Forest Report 2015: Condition and Use of Swiss Forests

The forest in Switzerland covers a third of the country’s surface. The forest area in the Alpine regions has increased continuously for 150 years, and by as much as 7 per cent since the 2005 Forest Report alone. In many places stands have become denser. The overall growing stock has increased by a further 3 per cent, although not as much as in the previous period. The growing stock on the Swiss Plateau has, however, decreased, especially that of spruce, which has diminished by almost a third. Since the overall growing stock is greater, the forest serves as a sink for increasing amounts of CO₂.

Since 2005, Swiss forests have been spared disastrous storms. Sulphur deposition from the atmosphere has decreased further. In contrast, high nitrogen deposition and increasing soil acidification still disturb the nutrient balance of trees. Defoliation and tree mortality have remained, on average, stable for many years, but periodically they have increased strongly due to droughts and insect infestations. The rate of unwanted introduction of alien animal, plant and fungal species has continued to increase markedly since 2005. The ongoing climate change will, in future, be even more of a challenge for the forest and forestry.

Since the Forest Report 2005, both the wood increment and the growing stock have continually increased, while the amount of harvested wood sold has decreased. During the same period, the harvest of logs and industrial timber has decreased and that of energy wood has increased. In addition to wood, non-wood products such as forest honey, venison or mushrooms can also be obtained in the forest. Of the non-wood products, the sudden drop in sweet chestnuts stands out: the harvest has really caved in as a result of damage caused by the sweet chestnut gall wasp. In Switzerland, the use of the forest is covered in the Forest Act. Forest planning implements this legislation and also ensures the sustainability of all forest functions.

Forests play a central role in maintaining biodiversity in Switzerland. Since the Forest Report 2005, about half of the forest reserves planned for completion by 2030 have already been established, and the populations of forest birds, large carnivores and wild ungulates have grown. Despite these positive developments, some problem points still remain. Thus open forests and late phases of forest development with old trees and deadwood are rare in the lowlands, and the total number of vulnerable species has not decreased.

Forests protect groundwater, an important drinking-water resource, from impurities by retaining pol-lutants in the soil and allowing the cleaned water to percolate deep into the ground. Drinking water from forest areas is therefore of good quality. Forests provide people with protection against natural hazards, like avalanches, rockfall and debris flows. Their protective effect has improved since 2005 because the forests have grown denser. The increasing lack of regeneration and more browsing of young trees by wild ungulates mean, however, that the forest’s long-term protective effect is uncertain.

The criterion social economy describes how forestry and the wood industries relate to society. The emphasis here is on the economic and social aspects of sustainable forest management. Since the last Forest Report in 2005, the importance of these aspects and the complex relationships between them have noticeably increased – for example, the way the general public influences forest management. Conflicts over how to use the forest are increasingly the cause and the result. The forest service of wood production and other services such as protection and recreation are increasingly being viewed as related to each other, with wood production re-gaining importance. This development is caused, among other things, by both the energy transition and the generally difficult economic situation of the owners and partners in Swiss forestry.