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34 Uppsatser om Contorta - Sida 2 av 3

Picea mariana ((P. Mill.) B.P.S), P. abies (L.), Pinus contorta (Dougl.) och P. sylvestris (L.) : en jämförelse av produktion och potentiell kvalitet hos försöksbestånd i Jämtlands län

Swedish forests are dominated by just two conifer species Norway spruce and Scotch pine. They are not able to achieve the highest possible production or fulfill industry demands for raw materials. The introduction of exotic conifers can potentially meet these shortcomings and present a relevant solution. This study was conducted in a block experiment with ten blocks planted in 1987 by SCA in North Sweden. The objective of the block experiment was to study if Black spruce is an appropriate alternative to Lodgepole pine, Norway spruce and Scotch pine on different site classes.

Utvärdering av produktionsrapporterad volym för contorta

The background to this study is that the forest company, Holmen, has found large discrepancies between harvested volume and the measured volume at the industry. Factors like bark features, breakage, double tops, bends and stem damages was noted, and all stems were measured manually. Hypothesis testing with the method "random in pairs" were used to examine whether the harvester measured values significantly differed from the manually measured. The result of a properly calibrated harvester shows in average underestimation of the volume with Skogforsk Pine as a bark function. This means that the harvester isn´t the reason why the volume measured in the industry is lower, the fault is elsewhere. The study also indicates a need for a unique bark function for logepole pine..

Renens fejskador på tall- och contortaplanteringar inom Malå samebys höst- och vinterbetesområden :

The effects of Reindeer mechanical damages on the planted regeneration of Pinus sylvestris and Pinus Contorta. Semi-domesticated reindeer can damage young trees. In late winter reindeer rub their antlers against young trees. The aim of this study was to quantify those damages. This study covered planted objects from three different areas in northeastern Sweden.

Utvärdering av markberedning och plantering på SCA:s mark i Norrland 1998-2001 : föryngringsresultat efter 10 år

Maskinell markberedning följt av manuell plantering är den vanligaste föryngringsrutinen efter en föryngringsavverkning i Sverige. Många av de forskningsrön som dagens markberednings- och planteringsinstruktioner bygger på är baserade på äldre fältexperiment. Uppföljningar av praktiska föryngringar i fält kan bidra med kompletterande kunskap över vilka svårigheter som finns beroende på ståndort, terrängförhållanden etc. Dessa erfarenheter kan sedan användas till att utvärdera gällande arbetsrutiner och instruktioner. Syftet med detta examensarbete var att utvärdera kvaliteten i det praktiska markberednings- och planteringsarbetet på SCA:s mark i Norrland.

Undersökning av självspridning av contortatallen i norra Sverige

Over the past 40 years 600 000 ha of lodgepole pine (Pinus Contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions. A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.

Uttag av energisortiment vid gallring av contorta, ett komplement till konventionell gallring? :

A recommendation for stand treatment of lodgepole pine (Pinus Contorta) is, in a scientific point of view, lacking when it comes to harvesting for biomass energy. Within the next decades it is expected that 280 000 hectares of lodgepole pine will have reached thinning age on the domains of Svenska Cellulosa Aktiebolaget (SCA). Due to this the interest has grown rapidly for studying the possibilities of harvesting biofuel assortments already in the first thinning. In this study the distribution of the biomass within lodgepole pine trees has been studied and taken into account for estimating the proportions of harvested assortments when using different methods of thinning. The methods studied were conventional biofuel-harvesting (with delimbed branches gathered separately from the round wood) and thinning with cutting of round wood and long tops (incl.

Vindskadefaktorer för tall och contorta-tall på SCA:s marker efter stormen Dagmar

Dagmar är en av de mest förödande stormarna, som med sina 4-5 miljoner kubikmeter vindfälld skog präglat skogssverige det senaste årtiondet. Skogsbolaget SCA förlorade stora mängder skog den 26 december 2011 till följd av stormen. Två av trädslagen på SCA:s marker är tall och Contortatall, med olika förutsättningar vad gäller förmåga att motstå stormvindar. Tillhandahållna data kom från SCA:s inventering före Dagmar, under åren 2007-2011, respektive efter stormen, i februari-mars 2012. Inventerat data har sammanställts, bearbetats och analyserats i Microsoft Office Excel, MiniTab 16 och ArcMap 10.1.

Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper

At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.

Ekonomiska effekter för verkställande av överenskommelser i samråd : en analys av gemensamt nyttjande av skogsmark mellan skogs- och rennäring i norra Sverige

Lavbetesland, med resursen lav i fokus, kan precis som fiskevatten i havet beskrivas som en gemensam resurs, så kallad common pool resources (CPR). Att effektivisera nyttjandet av en CPR leder till att fler kan ta del av den eller att varje part får ut ett högre värde från den. För att kunna maximera effektiviseringen behöver kostnader och intäkter vara kända. Därför är detta examensarbete där jag kartlägger merparten av dessa en viktig del i processen. Lavbeteslandet som CPR nyttjas av både skogsbolag, vilka bedriver skogsskötsel på marken,samt av rennäringen, vilken använder det som betesmark. Skogsbolagens mål med användningen av lavbeteslandet är att maximera volymtillväxten av virke.

Effects of storage time, die channel length and moisture content on pellet quality of lodgepole pine (Pinus contorta Dougl. var. latifolia)

The use of renewable resources is rapidly increasing in Sweden, especially the use of fuel pellets. Through pelletizing the energy content per volume unit is greatly increased and the pellets are more homogeneous with regard to moisture content, particle size and density compared to unrefined fuels like forest residues and chips. For further development of the Swedish pellet industry, the use of different assortments from lodgepole pine (Pinus Contorta Dougl. var. latifolia) is of particular interest, mainly because of its high volume production.

Contortatallens odlingsvärde i Götaland

The third most common conifer in Sweden is Pinus Contorta (lodgepole pine). It originates from the western part of North America and was brought here in the end of the 1920s. The lodgepole pine is today allowed for commercial plantations in central and northern Sweden, excluding high altitude locations. Since 1979 only plantations with scientific purpose are allowed in south-central and south Sweden. This document is focused on how lodgepole pine manage perform compared with Pinus sylvestris (Scots pine) in the southernmost part of Sweden, Götaland. The idea came from the fact that the Swedish government is evaluating a notification from the National Forest Agency that suggests lodgepole pine to be allowed for commercial plantation even in southern Sweden.

Contortatallens roll för virkesförsörjningen på Holmen Skog, Region Iggesund : konsekvensanalys av fyra hushållningsstrategier för contortatall

Large areas of Lodgepole pine (Pinus Contorta var. latifolia) were planted in the 1970s - and '80s. The purpose of the fast-growing species was to increase growth and with short rotation periods allow a rapidly increased harvest level. Today a large proportion of the young forests owned by Holmen Skog, Iggesund are covered by Lodgepole pine and an active forest management is required to spread the harvested volume over time which is desirable by a market perspective. The purpose of this essay is to investigate the possibility of spreading the harvested volume of Lodgepole pine over time.

Från gles skog och brokiga ungskogar till homogen produktionsskog : en skogshistorisk studie av Hällforsmarken under 1900-talet

The forest in the northern part of Sweden has changed dramatically during the last centuries. The forest has gone through a large-scale transformation, from it being only used locally for domestic purposes to becoming very important raw material for Sweden in the industrial age. The strategy by foresters during the second half of the 20th century has been to create pure production forests for commercial forestry. This has mainly succeeded and we have today homogenous production forests that give a high profit to the owners. The aim of the study is to compare the state of the forest in the former state forest Hällforsmarken in the years 1925 and 2000 and to interpret the changes which has taken place.

Site preparation, planting position and planting stock effects on long-term survival, growth and stem form properties of Pinus contorta on southern Iceland

In order to evaluate different afforestation methods for exposed heath lands a field experiment was established in Mosfell on southern Iceland in 1989. The trial comprised six different site preparation methods (control, herbicide application, tree shelters, patch scarification, TTS trenching and mounding). In total 960 container seedlings (1+0) and 960 Nisula roll transplants (2+1) of lodgepole pine were planted. Various planting positions (furrow, hinge, no site preparation (control) and on top of mounds) were tested within the site preparation treatments. This study involves renewed measurements and analyses of the trial.After 19 years the overall survival was 51,7 %.

Lodgepole pine - stability after thinning

SCA has today almost 300 000 hectares of their forest land planted with lodgepole pine(Pinus Contorta var. latifolia). Due to initial extensive planting in the 1970ies the area oflodgepole pine forests in the thinning age has grown rapidly from the end of the 1990ies.During the years 1996-2005 first commercial thinning of lodgepole pine at SCA took place.The goal of the hereby presented study was to investigate the growth and stability in thosefirstly-thinned lodgepole pine stands a few years after thinning. Furthermore, the objectivewas to investigate the relationship between stand stability and different stand parameters.Additionally, lodgepole pine stem quality was estimated.The study is mainly based on the data collected during an inventory project carried out atSCA in 2008. Altogether 91 lodgepole pine stands in northern Sweden were measured afterthe first thinning.

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