside vegetation. Based on the study results, the average volume of harvested brushwood and forwarding distance are the key elements that have an effect on harvesting productivity with harwarders. Correspondingly, stump diameter has a strong impact on the clearing productivity of brushwood. The plot-wise productivity of the spiral cutter in brushwood clearings varied in the range of 0.19–0.61 ha per PMh. An increase in stump diameter slowed down the clearing productivity of the spiral cutter and there was a clear step downward in clearing productivity as the average diameter increased from 30 mm to 40 mm. The machinery under study operated well and there were no interruptions due to machine breakdowns.

• Laitila, Natural Resources Institute Finland (Luke), Production systems, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Väätäinen, Natural Resources Institute Finland (Luke), Production systems, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: kari.vaatainen@luke.fi

In wintertime, the payload capacity of a timber truck is reduced by snow that accumulates on the structures of the truck. The aim of this study was to quantify the potential payload loss due to snow and winter accessories and to predict the loss with weather variables. Tare weights of eight timber trucks were collected at mill receptions in Finland over a one-year period. Monthly and annual loss of potential payload was estimated using the tare measurements in summer months as a reference. Each load was also connected with weather data at the location and time of delivery and payload loss explained by the weather data with the aid of regression models. The maximum loss of payload varied between 1560 kg and 3100 kg. On a monthly basis, the highest losses occurred in January, when the median values varied between 760 kg and 2180 kg. Over the year, the payload loss ranged between the trucks from 0.5% to 1.5% (from 1.9% and 5.1% in January) of the total number of loads in the study. Payload loss was found to increase with decreasing temperature, increasing relative humidity and increasing precipitation. Although the average payload loss was not very high, the biggest losses occur just during the season of highest capacity utilization. Big differences were also found in the tare weights between the trucks. The results of the study give incentive to develop truck and trailer structures that reduce the adherence of snow.

• Anttila, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0002-6131-392X E-mail: perttu.anttila@luke.fi
• Nummelin, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: tuomas.nummelin@luke.fi
• Väätäinen, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland E-mail: kari.vaatainen@luke.fi
• Laitila, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland https://orcid.org/0000-0003-4431-3319 E-mail: juha.laitila@luke.fi

This study was aimed at determining the maximum cost level of artificial drying required for cost-efficient operation. This was done using a system analysis approach, in which the harvesting potential and procurement cost of alternative fuel chip production systems were compared at the stand and regional level. The accumulation and procurement cost of chipped delimbed stems from young forests were estimated within a 100 km transport distance from a hypothetical end use facility located in northern Finland. Logging and transportation costs, stumpage prices, tied up capital, dry matter losses and moisture content of harvested timber were considered in the study. Moisture content of artificially dried fuel chips made of fresh timber (55%) was set to 20%, 30% and 40% in the comparisons. Moisture content of fuel chips based on natural drying during storing was 40%. Transporting costs were calculated according to new higher permissible dimensions and weight limits for truck-trailers. The procurement cost calculations indicated that with artificial drying and by avoiding dry material losses of timber, it could be possible to reduce current costs of the prevailing procurement system based on natural drying of timber at roadside landings. The maximum cost level of artificial drying ranged between 1.2–3.2 € MWh^–1 depending on the supply chain, moisture content and procurement volume of fuel chips. This cost margin corresponds to, e.g., organization, forwarding and transportation costs or stumpage price of delimbed stems.

• Laitila, Natural Resources Institute Finland (Luke), Bio-based business and industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Ahtikoski, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Paavo Havaksen tie 3, FI-90570 Oulu, Finland E-mail: anssi.ahtikoski@luke.fi
• Repola, Natural Resources Institute Finland (Luke), Management and Production of Renewable Resources, Eteläranta 55, FI-96300 Rovaniemi, Finland E-mail: jaakko.repola@luke.fi
• Routa, Natural Resources Institute Finland (Luke), Bio-based business and industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: johanna.routa@luke.fi

In Finland the increasing use of biofuel in transport presupposes a search for new raw material sources for biorefining. The aim of this study was, at the regional level, to compare the procurement costs of logging residues, stumps, delimbed stems and cereal straw for biorefining. The accumulation and procurement costs of forest chips and cereal straw were estimated within a 100-kilometre transporting distance via existing road network from an end-use-facility located in Kouvola in South-East Finland. The analyses were performed as simulated treatments in thinnings of young stands, cereal fields and regeneration fellings using existing productivity and cost functions and yield calculations based on crop statistics, the forest industry stand data and the sample plots data of the National Forest Inventory of Finland. Accumulation of raw material assortments and costs of production stages were defined per dry tonnes. Subsidies and raw material prices were excluded from consideration in the study. The results indicate that recovering logging residues requires lower costs than utilization of stumps, delimbed stems or cereal straw. Cereal straw represents an important source of biomass in Kouvola but the cost competiveness is poor compared the procurement costs of forest chips. When the annual procurement volume of biomass was 50 000 dry tonnes the cost at the plant was 49 € dry tonne ^–1 and biomass was comprised totally of logging residues. Procurement cost grew to 59 € dry tonne ^–1 when the annual procurement volume of biomass was doubled to 100 000 dry tonnes. Of that amount, the proportion of logging residues was 58.4%, stumps 24.3% and delimbed stems 17.3%. First cereal straw dry tonnes were delivered to end-use-facility, when procurement cost grew to 60 € dry tonne ^–1 and annual procurement volume of biomass was 110 000 dry tonnes.

• Laitila, Natural Resources Institute Finland (Luke), Bio-based Business and Industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Lehtonen, Natural Resources Institute Finland (Luke), Green Technology, Halolantie 31A, FI-71750 Maaninka, Finland E-mail: eeva.lehtonen@luke.fi
• Ranta, Lappeenranta University of Technology, LUT School of Energy Systems, Laboratory of Bioenergy, Lönnrotinkatu 7, FI-50100 Mikkeli, Finland E-mail: tapio.ranta@luke.fi
• Anttila, Natural Resources Institute Finland (Luke), Bio-based Business and Industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: perttu.anttila@luke.fi
• Rasi, Natural Resources Institute Finland (Luke), Bio-based Business and Industry, Survontie 9A, FI-40500 Jyväskylä E-mail: saija.rasi@luke.fi
• Asikainen, Natural Resources Institute Finland (Luke), Bio-based Business and Industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: antti.asikainen@luke.fi

Combining research into forest management stand conditions and wood supply chain processes has been missing from earlier forestry studies. There is a clear need to develop more cost-efficient small-diameter wood production, harvesting and transportation methods from first thinning, which could be used for either industrial or energy wood purposes. This study considers the total cost for small-diameter wood originating from young Scots pine (Pinus sylvestris L.) dominated stands. Pine pulpwood is the most harvested and most used roundwood assortment, use of which is expected to rise following new pulp-mill investments in Finland. In addition, utilisation of small-diameter trees directly for energy purposes has been increasing steadily in recent years. The aim of the study was to determine the cost-reduction potential of alternative forest management options and supply chains for small diameter-wood in the regional case of South Savo in eastern Finland. The total costs of three distinct scenarios were studied on the basis of forest management, first-thinning harvesting methods, and transportation: 1) industrial wood, 2) delimbed energy wood, and 3) whole trees for energy purposes. The cost-reduction potential for energy-wood supply chains from first thinning was compared to the industrial supply chain. Small-diameter delimbed wood delivered straight for energy purposes was found to be the most cost-efficient as far as the total cost of the supply chain is concerned. More cost-efficient small-diameter wood processes can be found by linking forest stand simulations with supply chain analysis.

• Karttunen, Lappeenranta University of Technology, LUT School of Energy Systems, Laboratory of Bioenergy, Lönnrotinkatu 7, FI-50100 Mikkeli, Finland E-mail: kalle.karttunen@lut.fi
• Laitila, Natural Resources Institute Finland (Luke), Bio-based business and industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Ranta, Lappeenranta University of Technology, LUT School of Energy Systems, Laboratory of Bioenergy, Lönnrotinkatu 7, FI-50100 Mikkeli, Finland E-mail: tapio.ranta@lut.fi

The primary aim of this study was to clarify the chipping productivity and fuel consumption of tractor-powered and truck-mounted drum chippers when chipping pine pulpwood at a terminal. The secondary aim was to evaluate the impact of wood storage time on the chemical and physical technical specifications of wood chips by chipping pulpwood from eight different storage time groups, using Scots pine (Pinus sylvestris) pulpwood stems logged between 2 and 21 months previously at the terminal with the above-mentioned chippers. Thirdly, the impact of sieve mesh size on the particle size distribution of wood chips from different age groups was compared by using an 80 mm × 80 mm sieve for a tractor-powered chipper and a 100 mm × 100 mm sieve for a truck-mounted chipper. With both chippers, the chipping productivity grew as a function of grapple load weight. The average chipping productivity of the tractor-powered chipper unit was 19 508 kg (dry mass) per effective hour (E₀h), and for the truck-mounted chipper the average productivity was 31 184 kg E₀h^–1. The tractor-powered drum chipper’s fuel consumption was 3.1 litres and for the truck-mounted chipper 3.3 litres per chipped 1000 kg (dry mass). The amount of extractives or volatiles did not demonstrate any statistically significant differences between storage time groups. The particle size distributions with both chippers were quite uniform, and the storage time of pulpwood did not have a significant effect on the particle size distribution in any chip size classes. One reason for this might be that the basic density of chipped wood was homogenous and there was no statistical difference between different storage times. The use of new sharp knives is likely to have affected chip quality, as witnessed by the absence of oversized particles and the moderate presence of fines. The use of narrower 80 mm × 80 mm sieves on Scots pine material does not seem to offer any benefit compared to 100 mm × 100 mm from the chip quality point of view.

• Laitila, Natural Resources Institute Finland (Luke), Bio-based business and industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juha.laitila@luke.fi
• Routa, Natural Resources Institute Finland (Luke), Bio-based business and industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: johanna.routa@luke.fi

• Laitila, Natural Resources Institute Finland (Luke), Bio-based Business and Industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: juha.laitila@metla.fi
• Ranta, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland E-mail: tapio.ranta@lut.fi
• Asikainen, Natural Resources Institute Finland (Luke), Bio-based Business and Industry, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: antti.asikainen@metla.fi
• Jäppinen, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland E-mail: eero.jappinen@lut.fi
• Korpinen, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland E-mail: olli-jussi.korpinen@lut.fi

• Jylhä, Finnish Forest Research Institute, Kannus, Finland E-mail: paula.jylha@metla.fi
• Dahl, Aalto University School of Science and Technology, Department of Forest Products Technology, Espoo, Finland E-mail: od@nn.fi
• Laitila, Finnish Forest Research Institute, Joensuu, Finland E-mail: jl@nn.fi
• Kärhä, Metsäteho Oy, Helsinki, Finland E-mail: kk@nn.fi

• Laitila, The Finnish Forest Research Institute, Joensuu, Finland E-mail: juha.laitila@metla.fi
• Heikkilä, L&T Biowatti Oy, Seinäjoki, Finland E-mail: jh@nn.fi
• Anttila, The Finnish Forest Research Institute, Joensuu, Finland E-mail: pa@nn.fi

• Laitila, Finnish Forest Research Institute, Joensuu Research Unit, Joensuu, Finland E-mail: juha.laitila@metla.fi

• Jylhä, Finnish Forest Research Institute, Kannus Research Unit, P.O. Box 44, FI-69101 Kannus, Finland E-mail: paula.jylha@metla.fi
• Laitila, Finnish Forest Research Institute, Joensuu Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: jl@nn.fi