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227 Uppsatser om Scots pine. - Sida 1 av 16

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was studied on 12 sites in coastal areas of northern Sweden. On each site, sample plots were placed in adjacent Norway spruce and Scots pine stands with similar ages in between. Basal area, tree height, Site Index, volume production, simulated maximum mean annual increment (MAImax) and tree vitality were compared for the two species. Average basal area at the time of measurement was 30.4% larger for Scots pine stands than for Norway spruce stands. The difference between the two species in basal area increment during the last 10 years was related to stand age.

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.

Contortatallens odlingsvärde i Götaland

The third most common conifer in Sweden is Pinus contorta (lodgepole pine). It originates from the western part of North America and was brought here in the end of the 1920s. The lodgepole pine is today allowed for commercial plantations in central and northern Sweden, excluding high altitude locations. Since 1979 only plantations with scientific purpose are allowed in south-central and south Sweden. This document is focused on how lodgepole pine manage perform compared with Pinus sylvestris (Scots pine) in the southernmost part of Sweden, Götaland. The idea came from the fact that the Swedish government is evaluating a notification from the National Forest Agency that suggests lodgepole pine to be allowed for commercial plantation even in southern Sweden.

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.

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.

Är förekomst av knäckesjuka i tallföryngringar mindre på stora naturvårdsaspar än på aspsly?

Pine twisting rust (Melampsora pinitorqua) is a parasitic rust fungus found all across Sweden causing damage resulting in lower quality and reduced tree growth in pine stands. In Sweden, the fungus is dependent on two alternate hosts; European aspen (Populus tremula) and Scots pine (Pinus sylvestris). Pine twisting rust has five different spore stages, two of them (uredinio- and teliospores) on the leaves of aspen. Injures on aspen caused by pine twisting rust is not extensive. On the other hand, when it infects the annual shoots of Scots pine it often results in a bent steam or even a top shoot breakage.

Trädslagsinverkan på markvegetationens utveckling i odlingsförsök med tall och contorta :

In the 1970?s it was predicted that in the beginning of the 21st century there would be a timber shortage in Sweden and a large scale introduction of the exotic tree species lodgepole pine started. An introduction of a foreign tree species means a risk of a negative influence on the forests ecosystem. Today, the stands that were established in the 70?s are middle-aged and the effect on the forest floor vegetation can be studied.

Modeller för brösthöjdsålder för tall och gran :

The purpose of this study was to develop two types of prediction models for Scots Pine and Norway Spruce. The first type for calculation of the stump diameter under bark the year the tree reached breast height (Dstubh130). The second type for calculation of the annual difference, e.g. the number of growth years between stump height (0.2 m) and breast height (1.3 meters above ground level). The primary thought with these prediction models is to obtain the breast height age in the trees on basis of the number of annual rings at stump.

Granföryngring på tallmark, hur ofta förekommer det? :

This survey was made during the summer of 2004 and the spring of 2005, on commission from the National Board of Forestry. The aim of this report was to investigate how often Norway spruce (Picea abies L. Karst), is planted on poor Scotch pine (Pinus Silvestries) sites and if it affects the yield of Norway spruce? In order to investigate this, data from 29 stands witch had a lower site index than T24 was collected. The investigated stands were situated in the southern-eastern Sweden. In 20 plots in each stand, the highest tree, age, number of seedlings, site index and tree species per stand were measured.

Undersökning av självspridning av contortatallen i norra Sverige

Over the past 40 years 600 000 ha of lodgepole pine (Pinus contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions. A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.

Jämförelse mellan sådd och naturlig föryngring av tall i Härjedalen

The purpose of this study was to compare naturally regenerated Scots pine (Pinus sylvestris (L.)) against seeded Scots pine in terms of benefits and differences. An inventory was performed at a number of different sites, 4 ? 6 years after soil scarification and data on the number of new established plants, their height growth as well as ground-line diameter was collected. Information about site conditions such as altitude, quarter exposure and frost risk was also collected. A review of previous studies was conducted in addition to the field study.

Postningsoptimering vid sönderdelning av fura vid Säters Ångsåg :

The aim of this project is to optimise the sawing patterns used for sawing Scots pine at Säters Ångsåg AB. The thesis has a theoretical approach and does not claim to be fully applicable in a practical point of view. The input used in this project is last year?s sales volumes and prices of sawn products. The input of the timber is collected from the database ?VIOL?.

Anlockning och gnag av snytbaggar (Hylobius sp.) : effekt av plantstorlek och behandling med metyljasmonat

Two field experiments were conducted in central Sweden in order to: 1) Determine a relationship between the number of approaching pine weevils (Hylobius sp.) and the number of attacks by pine weevils, in relation to the size of seedlings of Scots pine (Pinus sylvestris). 2) Determine if application of methyljasmonate (MJ) on seedlings of Scots pine will result in higher resistance towards attacks by pine weevils and/or have any effect on the number of approaching pine weevils. The field experiments were designed with two separate parts in close vicinity on the same clear cuttings: a) pitfall traps placed in patches of scarified soil that caught approaching pine weevils at 2.5 cm from the bait, which consisted of different sized seedlings of Scots pine some of which were subjected to application of MJ and b) the same type of seedlings planted out in patches of scarified soil. The first field experiment was conducted on a 1-year old clear cutting outside Uppsala in east central Sweden and the trapping part of the experiment consisted of 8 blocks with 6 treatments: 1) control, 2) small over-wintered seedling, 3) medium sized seedling, 4) medium sized seedling treated with 0.5 ml 100 mmol MJ 4 days prior to start of experiment, 5) large seedling, 6) vial with 9.5 ml of ?-pinene. The trapping experiment lasted for 6 weeks in the early summer.

Spatt relaterad till tarsalledens vinkel

The effectiveness of Phlebiopsis gigantea to prevent spore infections from Heterobasidionannosum and Heterobasidion parviporum on hybrid larch stumps were investigated in fivestands in southern Sweden. All sites are former forest land and the age of the trees wasbetween 9 and 13 years.The study was implemented in August 2010, a month where spore dispersal should be great.The five sites were located in previously un?thinned monocultures of hybrid larch. The sporeload in the air was studied with the help of spore traps from three different tree species;Norway spruce, Scots pine and hybrid larch. A total of 146 spore traps, evenly distributed inall five sites were analyzed.

Effekten av metyljasmonat som skydd mot gnag av snytbagge (Hylobius abietis) på gran- och tallplantor :

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.

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