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115 Uppsatser om Pinus contorta - Sida 1 av 8

Föryngringsresultatet efter sådd av contortatall (Pinus contorta Dougl. var. latifolia Engelm.) i Härjedalen

Den här studien är en uppföljning av föryngringsresultatet efter maskinell sådd av contorta (Pinus contorta Dougl. var. latifolia Engelm.) i Härjedalen. Efter tre växtsäsonger uppgick det totala antalet såddplantor till 3 700 per ha och antalet huvudplantor uppgick till 1 800 per ha. Andelen nollytor uppgick till 2 %.

Diameter- höjdskillnader för klippgran (Abies laciocarpa), gran ( Picea abies), glasbjörk (Betula pubescens) och contorta (Pinus contorta) i Strömsunds kommun.

Det finns ett stort intresse för exoter inom skogsbruket och i denna rapport behandlas klippgran (Abies laciocarpa) och Contorta (Pinus contorta). Vid undersökningen av dessa trädsorter jämfördes diameter och höjdtillväxt med gran (Picea abies) och björk (Betula pubescens). Mätningarna utfördes på lokaler i Strömsunds kommun i Jämtlands län vid Näxåsen (Strömsund) och runt Jorm i Frostviken på SCA:s marker.

Självspridning av contortatall (Pinus contorta) på impedimentmark i Sverige

I Sverige finns det ungefär 475 000 hektar skogsmark där den från Kanada introducerade contortatallen (Pinus contorta) utgör mer än 65 % av den totala grundytan. Genom aktiv skogsanläggning har P. contorta blivit Sveriges sjunde vanligaste trädart sett i ett volymmässigt perspektiv. Därför är det av stor vikt att ha god kännedom om hur arten sprider sig i det svenska skogsekosystemet. När P. contorta introducerades ansågs den sakna förmåga att självsprida sig (fröså sig), men senare visade det sig att andelen serotina kottar varierar mellan olika träd och att den kan självsprida sig på produktiv skogsmark. Resultatet av studien visar att P.

Tillväxt och potentiell sågtimmerkvalitet i gallringsmogna jämförelseplanteringar med Pinus contorta och P. sylvestris :

The Swedish Cellulosa Companiy, SCA, has today 280 000 ha planted with lodgepole pine (Pinus contorta var. latifolia) (?C?) which is equivalent to 14 % of its total forest area. Exotic lodgepole pine has in previous experimental stands shown a superior growth than the native Scots pine (Pinus sylvestris L.) (?S?).But also the comparison could be questioned because stand histories were was unknown and also differences in age between C and S existed.

Potentiella arealer för ökad virkesproduktion i norra Sverige genom skogsodling med Pinus contorta var. latifolia, Larix sukaczewii, Abies lasiocarpa, Populus × wettsteinii och Picea mariana

Sweden is a country with few native tree species. According to Govt. 2007/08: 108, exotic tree species may be seen as an opportunity to increase the growth of tree volume in Sweden. Potential areas where explored In this work for cultivation with Pinus contorta var. latifolia Engelm., Larix sukaczewii Dylis, Abies lasiocarpa (Hook.) Nutt., Populus × wettsteinii Hämet-Ahti (tremula x tremuloides) and Picea mariana (Mill.) Britton et.al.

Comparison of bird communities in stands of introduced lodgepole pine and native Scots pine in Sweden

The introduced lodgepole pine (Pinus contorta) occupies more than 650 000 hectares in Sweden. There are some differences between lodgepole pine and Scots pine (Pinus sylvestris) forests which could affect bird assemblages, for example differences in canopy density and ground vegetation. Birds were surveyed in 14 localities in northern Sweden, each characterized by one middle-aged stand of lodgepole pine next to a stand of Scots pine. The two paired stands in each locality were planted by the forestry company SCA at the same time and in similar environment to evaluate the potential of lodgepole pine in Sweden. In those 14 localities, one to three point count stations were established in both the lodgepole pine and the Scots pine stand, depending on the size of the area.

Pinus contorta susceptibility to Heterobasidion spp. : a study of stumps, roots and artificial spore infections of stumps

The Lodgepole pines susceptibility to Heterobasidion spp. was investigated in three parts ofthis study. In the first part, discs from freshly cut stumps were collected and analyzed to seeif the fungi can spread and grow naturally in Lodgepole pine stands. In the second part, rootsamples were collected from Lodgepole pines planted in former infected Norway sprucestands to see if the fungi can spread through root contacts. For the third part, new stumpswas created and artificially infected with spores of both the S?type (H.

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.

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.

Jordlöparfaunan i bestånd av contortatall (Pinus contorta) och svensk tall (P. sylvestris) 1987 och 2010

In the 1970´s the North American lodgepole pine (Pinus contorta) was introduced to Sweden in large scale. The lodgepole pine affects its new environment different from Scots pine (P. sylvestris), leading to a change in biological diversity. Forestry today affects the ground beetle fauna (Carabidae). Habitat specialists associated with older forests are first affected. When the canopy closes again after a clear-cutting species that prefer open habitats reduces and those who prefer mature/closed forests increase. In this study we compare differences in diversity and community structure of ground beetles in stands of lodgepole pine and Scots pine.

Planteringsförbandets betydelse för kvalitetsegenskaper i Contortatall (Pinus contorta var. latifolia)

In Sweden, large scale planting of Lodgepole pine (Pinus contorta var. latifolia) started in the beginning of the 1970?s. At first, the aim was production of pulpwood, but later, also production of timber became considered realistic. Today, Sweden has more than 520 000 ha of Lodgepole pine.

Inverkan av årstid för förstagallring på avverkningsskador i contorta och tall :

SCA har idag cirka 280 000 hektar beskogad med contortatall (Pinus contorta Dougl. ex Loud. var. latifolia Engelm). Stora delar av den arealen har kommit in i, eller är på väg in i, gallringsbar ålder.

Picea mariana ((P. Mill.) B.P.S), P. abies (L.), Pinus contorta (Dougl.) och P. sylvestris (L.) : en jämförelse av produktion och potentiell kvalitet hos försöksbestånd i Jämtlands län

Swedish forests are dominated by just two conifer species Norway spruce and Scotch pine. They are not able to achieve the highest possible production or fulfill industry demands for raw materials. The introduction of exotic conifers can potentially meet these shortcomings and present a relevant solution. This study was conducted in a block experiment with ten blocks planted in 1987 by SCA in North Sweden. The objective of the block experiment was to study if Black spruce is an appropriate alternative to Lodgepole pine, Norway spruce and Scotch pine on different site classes.

Renens fejskador på tall- och contortaplanteringar inom Malå samebys höst- och vinterbetesområden :

The effects of Reindeer mechanical damages on the planted regeneration of Pinus sylvestris and Pinus contorta. Semi-domesticated reindeer can damage young trees. In late winter reindeer rub their antlers against young trees. The aim of this study was to quantify those damages. This study covered planted objects from three different areas in northeastern Sweden.

Utbyte av massaved och biobränsle i några typbestånd av Contorta :

The aim of this study is to describe a number of type stands of lodge pole pine in Norrbotten with respect on stem volume and total biomass. Further questions to answer is if there is stand characteristics that make the stands more suitable for pulpwood in early thinning, or if it is better to apply whole tree harvest. The study shall also give an indication if bio energy can be an economical interesting alternative for Sveaskog. Sampled trees represented the variation in the different stands. Five trees were selected from each stand to represent that stand. Stem volume and biomass (kg dry weight (DW) per hectare) for each fraction was calculated.

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