The global cultivated alien flora, its history and its contribution to plant invasions

• Applicant: Professor Dr. Mark van Kleunen
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: since 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 432253815

Most plants that we daily encounter, in our gardens and public green spaces or as escapees in the wild, are alien plants that were brought into cultivation as economic or ornamental plants. However, it remains unknown in which parts of the world which cultivated plant species are grown, and how these cultivated floras are biased with regard to species characteristics, region of origin and phylogeny. Such information is important not only from a historical and cultural perspective, but also because most alien plant species that have become naturalized and invasive are escapees from cultivation. Therefore, one major objective of the proposed project is to build a global database of regional inventories of cultivated plant species, and to analyse this database to test whether there are biases in the cultivated flora with regard to geographical origin, species characteristics, phylogeny and in which part of the world they are cultivated. Moreover, by combining this global cultivated plant database with data on the naturalization success of species, we will test how patterns and biases in the cultivated alien flora affect patterns in the naturalized alien flora. Other major objectives that we will address are how cultivation biases changed over time, and how this affects which cultivated alien species have become naturalized. We will address these two objectives using two unique datasets, one on c. 9000 plant species introduced into Kew Gardens (Great Britain) prior to 1814, and one on the availability of c. 22,000 species and varieties in USA nursery catalogues spanning the period from 1719 to 1939. The proposed project will thus provide the first global cultivated plant database, and important insights into how the cultivated flora and historical changes in its availability relates to the naturalized alien flora.

• DFG Programme: Research Grants