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).

In Sweden and in Scandinavia the amount of tree species are rather few. However many different forms of trees arise due to mutations and gives rare appearances like cut-leaved and hanging forms. In some cases these trees are interesting as cultivars and a few of them have become popular garden trees. The knowledge of the original trees and early propagation is meagre.In this study a selected group of trees were found through search of literature. Eight tree forms were chosen and investigated in situ.

This study investigates three different methods for evaluating MOE,Modulus of Elasticity, in field measurements. The purpose is toinvestigate the possibility to use dynamic measurement methods infield measurements that hitherto (2010) has been performed with staticmethods. The objects of investigation are 20 glulam beams. The firstfield measurement took place in november 2007 and applied a staticmethod based on the standard SS-EN 408. The second measurement,described in this study, took place during summer 2010, and appliedstatic as well as dynamic methods.The MOE of wood is affected by a range different factors.

In the Kolmården area, northeast of Norrköping in south-central Sweden, it was discovered that shoots of spruce Picea abies, plants to a seemingly large extent had been browsed by deer. The area inhabits a dense red deer population, alongside with moose and roe deer, and red deer is thus suspected to cause the damage. The main purposes of this study are, however, to estimate the extent of the shoot-damage and to investigate what factors that may affect the browsing of shoots. For each stand information was recorded about the age of the plants, area for the stand, height over the sea for the stand, site productivity, type of plants and stand-history. The study was done in three areas: Simonstorp, Stavsjö and Valinge. At Simonstorp and Stavsjö, respectively, 10 stands were chosen for study and on Valinge six stands. In each stand, 10 plots were sampled.

Tallen (Pinus Sylvestris L.) är för den svenska skogsindustrin ett av de viktigaste trädslagen. Tallens kvalitet är påverkbar genom röjning, där röjningens intensitet och tidpunkt är avgörande för tallens diametertillväxt, årsringsbredd, kvistdiameter, krongränshöjd, stamform, juvenilvedsandel och elasticitetsmodul. Röjningsarbete utförs via olika röjningsformer, där röjningsformerna enkelställning, toppröjning, stråkröjning och korridorröjning används i svenskt skogsbruk. Studien syftade till att utreda om det fanns signifikanta skillnader i behandlingseffekt på tallens medelhöjd, medeldiameter, kvistdiameter, krongränshöjd, höjd/diameter-kvot, elasticitetsmodul och årsringsbredd mellan röjningsformerna enkelställning, toppröjning, stråkröjning och korridorröjning. Studien syftade även till att utreda om ovanstående röjningsformer hade haft effekt på sambandet mellan elasticitetsmodul och årsringsbredd, i enskilda årsskott.Det studerade försöket anlades år 2003 i tallungskog i Umeå, Västerbottens län.

?Development of Norway spruce, Douglas fir beech and Scots pine with a larch shelter wood? is a report written by Per-Olof Magnusson. The thesis is a compulsory part of forest engineer program at ?Skogsmästarskolan?, SLU, Skinnskatteberg, Sweden. The purpose of this report is to describe and evaluate an experiment with hybrid larch (Larix x eurolepis) as shelter wood, and different tree species growth and survival depending on the density of the shelter wood. The experiment is conducted by southern Swedish forest research centre, faculty of forestry, SLU in Alnarp. The hybrid larch ought to be an interesting alternative to birch (Betula sp.) as shelterwood on suitable sites in southern Sweden.

Since the end of the eighteenth century forest damage caused by the pathogen Gremmeniella abietina has been observed and documented. During the latest epidemic in Sweden more than 480 000 hectares forest land have been injured and this has lead to considerable economic losses. For the pathogen to succeed with infection, spore dispersal and colonization the right environmental conditions is required. The aim of this paper is to describe the diseased stands using site and stand characteristics and to evaluate the effect of these variables on the disease incidence. Further, the thinning performed during the time for spore dispersal and its relationship to injured stands is examined.

Huvudsyftet med denna studie har varit att kalibrera Uustera) ståndortsindex skattat med SIS, vilken är en funktion av ståndortsfaktorer, med avseende på ståndortsindex skattat med SIH, vilken är baserad på den aritmetiska medelhöjden och brösthöjdsåldern för de två grövsta träden på en cirkelprovyta med 10 meters radie. SIH anses vara den metod som ger det mest rättvisande ståndortsindexet, men den kan endast användas då provytan uppfyller en rad krav, medan SIS kan användas överallt Materialet i studien består av insamlat data från Holmen Skogs företagstaxering år 2000. För 700 provytor skattades ståndortsindex med både SIH och SIS. Det insamlade datamaterialet delades därefter in i åtta olika geografiska område, från Norrköping till Lycksele och för de olika trädslagen tall (Pinus sylvestris) och gran (Picea abies). Huvudsyftet med kalibreringen har varit att skatta värdet på SIH givet att man vet värdet på SIS och andra ståndorts- och beståndsegenskaper.

Herbivore impact on the Swedish forest has under a long time been a common subject of debate. There are many different opinions depending on what direction the forest owner has with his/her forest. Populations of moose and roe deer have increased significantly in Sweden during the last decades. The purpose of this study is to get a full picture of the herbivore impact on the regeneration areas. The field work was done once a year for seven years (1999?2005).

Sweden has today the highest moose (Alces alces) population in the world. The population has been very high since the late seventies and in the beginning of the eighties there was a big ?moose explosion?. The main food source for moose during the winter is young pine (Pinus sylvestris) and birch (Betula spp.). The high moose population has therefore lead to high damage on pine forests over big areas.

Wood has always been an important material for people, and it is used for many applications. As for example, fuel for cooking and heating houses, construction materials and for constructing means of transport. Since wood also is a material that with time biologically degrades due to activity by micro organisms and wood fungi it is important to find ways to protect and further lengthen the life span of the material when in service. One method is to decrease the amount of water in the material by impregnation with an hydrophobic oil. The Linotech method which uses only pure linseed oil is one such possible method. The aim of this study was to investigate the possibility to at the same time impregnate and stain/colour wood samples of pine and spruce by using the Linotech method.

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.

A new type of forest tree seedling, called mini seedling, has been developed by the University of Dalarna in Garpenberg, Sweden. Compared to traditional containerized seedlings that are grown for 1 ? 2 years, mini seedlings are grown for only 10 weeks. The mini seedlings are small, easily planted, cost effective, and reduce the amount of chemicals used in the nursery. Research has shown that mini seedlings tend to have higher overall survival rates than traditional container seedlings.

Root rot is a big hurter and a huge economic problem for the Swedish and European forestry. The severest hurter is Heterobasidion annosum (Fr.) Bref and it occurs as two different species in Sweden. Commonly referred to as the P-type (Heterobasidion annosum s.s. (Fr.) Bref.) and the S-type (Heterobasidion parviporum Niemelä & Korhonen). Therefore a lot of research has been carried out in this topic to find a solution and reduce this problem, one alternative that have shown to be profitable is stump treatment in thinnings.

Granbarkborren, Ips typographus, är den mest destruktiva skadeinsekten för svensk barrskog och orsakar årligen stora ekonomiska förluster för landets skogsägare. Granbarkborren kan endast föröka sig i döda träd. För att döda ett stående friskt träd kan de med feromoner signalera till andra granbarkborrar att tillsammans inleda en massattack. Granbarkborren är även beroende av blånadssvampar för att kunna slå ut friska träd. Med dessa blånadssvampar kombinerat med en massattack kan granbarkborren döda trädet inom några veckor.