Hurricane Lothar of 1999 also has positive consequences
The Swiss Federal Institute for Forest, Snow and Landscape Research has studied the consequences of hurricane Lothar, which swept across Switzerland 20 years ago. This caused major damage in the forest, but also created mixed deciduous forests rich in species.
Lothar swept across Switzerland on December 26, 1999. The hurricane brought 12.7 cubic meters of wood to the ground, according to a Media release of the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) is called.
Subsequently, there has been a bark beetle infestation, so that the damage has reached a total of circa 1 billion Swiss francs. 20 years later, however, the WSL researchers also see positive consequences.
Risk of bark beetle infestation contained?
The bark beetle infestation as a result of Lothar can be explained on the one hand by the heat in 2003 and on the other hand by the fact that a large occurrence of bark beetles is almost always recorded after storms that bring large quantities of trees to the ground. Therefore, bark beetles could again pose a threat to Swiss spruce forests precisely because of climate change.
"Three instead of two generations of beetles are then likely to develop in the Swiss Plateau, attacking weakened spruce trees," insect specialist Beat Wermelinger of WSL is quoted as saying in the release.
More robust forests could grow back
Against this background, it is gratifying that in the places where Lothar threw large quantities of trees to the ground, young forests 10 to 15 meters high are standing again today. However, these forests are much more species-rich than was the case before Lothar. "There are many indications that climatologically robust forests are growing back here, with additional species such as oak, cherry tree and Norway maple," says WSL forest scientist Peter Brang.
In the long term, then, the catastrophic destruction of Lothar has had a stabilizing effect on the forest, WSL says. "The knowledge gained from forest practice and research after the storms helps to better understand natural forest dynamics and to recognize disturbances as an opportunity for rapid adaptation," says WSL forest ecologist Thomas Wohlgemuth.
