Map notes
This map displays observations of selected invasive plant species in and around the city of Karlsruhe. The data is crowdsourced from iNaturalist, a global citizen-science database.
Invasive plants, also known as neophytes, are species that have been introduced to a new area and spread aggressively, often outcompeting native vegetation and disrupting local ecosystems.
The specific species shown on the map were chosen in collaboration with Prof. Filipa César and Atelier Schaft, based on their workshop 'Material Alchemy: Crafting your samples' at the Living Library in June 2025.
Selected invasive species:
- Impatiens glandulifera (Drüsiges Springkraut / Himalayan Balsam)
- Reynoutria japonica (Japanischer Staudenknöterich / Japanese Knotweed)
- Heracleum sphondylium (Wiesen-Bärenklau / Hogweed)
- Solidago gigantea & S. canadensis (Riesen- & Kanadische Goldrute / Giant & Canadian Goldenrod)
- Ailanthus altissima (Götterbaum / Tree-of-Heaven)
A noticeable pattern emerges from the data: many of these invasive plants are concentrated along Karlsruhe's rivers, the Alb and Pfinz. This is because waterways often act as natural corridors that facilitate the spread of seeds and plant fragments.
Important: Some invasive species are poisonous, and local regulations may prohibit you to harvest or remove them. For more information, please contact the City of Karlsruhe Forestry Office (Forstamt).
Jaap Knevel
References
- Bauer, T. et al. (2021) ‘Differing impacts of two major plant invaders on urban plant-dwelling spiders (Araneae) during flowering season’, Biological Invasions, 23(5), pp. 1473–1485. Available at: https://doi.org/10.1007/s10530-020-02452-w.