Svartgran – ett alternativ när allt ser mörkt ut? : en kartmodell för att visa lämpliga ståndorter för odling av svartgran

Abstract: A common problem in forestry is plant death caused by frost. The risk of frost is highest on wind protected, flat or low-lying areas in the terrain. Here you often have regeneration problems with Norwegian spruce which is especially sensitive to spring frost. Swedish tree experiments have shown that the black spruce can be a suitable alternative on these areas, for example on moisture frost prone areas. The species originates from North America and its pioneer tree characteristics make it more frost hardy than Norwegian spruce. It is also relatively free from damages and in Canada the light wood makes it sought after as pulpwood. In this study areas suitable for culturing black spruce in northern Sweden were identified, where it can compete with Norwegian spruce. By the creation of a map model based on different map material, the suitable areas could be selected. First, a slope model including low-lying and flat areas of a certain size was created. Thereafter a selection of the different land covers was made in a map layer. The land covers that were selected were forested mires, peatery and swamp forests. When the slope model and the selected land covers were run together it resulted in a polygon map with areas that met the requirements of land cover as well as slope and surface area. To be able to present the result in a suitable way, the area within Åsele municipality was chosen as delimitation. The total area of suitable black spruce areas within Åsele municipality was calculated to 7118 ha. That corresponded to about 1,6 % of the total land area, when water surfaces was excluded.