The restoration period : a new era in forestry

Sammanfattning: In the last 200 years the boreal forests of Sweden have undergone a dramatic transformation. After a long history of high grading the largest trees foresters grew increasingly concerned about the state of logged over forests. The big question was how to regenerate and increase the productivity of sparse forests. Single storied forest management had been successively introduced in the beginning of the 20th century and in the 1940ties foresters came to the conclusion that this was the best way to create what they considered as healthy productive forest stands. This led to the creation of a “forest restoration program” initiated on the state-owned forests in 1950. A 20 year program that aimed at replacing forests with poor growth and low standing volumes with young growing stands that ensured long term yield. In this study I have investigated why the restoration program was initiated and what ecological and forestry related effects it has resulted in. The study is based on both historical management plans for a state owned forest management unit that was restored, articles in the Journal of the Forestry Association of Northern Sweden and a field inventory of an area that was not restored. Three driving forces that initiated the restoration program was found in my analysis. Firstly, foresters came to the conclusion that forests did not regenerate themselves as fast as they were harvested. Secondly, foresters agreed that the insufficient regeneration was due to the forestry method used, i. e. selective logging. Thirdly, forestry laws and policies progressed over time and came to include demands on forest regeneration, this resulted in so called “restart’s” in areas where no new stands had established after harvest. My results from the time series analysis showed that the growing stock of the studied management unit has increased from 32 to 76 m³sk/ha from 1907 to 2022. At the same time, there is a severe lack of old forests and multistoried forests have been entirely eradicated from the management unit. The forests in Hästkullens nature reserve, an area within the management unit that was not restored, looks very different. Old trees, dead wood and trees of different sizes and ages are present in the area. This makes the area important from a biodiversity perspective. The restored forests surrounding Hästkullen share its early history but do not hold the same nature values. My conlusion is that the forests in northern Sweden would have looked very different and todays negative trend for nature conservation ad biodiversity could have looked very different if the restoration program had never occurred.