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.

The aim of this study was to evaluate different types of volume and taper equations that can be used to predict single-tree stem volume and stem diameter at any given height along the tree stem for plantation grown Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst) and White spruce (Picea glauca (Mounch) Voss) in Iceland. A number of published tree volume equations were tested and modified to predict the total stem volumes over bark but three logarithmic equations were taken for more in-depth analysis. Three taper equations were tested. Two variable-exponent equations (Kozak 1997, Kozak 2004) and one exponential equation described by Biging (1984). Data from a total of 617 sample trees were used in this study, collected from stands in various parts of the country and present different types of stands growing in different soil types and cover most of the site conditions suitable for forestry in Iceland.

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.

In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.

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.

Wind damages next to strip roads in 1st and 2nd thinning in Boxholm, Östergötland Anneli Fransson, SLU, inst f sydsvensk skogsvetenskap, Examensarbete no 108 Wind damage is something we are all familiar with since the storms Gudrun (2005) and Per (2007). Research about strip roads and wind damage is very limited. It is commonly known that the trees next to the strip roads more often fall whit heavy winds, and the purpose of this thesis was to verify this statement. Data was collected from first- and second thinnings at Boxholms Skogar AB, Östergötland. In first thinnings data was collected from both spruce and pine stands and second thinnings only data from spruce stands was collected.

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.

Sitka spruce (Picea sitchensis) is a tree species that have its natural distribution along the West Coast of North America, from Alaska in the north to northern California in the south. Sitka spruce is a typical coastal tree species that can reach heights up to 85 meters and occurs in single pure as well as in mixed stands. The main purposes of this study were to describe the Sitka spruce growing characteristics and the volume production in comparison to spruce (Picea abies). The possibility to predict future volume production by using prognosis tools designed to be used on spruce were also studied. The material that has been used in this study are permanent sitka trials established by the Faculty of Forestry fixed Sitka trials and also material gathered in this study. A literature study was also carried out in order to determine the Sitka spruce growing characteristics. Sitka spruce has a high adaptation and a high volume production on a broad scale of soil types. The tree species is a pioneer species that has a fast early growth and in combination with sharp needles it is less susceptible to animal browsing than spruce. The factor that is the single most limiting factor for where the Sitka spruce can be planted is frost. This factor can be limited by using plant material with a well-suited provenance. According to the literature, the Sitka spruce has an average total volume production that is between 20-40% higher than spruce.

Different methods for shelterwood cutting have been used in differ-ent parts of Europe since the middle ages. The use of shelter wood cutting in Norway spruce (Picea abies (L.) Karst.) forests in Sweden met a revival in the early 1990s as an alternative for the dominating clear-cutting system when silvicultural costs increased dramatically for the latter. Shelterwood cutting systems involve some possible problems but also a lot of positive effects. Among the problems are increased risk of wind throw and damage of the remaining shelter trees caused by the cutting operation. Positive effects are for example a valuable growth in the remaining trees and increased biological di-versity. This study is based on a total of 79 trees from 4 different treatments in a spruce shelterwood, cut in 1994, in the middle of Sweden (62,4º N).

Stump biomass is energy rich and stump harvesting for use as fuel become more and more interesting in Sweden. Swedish Forest Agency (2009) has estimated that stump harvesting in Sweden would respond to an annual energy supply of 57 TWh/year. However, stump has not been recognized as a bioenergy resource in Sweden. Suitable methods for pre-treatment of stump are probably of great importance to make it accepted as fuel. It is therefore rewarding to carry out an investigation in this area for stump. This report represents results from a diploma project, which was aimed to develop a fixed bed reactor for experimental study of biomass torrefaction, followed by TG analysis and kinetic modelling employing Ozawa method and different kinetic models including one-step and three-pseudo-component models.

The aim of the study was to compare how the population of pine (Pinus sylvestris) and spruce (Picea abies) have changed between 1927 and 2013 in the oak landscape south of Linköping. A field study was carried out in 22 two kilometre lines which also had been studied in 1927. In these lines, which where ten meters broad and had a direction from west to east, the pines and spruces were counted, measured and classified by steam diameter. The obtained result was that the basal steam area (m²/ha) had increased for pine (44%) and spruce (57%) between 1927 and 2013. The amount of trees had increased in all diameter classes except thinner pine and spruce with a diameter of 5-10cm.

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.

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.

Birch is the dominant deciduous tree species in Sweden but only 16 % is found in pure birch stands. The majority of the birch (51 %) is to be found in conifer dominated stands. Swedish forest land comprises approximately of 23 % mixed stands and one problem is that for mixed stands there are few management recommendations. The underlying aim of this thesis was to study the management of mixed forest stands of spruce and birch to achieve good timber quality of birch. The study was based on a literature study and measurement in a field experiment launched in 1998 by the Swedish University of Agricultural Sciences (SLU).

After the two big hurricanes called ?Gudrun? (2005) and ?Per? (2007) in the south of Sweden, some landowners planted Douglas fir instead of the traditional Norway spruce and Scots pine. They did it for different reasons. Some of them spreading their "risk", others because they wanted better growth or to obtain a more storm-resistant stand and trees more protected against rot. In this study, survival and growth were examined on Douglas fir in 21 different locations, owned by private landowners in southern Sweden.