The black locust (Robinia pseudoacacia) [1] was brought to Europe about 400 years ago [2]. It is considered currently crucial for biodiversity, especially for insects, bees etc. due to early bloom in spring. It also adds atmospheric nitrogen through root bacteria and improves bad (sandy and eroded) soil. It is one of the most important hard woods in Europe these days for outside constructions, due to its resistance against rot, without requiring impregnation.

This is not common, however. Most invasive species shift the balance in local ecosystems and the common outcome is a lesser diversity of species, with more aggressive ones winning. Natural biodiversity drift does not have the same impact, as it occurs more slowly than human propagation of species.

[1]: https://en.wikipedia.org/wiki/Robinia_pseudoacacia

[2]: https://de.wikipedia.org/wiki/Gew%C3%B6hnliche_Robinie#Einf%...