Each year, Heterobasidion spp. is a major cause of economic losses to forestry in the northernhemisphere, including Sweden. New results indicate that pre?commercial thinnings could be at riskfor Heterobasidion spp. infections.

Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.

This report is an assessment of the feasibility of using aerial photographs to estimate number of stems per hectare in young forest stands, used together with upper height to determine the need for pre-commercial thinning or ordinary thinning cutting. Aerial photo-interpretation was conducted in 2007 on assignment of Stora Enso Skog AB. A mean height function based on stand age produced with data from Bergvik Skog AB?s 2006 forest inventory assessment was used as a proxy for upper height and used together with photo-interpreted number of stems per hectare to determine the need for thinning cutting according to Bergvik Skog AB?s definitions. The test area is located north of Falun on Bergvik Skog AB?s land.Flight altitude was approximately 900 m above ground and the aerial photos were taken by L&L Flygbildteknik AB.

Den här uppsatsen grundar sig på två fältstudier i nyutlagda demonstrationsförsök på Asa försökspark som ska användas i utbildningssyfte. Studie 1 bestod av försöksytor i ett 13 år gammalt bestånd som röjts till samma röjningsförband men med tre skilda metoder; motormanuell selektiv röjning, maskinell stråkröjning och som en kombination av bägge metoderna. Syftet var att beskriva det nuvarande tillståndet, simulera fram prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser fram till och med första gallring och jämföra de olika metoderna med varandra. Studie 2 bestod av försöksytor i ett 23 år gammalt eftersatt bestånd där fyra olika åtgärder testades; ingen röjning innan gallring, underröjning i samband med gallring, sen röjning och skogsbränsleuttag. Syftet var även här att jämföra de olika metoderna med varandra genom beskrivning av det nuvarande tillståndet, göra prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser vid första gallring och i den här studien även fram till och med den andra gallringen.

Forest ebeaver is, equipped as a bio-energy harvester, approximately four and a half meter long and weigh just over two tons. The main purpose of this report is to find out whether a small machine like Forest ebeaver can be profitable used in early thinning. To find this out a study has been made using the machine to thin in a young pine stand..

In Korsnäs district Dala Väst there were problems with information concerning their younger forests, mainly those in pre-thinning stage. They were divided into large, heterogeneous stands with often poor stand data quality. In 2006 an aerial photo interpretation of the young forests was conducted to fix these problems. Necessary information to get from the interpretation were silvicultural management suggestions, new stand delineation and new stand data. This thesis is supposed to evaluate the quality and usability of the interpreted data. To evaluate the interpretation an objective control inventory was conducted in 60 stands, either through callipering or counting stems.

A secondary and a pioneer tree species can with advantage be included in a mixed stand to increase the use of sunlight. Nitrogen-fixing plants have been shown to increase the supply of nitrogen in the soil by, for example, litter fall. This deposition acts as a biological fertilization, which may be used by non-fixing plants. Alder is a nitrogen-fixing, pioneer tree species that loses its nitrogen-rich leaves late in the autumn. The aim of this study was to examine the effect on the total volume of production, when different proportions of nitrogen-fixing Alder were part of spruce stands.

Due to soft grounds in combination with seasonal variation in soil humidity, there is a lack of stands that are possible to cut during spring and autumn in some geographical regions. For Holmen Skog this sometimes means that a large proportion of the contracted private forest is cut during the winter when the ground is frozen. One consequence of this is that the proportion of winter stands in the stand bank of own forest increases while spring and autumn stands becomes a scarcity. This in combination with milder winters, especially when there is a long period of reduced bearing capacity in spring or autumn, means that the situation rapidly can become critical. The overall goal with this study was to generate basic data for decision support in the work to achieve a sustainable distribution between own forest and contracted private forest in the stand bank. The study took place at Holmen Skog, district of Umeå, during autumn 2007 and was based on interviews and an analysis of harvest planning and delivery data. The study showed that there is a problem with how the cutting is distributed between own and contracted private forest during the year and that it foremost is the proportion of winter thinning of own forest that has increased in the stand bank.

Water logistics has long been a problem in order to effectively carry out stump treatment in both thinning and final felling. It is important that the stump treatment? equipment is configured as well as a sufficient amount of water is carried out on the harvester to get a cost? effective treatment. The flow control of the equipment has improved and water can be dispensed more efficient, but still the amount of water on the machine is a crucial factor in the total cost estimate. The knowledge of the tools available to bring water as well as the internal logistics of loading and transport to the felling site is deficient. Increased focus on "smart" solutions to manage water cost is of great importance in order to combat Hetrobasidion spp in both thinning and final felling. The purpose of the study is to describe and summarize different solutions of water logistics at stump treatment in final felling.

The main purpose of this M. Sc. thesis is to increase the knowledge about managing urban forestry for recreational use. The analysis is focusing on differences between visitors? experiences in the north and south of Sweden, represented by Nydalasjön and by Härlanda tjärn.

This is a literature review of how the climate change affects the forest growth innorthern Sweden. The temperature will rise about 5 °C with the largest increase in thewinter season (December - February) and the CO2level in the atmosphere is expected tobe doubled. Precipitation patterns will change and increase with 25-35 % and theprecipitation will be in form of rain rather than snow. Today the forests in northernSweden are entirely dominated by coniferous stands. This may shift with the climatechange and results in a larger number of deciduous trees, preferably birch will becomestronger and grow better and faster.

SCA har idag cirka 280 000 hektar beskogad med contortatall (Pinus contorta Dougl. ex Loud. var. latifolia Engelm). Stora delar av den arealen har kommit in i, eller är på väg in i, gallringsbar ålder.

The aim of this study is to describe a number of type stands of lodge pole pine in Norrbotten with respect on stem volume and total biomass. Further questions to answer is if there is stand characteristics that make the stands more suitable for pulpwood in early thinning, or if it is better to apply whole tree harvest. The study shall also give an indication if bio energy can be an economical interesting alternative for Sveaskog. Sampled trees represented the variation in the different stands. Five trees were selected from each stand to represent that stand. Stem volume and biomass (kg dry weight (DW) per hectare) for each fraction was calculated.

The aim of this paper is to study intra household allocation of capital income by using data on Swedish observations. The 1991 tax reform was to change the taxation on capital income from a progressive to a flat tax system. Before the tax reform there were incentives to allocate capital income to the spouses with the lowest income of labor in order to reduce the total tax burden. The data describes the year of 1989 and 1993, those we choose to examine. Using Swedish data from LINDA database we estimate a quotient by ordinary least squares (OLS) regression.

 Syftet med studien är att undersöka samband mellan autistiska drag, emotionell smitta och anknytning i en normalpopulation. 214 personer i åldrarna 18-39, från Örebro och Karlstad universitet, besvarade en enkät bestående av Autism-Spectrum Quotient, Attachment Style Questionnaire och Emotion Contagion Scale. Könsfördelningen var 90 män och 124 kvinnor. Det fanns samband mellan autistiska drag, emotionell smitta och anknytning. Det visade sig att ju starkare autistiska drag, desto mindre mottaglighet för emotionell smitta.