The main purpose of this study is to investigate how to reduce the high, and every decade raising, pre-clearance cost. The pre-clearance is today carried out with a brush saw and paid per labour hour. All small trees not suitable for pulpwood are removed to simplify the later work of the Harvester. The study compares the economic results from thinning of four parcels each treated differently regarding harsh or light pre-clearance and extraction of only pulpwood, or both pulpwood and fuel wood. In this type of spruce stand the study indicates that a lighter pre-clearance, followed up with both pulpwood and a fuel wood extraction, has a much better economy than the traditional method of hard pre-clearance and only pulpwood extraction..

Earlier attempts at mechanising pre-commercial thinning have been met with varying degrees of success. Most attempts have been based on techniques where residual stems are straddled. Early treatment is essential to limit damage on residual trees. One part of the present study is an evaluation of mechanised pre-commercial thinning using the new Vimek 404R. Vimek 404R is a fairly small machine that permits selective removal of stems, making it potentially suitable also for areas overdue for pre-commercial thinning. The study established the level of performance for the machine, as well as the improvement needed to make it an economically viable option.

This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers, SLU. The work was an assignment from Södra Skogsägarna and the aim of the work was to investigate the economical and biological output after mechanical planting with Eco-Planter compared with traditional manual planting. Eco-Planter is a tool for mechanized planting, fixed at the end of the boom on a conventional Harvester. The study confirms that manual planting is less expensive under normal conditions. However, the differences between mechanized and manual planting are not that big and with technical development and/or increased labor costs together with an improved work organization the system with Eco-Planter could be competitive. The biological output, e.g. planting result and survival rate, seems to be quite good.

Detta examensarbete har gjorts på uppdrag av SP Maskiner AB och berör längdmätningsenheten på skördaraggregatet SP451LF. Pulsgivaren i den befintliga längdmätningen anses inte nå en acceptabel livslängd och därför skall ett sensorlager prövas som ersättare.Uppdraget består i att söka ett lämpligt sensorlager, dimensionera en komplett mäthjulslagring samt att ta fram ett konstruktionsförslag till prototyp på längdmätning.Arbetet begränsas av att den omkonstruerade längdmätningen skall passa på SP451LF aggregatet. Det betyder att längdmätningens infästning mot aggregatet inte får förändras och dess yttermått måste hållas inom de gränser som aggregatets chassi tillåter..

Formulation and testing of a new type of chainsaw lubricantThe company Agro Oil has come up with the idea of developing an environmentally adapted chainsaw lubricant with a new unusual base fluid. A field test with a tree-Harvester shows unsatisfactory low temperature properties and high wear. In this work the viscosity, price and pour point of different combinations of the given base fluid and three other base fluids have been investigated. Desired viscosity and price are determined for different formulations. The new lubricants tested show lower pour points than almost all products on the Swedish market.A test equipment has been developed to investigate the wear.

The cost of forwarding corresponds to about one tenth of the forestry industries raw material cost. This gives a motive to do good follow-ups to get a good overview of the forwarding distance and, thus, enable improvements. Follow-ups are also justified by the possibility to make more accurate calculations of the harvesting costs, if better estimations of forwarding distance are achieved. Today (2009) Stora Enso has GPS and vehicle-computers in most of their forwarders. These are used mainly for the forwarder to follow the tracks of the Harvester and for the planning leader to see how the forwarder has been driving within the stand.

During the autumn 2009, a 15 hp degree project was accomplished. The objective of the study was to describe different equipment alternatives, suitable for fresh market apple harvest. A field study was conducted during the harvest period to evaluate the efficiency (kg / person/ hour), using the different equipment. Four different systems are described in the study; Pick-ing-bag, Picking-train, Pluk-O-Trak and the Conveyor Harvester. The information about the systems is based on interviews with growers together with previous studies.

Detta examensarbete har gjorts på uppdrag av Rottne Industri AB och berör matarhjulens dubbinträngning i virket. Matarhjulen sitter monterade i skördaraggregatet i skördaren, en skogsmaskin som används vid skogsavverkning. Då inträngningen, som uppstår av dubbarna på matarhjulen, är för stor (>5mm) bildas skador på virket vilket är ett utbrett problem inom skogsmaskinindustrin. Studien kartlägger de vanligaste dubbmönstrens skadeåverkan under kontrollerade och vetenskapliga förhållanden där testerna är designade för att efterlikna verklig skogsavverkning.I studien utförs två tester. Det första visar sambandet mellan presskraft och inskjutningsmått för respektive dubbmönster.

Syftet med detta examensarbete är att sammanställa maskinkostnader för etableringsmetoderna plöjningsfritt och konventionellt. Vi vill även titta på hur stor kapacitet som behövs på maskinparken för den tänkta gården på 600 ha åker, detta för att hinna etablera grödan inom ett rimligt tidsspektra. Anledningen till att vi valt ett företag på 600 ha är att det är den areal tröskan klarar av att avverka inom rimlig tid. Det medför att vi måste ta en del hänsyn till lägligheten och hur mycket av tiden som är så kallat ?tjänligt väder?.

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 aim for the study was to examine a harwarder´s (combined Harvester-forwarder) productivity when harvesting forest fuel in first thinning stands that contains Lodgepole pine and calculate the economy of the harvesting work and estimate the quality of the thinning . The field study area where located near Arvån, about 15 kilometres south ?east from the city of Lycksele. The field studies were taken place in three different stands. All tree stands had the same tree age, but the tree species combination and the density varied.

This Master thesis is performed at the request of the forest company Mellanskog and the local municipality of Borlänge in Sweden and aims to establish recreational adjusted forest management plan for the areas of Mellsta and Skräddarbacken in Borlänge. In all types of urban forestry it is very important that the management plan are accepted by the general public. To make sure that also these plans of future measures, pass in the public, interview studies have been performed in which the public wishes and interests have been examined and applied in the management plan. To make sure that future measures in the forest may be accepted by the public when the forest Harvester enters the woods, it is very important that a well functional work of information has been made. The people living close by the forest shall have been informed a couple of weeks before the time of measures and it must also be good information available that explains what is to be done and why.

To guarantee the customers a job satisfactory executed Sydved has been certified by the ISO 14001 standard. One part of the certification is the standards of soil damages. The soil damages were over represented during 1999 and 2000. It was therefore a need to study the problem in order to see what could be done to reduces these damages. A filed study was carried out on 21 subjectively selected stands from the following five districts: Vänersborg, Falköping, Borås, Jönköping and Åseda. As the study is a descriptive study of the soil damages, their character and extension, only stands were tracks were reported were considered.

In an attempt to prevent ground damage and to reduce harvesting costs, StoraEnso's districts Värmbodal and Fryken, selected a number of final felling areas where the base roads have been marked by planners in the districts. The parties involved in the experiment are mainly planners, Harvester operators and forwarder operators. The purpose of this paper is to determine the findings of this trial and to find cost savings or lost revenue. This has been done with a sample of interviews from the involved parties who logged the chosen felling areas. Literature about the interview process has been used to facilitate data collection, interpretation and analysis of the material. If we look at profitability based on assumed income and expenditure, revenue per MWh would be 63 SEK.

Gallring är en beståndsvårdande utglesning där gagnvirke tillvaratas. Syftet med gallring är att styra över produktionen på ett lägre antal stammar och på sikt skapa ett bestånd med en högre medelstamsvolym än om gallring inte genomförts. Gallring kan utföras enligt olika former, vilket påverkar produktiviteten i drivningsarbetet och beståndets karaktär efter utförd åtgärd. I vissa bestånd kan det finnas ett undre skikt av löv eller gran som försvårar gallringen, så kallad försvårande underväxt. Den här studien syftade till att undersöka om underväxtröjning är en åtgärd som kan leda till att minska kostnaderna i gallring i bestånd med underväxt. En tidsstudie utfördes i två talldominerade bestånd med lövdominerad underväxt i 2-3 meters höjd.