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259 Uppsatser om Scots pine (Pinus sylvestris) - Sida 8 av 18

Förslag till skötselplan för Uppsala högar och Tunåsen : ett exempel på medbestämmande planering

This Master thesis is made at the request of the local municipality of Uppsala in Sweden. The purpose of this work is to create a guiding management plan. Recreation, conservation of the cultivated landscape and the historical environment, conservation biology and the aim of the landowners are all considerd. The area is almost 34 hectares and located north of the centre of Uppsala. Landowners are the National Heritage Board, the diocese of Uppsala, the university of Uppsala, the local municipality of Uppsala and one private landowner.

Vegetationsutveckling och mänsklig aktivitet under äldre Stenålder vid Döudden, Arjeplog kommun :

The landscape in the interior of Norrland has undergone dramatic changes since the deglaciation as a consequence of faultings, earthquakes and tilting of the landscape westwards. Archaeological investigations along former shorelines by the use of models of isostatic land uplift, have revealed many Mesolitic settlements in northern Sweden. Döudden, in the county of Arjeplog, has been investigated by archaeologists that identified settlements from 5200 BC. The objective of this study was to analyse the history of the vegetation and if the vegetation showed traces of human activity during early Holocene, by pollen analysis. The results indicate that the area had an established vegetation c.

Skötselns och ståndortens betydelse för kärnvedsbildningen i tall

Heartwood has always been a desirable part of the tree, due to it?s superior decay qualities com-pared to the sapwood. How the formation of heartwood works has been known for a long time, but which factors that initiates and stimulates the production are poorly understood. This case study presents the results of a study in which silvicultural treatments and site properties had a key position as factors to the formation of heartwood. According to the hypothesis the amount of sapwood is directly controlled by the size of the crown.

Tillväxt, överlevnad och skador för provenienser av Banksianatall (Pinus banksiana, Lamb.) i norra Sverige

Främmande trädslag har i modern tid intresserat skogsbruket i sin jakt på ökad produktion, minskad känslighet för skador, förbättrad anpassning med mera. Ett tidigare oprövat trädslag var banksianatallen (Pinus banksiana, Lamb.), en nordlig, välspridd, pionjär från Kanadas inland med en utpräglad etableringsstrategi för torra, nybrända sandjordar. Studiens övergripande syfte var att utvärdera utfallet från 22 år gamla försök av banksianatall och analysera banksianatallens odlingsvärde i norra Sverige genom att på fem lokaler jämföra överlevnad, tillväxt och skador med tall (Pinus sylvestris L.), contortatall (Pinus contorta var. latifolia Engelmann) och hybriden mellan contortatall och banksianatall. Ett ytterligare syfte var att utreda eventuella effekter av odlingslokalens temperatursumma och trädens latitudförflyttning från ursprungslatituden. I metoden har fältförsök använts där varje enskilt träd mätts och bedömts. Materialet var insamlat i naturbestånd i nordvästra Kanada från 12 provenienser med en latitudinell spridning av cirka fem breddgrader.

Site preparation, planting position and planting stock effects on long-term survival, growth and stem form properties of Pinus contorta on southern Iceland

In order to evaluate different afforestation methods for exposed heath lands a field experiment was established in Mosfell on southern Iceland in 1989. The trial comprised six different site preparation methods (control, herbicide application, tree shelters, patch scarification, TTS trenching and mounding). In total 960 container seedlings (1+0) and 960 Nisula roll transplants (2+1) of lodgepole pine were planted. Various planting positions (furrow, hinge, no site preparation (control) and on top of mounds) were tested within the site preparation treatments. This study involves renewed measurements and analyses of the trial.After 19 years the overall survival was 51,7 %.

Överlevnad och tillväxt för nyplantersade barrots- och täckrotsplantor : en studie av 42 bestånd i södra Sverige

The choice between bare-rooted and containerized seedlings in southern Sweden affects the investment costs as well as growth and survival. It is important to take these differences into account when choosing seedling type for reforestation. The most important differences between the two seedling-types is that bare-rooted seedlings has open root systems whereas the roots of containerized seedlings are grown in a container which may contain water and nutrients that are available for the seedling during the first period after planting. Moreover, bare-rooted seedlings are often older which results in thicker stembase and better resistance to attacks of pine-weevil (Hylobius abietis). In order to study differences in survival and growth between bare-rooted and containerized seedlings a survey study of newly planted clearcuts in south-western Sweden was made. In the study tree seedling types was included, one bare-rooted and two containerized with different ages. The population of pine weevils was probably low during the studied period which resulted in lower pine-weevil damage than normally found in this area.

Björkbarksextrakt, BBE : en lönsam lösning på betningsproblematiken?

The calculations in this thesis are evaluating the profit as a consequence from treating young stands of pine in Sweden with birch bark extract, BBE. Treatment is to be done with the object to lower or fully reduce the moose browsing on pine. The study is made in three versions. The results from each version separately will follow below. Version I.: The size of the moose population is in no way affected by the reduced resources of food as a consequence of large scale treatment with BBE on pine. Results show profit at a 3 percent level of interest with the exception of treatment program with more than 4 treatments all together and with the exception of Västerbottens Län with an early first treatment. Version II.: The population of moose decrease from 10 to 5 individuals per 1000 ha as a consequence from large scale treatment with BBE on young pine stands.

Hur mycket frö sprids från Pinus contorta? : kottproduktion, serotinitet och frökvalitet i relation till beståndsålder i södra Norrland

Contortatall (Pinus contorta ssp. latifolia) började planteras storskaligt i Sverige runt år 1970 men det dröjde till 1987 förrän Sverige lagstiftade begränsningar för hur den fick användas i skogsbruket. Detta gjordes bland annat på grund av att det saknades information om dess spridningsförmåga. Contortans spridningsförmåga i Sverige är fortfarande okänd och lagstiftningen är densamma. För att kunna beräkna spridningsförmågan och i förlängningen den potentiella etableringsframgången behövs kännedom om contortans fröproduktion i Sverige.

Sticklingsförökning av frilandsrosor : praktisk studie av sticklingstidpunktens och sticklingspositionens inverkan på rotningen av ledsticklingar

This essay begins with a literature study of the different propagation methods for roses, and a survey of the factors affecting the rooting of cuttings in general and rose cuttings in particular. The main part of the essay consists of a practical study of the rooting of rose cuttings. I have chosen to examine how the time of year when the cuttings are taken, and the position of the cuttings influence the rooting. Three different cultivars were used as mother plants; ?Maria Lisa? and two Burnet roses; ?King of Scots? and ?Poppius?. The mother plants were container grown ?King of Scots? and ?Maria Lisa?, and outdoor grown ?Poppius? and ?Maria Lisa?.

Gallringsprioritering av contortabestånd :

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.

Utvärdering av produktionsrapporterad volym för contorta

The background to this study is that the forest company, Holmen, has found large discrepancies between harvested volume and the measured volume at the industry. Factors like bark features, breakage, double tops, bends and stem damages was noted, and all stems were measured manually. Hypothesis testing with the method "random in pairs" were used to examine whether the harvester measured values significantly differed from the manually measured. The result of a properly calibrated harvester shows in average underestimation of the volume with Skogforsk Pine as a bark function. This means that the harvester isn´t the reason why the volume measured in the industry is lower, the fault is elsewhere. The study also indicates a need for a unique bark function for logepole pine..

Gremmeniella abietina-epidemin 2001 : har skogen återhämtat sig?

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.

Fältskiktsvegetationen 30 år efter beståndsanläggning : effekter av olika nivå på skogsskötselintensitet

En landsomfattande försökserie anlades mellan 1984 - 1988 med 15 försöksblock i Sverige. Syftet var att studera den totala effekten på virkesproduktionen av tre olika intensiva skogsskötselalternativ. Inom varje block upprättades en extensiv behandling som innebar att ingen åtgärd efter avverkning vidtogs, en normal behandling som motsvarade markägarens normala skötselintensitet vid tiden när försöken anlades. Slutligen fanns en intensiv behandling där ambitionsnivån skulle vara högre än vad som kunde anses vara normalt. Mitt syfte var att studera hur fältskiktets täckningsgrad och artantal påverkats av de tre olika skogsskötselintensiteterna på de tre försöksblocken Bjurholm, Edefors och Harads i Norra Sverige. På dessa block inventerade jag markvegetationen med fokus på fältskiktet i månadsskiftet mellan Juni och Juli 2013.

En jämförelse mellan två datorprogram för utbytesberäkningar :

This thesis is made on behalf of SCA's Forestry Division and is a comparison of two bucking simulation tools: Aptan (manufactured by Skogforsk) and Best/upr (from Berget Systemdesign). The data is based on 32 stands from SCA's forests in Norrbotten and Västerbotten. The objective is to compare the simulations created by the tools with the harvested volumes from those stands. Three variables are needed for the bucking simulation; these are the diameter distribution (at breast height), the relationship function between diameter and height, and the taper coefficients. The volumes of five different assortments from the stands are compared.

Skador orsakade av törskatesvamp på ungskog av tall Pinus sylvestris samt förekomst av kovall i hyggesbrända respektive mekaniskt markberedda bestånd

Törskatesvamp förekommer i två former, en värdväxlande (Cronartium flaccidum) och en icke värdväxlande (Peridermium pini). Genetiska analyser har visat att ingen övergripande genetisk differentiering finns mellan de två formerna och att de därför tillhör samma art. Svamparna tillhör rostsvamparna och angriper i Sverige tall (Pinus sylvestris). Tidigare ansågs de vanligaste alternativa värdarna för C. flaccidum tillhöra släktena Paeonia, Vincetoxicum och Pedicularis vilket ledde till att den värdväxlande formen betraktades vara begränsad till de alternativa värdarnas utbredning, koncentrerad till södra Sverige.

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