Tree ring dendroarchaeological data from the French Pyrenees (BENDYS project ANR-19-CE03-0010)

We carried out an archaeological census in the northern slopes of the Pyrenees which led to the acquisition of 393 tree-ring series from fir (Abies alba Mill.), deciduous oak (deciduous Quercus), beech (Fagus sylvatica L.), pine (Pinus sp.) and poplar (Populus). We successfully cross-dated 124 series from fir trees, while the other 269 series remained undated. The tree-ring series were extracted from building timbers used in barns located in the immediate vicinity of current old-growth beech-fir forests. The wooden pieces also comes from houses and churches close to the forests, where the timbers are also preserved in the frameworks, ceilings and joineries. The samples were taken by coring and sectioning. The resulting chronology covers the period 1446-1952 AD, but includes a hiatus over the period from 1655 to 1679. The ring series measurements were performed with a LINTAB measurement table combined with TSAP-Win program for recording measured values. The series were cross-dated with the DendronIV program. Our study provides the first dated tree ring series for fir in the French Pyrenees. This research was funded by the ANR-BENDYS project ANR-19-CE03-0010 led by Vanessa Py-Saragaglia and the GEODE CNRS UMR 5602 laboratory. We would like to thank Sylvie Ladet (INRAE Dynafor UMR 1201, Auzeville-Tolosane, France) and Emilie Lerigoleur for their contribution. The data provide a valuable reference chronology, useful to dendrochronologists and archaeologists for dating other tree-ring chronologies from living wood, timbers, buildings or archaeological sites. Paleoenvironmentalists, dendrochronologists, forest ecologists will be able to benefit from this data to reconstruct fir tree sensitivity to climate, and forest resilience and disturbances over the last 500 years. Rural building tree ring series can be used to study wood uses and economy in the mountains in modern times (16th -19th c.). The .fh files can be opened in most of all dendrochronology programs and can be used in R in the dplR package.