A forest fire is a naturally or human triggered fire in the undergrowth or on forest- and grass soils.
› How are forest fires caused?
Incidence of forest fires in Switzerland
Forest fires in Switzerland arise mainly in the cantons of Valais, Graubünden and Ticino and mostly affect small areas. Forest fires in our climate region are mainly caused by humans. Due to climate change, the frequency and extent of heat waves and periods of drought are set to increase further in the future and this also increases the risk of forest fires in Switzerland. Thus it is expected that the increased probability of forest fires will result only in more forest fires on the southern slopes of the Alps in Valais but also for the first time on the northern slopes of the Alps
In one of the biggest documented forest fires in Switzerland, around 200,000 trees over a forest area of 300 ha burned to the ground above Leuk (Valais) in August 2003. The forest area destroyed by the fire extended from an altitude of 800m to the tree line at 2100m. Approximately 20% of the destroyed forest area was protective forest that protected the commune of Leuk and the road to Leukerbad. Thanks to the large-scale deployment of the fire brigade and favourable wind conditions, it was possible to prevent an even bigger disaster and there were no injuries or casualties. The damage caused by the fire is still visible today. Because the regrowth of trees is very slow under difficult climatic conditions (inner Alpine drought), it will be a very long time before the forest can fulfil its protective function in full again.