Evaluating a Forest Conservation Plan with Historical Vegetation Data – A Transdisciplinary Case Study from the Swiss Lowlands

Forest types shaped by humans host a specific set of plant species that may disappear subsequent to the abandonment of traditional uses of the forest. To improve the effectiveness of conservation management for plant species associated with traditionally managed forests, information on historical forest conditions and plant occurrence is vital. In the Swiss Canton Zurich, an action plan to promote light forests has been initiated by the state office for nature protection. This action plan has defined a set of 172 target species for light forests. In order to evaluate in which forest types these species occurred historically, we combined a vegetation survey from 1907 from the wooded mountain range of Lägern (Switzerland) with information on forest structure in the early 20th century based on forest management plans. For 21 target species, 181 locations were determined and linked to historical forest structures. We recommend enhancing the effectiveness of the action plan for light forests by recreating coppice-with-standard forest on productive soils, considering the role of non-timber forest uses for ecosystem development, and engaging private forest owners to assist in the creation of light forest reserves.