The Swiss Federal Institute for Forest Snow and Landscape Research WSL

Old timber helps research

This larch disc comes from a beam from a wooden house in the Lötschental valley, in canton Valais. Its 164 annual rings allowed dating the construction of the house to the year 1501.

Wood samples from houses are an important source of data to extend tree-ring chronologies into the past. The resulting reference chronologies are foundational for dendro-archaeologists, who use them to date houses or wooden finds from excavations.

Climate researchers also use timber from high valleys for climate reconstruction. For example, summer temperatures spanning 1,200 years have been successfully reconstructed using samples from wooden houses in the Lötschental.

Tree-ring research at WSL