First report of Gymnocoronis spilanthoides in France
Gymnocoronis spilanthoides (Asteraceae: EPPO A2 List) is native to South America and recorded as an invasive alien species in Australia, New Zealand, Japan, China, and Taiwan. Within the EPPO region, G. spilanthoides has been recorded in Hungary in canals connected to thermally influenced waters, in Italy (North-Western Lombardy region) and the Netherlands in Vleuten in 2019. A population of G. spilanthoides was recorded for the first time in North-West France (Le Mans) along the river Sarthe in 2021. The population in August 2022 was flowering and covering a total area of 50 m2. It is unknown how the population arrived in this location, but possible pathways include as a contaminant on boats or machinery or attached to migratory birds. Managing this population should be a priority and manual control can be successful in reducing small infestations either by hand removal, raking or drainage machinery. Plants can be disposed of by drying and burning. Care should be taken to ensure that all plant parts are removed to avoid fragments that can regenerate.
Sources
Tela-botanica.org (2022) Gymnocoronis spilanthoides, asteracée nouvelle pour la France. Available at: https://www.tela-botanica.org/2022/08/gymnocoronis-spilanthoides-asteracee-nouvelle-pour-la-france/