Figure 1

Trajectories (mean values ± std error) of (a) total stem density (n/ha), (b) stem density (n/ha) without height class one (< 10 cm) and (c) maximum heights per tree species for an 18-year time span, separated for the fenced plots (F) and the unfenced control plots (U); trajectories are separated for (A) the main tree species, also indicated with an + , and (B) co-occurring species. Species are ordered by their overall mean value (for total stem density, stem density without height class one and for maximums heights, respectively). Fraction numbers above the trajectories depict the number of main or co-occurring tree species on the fenced or unfenced plots, which show higher mean values (in terms of stem numbers, heights) than the remaining fraction. 3/5 at the first year of records of mean heights in panel A on the unfenced plots means, that three out of five main tree species are on average higher than the remaining two tree species. Aal Abies alba, Apl Acer platanoides, Aps Acer pseudoplatanus, Bpe Betula pendula, Fex Fraxinus excelsior, Fsy Fagus sylvatica, Lde Larix decidua, Msy Malus sylvaticus, Pab Picea abies, Pav Prunus avium, Psy Pinus sylvestris, Qsp Quercus sp., Sar Sorbus aria, Sau Sorbus aucuparia, Sca Salix caprea, Tba Taxus baccata, Ugl Ulmus glabra. Please note the different, scaled y-axes in the diagrams.