Have you ever walked through a hidden pocket of wilderness nestled within a bustling city? Welcome to Glühwürmchengrund und Immenweide a true Berlin secret. These small areas are remnants of a broad peat bog along the Havel River. This is part of Berlin’s ancient river valley. Imagine a landscape of alder swamps and rich peat. The top layer of soil is fertile. Below lies a meter of slightly decomposed brown moss peat. This peat contains remnants of bogbean seeds. This indicates a once mesotrophic environment. Its formation is linked to a medieval rise in the water table. This was caused by the Spandau mill dam. Similar peat bogs formed in the backwater area of the Spandau mills. This includes the Bollenfenn in Tegel.
Glühwürmchengrund und Immenweide were once richer in biodiversity. However the groundwater level has fallen due to drinking water extraction. Parts of the moor have dried out. The Spandau nature conservation authority aims to rewet the area. They plan to lay a pipeline to the Havel River. This will prevent further decomposition of the peat. This will also improve the habitat for amphibians.
Until then apprentices from the Green Spaces Office are busy. They remove competing plants that don’t belong in the moor. They also thin out the alder growth. The NABU Spandau district group supports this work. We also carry out litter collection campaigns. One highly attended event took place on May 5 2019.
A protective belt is being created around the moor. For ten years now adjoining gardens have been left unplanted when vacated. This process may take another ten years. Eventually only areas outside the protective belt will be accessible.
The NABU Spandau district group is transforming former gardens on Wildunger Weg into an insect meadow. Since last November they have been removing Canadian goldenrod a highly invasive plant. This plant has spread rapidly. Canadian goldenrod displaces native plants and offers no ecological value for insects. The area also has snowberry bushes. These are ornamental shrubs from North America also known as snowberry. Because the soil is sandy and sunny they are creating a dry grassland. A 50 square meter area will be sown with a mixture of native wildflower seeds this autumn. The Wildtier Stiftung Berlin kindly provides the seeds. As part of the Urbanity and Diversity project they’re receiving 26 different native wildflowers. These will be planted in autumn. More rainfall is expected by year’s end. This gives the plants a better chance of thriving.
Besides the insect meadow nesting opportunities for wild bees are being created. They are making broken edges and open sandy areas. They are also creating piles of dead wood and stones. They are providing nests for bumblebees and insect hotels. So next time you’re in Berlin remember this hidden jewel Glühwürmchengrund und Immenweide. A testament to nature’s resilience and the ongoing efforts to preserve Berlin’s unique natural heritage.