An updated checklist of alien plants in the Republic of Korea

We updated the checklist of alien plants in the Republic of Korea by re-examining existing records through field and specimen surveys and incorporating the latest taxonomic and nomenclatural research. The checklist includes 804 taxa, comprising 109 families, 458 genera, 757 species, 14 subspecies, 21 varieties, two formae, and 10 hybrids. Of these, 140 taxa are presumed to have been introduced before 1876, and 644 taxa after that year. When classified based on invasion status, there were 436 casual alien and 368 naturalized taxa, of which 60 were classified as invasive plants. Additionally, when examined for characteristics such as cultivation, distribution, and government management, 381 taxa are cultivated, 38 have not been observed recently and are presumed no longer to occur in the Republic of Korea, and 18 are regulated plants managed for their negative ecological impacts. Furthermore, based on specimen data, the spread level of each taxon was assessed: 117 taxa were classified with a spread level of “notable spread” (NS) or higher. Although most alien plants in the Republic of Korea are currently not invasive, this status may change in the future due to climate change or ongoing human disturbances. Therefore, continuous research and the establishment of management measures to prepare for their potential invasiveness are necessary.