The County Administrative Board of Dalarna conducts controlled conservation burnings in nature reserves to increase biodiversity. The fire increases diversity in several ways by attracting fire dependent organisms, increasing the number deciduous trees, enhancing the volume of dead wood and bringing morphological diversity as fire scars on trees. After the burnings deciduous trees usually increase, but to reduce grazing from browsers (who would consume most of the deciduous biomass) fences can be used to exclude the grazers.   In the first part of my study I inventoried tree status after two controlled nature conservation burnings in eastern and northern Dalarna (Trollmosseskogen and Rensjön). The aim was to increase the knowledge of fire effects on trees and to find out if the desired results were achieved on diversity. The results show that the number of tree species has increased in Trollmosseskogen. Fire damages on trees were more common in Rensjön than in Trollmosseskogen. In both nature reserves the volume of dead wood has increased successively over time which suggests that the fire gives prolonged effects on tree mortality. This shows that long-term inventories are important to do to get an overall picture on the effect on tree mortality.   The second part of my study deals with Vändleberget, a nature reserve that was fenced 2005 after burning to protect particularly deciduous tree re-growth from browsers. Tree inventories and measurements were performed by placing plots both inside and outside the fenced area. Tree height and tree diversity showed a trend towards higher levels inside the fenced area, but the differences were not significant. Stem density, in total, is very high in the investigated area in Vändleberget and therefore I suggest selective logging to promote deciduous trees such as aspen (Populus tremula), ash (Fraxinus excelsior), oak (Quercus robur) and goat willow (Salix caprea). Spruce (Picea abies) and some trivial deciduous trees, especially birch (Betula spp.) can be removed. When the remaining trees are about four meters high I suggest that the fence can be taken down, as at that height the browsers can no longer harm the deciduous trees severely by eating the top of the trees or physically breaking the tree trunk.    To conclude, I found that conservation burning increases biodiversity on several levels such as number of species and morphological diversity. Fences can be used to reduce grazing which could promote tree diversity.

A threat is that some of the tree species that are important for the biodiversity are under a lot of pressure because of the high browsing activity. The Swedish forestry agency has now together with the forest industry set an acceptable level of browsing on production forest that 70% must be non-browsed when the stands are 5 meters or higher. To protect the production forest from browsing the landowner can choose from several options, the conventional way is yet to point treat every production plant with a game repellent, but that way isn’t very time saving as to treat with this new method.This study is trying out a new method to treat the whole stand instead of point treating every production plant. The method was to use a petrol mistblower (Stihl SR200) and treat one hectare with 9 litres of water and 1 litre of the game repellent Trico viltskydd. Two inventories were made, one before treatment and one after treatment. In total 200 sample surfaces of 2,82m in radius where collected, 100 of them where control surfaces. Every tree species in the sample surfaces where record and if it was or wasn’t browsed. The result of this study shown that the increase of browsing on all tree species was reduced with the treatment method. The new method shows that it can have positive effects on preserving the bio diversity.