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Weather is a significant factor influencing forest health, productivity, and the carbon cycle. However, our understanding of these effects is limited for many regions and ecosystems. Assessing the impact of weather variability on harvester productivity from plantation forests may assist in forest planning through the use of data modeling. We investigated whether weather data combined with timber harvesting attributes could be used to create a high-performance model that could accurately predict harvester productivity in Eucalyptus plantations using machine learning. Furthermore, we aimed to provide an online application to assist forest managers in applying the model. For the modeling, we considered 15 weather and timber harvesting attributes. We considered productivity as the target attribute. We subjected the database to 24 common algorithms in default mode and compared them according to error metrics and accuracy. From the timber harvesting features combined with weather features, the Catboost model can predict the productivity of harvesters in a tuned mode, with a coefficient of determination of 0.70. The use of weather data combined with timber harvesting attributes in the model is an accurate approach for predicting harvester productivity in Eucalyptus plantations, allowing for the creation of an online, free application to assist forest managers.

The negative influence of timber harvesting on the forest environment is reflected through damage to the residual trees, regeneration, and forest soil. Considering that skidding, a popular extraction method, can cause substantial and severe damage to the remaining stand, the aim of this research was to determine damage to residual trees during skidding by an LKT 81T cable skidder, including oxen bunching. The research was conducted in eastern Bosnia and Herzegovina, in an uneven-aged mixed fir (Abies alba Mill.) and spruce (Picea abies L.) forest with pine (Pinus sylvestris L.) on limestone soils. Tree felling was conducted using a Husqvarna 372 XP chainsaw. Extraction operations caused damage to 6.31% of the residual trees in the stand. The most damage was “removed bark” (65.34%) and occurred on the lower parts of the tree, the butt end (55.11%) and root collar (32.39%). The average size of the damage was 197.08 cm2. A statistically significant correlation was found between the damage position and the diameter at the breast height (p < 0.05) and the damage position and damage size (p < 0.01) by Spearman correlation analysis. The conducted analysis by the chi-squared test showed that there is a statistically significant difference in the proportion of damage for trees with different distances to the nearest skid road (p = 0.0487), but the share of damaged trees did not decrease by increasing the distance from the skid road.

The forestry industry poses a higher risk of occupational accidents than other sectors, and understanding the occurrence and characteristics of injuries and fatalities is crucial for improving the safety and health of workers and establishing future strategies. In South Korea, although occupational injuries have declined since 2010, the number of occupational accidents in forestry remains higher than that in other sectors. Occupational injuries and fatalities present considerable challenges, and thus, our objective was to analyze and compare forestry accidents between 2010 and 2020. The results indicate that the highest average number of injuries occurred among workers older than 51 years and those with less than 6 months of experience. Timber harvesting and silviculture are among the most dangerous operations in forestry. Based on the analyzed dataset, amputation and laceration injuries, as well as slip and trip injuries, were the most common, accounting for 29.2% and 22.3% of total annual occupational accidents, respectively. These results may be explained by the labor-intensive, steep terrain operations in forestry. Our findings represent an essential resource for improving worker safety and health.

Every year, logging in the world’s largest tropical forest, located within the Amazon biome, continues unabated. Although it is a preferred alternative to deforestation, the residual stand and site are impacted by logging. The objective of this review was to determine and assess the current state of research throughout Amazonia on the subject of logging impacts. To achieve this goal, a systematic approach was utilized to gather, assess and categorize research articles conducted in the Amazon biome over the last decade. Eligibility for inclusion of articles required demonstration of a direct impact from logging operations. A total of 121 articles were determined to meet the eligibility requirements and were included in this review. Articles were subdivided into three environmental categories: forest (n = 85), wildlife (n = 24) and streams (n = 12). The results of this review demonstrated that impacts from logging activities to the forest site were a direct result of the logging cycle (e.g., how often logging occurs) or logging intensity (e.g., how many trees are felled). The impacts to wildlife varied dependent on species, whereas impacts to streams were affected more by the logging system. Overall, research suggested that to attain sustainability and diminish the impacts from logging, a lower logging intensity of 10–15 m3 ha−1 and a longer logging cycle of 40–60 years would be essential for the long-term viability of forest management in Amazonia.

The conservation and sustainable management of forests across ownership groups of the conterminous USA was assessed using the Montréal Process Criteria and Indicators (C&I) framework using national forest inventory and other data. Sixty-one percent of the forest area in the USA is Privately owned (20% Corporate, 39% Family, and 2% Other Private), 37% is Public (28% Federal, 2% Local, and 7% State), and 2% is within Native American Tribal Reservation boundaries. There are many commonalities across ownership categories, but there are also important differences. A 1.1 million ha yr−1 decrease in Family forestland and a 1.0 million ha yr−1 increase in Corporate forestland (C&I 1.1.a) between 2012 and 2019 are among the main trends with implications for sustainability and influence all other aspects considered through the C&I. The majority of annual timber harvests (C&I 2.d) comes from Corporate (46%) and Family (42%) forestlands. Of the most common species, net growth to removal ratios (C&I 2.d) are less than 1.0 for three species on Tribal forestland, two species on Federal forestlands, and two species on Corporate forestlands. Disturbances (C&I 3.a and 3.b) are relatively common (ranging from 4 to 15% of forestland within an ownership category) across ownership categories with the highest proportion of disturbances being caused by diseases and pests on Federal forestland. Differences in the legal and institutional frameworks across ownership categories (Criterion 7) influence how the forest resources can be managed and how policies, programs, and services can be designed and implemented to help maintain and enhance the flow of forest-based goods and services. This analysis helps illustrate that sustainability is complex, C&I are imperfect, and there are additional elements, such as recreational access and ownership/management objectives, that would be helpful for comparing across ownership categories. But the Montréal Process C&I framework helps elucidate the relative threats among ownership categories, in particular the loss of Family forestland to non-forest uses and the increase in disturbances across most ownership categories, and the relative opportunities across ownership categories, including the sustainable supply of timber from Corporate and Family forestlands and the relatively high tree, and presumably broader, biodiversity especially on Local and Other Private forestlands.

The aim of this study is to reveal the weight values of the criteria that are effective in selecting the most suitable vehicle types in forest products transportation by using hybrid fuzzy multi-criteria decision-making method. According to different scenarios, the goal is to determine which vehicle alternative is the most suitable in given conditions. In the results obtained from the study, it is determined that the most important main criterion in determining the eligibility of vehicle alternatives in forest products transport is the environmental damage criterion, while the other main criteria are cost and operational performance, in order of importance. In the scope of the study, transportation scenarios including different operational conditions were created and the suitability of vehicle alternatives was evaluated according to the scenarios, taking into account CO2 emission and road surface damage risk criteria. Transportation of coniferous and broadleaved tree species makes a difference in vehicle suitability rankings according to transportation scenarios. In addition, it was observed that the variability in the amount of roundwoods to be transported affects the vehicle suitability rankings. It will be beneficial to consider the total weight of the forest product to be transported and the tree species in the selection vehicle type.

Mountainous hardwood mixed stands offer challenges to timber harvesting operations in practice, including a harsh climate, variable topography, steep terrain, and large-sized timbers. This paper aims to develop productivity and cost models for a mountain-ground-based harvesting operation across the terrain (e.g., slope conditions), stand (e.g., tree volume) environmental (e.g., weather), and yard (e.g., winching distance) variables and to assess GHG emissions related to the equipment in use. This development was implemented in a timber harvesting practice under single-tree selection in mountainous forests of Iran where a motor-manual chainsaw is used for felling and a rubber-tired cable skidder is used for log extraction. The average delay-free productivity was 4.55 m3 for felling and 14.73 m3 h−1 for skidding. Lower production costs and higher productivity rates were observed over the gentle slopes and in sunny conditions. The average production costs ranged between USD 4.27 m−3 for felling and USD 5.35 m−3 for skidding. The average emissions ranged between 0.96 kg m−3 for felling and 7.06 kg m−3 for skidding in snowy conditions over steep slopes. The study’s results confirm avoiding harvesting operations on steep slopes (greater than 35%) and in extreme weather conditions to obtain higher work efficiency and to minimize adverse effects of machinery on forest ecosystems. The results should be of use to harvest managers and forest planners considering the application of ground-based harvesting operations using a semi-mechanized system on a range of operating conditions in mountain hardwood stands.

The provision of forest ecosystem services (such as biodiversity, water and soil protection, and recreation) is often associated with a reduction in timber harvesting. In the case of private forests, such a situation requires institutional solutions that allow the economic balance of forest management to be maintained. The aim of the study was to find out the average value of monetary compensation private forest owners would expect in case of timber harvesting restrictions. The study was conducted with a random sample of 1003 forest landowners. The average value of expected compensation ranged from PLN 2300/year/ha (which corresponds to the price of about 12 m3 of wood in Poland) under the condition of no restrictions on timber harvesting but the need to apply indicated of forest management methods, to PLN 4900/year/ha in the model assuming a total ban on harvesting. In general, higher compensation was expected by farmers who stated that they sold timber and those whose agricultural area was larger than the average in Poland. When harvesting restrictions are low, the expected compensation is influenced by the age and gender of the respondent, or the number of people in the household.

Timber transportation is an essential and often unprofitable segment of the wood supply chain. This study evaluated the profitability of individual timber deliveries for log truck owners in the US South. Origin and destination data were collected from 909 deliveries from 257 harvest sites. Travel time and distance were estimated using ArcGIS and GPS tracking. Monte Carlo Simulation was used to calculate 1000 unique combinations of payload, harvest site turn-time, mill turn-time, and percent-loaded km, yielding a dataset of 909,000 deliveries. Hauling costs and revenues for each delivery were estimated using published estimates. Driver wages were estimated in two ways: an hourly wage of $30.60 (USD) and 30% of the gross revenue from the load being delivered. Logistic regression was used to evaluate the relationship between six dependent variables and profitability. Only 14% of deliveries were profitable when the driver was paid an hourly wage versus 42% when the driver was paid 30% of gross revenue. Deliveries with one-way haul distances between 49 and 113 km (31–70 mi) were least likely to be profitable. Many deliveries could be profitable if logging businesses and mills reduced turn-times to under 20 min at mills and 30 min at harvest sites.

The aim of the study was to determine the mental workload of a harvester operator when working in late thinning and in windthrown stands of the same type and age, using eye movement patterns as an indicator. Eyeball movement variability was analysed using the eye tracking method. The mean duration of eyesight fixations in windthrown stands was shorter than in the control undamaged stands by about 20% (444 ms and 534 ms, respectively). The mean time of eyesight movements (saccades) in the windthrown stands was shorter than in the control undamaged stands by approx. 15%. The largest differences between the duration of saccades in the windthrown and control stands were observed between the cutting of trees and cutting logs off their root plates: the saccades were longer by about 20% when working in the control stands (49 ms) as compared to the windthrown stands (43 ms). Large differences in the duration of saccades between the windthrown area (42 ms) and the control area (47 ms) were also found when travelling between successive operation sites. In both types of stands, the shortest saccades were observed during processing: 39 ms. Summary durations of saccades observed during the processing of successive trees occurred in sequences showing repeated periods of variable eyeball activity, where longer saccades were followed by shorter ones. Documented more variability of eyesight activities of the harvester operator performing the operations of processing and moving is new standard of eye balls activities for the more taxing work conditions presented by windthrown stands.

Research Highlights: The felling of hung up trees is considered by literature in the field as an activity with a high injury risk. The low work productivity in the felling of hung up trees is wrongly cited by workers in order to justify various more or less safe work techniques. Background and objectives: The purpose of this paper was to determine work productivity in the felling of hung up trees when this activity has a well-defined structure with stages and specific activities that would allow workers to assess injury risk correctly. In addition, this paper aims to identify the moment when workers should give up the manual felling of hung up trees with a hand winch and start using specialized logging equipment. Materials and methods: The research was conducted in the Eastern Carpathians in a spruce (Picea abies (L.) H. Karst.) tree stand where clear cutting normally takes place. A single team of workers was used consisting of two chainsaw operators—a main one and a secondary one. This team had a high level of qualification and experience in the operations performed. For the felling of hung up trees, the technique based on rotating the tree around a pivot with a hand winch was used. Time was measured in seconds by using the continuous time study method. Results: The results indicated that work productivity decreases with the number of times the traction line needs to be repositioned. It decreases from 3.477 trees·h−1 (in trees where no repositioning is necessary) to 1.402 trees·h−1 (when the repositioning takes place twice). In trees that needed the repositioning of the traction line, safety rules were broken in the following ways: crossing over the tensioned cable of the traction line, the main chainsaw operator being positioned inside the triangle formed by the hung up trees and the anchorage points of the pulley and the hand winch as well as the operator being positioned very close to the hung up tree stem base while the latter is being tied. That is why, if the repositioning of the traction line is necessary, the question is—would it be better to give up the manual felling of hung up trees and start using specialized equipment? Conclusion: The felling of hung up trees must be regarded and understood, first and foremost, through the perspective of reducing injury risk and protecting workers. Thus, the work productivity of 3.477 trees·h−1 can be considered acceptable for trees that need no extra repositioning of the traction line or when the time consumed does not go over 17 min·tree−1.

This case study examines the performance of the Igland Hauler employed in small diameter Eucalyptus clear-cut operations in Guangxi, China. A yarding crew of eight persons was monitored by a snap back elemental time study for 19.23 SMH (scheduled machine hours), with 159 yarding cycles and a yarded log volume at landing of 49.4 m³ solid over bark. A gross-productivity of 2.50 m³/SMH and net-productivity of 5.06 m³/PMH0 (productive machine hours excluding delay times) was achieved, leading to a machine utilization rate of 49.5%. The costs of the yarder and associated overhead as well as the personnel costs of a large crew with eight people sum up to extraction costs of 50.24 USD/m³. The high costs make it difficult to compete economically with the locally common manual extraction system as long as abundant labor at a low hourly rate is available in the region. Further performance improvement through skill development, but also technical and organizational system modification in conjunction with rising wages and decreasing labor force in rural primary production will determine the justification of employing such yarding systems. However, new silvicultural regimes with extended rotations and supply requirements of the forest products industry in China demand new operational systems.

Forested catchments generally present conserved aquatic ecosystems without anthropogenic disturbances; however, forest management operations can degrade these environments, including their water quality. Despite the potential degradation, few studies have analyzed the effects of forest management in subtropical regions, especially in forest plantations with intensive management, such as Eucalyptus plantations in Brazil. The intensive management of those plantations is characterized by fast-growing, short rotation cycles, and high productivity. This study aimed to assess the effects of Eucalyptus plantations harvesting on the concentration and exportation of nutrients and suspended solids in subtropical streams. Results showed that clear-cut harvesting and subsequent forest management operations do not alter most of the concentration of nitrate, potassium, calcium, and magnesium. The concentration of suspended solids increased during the first year after timber harvesting in all studied catchments, however, the increases were statistically significant in only two catchments. In the first year after harvest, it was observed an increment of water yield/precipitation ratio at three catchments, which also increased export of nutrients and suspended solids. Our results showed that harvesting of fast-growing Eucalyptus forest plantations partially affected sediment exports and did not compromise water quality in the studied catchments. However, the catchment land-use design, especially related to road density and land-use composition, showed significant relationship with sediment exportation.

Steep country harvesting has been identified as the main bottleneck to achieving greater profitability in the forestry sector of New Zealand and Australia. An improvement of efficiency, work safety and environmental sustainability should be realized by developing an advanced steep terrain timber harvesting system based on innovative Austrian technology. To identify the best suitable configuration of a cable yarder for steep terrain harvesting, user preferences based on an online survey (conjoint analysis) have been evaluated to answer the following questions: (1) What attributes of a new yarder design are most important to consumers? (2) Which criteria do stakeholders consider when selecting a cable yarder? (3) What are the weights representing the relative importance of criteria? Using eight specific design scenarios a fourth question, being which cable yarder concept is the best, was also answered. This case study shows that conjoint analyses is an effective tool to assess, rate and subsequently integrate design characteristics. Based on the results of the analysis, a cable yarder prototype will be manufactured in Austria and transferred to New Zealand for testing and demonstration.

Chainsaws with chipper-type chains are widely used in timber harvesting. While existing research on such saws assumes a continuous cutting process, the objectives of the present study were to determine whether or not that is true, as well as to measure instantaneous cutting forces and active cutting time (the time during which the chainsaw cutters are actually engaged with the wood sample). Tests were conducted on a special experimental stand enabling cutting force measurement with a frequency of 60 kHz. The test material was air-dry pine wood. The feed force range was 51–118 N. The chain was tensioned. The study revealed considerable variability in instantaneous cutting force, which was correlated with the rotational speed of the chainsaw engine, as indicated by frequency analysis. Furthermore, the process of cutting with chainsaws was shown to be discontinuous, and a cutter engagement time ratio was defined as the proportion of active cutting time to the overall time of chainsaw operation when making the cut. It was also found that active cutting time was directly proportionate to the applied feed force and inversely proportionate to the rotational speed of the chainsaw engine. The results may be practically applied to establish an optimum range of rotational speed that should be maintained by the operator to maximize cutting efficiency.

In order to accommodate foreseen climate change in European forests, the following are recommended: (i) to increase the number of tree species and the structural diversity; (ii) to replace unsuitable species by native broadleaved tree species, and (iii) to apply close-to-nature silviculture. The state forest department of Baden-Württemberg (BW) currently follows the concept of Forest Development Types (FDTs). However, future climatic conditions will have an impact on these types of forest as well as timber harvesting operations. This Geographic Information System (GIS)-based analysis identified appropriate locations for main FDTs and timber harvesting and extraction methods through the use of species suitability maps, topography, and soil sensitivity data. Based on our findings, the most common FDT in the state forest of BW is expected to be coniferous-beech mixed forests with 29.0% of the total forest area, followed by beech-coniferous (20.5%) and beech-broadleaved (15.4%) mixed forests. Where access for fully mechanized systems is not possible, the main harvesting and extraction methods would be motor manual felling and cable yarding (29.1%). High proportions of large dimensioned trees will require timber extraction using forestry tractors, and these will need to be operated from tractor roads on sensitive soils (23.0%), and from skid trails on insensitive soils (18.4%).