Höjdtillväxt, överlevnad och skador i praktiska etableringar av hybridaspbestånd i södra Norrland, anlagda 2004-2011

Sammanfattning: Hybrid aspen is a crossbreed between European and North American aspen. It is a fast growing tree species that has shown strong growth in the South of Sweden. The follow-ups that have been made on hybrid aspen stands, have mainly been done on plant material in the South of Sweden. In the North of Sweden, only occasional studies have been made, and the knowledge of Northern hybrid aspen stands is, thus, unsatisfactory. In the South of Norrland, land owners have planted hybrid aspen, but what kind of plants it is, and how well these stands have established, is not ascertained, since data has not been compiled on the subject. The objective of this study is to evaluate practical plantations of hybrid aspen in the South of Norrland regarding height growth, survival and damages. The ambition is to increase the knowledge about practical plantations regarding height growth, survival and damages, and from the conclusions thereof, give recommendations for future establishments of hybrid aspen in the area. For the study, eight hybrid aspen stands in the South of Norrland were localised. Inventories were made of the stands, the land owners were interviewed and the material was compiled and analysed. Annual height growth varied amongst the stands between 0,4 and 1 meter and was in average 0,6 meter. Survival varied between 41 and 100 percent, with a mean value of 70 percent. The proportion of damaged stems varied between 0 and 85 percent, with a mean value of the stands of 27 percent. Plant mortality was explained by the land owners to be a result of field-mouse damages, which is confirmed by earlier research. The examined hybrid aspen stands in the South of Norrland demonstrate varying results in terms of height growth, survival and damages, but mainly a result that makes the tree species interesting as an alternative to traditional tree species.