In today´s forestry, assessments of needs for thinning are based on basal area measurements. This is an indirect measurement. The approach and the developed assessment tables are based on an assumed production forest, which implies that management proposals in stands that deviate from the basic model may be misleading. Since Walter Bitterlich in 1948 launched the idea of the relascope, several modifications have been developed for different purposes. In common is that all are based on a certain angle measurement principle.

Det finns en rad satt att beskriva gallringsformen. Ofta används begreppet gallringskvot i dessa sammanhang utan att närmare ange vilken metod eller definition som använts for att beräkna den. Detta kan lätt leda till att missuppfattningar uppstår. Denna studie belyser olika definitioners känslighet for bland annat beståndsstruktur, gallringsform och stickvägsavstånd. Studien innehåller dessutom en jämforelse mellan olika metoder att mäta och uppskatta gallringskvoten i ett bestånd.

This project was a request of Norrbodal´s Forestry Board, Västra Götaland. It was performed as a qualitative interview analysis of private forest owner?s deficient motivation regarding pre-commercial thinning. The purpose of the project is to investigate what the Forestry Board can do to motivate private forest owners to do more pre-commercial thinning. The results build upon 16 qualitative phone interviews with forest owners that have their forest within the district of Norrbodal. The owners are divided into two groups, the one who have performed the pre-commercial thinning and the one that has possible pre-commercial thinning needs on their properties according to the pre-commercial thinning analysis ,which is the result of a satellite analysis.

In forestry there are always needs of forest data to make good strategic decisions of different actions and economic winning. Usually this data gets from field-estimations made by forest workers with expensive costs and sometimes unsatisfied quality. StoraEnso Skog is a great forest company in Sweden and they have part of the responsibility of the forest own by Bergvik Skog. Bergvik Skog is owner of 1, 9 million hectares productive forest land. Both Bergvik and StoraEnso have great interest in new inventory techniques to get the important forest data. The company Foran Remote Sensing offers the opportunity with airborne laserscanning of forest and forest land. Foran got the mission of Bergvik and StoraEnso to laser scan Bergviks possession in Älvdalen, Dalarna.

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.

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.

The purpose of this study was to estimate the removal of biomass in connection with thinning operations in young stands that are dominated by small diameter trees. The economy of such operations depends on the products generated as well as the performance of the harvesting systems. Conversion tables designed to predict the outcome based on harvesting method was another goal of this study. Removal of biomass affects the nutrient composition of the site. Therefore it is a purpose that this study will provide researchers with some variables that can be utilized when studying this aspect. Trees were harvested and divided into bunches based on diameter.

The purpose of this study was to analyze the two thinning models: Bergvik Skog´s thinning model, which is based on total stems and dominant height, And Swedish forest agency´s thinning model which is based on basal area, habitat index, dominant height and recommended number of stems at final felling in Heureka´s StandWise and PlanWise. The data we chosen for our study were taken from the Swedish National Forest Inventory and we were creating a simulated stand based on a great number of sample plots in Region three from The Swedish National Forest Inventory. We had chosen to create one stand with low habitat index (T20) and one with high habitat index (T24). Our purpose were to come as close as possible to a natural stand in central Sweden. We performed the thinning in StandWise and analyzed the data I Excel files. Our thinning optimizing´s were performed and analyzed in PlanWise. There wasn´t any big differences between the thinning on the lower habitat index.

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.

The fungus Gremmeniella abietina causes damage to conifers that can lead to tree death. In 1999 and 2001 the pathogen caused severe attacks in Sweden, where about 500 000 ha of pine forest were affected. Trees of all ages were attacked, but mainly forests between 30-60 years that were ready for their first commercial thinning. After recommendations from the forest agency, sanitary fellings were made to trees that had more needle loss than 85%, a total of about 50 000 ha. Economic losses have been estimated to more than one billion SEK.

Extensive planting of the tree species lodgepole pine (Pinus contorta var. latifolia) during the 1970s and 80s has resulted in large areas now being available for commercial thinning. However, the varying quality of the stands creates a problem. The purpose of this study was to investigate, at the Torsby district of the Stora Enso forest company, how well the present computer records of the stands correspond to reality and determine which stands are, from a qualitative perspective, suited for timber production. Finding variables that indicate better stands would give Stora Enso the possibility of selecting qualitative stands which are more profitable to thin. The study included 32 stands containing at least 70 % Pinus contorta.

This thesis is about the effects of fertilizing and thinning on furniture timber from redwood. Interviews of furniture manufactures have been made and observing of timber from the Swedish fertilizing and thinning trails. The result from the interviews showed which properties that is important for the furniture manufactures and then the result from the observation showed which type of management of the forest that gave the most timber that had those properties. .

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).

This rapport is about how often private forest owners follow the measures proposed in their forest management plan. The survey is made in cooperation with the forest-owners association Norrskog. The private forest owners are relatively satisfied with the forest management plans and with the measures proposed. There are some differences between those who live on or near their property and those who live many miles away. The forest owners who live on their property are those who follow the proposed measure of precommercial thinning to the largest extent. That group also values precommercially thinned stands higher than thinned stands. The complete opposite is the case for the group that lives far away from their property. Almost all of the respondents thought that the forest management plan would be or had been a good help in the decision making about the forest..

The costs of logging and of transportation with truck are dominating the total cost of wood delivered at industry. To support the profitability for the members' forestry the processing and handling with the timber has to be as efficient as possible. Increased length of pulpwood in thinning is one conduct that can result in higher productivity and/or lower costs. The study is scaled as a system analysis with the aim to exemplify the differences between working with 3- and 4-meter as standard length of pulpwood, related to biological aspects, timber receipts, cost of logging and cost of transportation with truck. Important aspects are if the change is technically and biologically feasible and economically profitable.