Kärhä Kalle, PhD.

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.

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.

The EU’s climate and energy framework and Energy Efficiency Directive drive European companies to improve their energy efficiency. In Finland, the aim is to achieve carbon neutrality by 2035. Stora Enso Wood Supply Finland (WSF) had a target, by 2020, to improve its energy efficiency by 4% from the 2015 level. This case study researches the use of the forest machine fleet contracted to Stora Enso WSF. The aims were to 1) clarify the forest machine fleet energy-efficiency as related to the engine power; 2) determine the fuel consumption and greenhouse gas (GHG) emissions from wood-harvesting operations, including relocations of forest machines by trucks; and 3) investigate the energy efficiency of wood-harvesting operations. The study data consisted of Stora Enso WSF’s industrial roundwood harvest of 8.9 million m3 (solid over bark) in 2016. The results illustrated that forest machinery was not allocated to the different cutting methods (thinning or final felling) based on the engine power. The calculated fuel consumption totalled 14.2 million litres (ML) for harvesting 8.9 million m3, and the calculated fuel consumption of relocations totalled 1.2 ML, for a total of 15.4 ML. The share of fuel consumption was 52.5% for harvesters (cutting), 39.5% for forwarders (forest haulage), and 8.0% for forest machine relocations. The average calculated cubic-based fuel consumption of wood harvesting was 1.6 L/m3, ranging from the lowest of 1.2 L/m3 for final fellings to the highest of 2.8 L/m3 in first thinnings. The calculated fuel consumption from machine relocations was, on average, 0.13 L/m3. The calculated carbon dioxide equivalent (CO2 eq.) emissions totalled 40,872 tonnes (t), of which 21,676 t were from cutting, 16,295 t were from forwarding, and 2,901 t from relocation trucks. By cutting method, the highest calculated CO2 eq. emissions were recorded in first thinnings (7340 g CO2 eq./m3) and the lowest in final fellings (3140 g CO2 eq./m3). The calculated CO2 eq. emissions in the forest machine relocations averaged 325 g CO2 eq./m3. The results underlined that there is a remarkable gap between the actual and optimal allocation of forest machine fleets. Minimizing the gap could result in higher work productivity, lower fuel consumption and GHG emissions, and higher energy efficiency in wood-harvesting operations in the future.

The aim of the study was to provide a comprehensive overview of global long-distance road transportation of industrial roundwood. The study focused on the maximum gross vehicle weight (GVW) limits allowed with different timber truck configurations, typical payloads in timber trucking, the road transportation share of the total industrial roundwood long-distance transportation volume, and the average long-distance transportation distances and costs of industrial roundwood. The study was carried out as a questionnaire survey. The questionnaire was sent to timber transportation logistics experts and research scientists in the 30 countries with the largest industrial roundwood removals in Europe, as well as selected major forestry countries in the world (Argentina, Australia, Brazil, Canada, Chile, China, Japan, New Zealand, South Africa, Türkiye, the United States of America and Uruguay) in February 2022, and closed in May 2022. A total of 31 countries took part in the survey. The survey illustrated that timber trucking was the main long-distance transportation method of industrial roundwood in almost every country surveyed. Road transportation averaged 89% of the total industrial roundwood long-distance transportation volume. Timber truck configurations of 4 to 9 axles with GVW limits of around 30 tonnes to over 70 tonnes were most commonly used. The results indicated that higher GVW limits allowed significantly higher payloads in timber trucking, with the lowest payloads at less than 25 tonnes, and the highest payloads more than 45 tonnes. The average road transportation distance with industrial roundwood was 128 km, and the average long-distance transportation cost in timber trucking was €11.1 per tonne of timber transported. In the entire survey material, there was a direct relationship between transportation distance and transportation costs and an inverse relationship between maximum GVW limits and transportation costs. Consequently, in order to reduce transportation costs, it is essential to maximise payloads (within legal limits) and minimise haul distances. Several measures to increase cost- and energy-efficiency, and to reduce greenhouse gas emissions in road transportation logistics, are discussed in the paper. On the basis of the survey, it is recommended that up-to-date statistical data and novel research studies on the long-distance transportation of industrial roundwood be conducted in some countries in the future.

Prior tree marking is used to guide loggers or forest machine operators on which trees to cut to achieve the desirable silvicultural quality of a thinning treatment. In the future, this beneficial but expensive human work could be automated with advanced driver assistance systems. This study aimed to investigate the effect of conventional prior tree marking on cutting productivity and harvesting quality of the first and later thinnings. A comparative time study was conducted with four experienced harvester operators. The operators thinned 4825 stems with the cut-to-length (CTL) harvesting method in eight thinning stands. The time consumption of the different time elements of cutting work was measured to model the cutting productivity with average values or regress these values against the stem volume or density of removal. Prior tree marking increased the cutting productivity by an average of 2.8% in the first thinnings and 2.7% in later thinnings by reducing the time consumption of boom-out (positioning the harvester head for cut) and moving. The operator effect was notable, even though only experienced operators participated in the study. For some operators, prior tree marking did not make cutting work more efficient, and sometimes hampered it. Prior tree marking improved the quality of the remaining stands in thinnings by producing a more accurate density of remaining trees after the harvesting operation in relation to thinning guidelines. When the stands were not marked, the operators chose trees of poor quality with almost the same accuracy as the forester. These findings lay the foundation for the next-generation operators’ guidance and decision support systems, which could detect trees around the harvester and guide the operator in tree selection and managing better thinning intensity in cutting work. Although prior tree marking increased productivity only marginally, the improvement in the quality of harvesting operations must be acknowledged.