Sitka spruce (Picea sitchensis (Bong.) Carr) is just like Norway spruce (Picea abies) a species in thegenus picea. The natural range of Sitka spruce is a narrow strip along the west coast of North America. Itis the most coastal of all picea species, and very dependent on the mild and humid climate along thepacific coast.Sitka spruce has been grown a long time in the countries around the North Sea, particularly in GreatBritain where it currently is the most important species in British forestry. Sitka spruce has not beenplanted in Swedish forests to any large extent before the storm Gudrun in 2005. Several studies indicatethat the production of wood biomass is higher for Sitka spruce compared to Norway spruce.

In Scandinavia, capercaillie are often associated with pine trees (Pinus sylvestris) in winter, with pine needles as the main diet. Few dietary studies have been conducted in Sweden and winter diet is subject to little debate. The interesting thing is that this "pine specialist? is also found in spruce (Picea abies) forest habitats where pine is scarce or unavailable. In many studies outside Sweden (primarily Central Europe) spruce is regularly observed in the winter diet, but I have found no reports on the selection of the diet in spruce forest areas in Sweden.

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

The soil acidification and the pH-value of the soil have been discussed for many years. Many observations of the tree species effects on the soil pH have been done. We have discussed the effects on the soil surface pH-value with a birch (Betula spp. L.) admixture in Norway spruce stands (Picea abies L.).We have used data from the Swedish National Forest Inventory. We have also discussed how the wood production and the biodiversity can be increased in mixed stands, in according to the Swedish forestry act Skogsvårdslagen. Our sampling areas are located in Norrland, Sweden. The results show a significant correlation between an increased birch admixture and an increased pH-value of the soil.

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.

Tree fiber lengths controls properties like strength and smoothness in paper and other wood products. For forest researchers it is of interest to be able to determine the fiber lengths in standing trees. Mo?rling et al. (2003), among others, have developed methods to estimate fiber length distributions in standing trees without damaging them.

Kravet på användning av förnyelsebara energikällor ökar, år 2020 ska de stå för 50 % av all energianvändning. För att öka utbudet av skogsbränsle och utveckla bränslekedjan i hållbar riktning måste ny kunskap och teknik utvecklas för intensivodling av snabbväxande trädslag på skogsmark. Mot denna bakgrund har ett trädslagsförsök anlagts i södra Sverige, med syftet att på sikt besvara frågorna kring intensivodling av skog. Avgången hos plantor är som störst under de första åren efter plantering för att därefter plana ut vid cirka 10 års ålder. Överlevnaden under föryngringsfasen beror i hög grad på vilken utsträckning snytbaggar förekommer samt vilka åtgärder man vidtagit för att få så bra etablering av plantorna som möjligt. Syftet med studien var att undersöka överlevnaden, skador och höjdutvecklingen för de ingående trädslagen tall, gran, björk, hybridasp och poppel, 1 till 2 år efter plantering. Resultatet visade en lägre överlevnad andra året jämfört med första året. Detta berodde delvis på en okänd skada hos poppeln, som troligtvis också hade inverkan på höjdutvecklingen.

Densitetsmätningar och permeabilitetstest enligt EN 927-5 har utförts för att studera huruvida granvirkes fysikaliska egenskaper i kombination med applicerat färgsystem påverkar permeabiliteten. De egenskaper som studerats är frod- och senvuxenhet, splint- och kärnved samt densitet. Aktuella färgsystem som studerats är alkyd, akrylat och linolja, vilka jämförts med omålad referens. Studien påvisar inget samband mellan virkets densitet och permeabilitet, bestruket eller ej. Det som istället tycks påverka vattenabsorptionen är närvaro av splint-/kärnved samt frod-/senvuxenhet.

Syftet med denna studie var att undersöka möjligheten att producera virke av gran som enbart består av kärnved och därmed öka kvaliteten för fasadvirke.För att uppnå syftet har flera olika metoder kombinerats. Metoderna var enkät, analys av data från experiment, simulering och validering.Kärnvedens diameter beror på ålder/antal årsringar och årsringsbredd. Bredare årsringar närmst märgen innebär en större diameter kärnved vid kärnvedsbildningen och en större diameter kärnved vid avverkning.Det är möjligt att producera virke av gran som enbart består av kärnved. Det innebär emellertid att omloppstiderna kan behöva bli längre för att uppnå dimensioner av 120 ? 195 mm breda brädor och reglar.

The aims of the silvicultural method natural regeneration of spruce (Picea abies L. Karst) in birch (Betula pendula and pubescens) shelterwoods are to establish a new stand of tree seedl-ings and to protect those from high groundwater levels, frost damages and grass competition during its first life years. The aim of this work has been to (i) describe how shelterwood and stand characteristics influ-ence the results from using natural regeneration of spruce protected by a shelterwood of birch, and to (ii) compare those regeneration results with planting of spruce after soil scarification in clear-cut areas. Totally 17 harvesting sites have been inventoried and 15 of those included natural regenera-tion in birch shelterwoods, and two were subjects to soil scarification and planting of spruce. The sites represented 7-10 year old final cuts and are located in the coastal (eastern) region of the province of Norrbotten in Sweden. In all areas shelterwood and stand characteristics, as well as the number of main crop seedlings and the height of the highest main crop spruce seedling, were estimated and registered in all areas.

This study was made in an attempt to give the forest research centre Mógilsá a producedtetratherm map and a better understanding of how topography and temperature influencethe growth of two tree species. The digital tetratherm map model, covering the northernpart of Iceland, was developed to investigate the correlation between tetratherm and thegrowth of Picea sitchensis and Larix (sukaczewii + sibirica). The study confirms theusefulness of digital terrain models in providing data for a lot of different factors and forthe tetratherm model. Hopefully will this tetratherm map be used in future studies.Secondly, investigations were made correlating the growth of the two species againsttopographic factors representing height above sea level, distance to the sea, slope andtopex. Thirdly, investigations were made comparing the aspect and the ground shape tothe growth.The growth rate of Larix had strong significant correlations to the tetratherm and thedistance to the sea- factors.

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.

På uppdrag av skogsstyrelsen skall beräkning av framtida potential för uttag av skogsbränsle (GROT) vid slutavverkning av skog göras. Skogsbränsle utgörs till stor del av GROT som är avverkningsrester i form av GRenar Och Toppar. Flera faktorer påverkar hur mycket skogsbränsle det blir vid uttag efter avverkning. Stora snabbväxande träd har en större gren- och barrmassa. I detta arbete har lämplig mark, beståndens ålder och sammansättning selekterats ut med hjälp av GIS för att erhålla största möjliga volym GROT.

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.

Blädningsbruk kan enbart bedrivas med sekundära trädslag i fullskiktade skogar. I Sverige är gran (Picea abies (L.) Karst) det dominerande trädslaget för denna form av skogsskötselsystem. Skötselsystemet har länge varit kontroversiellt på grund av missuppfattningen att det är synonymt med de dimensionshuggningar som i början på 1900-talet härjade de svenska skogarna. Denna studie inriktade sig mot att analysera den volymproduktionsökning som under de senaste 53 åren ägt rum på Siljansfors försökspark, blädningsyta 9082. Data bearbetades och variablerna som huvudsakligen analyserades var diametertillväxt, stamantal samt medelhöjd.