A survey of the Finnish mechanized tree-planting industry in 2013 and its success factors

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Productivity and Cutting Costs of Thinning Harvesters

High harvesting costs are the main problems in first thinnings. Machines with lower operating costs could be one potential solution for cost-efficient first thinnings. The research investigated the productivity of the four most widely used small harvesters, i.e. thinning harvesters, and their cutting costs. Data were also collected on the productivity relationships between working methods and the differences between operators. In the time studies involving thinning harvesters, the Nokka Profi and Timberjack 770 represented the larger, more expensive machines, while the Sampo-Rosenlew 1046X and Valtra Forest 120 represented the more compact, less expensive thinning harvesters. The productivity per operating hour (E15 including delay times shorter than 15 minutes) of the thinning harvesters was found to be 5.6-10.3 m3/ E15 (stem size 50-100 dm3) in first thinnings and 9.1-12.7 m3/ E15 (100-150 m3) in second thinnings. The productivity figures of the individual machines were similar. The differences were mainly attributable to the operators. The time study showed that the differences between operators using the same machines were as great as 40%. The cutting costs for the thinning harvesters were 7.5-14.2 US$/m3 (50-100 dm3) in first thinnings when using the Nokka/Timberjack machine group. The corresponding costs for the Sampo/Valtra machine group were 5.7 and 10.5 US$/m3. It would appear that thinning harvesters can be operated at the same productivity level of medium-sized harvesters in thinnings and, consequently, they can be run at cutting costs lower than those of medium-sized harvesters

Productivity and Costs of Harwarder Systems in Industrial Roundwood Thinnings

In several studies, the harwarder has proven to be a more cost-effective wood harvesting system than the traditional two-machine (harvester-forwarder) system, especially when the average stem size of the marked stand is relatively small, the removals per hectare/stand low (i.e. the harvesting site small), and the forwarding distance short. One of the strengths of a harwarder is considered to be the lower relocation costs compared to the two-machine system. The time consumption of harwarder relocations have not, however, been reported in the previous harwarder studies. Metsäteho Oy conducted a follow-up study of harwarders in industrial roundwood harvesting, and also investigated the relocations of harwarders. A total of five – three Ponsse Wisent Dual and two Valmet 801 Combi – harwarders were examined in the follow-up study. The amount of harvested industrial roundwood in the study totalled nearly 30,000 m3. The cost calculations showed that the harwarder system is more competitive than the twomachine system when the average stem size of the marked stand is relatively low, i.e. less than 110–170 dm3. Furthermore, harwarders were the most competitive at low-removal harvesting sites. The proportion of the total working time of harwarders used in relocations between harvesting sites was 2.5%, and the effective relocation time was, on the average, 1.3 hours/relocation. The study results underlined that it makes sense to harvest relatively small-removal and small-diameter thinning stands marked for harvesting with a harwarder while, conversely, it is more worthwhile to harvest sites with larger removals and trees using a two-machine harvester-forwarder system, thereby raising the profitability of forest machine business

Potential Traffic Levels after Increasing the Maximum Vehicle Weight in Environmentally Efficient Transportation System: The Case of Finland

The objective of this research was to study how the maximum vehicle weight (76 t) will affect roundwood transportation in environmentally efficient transportation system. Actual traffic levels were assessed with calculations based on the vehicle configurations (60, 64, 68, and 76 t) a year after the weight limit was raised. Consequences of this change were also assessed for predicted future traffic levels. The reduction in operational vehicle-km was 12.5% (versus a decrease of 9.3% based on the legal weight), though this may underestimate the long-term prediction (26.7%) that will be achieved when the roundwood transportation sector adjusts fully to the higher maximum weight limit. The migration of loads to heavier vehicles did not create any wood harvesting problems for 60, 64 and 68 t vehicle configurations. However, 76 t vehicles were often volume-constrained, so it was harder to achieve the maximum weight. The main operational challenge was pulpwood (3.5 and 4.0 m) when onboard loaders were not available. Based on comparison of roundwood length measurements as an indicator of volume-constraint vehicles, the best practice system is discussed to enable an efficient transportation system for sustainable wood procurement

Mechanized Energy Wood Harvesting from Early Thinnings

The felling and bunching of small diameter trees in Finland is still largely carried out manually using a chain saw and clearing saw. The felling of small diameter trees has been developed and mechanized. In addition to the high felling costs of small trees, the move towards mechanized harvesting is also caused by a shortage of professional lumberjacks, the possibility of all-year-round mechanized energy wood harvesting, and an increasing demand for energy wood. The research investigated the productivity, costs and silvicultural result of the guillotine blade equipped, multi-tree-processing Naarva-Grip 1600-40, for small diameter energy wood harvesting. Work-studies were carried out in six young stands at the first thinning stage. In mechanized energy wood harvesting with the Naarva-Grip 1600-40, an average of 73% of the trees felled were multi-tree-processed. The multi-tree-processed proportion increased to 96% in dense Scots pine (Pinus sylvestris L.) sites with small trees. One bunch consisted of approximately 3.2 trees. The average density and volume of removal had the greatest effect on the productivity of the felling-bunching work. Felling-bunching was carried out on the sites at a rate of 106-422 trees per effective hour (E0, excluding delay times). Productivity on the different sites varied from 3.0 to 7.2 m3/E0, giving an average of 4.7 m3/E0 (weighted by felling volume) with an average tree size on the site of 32 dm3. When the size of the felled trees was under 20 dm3, the felling-bunching costs were over 20 US$/m3. When the average tree size on the site increased to 50-70 dm3, the felling-bunching costs approached the 10 US$/m3 level. During the research, the Naarva-Grip 1600-40 proved to be competitive compared to the other multi-tree-processing, energy wood felling heads on the market. In order to keep the felling-bunching costs at a reasonable level, mechanized harvesting should be targeted at sites where the average size of the trees removed is over 30 dm3, and the energy wood volume at felling over 30 m3/ha

Attitudes of Small and Medium-Sized Enterprises towards Energy Efficiency in Wood Procurement: A Case Study of Stora Enso in Finland

Stora Enso Wood Supply Finland (WSF) was certified to the ISO 50001 Energy Efficiency Management System standard in 2015. At Stora Enso WSF, the goal is to improve energy efficiency by 4% by 2020 from 2015. Improving the energy efficiency of wood procurement (i.e. logging and timber trucking) enterprises is currently one of the main focus areas for energy efficiency development at Stora Enso WSF. In order to clarify its state-of-the-art in the business of wood procurement enterprises at Stora Enso WSF, logging and timber-trucking entrepreneurs were interviewed in November and December 2017. The survey data consisted of 25 logging and 25 timber-trucking entrepreneurs. The coverage rate of both entrepreneur groups was 73.5% in the survey. The results indicated that timber-trucking enterprises highlight more energy efficiency and fuel efficiency than logging enterprises. For instance, the timber-trucking entrepreneurs underscored more energy efficiency in their acquisition decisions of new vehicles and the greater role of fuel efficiency in the energy-efficient business than logging entrepreneurs during 2016 and 2017. Furthermore, the survey results revealed that logging and trucking enterprises can improve energy efficiency in their business by organizing more energy efficiency education (i.e. economical and anticipated driving training) for their machine operators and truck drivers. There is a positive attitude towards energy efficiency among both logging and timber-trucking entrepreneurs. This creates a solid background to deepen and continue energy-effective work in the wood supply chain between the enterprises and Stora Enso WSF in the future

Metsäautotienkäyttäjien hiljainen tieto : Haastattelututkimus puutavara-autokuljetusyrittäjille ja kuljettajille

Metsäautotieverkoston käytettävyys on tärkeässä asemassa niin metsäteollisuuden ympärivuotisen puuraaka-aineen saatavuuden kuin huoltovarmuudenkin kannalta. Suomen tiestön kokonaispituudesta valtaosa koostuu metsäautoteistä sekä muista sorapintaisista yksityisteistä. Metsäautoteiden käytettävyyttä rajoittavat etenkin kelirikkoajat keväisin ja syksyisin. Lisäksi metsäautotieverkoston hoidon ja kunnostuksen laiminlyöminen aiheuttaa sen kunnon rapautumista. Puutavaran kaukokuljetuksessa käytettävien ajoneuvoyhdistelmien kasvaneet suurimmat sallitut mitat ja massat asettavat nykyisen metsäautotieverkoston yhä suuremmalle rasitukselle. Tutkielman tavoitteena oli kartoittaa metsäautotienkäyttäjien hiljaista tietoa liittyen kantavuuden arviointiin, metsäautoteiden ongelmiin, nykytilaan ja toimintamalleihin liikuttaessa huonokuntoisella soratiestöllä. Lisäksi selvitettiin metsäautoteiden kunnon vaikutusta yritystoimintaan sekä toiveita ja tarpeita kuljettajaa avustavien, ennakkotietoa tuottavien karttajärjestelmien kehittämiseen. Tutkimusaineisto kerättiin haastattelemalla puutavaran autokuljetusyrittäjiä sekä heidän kuljettajiaan. Haastatteluihin osallistui yhteensä 30 henkilöä, joista puutavaran autokuljetusyrittäjiä oli 25 ja autonkuljettajia viisi. Yhtä yrittäjää lukuun ottamatta kaikki yrittäjät ajoivat myös itse säännöllisesti puutavara-autoa. Haastattelut toteutettiin valtakunnallisesti etäyhteydellä Microsoft Teams -alustalla tai puhelimitse tammi-maaliskuussa 2023. Haastattelujen vastauksista pyrittiin löytämään mahdollisia alueellisia sekä haastateltujen työkokemukseen ja ikään sekä lisäksi yrityksen kokoon ja ikään liittyviä tilastollisia eroja. Sorapintaisilla teillä liikkumista rajoittavimpana tekijänä pidettiin tien kantavuutta. Tien kantavuuden arvioimisessa tärkeimpänä tekijänä esiin nousi maapohja tielinjalla ja sen ympärillä. Metsäautoteiden kunnon heikkenemiseen johtaneista syistä ylivoimaisesti merkittävimpänä pidettiin tiestön kunnostuksen ja hoidon laiminlyöntiä. Yritystoiminnan kannattavuuteen vaikuttavista metsäautoteiden kunnon aiheuttamista lisäkustannuksista kasvanutta polttoaineen kulutusta pidettiin tärkeimpänä. Suurimmat erot haastateltujen keskuudessa muodostuivat eripituisen työkokemuksen omaavien henkilöiden välille: pitkään (yli 20 vuotta) alalla toimineet eivät kokeneet tarvitsevansa ennakkotietoa teiden kunnosta yhtä paljon kuin alalla lyhyemmän aikaa työskennelleet. Kokemuksen myötä karttuva hiljainen tieto auttaa kuljettajia arvioimaan paremmin teiden kulkukelpoisuutta ja siten tukemaan kuljettajien päätöksentekoa metsäautoteillä liikuttaessa. Ennakkotietoa tieolosuhteista pidettiin hyödyllisenä liikuttaessa paikoissa, joista ei ole aiempaa paikallistuntemusta. Vastauksissa ei löydetty merkittäviä alueellisia eroja; erojen selvittämiseksi olisi haastateltava suurempaa joukkoa metsäautotienkäyttäjiä eri toiminta-alueilta ja myös eri toimialoilta

Development of a wood damage monitoring system for mechanized harvesting

Cut-to-length harvesting is a cost-efficient method of the wood supply chain. However, it risks causing stem damage in the mechanized process of thinning forest stands, thereby reducing the growth and technical quality of the remaining trees, which would then be exposed on the increased vulnerability to fungal diseases. For these reasons, it is critical to support quality monitoring of harvesting machines. One way to support quality monitoring is through the application of machine vision solutions. In this study, the damaged stems were photographed systematically from a strip road. The success of the stem-damage detection was analyzed to determine the relationships between successful detection, stand condition, and the image-processing technique. Statistically meaningful relationships were identified via logistic regression analysis, which can be used in selection of tailored image processing technique. The study indicated that the quality-monitoring system of mechanized harvesting could be improved by an increased focus on developing the multi-view photogrammetry of stem damages according to different stand conditions. Further, refining the machine learning system would support the need to determine accurate image-processing thresholds of the texture of stem damages. Then, the overall proportion of successful stem-damage detections will be 89%. These improvements of the quality monitoring system will provide the efficient thinning process in the sustainable wood supply from forests to forest industry. The implementation of such a system could be much broader, initially under Nordic conditions and then in other countries as well, given that its development takes into considerations the significant calibration factors of local conditions