Senecio pseudoarnica Less. (Asteraceae): a new non-native species invading coastal areas in arctic and subarctic Europe

We report the human-assisted spread of Senecio pseudoarnica , native to the northern coasts of North America and the Far East, to arctic and subarctic regions of Europe. Our findings indicate that the species, imported as a decorative plant, is currently rapidly spreading along coastal areas of Iceland and Norway. An exponential model comprehensively explained the increase in the number of known localities. Close climate matching between the native and non-native ranges, as well as practically exact environmental matching, are the main factors that facilitate the process of naturalisation and invasion. It is likely that a complete eradication of the species is already impossible, and further studies are needed to guide effective management strategies.