Productivity and profitability of harvesting power line corridors for bioenergy

Effect of multi-tree handling and tree-size on harvester performance in small-diameter hardwood thinnings Erber G., Holzleitner F., Kastner M., Stampfer K. (2016). Effect of multi-tree handling and tree-size on harvester performance in small-diameter hardwood thinnings. Silva Fennica vol. 50 no. 1 article id 1428. 17p. Highlights• Harvesting with the accumulating energy wood head EF28 was studied under small tree dimension (8 dm³) in hardwood thinnings.• Reasonable productivity was achieved.• Maximum achieved cutting diameter in hornbeam stand was 23 cm and 15% lower than in softwood stands.• Head has potential under such conditions. AbstractEarly thinnings are laborious and costly. Thus forest companies are searching for cost and time efficient ways to carry out this task. The study's purpose was to determine the productivity of the EF28 accumulating energy wood harvesting head in harvesting small-diameter hornbeam (Carpinus betulus L.) undergrowth trees and evaluate the effect of its multi-tree handling (MTH) capacity on time consumption. The harvester was a wheeled, three-axle Komatsu 911. A time study of 7.1 hours on 19 plots, with a total area of 0.76 ha was conducted. On average, the harvested tree volume was 8 dm³ and the stand density was 2666 trees/ha. The productivity was modelled with MTH conduction, mean diameter at breast height and the number of trees handled per cycle as independent variables. On average, MTH took 27% longer per cycle, increased extracted volume per cycle by 33% and consequently increased productivity with 5.0%. In 71.9% of the cycles more than one tree was handled and if so, dimensions were smaller than in single-tree handling (5.8 cm vs. 12.0 cm). Maximum felling diameter of 23 cm was about 15% smaller than in softwood (according to the manufacturer's specifications) and the driver didn't exploit the EF28's theoretical potential in terms of trees handled per cycle. It can be concluded that the head could significantly improve productivity in small-diameter wood procurement.

Section: Introductionmentioning

confidence: 99%

“…and birch (Betula spp.) Eberhardinger 2007;Belbo 2010;Lehtimäki and Nurmi 2011;Rieppo and Mutikainen 2011;Di Fulvio and Bergström 2013;Laitila and Väätäinen 2013;Fernandez-Lacruz et al 2013;Bergström and Di Fulvio 2014). Conversely, studies of broad leaf trees, especially hardwood species, have not been of major interest this far.…”

Section: Introductionmentioning

confidence: 99%

Effect of multi-tree handling and tree-size on harvester performance in small-diameter hardwood thinnings

Erber¹,

Holzleitner²,

Kastner³

et al. 2016

“…Consequently, clearing is needed before soil preparation and stand regeneration. For the time consumption of clearing, we used the model of Fernandez-Lacruz et al (2013). We used the unit cost of 35 € h -1 both for precommercial thinning and clearing.…”

Section: Estimating Incomes Costs and Financial Performancementioning

confidence: 99%

“…Even if the sawn-timber yield may be low in birch-dominated peatland forests (Koivisto 1959;Fries 1964;Braastad 1967;Verkasalo 1997;Hynynen et al 2010), the yield of pulpwood and especially biomass for energy can be notable. Profitable management of these stands calls for appropriate harvesting procedures (Fernandez-Lacruz et al 2013;Jylhä and Bergström 2016), for which up-to-date guidelines are currently lacking.…”

Section: Introductionmentioning

confidence: 99%

From useless thickets to valuable resource? – Financial performance of downy birch management on drained peatlands

Niemistö¹,

Kojola²,

Ahtikoski³

et al. 2017

Highlights• The most profitable management regimes for pulpwood and energy wood production in dense downy birch stands on drained peatlands include no thinnings, but final cutting at the stand age of 40-45 years as whole-tree harvesting, or as integrated harvesting of pulpwood and delimbed energy wood stems about 10 years later depending on applicable harvesting method.• A competitive management regime is early precommercial thinning at 4 m dominant height to a density of 2500 stems per hectare and production of pulpwood with a rotation of 55-65 years. Equal profitability is achieved with or without traditional first thinning, which can thus be included for other reasons, for example to improve regeneration of spruce. AbstractDowny birch (Betula pubescens Ehrh.) stands on drained peatlands are often considered useless because they typically do not yield good-quality sawn timber. However, covering an area of ca. 0.5 million hectares and with total yields of up to 250 m 3 ha -1 , downy birch stands on peatlands in Finland have a potential for pulpwood and/or energy wood production. We examined the financial performance of alternative management regimes (with or without thinnings, different thinning intensities, several rotation lengths) combined with alternative harvesting methods (pulpwood, energy wood, or integrated, energy wood being delimbed stems or whole trees). We used data from 19 experimental stands, monitored for 20-30 years. For harvesting removals we considered both actual thinning removals and final-cutting removals with alternative timings that were based on the monitoring data. We assessed the profitability as a combination of the net present value of the birch generation and the bare land value of future generations of Norway spruce (Picea abies (L.) Karst.). The most profitable management was growing without thinnings until wholetree final cutting at the stand age of 40-45 years with an advanced multi-tree harvesting method. In contrast, the standard method in whole-tree final cutting resulted in the lowest profitability, and an integrated method with the energy wood as delimbed stems was the best of the standard methods. Thinnings were unprofitable especially when aiming to produce energy wood, whereas aiming for pulpwood, light precommercial thinning was competitive. Commercial thinning at the traditional "pulpwood stage" had little effect on profitability. The best stand age for final cutting was 40-65 years -earlier for very dense stands and whole-tree energy wood harvesting with advanced method, later for precommercially thinned stands and pulpwood harvesting.

“…and the edges of fields, roads, ditches, railways, power line corridors, etc., referred to collectively as marginal land . Such marginal stands sometimes have similar characteristics to BDTF on conventional forest land, and could therefore be harvested using similar technology, as shown by Fernandez-Lacruz et al (2013), Bergström et al (2015) and Jylhä et al (2015). However, suitable harvesting technology and working methods must be identified for each marginal land type and set of conditions.…”

Section: Introductionmentioning

confidence: 99%

Distribution, characteristics and potential of biomass-dense thinning forests in Sweden

Fernandez-Lacruz¹,

Fulvio²,

Athanassiadis³

et al. 2015

Self Cite

• Biomass-dense thinning forests (BDTF) cover 2.1-9.8 M ha in Sweden, which represents 9-44% of the country's productive forest land area, depending on the constraints applied.• 65% of BDTF area is found in northern Sweden.• Analyses revealed a yearly harvesting potential of at least 4.3 M OD t of undelimbed whole trees (3.0 M OD t of delimbed stemwood including tops). AbstractUnderstanding the characteristics of unutilized biomass resources, such as small-diameter trees from biomass-dense thinning forests (BDTF) (non-commercially-thinned forests), can provide important information for developing a bio-based economy. The aim of this study was to describe the areal distribution, characteristics (biomass of growing stock, tree height, etc.) and harvesting potential of BDTF in Sweden. A national forest inventory plot dataset was imported into a geographical information system and plots containing BDTF were selected by applying increasingly stringent constraints. Results show that, depending on the constraints applied, BDTF covers 9-44% (2.1-9.8 M ha) of the productive forest land area, and contains 7-34% of the total growing stock (119-564 M OD t), with an average biomass density of 57 OD t ha -1 . Of the total BDTF area, 65% is located in northern Sweden and 2% corresponds to set-aside farmlands. Comparisons with a study from 2008 indicate that BDTF area has increased by at least 4% (about 102 000 ha), in line with general trends for Sweden and Europe. Analyses revealed that the technical harvesting potential of delimbed stemwood (over bark, including tops) from BDTF ranges from 3.0 to 6.1 M OD t yr -1 (7.5 to 15.1 M m 3 yr -1 ), while the potential of whole-tree harvesting ranges from 4.3 to 8.7 M OD t yr -1 (10.2 to 20.6 M m 3 yr -1 ) depending on the scenario considered. However, further technological developments of the harvest and supply systems are needed to utilize the full potential of BDTF.