The BeechCOSTe52 includes phenotypic trait measurements from individual trees measured in an international network of provenance tests compiled by the COST Action E52 (2006 – 2010). It comprises 39 trial sites and 217 provenances covering the distribution of European beech (Fagus sylvatica L.). The BeechCOSTe52 database provides individual tree phenotypic measurements of height, diameter at breast height, basal diameter, mortality, spring and autumn leaf phenology. The following files are included: Fsylvatica.csv: individual tree measurements by trial and provenance of origin. Trials_coords.csv: geographical coordinates of the trials Prov_coords.cvs: geographical coordinates of the provenances BeechCOSTe52_metadata_descriptor.docx: description of the fields of Fsylvatica.csv, Trials_coords.csv and Prov_coords.cvs databases. Subset_by_trial.R: R script to subset the original database (Fsylvatica.csv) by trial Merge_trial_prov-coords_individualmeasurements.R: R script to merge the coordinates of trials and provenances (Trials_coords.csv and Prov_coords.cvs) with the phenotypic measurements (Fsylvatica.csv). Plot_Trial-Prov_locations.R: R script to map trial and provenance locations. Hplot.R: R script to map tree height variation across provenances and trials. Fagus_sylvatica_EUFORGEN.X: Shape files containing the distribution of Fagus sylvatica from EUFORGEN (http://www.euforgen.org)