Pine-larch forest
A pine-larch forest is a type of forest in the high mountains that forms the upper tree line in the inner-alpine dry valleys. The leading plants of this type of forest are the larch and the Swiss stone pine (Swiss stone pine ).
Both tree species are in a complex competitive environment. The larch is a typical raw soil colonist, the seeds of which are spread anemochorically . The stone pine, on the other hand, is dependent on the hiding place of the common pine jay and, thanks to this spreading strategy , is able to colonize locations that would normally create optimal conditions for the larches. The stone pine is also the typical succession tree of the larch.
The dominance of the larch trees in these high forests can be traced back to human interventions, who used to use the high mountain areas for pasture farming . Without human intervention, the more shade-tolerant stone pine would have gradually displaced the light-hungry larch via the natural forest succession. However, where mountain areas offered themselves for pasture use, humans have deliberately cut out the stone pines and spruces. In this way, light-flooded forests were created, which, similar to the oak forests of the lowlands used for acorn fattening , are suitable for pasture farming. This species shift in the mountain forest in favor of the larch was also supported by the fact that the stone pine is much more severely damaged by browsing and repression . Because of their thick, cork-like bark, larches were more resistant to the forest fires that used to occur very frequently. The alpine pasture economy is only of secondary importance today; This means that the Swiss stone pine would have to regain a larger share of the tree population in the mountain forest through natural forest succession. In fact, in many regions, Swiss stone pines now form a second layer of trees under the light canopy of the larches.
The pests of the Swiss stone pine and larch forest include the gray larch moth , which in the Alpine countries prefers to attack older larch populations in warm and sunny locations. Heavy moth infestation can cause the trees to die. Starting from the larches, the gray larch moth is also able to switch to the Swiss stone pine and also cause lasting damage to them.
Individual evidence
- ↑ a b Swiss stone pine and larch forests of the upper subalpine level. (PDF; 52 kB) In: gebirgswald.ch. Retrieved April 24, 2013 .