Fig. 3

Age-density correlation data of oak from 295 study sites. To be considered a successfully regenerated oak stand, the oak regrowth of a certain study site had to meet predefined conditions. Green: positive rating, blue: negative rating. The color of the crosses refers to the rating in Fig. 2. Category 1 (unsuccessful height, see Fig. 2) = 25 study sites, Category 1 (successful height, see Fig. 2) = 8 study sites, Category 2 (successfully regenerated) = 0 study sites, Category 3 (unsuccessful height, see Fig. 2) = 152 study sites, Category 3 (successful height, see Fig. 2) = 64 study sites, Category 4 (successfully regenerated) = 56 study sites