Plantetablering efter skogsbranden i Västmanland

Abstract: Fire has been a natural disturbance in boreal forests for a very long time. Species in the forest have evolved and adapted themselves to this disturbance. During the 1900th century big natural forest fires started to decrease because of human suppression and environments created by wildfire in the forest have now become rare. During the summer of 2014 a fire started in the forest of Västmanland, in Sweden. The fire spread and ravaged an area of 14 000 hectares of which an area of 1 500 hectares is owned by the state forest company, Sveaskog. Their intent is to create a park with natural forest dynamics in this area. This report is a study of the plant re-establishment in the park after the fire. The results showed that the plant re-establishment is dominated by deciduous plants. The most frequent species is birch followed by aspen and willow. Earlier studies of forest fire areas shows that the germination is effected by the remaining humus layer. A thin layer, after the fire, gives a better environment for the seedlings to grow. While this study did not show any statistic relationship between these factors, it showed a relation between the soil moisture class and the variety of plants. The amount of pine seedlings was higher on dry soil than on moist soil, while the opposite was true for birch. The study also shows an effect on plant re-establishment due to the intensity of the fire. Aspen, pine and willow were more abundant in areas which were exposed to intensive fire. The conclusion of the study is that there is a rich plant re-establishment in the park and it would be interesting to follow the natural development further on. Wildfires of this size are scarce and we should take care of this opportunity to study the effects and development within the area.