An old forest in Finland is not always an old forest in Sweden
Swedish forests are counted as old several decades later than Finnish ones. That will be the case if the old-forest criteria proposed by the Swedish Forest Agency (Skogsstyrelsen) are approved.
The old-forest criteria stem from the European Biodiversity Strategy, which aims to protect all remaining primary and old-growth forests in the European Union.
Last week the Finnish government adopted its contested old-forest criteria. The main ones are the age of the stand and the amount of deadwood. Both figures vary according to geographical region and the dominant tree species. In coniferous forests, the average age of the dominant stand must be at least 140 years in southern and central Finland and 160-200 years in the north. For broadleaved forests, the age is set at between 100 and 140 years.
In Sweden, by contrast, the main proposed criteria are native tree species and the age of the stand. In addition, the protected area must contain trees at varying stages of decay, must be at least half a hectare in size and must have been undisturbed for at least 30 years.
As regards age, a coniferous or broadleaved forest is regarded as old if the average age of the stand is at least 160 years in southern Sweden and 180 years in northern Sweden. In forests of broadleaved trees other than noble broadleaves, the average age of the stand must be at least 120 years.
For example, coniferous forests in the Tampere region of Finland are classified as old if they are at least 140 years old. In Sweden, coniferous forests at the corresponding latitude are classified as old only if they are at least 180 years old.
Age thresholds for old forests in Finland and Sweden
The lower limit for the average age of a stand is broken down by the following zones – Finland's hemiboreal zone, the southern boreal, the middle boreal, the northern boreal, and the forest and tundra areas of Lapland.
The age range for conifers is 140 to 200 years, and for broadleaves 100-140 years.
In Sweden, meanwhile, the lower limit for the average age of a stand is divided up differently, between southern Sweden (Götaland and Svealand) and northern Sweden (the Norwegian border area and the counties of Dalarna, Värmland and Örebro) – conifers at 160 and 180 years respectively, and broadleaves other than noble broadleaves from 120 years.
Is the European Commission demanding that the criteria be aligned?
What should we make of the differences between Finland and Sweden? Should neighbouring countries apply the same criteria?
“That is a good question. The main criteria come from the European Union and are then interpreted nationally. Even so, both neighbouring countries lie chiefly within the boreal coniferous forest zone,” stresses Ville Šilds, forestry adviser at the Ministry of Agriculture and Forestry.
Earlier this year the World Wide Fund for Nature published a report comparing the efforts of the Finnish and Swedish governments to protect old and semi-natural forests. The organisation's senior forestry expert Maja Suominena (Mai Suominen) says the process of setting old-forest criteria has differed in Finland and Sweden. In Finland the criteria were set in general terms for the biodiversity strategy, while in Sweden they were set more specifically for the Renewable Energy Directive.
“In the end it amounts to the same thing. The purpose of the criteria is to implement European Union law,” notes Mai Suominen. In her view, the European Commission requires that criteria for old forests be aligned between neighbouring countries.
“That process has not begun yet, but it needs to happen. The Commission's mandate is for member states to set national criteria and then to align them. For Finland that would apply both to Sweden and to the Baltic states, but from a practical point of view the alignment of the Finnish and Swedish criteria matters most.”
As usual, the World Wide Fund for Nature is satisfied with neither country's criteria for old forest areas. “Neither country's criteria are scientifically grounded. Scientists should have drawn up the criteria, on the basis of which the government would first have carried out an impact assessment and only then taken a decision,” argues M. Suominen.