For many centuries, forests in Switzerland have been driven back ever further. In addition to increasing the arable and pasture land, the forest was also cleared to obtain wood for fuel, construction and later for industry. This trend was reversed in the mid-1800s, when thanks to the construction of the railways, large amounts of cheaper coal could be imported, increasingly replacing the use of wood for fuel. Furthermore, in 1876, due to the effect of repeated natural disasters, the Confederation issued a prohibition of forest clearing and ordered the large-scale reforestation of protective forests in mountain regions. To the present day, the Forest Act requires compensation for forest clearing, provided that the clearing is not of areas that have grown recently, and in addition to forestry use and protection from natural hazards, also mentions recreation (“well-being”) as one of the forest’s important functions.
Forest regrowth in Switzerland continued slowly but surely throughout the period observed in the land use statistics between 1985 and 2018. Altogether, in the space of just over three decades, wooded areas increased by 589 km2 or 5%. This growth was u-shaped: while wooded areas grew on average by 23 km2 yearly between 1985 and 1997, this figure dropped in the following observation period (1997–2009) to 10 km2 , only to rise again in the most recent period (2009–2018) to 22 km2 per year. The considerably slower expansion of wooded areas between 1997 and 2009 could be explained, amongst other things, by the agricultural direct payments introduced in 1999. These created an incentive for farmers to start using alpine agricultural areas again that had previously been practically unviable, instead of letting them gradually become overgrown with trees. The increase in the wooded area in the long term is mainly due to the alpine agricultural area becoming overgrown.
The expansion of wooded areas between 1985 and 2018 took place first and foremost in the pre-Alps and Alps. The regrowth of forests was particularly marked on the southern flanks of the Alps, in the Gotthard region and in parts of lower Valais. Overall one can say that: The higher the location, the greater the percentage increase in the wooded area. In zones higher than 2000 meters above sea level, i.e. in the region of the treeline, the wooded area has grown by over a third. Below 1000 meters, however, the size of the wooded area has remained fairly stable.