The natural development of the forest in Vorarlberg is evidenced by the distribution of tree types: most areas have a balanced mix of trees with a predominance of spruce. Another sign of the natural cultivation of the forests is the fact that commercial forestry (forests used mainly for timber production) and the protective forest have practically the same distribution of tree types. While in the valleys and southern-facing slopes have mainly beech forests, the proportion of spruce rises with increasing altitude. In Vorarlberg the tree line is at around 1,700 metres, but this can rise to up to 2,000 metres as is the case in Montafon.