Fig. 1

Location of the study area (region of provenance 1) within the maritime pine distribution area in Northern Iberian Peninsula and Southern France. Plots used in the Third Spanish National Forest Inventory (SNFI3) where the presence of maritime pine was detected (green dots) and site index (SI) research plots used in the present study (red dots). Below (left) scatter plot of showing the plots used in this study superimposed on the bivariate plot of annual mean temperature and total annual precipitation