EASIN - European Alien Species Information Network
The invasive but useful black locust trees in Europe
The black locust (Robinia pseudoacacia) was first introduced to Europe from North America in the early 17th century and has become part of our cultural and ecological landscape.
The black locust (Robinia pseudoacacia) was first introduced to Europe from North America in the early 17th century and has become part of our cultural and ecological landscape. A fast-growing, pest-resistant tree with attractive flowers, it was planted for both ornamental and commercial forestry purposes. However, it is considered highly invasive. A recent study, drawing on a wide range of previous research, presents the first summary of the black locust’s ecological and socio-economic impacts (focusing on Central Europe).
Evidence shows that, when replacing native vegetation, the black locust reduces local biodiversity, with comparable impacts to those of knotweeds (Fallopia sp.) and giant hogweed (Heracleum mantegazzianum), two notorious invasive plant species. On the other hand, on intensively farmed land, for example, clusters of Robinia increase biodiversity, provide shelter for many plants and animals, and serve as corridors for wildlife movement. Moreover, the species produces valuable water- and rot-resistant timber and firewood, and provides nectar for making high-quality honey. It can also be used to control soil erosion and improve damaged sites, as it is able to tolerate both toxic and extremely dry soils.
However, the black locust’s impact varies significantly according to the local environment and the study suggests that, with careful management, the species could have a sustainable future in which it brings economic benefits without causing undue environmental harm.