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170 Uppsatser om Spruce - Sida 4 av 12

Produktivitet vid stubblyftning :

Stump wood was used between 1850 and 1950 for production of tar and as firewood. In the 1950s the use decreased because of the introduction of the cheap fossil oil. In the 1970s stump wood became an interesting issue again as a raw material for the pulp industry. Stump lifting has today become a possible source for bioenergy. The objectives with this study were to investigate the productivity of stump lifting and stump extraction, and to analyse the economy.

Hur ska tall- och gran bestånd i Götaland gallras för att minska risken för vindskador?

With knowledge of how the southern Swedish forests have been affected by storms the past years, this study intended to find out which factors affect the storm firmness of a stand the most. The study was based on data from stands in the, by the storm Gudrun, affected area. The results of the analyses that tested the stand factors that influence the amount of storm damage to the greatest extent showed that the storm sensitivity of Norway Spruce stands were largely due to previous management actions. The factors that could be controlled by thinning and had relevance of storm damage standpoint, according to the results were; the dominant height, volume, basal area weighted mean diameter and stand age at last thinning. In this study, these results are not as clear for Scots pine.

Röjningsförbandets betydelse för avverkningsekonomin i södra Sverige :

The aim of this work is to demonstrate how the net present value (NPV) at the time of the first thinning depends on the spacing after pre-commercial thinning, and show how net value from first thinning in same stand is influenced. This study is performed with models based on non-distant dependent growth models for single trees. Two different growth models have been used, one for cleaning (pre-commercial thinning) and one for thinning. The first one yields stem density distributed over diameter classes. In the second one, (the thinning model), it is possible to choose when thinning should be done, the thinning method, thinning grade and numbers of thinning.

?dn?ris?: att b?ja st?nger till t?ltk?ta

This thesis is my exploration of the immaterial heritage that is the craft of bending of ?dn?ris? out of Spruce. It?s a broken tradition that is scarcely described, mainly through Yngve Ryd?s report T?ltk?tor (1999) that contains interviews with two knowledge keepers, Nilas Tuolja and Johan Rassa. Yngve Ryd?s report went against the earlier opinion by the mid 20th century ethnologist Ernst Manker who claimed that they were only made exclusively out of mountain birch that has curved growth. As a background, I discuss the special importance of heritage conservation, both material and immaterial, in a S?mi context as being an indigenous people.

Tillväxtreaktion på kvarlämnade träd i Hagners "Naturkultur" försök :

The primary goal of this study was to investigate how the radial growth of retained trees responds after thinning-from-above. The National Board of Forestry which initiated this study, was interested in whether there were differences in the growth-response between the tree species Scots pine (Pinus sylvestris L.) and Norway Spruce (Picea abies (L.) Karst.). Another question of issue was if there were differences in the growth response between trees of different sizes. It is within the framework of the National Board of Forestry?s, Continuous Forests Project that these urgent questions are to be answered.

Factors affecting bark-stripping by red deer (Cervus elaphus) : the importance of landscape structure and forage availability

Bark-stripping by red deer (Cervus elaphus) cause extensive damage to economically valuable Spruce trees (Picea abies) in Swedish forests. The underlying causes for bark-stripping are not fully understood, and the frequency and severity of damage unpredictably differ between regions. In this study, I investigated if landscape structure (e.g. agricultural dominated landscape opposed to forest dominated landscape), forage availability, population density and disturbance (e.g. roads and settlements) affect bark-stripping frequency.

Thuja plicata - etableringsförsök av jättetuja med fyra olika provenienser

Future climate changes may lead to an interest of alternative and foreign forest tree species in order to spread the risks in forestry. Douglas fir, Sitka Spruce, Freemont cottonwood and hybrid aspen are examples of popular foreign tree species that along with western red cedar could have a future in the Swedish forests.Södra Skogsägarna and SLU have collaboration in establishment of foreign species in Swedish forests.The purpose of this study was to analyze and present the establishment of western red cedar, and to survey and illustrate injuries of freeze drying and other damages like deer browsing, vegetation and insect attacks. The study included four different provenances, and Spruce as a reference, planted in two locations ? Asa and Släne.Western red cedar is despite its name a conifer of the cupressaceae family with defined secondary characteristic and gets along well with an overstory. Western red cedar grows often in mixed stands with similar conifers and its natural habitat is within and in the area near to British Columbia.The study included two series of field inventories, one made in the summer and one in the autumn 2013, three growing seasons after plantation.

Fuktkvotens inverkan på oljeupptag och pigmentinträngning i tall (Pinus sylvestris L.) och gran (Picea abies L. Karst) vid impregnering med Linotechmetoden :

Wood has always been an important material for people, and it is used for many applications. As for example, fuel for cooking and heating houses, construction materials and for constructing means of transport. Since wood also is a material that with time biologically degrades due to activity by micro organisms and wood fungi it is important to find ways to protect and further lengthen the life span of the material when in service. One method is to decrease the amount of water in the material by impregnation with an hydrophobic oil. The Linotech method which uses only pure linseed oil is one such possible method. The aim of this study was to investigate the possibility to at the same time impregnate and stain/colour wood samples of pine and Spruce by using the Linotech method.

Kloridhalter i gran utmed en depositionsgradient för havssalter :

The knowledge of the chloride content and its fluxes and patterns in trees is insufficient. Increased knowledge would be desirable, one of many reasons is to be able to more efficiently meet the problems that the substance causes in the pulp industry. The purpose of this study was to examine and describe the chloride concentration of Norwegian Spruce (Picea abies L. Karst.) in the south of Sweden. Furthermore the aim was to be able to predict chloride concentration from readily measurable site factors.

Skötselmetoder för bestånd med produktions- och naturvårdsmål :

This study is made on assignment by the local board of forestry in Skåne, Blekinge and Halland. The change of the forest law 1994 brought a new type of management plan. A more active planning was introduced in order to equate the environment goal with the production goal. The purpose with this study is to give a better picture of how planning for nature conservation in production forest is made and to develop support for selection of silviculture methods for stands with combined goals. With combined goals means production forestry with a reinforced consideration to both nature and culture, called PF-classified stands. This was done by: ? Describing silviculture models from the literature that are possible to use for stands with combined goals. ? Describing silviculture models that is used in practice in stands with combined goals. ? Describing how the classification of stands with combined goals is used. Which means, were in the terrain, with which frequency and in which type of forest PF-classification is used. ? Comparing differences and similarities of theoretical and practical used models. The study was done partly as a literature study and partly as an interview study of forest planners.

Vindfällning, tillväxt och plantuppslag i en 13-årig granskärm i Medelpad :

The interest for alternative forest regeneration methods increased significantly during the 1990´s after 50 years dominance of the clear-cutting system (Holgén & Hånell 2000). One reason for this was that clear-cutting was being more and more questioned by different envi-ronmental organizations and because the forest sector for economical reasons wanted to find cheaper ways to regenerate forests. In the beginning of the 1990´s two shelterwood experi-ments were established in a joint effort by Svenska Cellulosa Aktiebolaget (SCA) and the Dept of Silviculture, Swedish University of Agricultural Sciences (SLU). The experiments include various forms of cutting and shelterwood densities and represent productive Spruce forests in central and north Sweden (Roggsjön in the province of Medelpad and Skikkis-jöberg in the province of Västerbotten, respectively ). The experiment next to Roggsjön has been reported earlier in three MSc theses, and is also the focus of this thesis.

Effekten av metyljasmonat som skydd mot gnag av snytbagge (Hylobius abietis) på gran- och tallplantor :

The effect of methyl jasmonate on resistance against the large pine weevil (Hylobius abietis) in Scots pine and Norway Spruce seedlings. A field experiment was conducted in order to determine the dose-response effects of methyl jasmonate (MJ) on growth and defence to pine weevils in Scots pine (Pinus sylvestris) and Norway Spruce (Picea abies) and to compare the effect of MJ between pine and Spruce. In addition a complementary greenhouse experiment was conducted with the same aims as above and to determine the amount of resin ducts and their correlation to the feeding of pine weevils. The field experiment was conducted on a fresh clear cutting in Garpenberg, southern Dalarna in central Sweden. The experiment consisted of 30 blocks with three kinds of containerized seedlings: 2-year old Spruce, small pine (before shoot elongation) and 1-year old pine (already shoot elongated). They were all exposed to 4 treatments 14 days prior to the experiment: control, 25 mM/L MJ, 50 mM/L MJ and 100 mM/L MJ. Data on weevil damage and seedling growth were collected after the first and the second growing season. The seedlings in the greenhouse experiment were of the same kind and were exposed to the same treatment as the ones in the field experiment.

Beståndsutveckling i stormskadade granbestånd

The storm Gudrun in 2005 led to massive windthow damage in forests in southern Sweden. Since then there has been a growing interest in factors influencing wind damage in above all Norway Spruce (Picea Abies) stands. Although many other interesting areas still need to be examined. In 2005 there where a lot of stands that suffered different degrees of damage, a lot of these stands weren?t cut, but instead left to grow. The future development of these stands is uncertain and the guidelines are unclear.

Karaktärisering av Gremmeniella-skadade bestånd inom Holmen Skog AB :

Since the end of the eighteenth century forest damage caused by the pathogen Gremmeniella abietina has been observed and documented. During the latest epidemic in Sweden more than 480 000 hectares forest land have been injured and this has lead to considerable economic losses. For the pathogen to succeed with infection, spore dispersal and colonization the right environmental conditions is required. The aim of this paper is to describe the diseased stands using site and stand characteristics and to evaluate the effect of these variables on the disease incidence. Further, the thinning performed during the time for spore dispersal and its relationship to injured stands is examined.

Spatt relaterad till tarsalledens vinkel

The effectiveness of Phlebiopsis gigantea to prevent spore infections from Heterobasidionannosum and Heterobasidion parviporum on hybrid larch stumps were investigated in fivestands in southern Sweden. All sites are former forest land and the age of the trees wasbetween 9 and 13 years.The study was implemented in August 2010, a month where spore dispersal should be great.The five sites were located in previously un?thinned monocultures of hybrid larch. The sporeload in the air was studied with the help of spore traps from three different tree species;Norway Spruce, Scots pine and hybrid larch. A total of 146 spore traps, evenly distributed inall five sites were analyzed.

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