Fig. 7

Provenance clusters. The provenances planted in the Austrian trials were clustered into three provenance or seed origin attributes based on A variety of Douglas-fir, B altitude of provenance origin, C climate of provenance origin. The climatic cluster was based on PCA of all the 20 bioclimatic variables (see Table 1) of provenance origin and thereafter K-means clustering of the first three principal components into four groups