This study investigated how structural changes of a historical traditionally used forest landscape in Central
Europe have affected traits of vegetation and wild bee communities. We compared the extent of gaps in the forest
using aerial photographs between 1945 and 2020. And we found historic vegetation and bee surveys from 1975
and 1990, which we repeated in 2010 and 2020. We characterised the vegetation of the closed forest, the forest
gaps and the small-scale meadows adjacent to the forest as well as the wild bee community by traits and
investigated trait changes with Kruskal-Wallis tests. By NMDS we characterised sample plots and transect walks
of timepoints with traits and species. Area of forest gaps decreased by 88% from 1945 to 2020 and by 74% from
1975 to 2020. In the traits of vegetation, Ellenberg Indicator Values (EIV) for moisture and soil nutrients
significantly increased in closed forest, forest gaps and meadows adjacent to forest. The EIVs for light and
temperature, and the number of red list species decreased. The number of wild bee species that specialise in
visiting flowers with long tubes and hylophilic species declined. The number of eremophilic species, species with
longer phenologies, and recently Red list species increased. In the NMDS figure of forest gaps and of adjacent
meadows, different species and traits characterised more recent and older sample plots of vegetation and confirm
the results of the Kruskal Wallis tests. Wild bee communities of 2010 and 2020 were characterised by frequent
species, while those of 1975 and 1990 were not characterised by any species. The traits characterised the wild
bee communities of the older and younger transect walks in accordance with the results of the Kruskal Wallis
tests. In addition, oligolectic bees characterised the older transect walks. The loss of forest gaps represents a
direct loss of habitat for many plant and wild bee species. In addition, the qualitative changes in vegetation
indicate a deterioration in habitat quality for plants of open forests and wild bees. Among wild bees, specialists
were negatively affected by the changes described. These developments were reflected in the initial downward
trend in Red List bee species. The increase in bee species with longer phenology, in eremophilic species, the
decrease in hylophilic species, and the recent increase in red-listed species can indicate climate change.
Therefore, this study underlines the importance of the preservation and development of ecologically valuable
forest gaps, particularly in historical traditionally used forests with a typical species composition.