European ornamental garden flora as an invasion debt under climate change

1.Most naturalized and invasive alien plant species were originally introduced to regions for horticultural purposes. However, many regions now face an invasion debt from ornamental alien species, which have not yet naturalized. In this regard, climate change represents a threat as it may lower the barriers to naturalization for some ornamental alien species. Identifying those species is extremely important for anticipating impending invasions.

2.To identify predictors of naturalization, we modelled the effects of climate, nursery availability and species characteristics on the current European naturalization success of 2,073 ornamental aliens commonly planted in European gardens. We then used the resulting model together with climate projections for 2050 to forecast future naturalization risks for the 1,583 species not yet naturalized in Europe.

3.We found that non‐European naturalized range size, climatic suitability, propagule pressure, having a dioecious sexual system and plan...