Knut Sturm, from the Natural Forest Academy, participated in the BEECH POWER workshop that took place on 24th-25th of March, by presenting a case study of silviculture management in the forest of Lübeck, in Norther Germany.
A new way of forest management
In 1990-1994, a silviculture system was developed in cooperation with some of the biggest nature conservation NGOs in Germany. The goal of this new system was to create a “nature forest” with low input forest management. In other words, allow the forest to follow its own ecological processes to achieve a dynamic ecosystem rather than a stable forest structure – a randomly multivariate succession mosaic.
To see what a “nature forest” actually is, they left 11% of the forest unmanaged to serve as reference for the managed areas. Therefore, the goal is that the managed areas should look almost identical to the reference areas.
To achieve this, they forbid different practices like clear-cuts, monocultures, application of pesticides and fertilizers, drainage of soils, feeding wild animals, skidding activities outside of the skidding system or introduction of exotic tree species. Indeed, they never plant any trees, but leave natural regeneration to take place. Further, they don’t allow forest activities outside of the natural disturbance regime of the forest ecosystems.
Key indicators were measured every five to ten years. These include standing volume (including habitat trees and dead wood), species composition (including different succession stages), gap dynamic, structure of the vegetation and tree layers, and indicator species.
Results form “nature forest” approach
Until now, the results are very promising, with increasing biodiversity levels. Some examples include the presence of one pack of wolfs, the increased population of otters and the first colonization of bechstein’s bats, sea eagles and black storks. Further, the population of some typical old growth forest birds like the middle-spotted woodpecker and the red-breasted flycatcher are also increasing. Similarly, standing volumes of tree species like beech and oak are increasing. In contrast, exotic trees like larch are slowly reducing in relation to native species.
Interestingly, by following this “nature forest” approach, they reduced drastically the costs and the sold wood in cut, while the forest estimated value has increased. This is possible because the timber volume and growth has increased, growing timber’s economic value.
Finally, Lübeck’s public is happy too. Through a survey to see social acceptance and expectations of the forest, the majority of responders gave a low value to wood production and the economic situation of the forest. In contrast, the great majority expected the forest to provide habitat for animals and plants, and protection for soils, water and climate.