scholarly journals Productivity and Cost Models for the First Commercial Thinning of a Scots Pine Stand Using an Excavator with an Arbro 400S Harvester Head and a Farm Tractor Coupled to a Logging Trailer

2021 ◽  
Author(s):  
Krzysztof Leszczyński ◽  
Arkadiusz Stańczykiewicz ◽  
Dariusz Kulak ◽  
Grzegorz Szewczyk ◽  
and Paweł Tylek
Keyword(s):  
Scots Pine ◽  
Timber Harvesting ◽  
Utilization Rate ◽  
Cost Models ◽  
Individual Tree ◽  
Minimum Diameter ◽  
Thinning Intensity ◽  
Commercial Thinning ◽  
Farm Tractor ◽  
Forwarding Set

The objective of the present work was to determine the productivity and costs of timber harvesting and skidding during the first commercial thinning of a Scots pine stand. The analyzed harvesting set consisted of a mini-excavator (34 kW) with an stroke harvester head (gripping range: 4–30 cm), and a farm tractor coupled to an logging trailer with a hydraulic crane. Merchantable timber (roundwood with a minimum diameter of 5 cm inside bark) was harvested from a 25-year old planted Scots pine stand growing on a grid of 1.4×1.8 m. The study showed the productivity of the mini-harvester range from 3.09 to 3.47 m3∙PMH15 -1, and that of the forwarding set to be 4.07 m3∙PMH15 -1. The analyzed model of productivity as a function of individual tree volume and thinning intensity was statistically significant, but the intensity parameter was significant only on plots located along wide access trails (3.7 m) and insignificant on plots located along the narrow access trial (2.5m). The intertree distance was not found to be significant. The calculated net machine costs for the forwarding set and mini-harvester were 36.12 Euro∙PMH 1 and 52.47 Euro∙PMH-1, respectively. An increase in the utilization rate of the harvesting set to 80% would reduce the timber harvesting and skidding costs to 22.07 Euro∙m-3.

scholarly journals Estimation of Productivity and Costs of Using a Track Mini-Harvester with a Stroke Head for the First Commercial Thinning of a Scots Pine Stand

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 870
Author(s):  
Krzysztof Leszczyński ◽  
Arkadiusz Stańczykiewicz ◽  
Dariusz Kulak ◽  
Grzegorz Szewczyk ◽  
Paweł Tylek
Keyword(s):  
Scots Pine ◽  
Timber Harvesting ◽  
Intensity Parameter ◽  
Minimum Diameter ◽  
Thinning Intensity ◽  
Usage Rate ◽  
Commercial Thinning ◽  
Farm Tractor ◽  
Hydraulic Crane ◽  
Wide Access

The aim of the present work was to estimate the productivity and costs of timber harvesting and forwarding during the first commercial thinning of a Scots pine stand. Three harvesting models were introduced and compared: narrow trail, wide access trail, and schematic extraction. The analyzed harvesting equipment consisted of a track mini-excavator (34 kW) with a stroke harvester head (gripping range 4–30 cm), and a farm tractor coupled to a logging trailer with a hydraulic crane. Merchantable timber (roundwood with a minimum diameter of 5 cm inside bark) was harvested from a 25-year-old planted Scots pine stand growing on a grid of 1.4 m × 1.8 m. The study showed the productivity of the mini-harvester ranged from 3.09 to 3.47 m3/PMH15 (productive machine hours plus 15 min), and that of the forwarding equipment to be 4.07 m3/PMH15. The analyzed model of productivity as a function of tree volume and thinning intensity was statistically significant, but the intensity parameter was significant only on plots located along wide access trails (3.7 m) and insignificant on plots located along narrow access trails (2.5 m). The distance between trees was not found to be significant. The calculated net machine costs for the forwarding equipment and track mini-harvester were EUR 36.12 and 52.47 per PMH, respectively. An increase in the usage rate of the harvesting equipment to 80% would reduce the harvesting and forwarding costs to EUR 22.07/m3.

Commercial thinning stimulates natural regeneration in spruce–fir stands

2014 ◽  
Vol 44 (3) ◽  
pp. 173-181 ◽  
Author(s):  
Matthew G. Olson ◽  
Spencer R. Meyer ◽  
Robert G. Wagner ◽  
Robert S. Seymour
Keyword(s):  
Natural Regeneration ◽  
Tree Regeneration ◽  
Managed Forests ◽  
Individual Tree ◽  
Thinning Intensity ◽  
Advance Regeneration ◽  
Commercial Thinning ◽  
Individual Tree Growth ◽  
Spruce Stands ◽  
Large Size Class

Understanding the response of tree regeneration following commercial thinning treatments can improve planning in managed forests dependent on natural regeneration. We used long-term commercial thinning experiments in eastern spruce–fir stands of Maine, USA, to test two hypotheses: (1) commercial thinning increases the density of tree regeneration and (2) tree regeneration density increases with increasing thinning intensity. A decade after thinning, densities of softwood and hardwood regeneration were 10 times greater in thinned stands than unthinned stands. The abundance of small softwood (0.11–0.60 m tall) was highest in lower intensity thinning treatments, whereas medium (0.61–1.40 m tall) and large (≥1.41 m tall to 8.90 cm diameter at breast height) softwoods increased proportionally with thinning intensity, a pattern related to a higher rate of recruitment in more open stands created by heavier thinning. Hardwood density generally increased with thinning intensity and developed into a significant component of the large size class. Softwood regeneration density was higher in older spruce stands than younger fir stands, which may be due to greater abundance of advance regeneration, higher residual stand mortality, and greater harvest disturbance in older spruce stands. However, acceptable softwood stocking was achieved in all replicates of thinning treatments. Therefore, in addition to providing higher individual-tree growth and merchantable yield, commercial thinning in eastern spruce–fir stands also increases regeneration density. The rate of recruitment also increased as thinning intensity increased, thus stimulating understory regeneration similar to that of a shelterwood establishment cut.

Predicting Logging Residue Volumes in Alaska

2021 ◽  
Vol 67 (2) ◽  
pp. 119-124
Author(s):  
Erik C Berg ◽  
Eric A Simmons ◽  
Todd A Morgan ◽  
Stanley J Zarnoch
Keyword(s):  
Predictive Models ◽  
Tree Species ◽  
Timber Harvesting ◽  
Individual Tree ◽  
Growing Stock ◽  
Prediction Tools ◽  
Breast Height ◽  
Logging Residue ◽  
The Creation ◽  
Forest Managers

Abstract Alaska forest managers seek information on how timber harvesting practices change the creation of postharvest woody residues. To predict residue volumes, researchers investigated how residue ratios—growing-stock residue volume per mill-delivered volume—related to readily available data on logging site and tree attributes in Alaska. Residue ratios were not related to logging site-level variables but were related to individual tree variables with predictive models. Ratios varied widely by tree species and were predicted to increase with larger stump height and larger small-end used diameters and decline exponentially with increasing diameter breast height (dbh) to approximately 25 inches. Ratios were then predicted to increase progressively in larger dbh trees. Results from this study update previous findings in other US Northwest states and can be used to produce or improve residue prediction tools for Alaska land managers.

scholarly journals Presenting MASSIMO: A Management Scenario Simulation Model to Project Growth, Harvests and Carbon Dynamics of Swiss Forests

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 94 ◽  
Author(s):  
Golo Stadelmann ◽  
Christian Temperli ◽  
Brigitte Rohner ◽  
Markus Didion ◽  
Anne Herold ◽  
...  
Keyword(s):  
Forest Management ◽  
Timber Harvesting ◽  
Reference Levels ◽  
Management Scenarios ◽  
Individual Tree ◽  
Development Models ◽  
Management Scenario ◽  
Species Mixture ◽  
The Individual ◽  
Business As Usual

Forest development models have been used to predict future harvesting potentials and forest management reference levels under the Kyoto guidelines. This contribution aims at presenting the individual-tree simulator MASSIMO and demonstrating its scope of applications with simulations of two possible forest management reference levels (base or business as usual) in an example application. MASSIMO is a suitable tool to predict timber harvesting potentials and forest management reference levels to assess future carbon budgets of Swiss forests. While the current version of MASSIMO accurately accounts for legacy effects and management scenarios, effects of climate and nitrogen deposition on growth, mortality, and regeneration are not yet included. In addition to including climate sensitivity, the software may be further improved by including effects of species mixture on tree growth and assessing ecosystem service provision based on indicators.

scholarly journals Individual Tree Crown Segmentation and Classification of 13 Tree Species Using Airborne Hyperspectral Data

2018 ◽  
Vol 10 (8) ◽  
pp. 1218 ◽  
Author(s):  
Julia Maschler ◽  
Clement Atzberger ◽  
Markus Immitzer
Keyword(s):  
Random Forest ◽  
Scots Pine ◽  
Tree Species ◽  
Near Infrared ◽  
Mean Shift ◽  
Hyperspectral Data ◽  
Tree Crown ◽  
Individual Tree ◽  
Tree Crowns

Knowledge of the distribution of tree species within a forest is key for multiple economic and ecological applications. This information is traditionally acquired through time-consuming and thereby expensive field work. Our study evaluates the suitability of a visible to near-infrared (VNIR) hyperspectral dataset with a spatial resolution of 0.4 m for the classification of 13 tree species (8 broadleaf, 5 coniferous) on an individual tree crown level in the UNESCO Biosphere Reserve ‘Wienerwald’, a temperate Austrian forest. The study also assesses the automation potential for the delineation of tree crowns using a mean shift segmentation algorithm in order to permit model application over large areas. Object-based Random Forest classification was carried out on variables that were derived from 699 manually delineated as well as automatically segmented reference trees. The models were trained separately for two strata: small and/or conifer stands and high broadleaf forests. The two strata were delineated beforehand using CHM-based tree height and NDVI. The predictor variables encompassed spectral reflectance, vegetation indices, textural metrics and principal components. After feature selection, the overall classification accuracy (OA) of the classification based on manual delineations of the 13 tree species was 91.7% (Cohen’s kappa (κ) = 0.909). The highest user’s and producer’s accuracies were most frequently obtained for Weymouth pine and Scots Pine, while European ash was most often associated with the lowest accuracies. The classification that was based on mean shift segmentation yielded similarly good results (OA = 89.4% κ = 0.883). Based on the automatically segmented trees, the Random Forest models were also applied to the whole study site (1050 ha). The resulting tree map of the study area confirmed a high abundance of European beech (58%) with smaller amounts of oak (6%) and Scots pine (5%). We conclude that highly accurate tree species classifications can be obtained from hyperspectral data covering the visible and near-infrared parts of the electromagnetic spectrum. Our results also indicate a high automation potential of the method, as the results from the automatically segmented tree crowns were similar to those that were obtained for the manually delineated tree crowns.

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