Interesting facts 

Diverse Forests

Forests are shaped by climatic conditions, so the types of forest found on the north and the south side of the UNESCO World Heritage site are very different from each other. At mid-range altitude on both sides are extensive forests of spruce with a full canopy. But above and below the spruce level clear differences can be seen.


In the Bernese Oberland, the lower slopes are populated by deciduous forests of beech, sycamore, grey alder and ash among others. As the altitude increases, the deciduous trees give way to spruce. 
On the Valais side there are practically no deciduous forests. The so-called montane zone is overgrown with Scots pine. This tree, which is basically a northern species, is at the very edge of its distribution in the Valais; it is therefore sensitive to heat and drought, and in the last few decades has been dying off over wide areas. Where the Scots pine is disappearing, it is being replaced by the downy oak, which is better suited to the almost Mediterranean habitat. Very typical of the Valais are the sparse forests of larch and Swiss stone pine, growing above the spruce forests of the subalpine zone.

The Aletsch forest at the edge of the Great Aletsch glacier has enjoyed total protection since 1933. Its use by humans came to a complete stop; even dead wood stays where it is. The rotting wood of dead trees provides a habitat for numerous plants and animals. Fungi, lichens, mosses, dwarf shrubs and even young trees thrive on the dead wood; an amazing diversity of flora and fauna emerges as a result of this “untidiness”. The Swiss stone pine is the dominant tree species in the Aletsch forest. It grows very slowly but reaches a great age – some are up to 1000 years old. This makes them to the oldest trees in Switzerland. The resin of the Swiss stone pine contains a high proportion of essential oils. They protect the tree and increase its resistance.