European larch sapwood: A model for predicting the cambial age and for a more accurate dating

European larch (Larix decidua Mill.) holds significant importance as a forest tree species throughout the Alps and in certain regions of central Europe. Its extensive use as construction timber has made it a subject of substantial interest in dendroarchaeological studies aimed at understanding the long-term interactions between human societies and forests. Precise dating of felling phases, accurate estimation of the age of harvested wood, and information on the geographical origin of wood play a crucial role when it comes to characterize these interactions. In this study, we compiled a large dataset of L. decidua samples from across the European Alps to provide a robust statistical model that predicts the cambial age of L. decidua trees based on the number of heartwood rings. By extension, this model can be used to estimate the number of sapwood rings so as to approximate the felling date and to more precise date archaeological larch timber. The model requires almost complete heartwood sequences (<5 missing rings) to achieve accurate estimations. Our results also evidence that the ratio between the number of sapwood and heartwood rings varies across the Alps. At the same time, the indicator developed in this work is not suitable for a determination of wood origin, raising doubts about the effectiveness of attempts aimed at dendroprovenancing L. decidua based on sapwood.