Socialist and post-socialist land-use legacies determine farm forest composition and structure: insight from Eastern Germany

European agro-ecosystems host a variety of farm forests that act as primary determinants of biodiversity and ecosystem services. In Eastern Germany, farm forests have regionally increased over the past half century. This paper presents a quantitative and spatially explicit assessment of differences in species richness, diversity, and evenness, as well as forest characteristics and structure, among Eastern German farm forests established during (1) the pre-socialist era (until 1945), (2) the socialist era (1945-1990), and (3) the post-socialist era (after 1990). Aerial imagery was used to allocate forests to each of the three eras, and an inventory of 120 forests was compiled. The results show substantial differences in forest composition and structure. Pre-socialist-era forests are composed of native (mean: 96%), deciduous (mean: 94%) tree species. Mean diameters and species richness values are high. Typical socialist forest species are non-native (mean: 35%) and/or coniferous (mean: 51%). Stands have a uniform, even-aged structure. Species richness/diversity indices are generally low. Post-socialist forests exhibit a high degree of variability. Percentages of non-native (7%) and coniferous (10%) trees are low. The findings suggest that socialist and post-socialist farmland and forest policies translated into distinct land-use legacies in the newly established farm forests, which differ considerably from the composition and structure of pre-socialist forests. We argue that conservation planning should actively consider land-use legacies, which are of particular relevance in the landscapes of Central and Eastern Europe, as these have undergone multiple, abrupt and severe land-use transitions.