Forest ecosystems in Germany are under massive pressure: In recent years, forests have been severely damaged by droughts, air pollutants, pests and fires. In the future, the ongoing climate change as one of the main drivers of this situation might lead to a further deterioration of the forest condition and to a destabilisation of forest ecosystems in the long term, if it should prove impossible to make them more resilient to climate change.

The conversion of monocultures or species-poor forests to site-adapted, species-rich, mixed-age stands and near-natural mixed forests is considered to be the most important approach to make national forest stands more vital and stable and to safeguard their functions even under changing climatic conditions. However, due to the dynamics of climate change and the long development cycles of trees, it is still uncertain which tree species are particularly suited for maintaining the different forest functions and which measures will prove to be sustainable in the long term. While several native tree species are increasingly subjected to drought stress and suffering damage, non-native species (neophytes) are sometimes viewed in a critical light because of ecosystem risks (uncontrolled diffusion, changes in nutrient cycles, competition for resources).

Near-natural forest conversion is a complex field of action that encompasses different, sometimes conflicting goals (nature conservation and species protection, climate protection and adaptation to climate change, sustainable use of resources, etc.), different levels of action as well as options for measures to be taken. Moreover, it requires a long-term, strategic approach. Heterogeneous ownership structures and management sizes as well as different utilisation interests and partly limited financial options for action of the owners are additional challenges. Altogether, whether the near-natural restructuring of forests – which is likely to be a permanent task – succeeds in the long term depends to a large extent on how the economic and political framework conditions are designed.

Objectives and approach

The project is intended to analyse the forestry-related, technical, economic and legal aspects of near-natural forest restructuring – including regulatory control options. This requires a content-related perspective that focuses not only on climate-resilient tree species, but also on forest ecosystems. The reason is that the success of a forest restructuring must ultimately be measured by the stability and climate resilience of the resulting ecosystems. The resulting TAB report is intended to cover the following core aspects:

• Overview regarding the state of knowledge on possible impacts of the climate change on forests in Germany
• Overview regarding the state of knowledge on climate resilience of different tree species and forms of mixed forest at different locations
• Overview of requirements for the creation and management of climate-resilient forest ecosystems
• Overview of innovative technologies for near-natural forest management
• Overview of regulatory and economic control options for near-natural forest restructuring

Project progress

By the end of 2022, three expert reports were commissioned on the following topics:

1. Requirements for near-natural forest conversion from a forest science perspective 
2. Technical innovations for forest conversion and sustainable forest management
3. Economic aspects of near-natural forest conversion.

The expert reports have been evaluated and used together with the results of further research to prepare the final report. The final report is currently in the process of approval by the TA Rapporteur Group.