Established Invasive Tree Species Offer Opportunities for Forest Resilience to Climate Change

A rapidly changing climate is weakening the resilience of forest ecosystems through vitality loss of major native tree species, which reduces the ability of forests to deliver ecosystem services. Established invasive tree species (EITS) may take over the vacant space potentially preventing the regeneration of the preferred native tree species. This paper aims to investigate how expansion of these invasive non-native tree species can be addressed in a context of climate-smart forest management, considering alternatives to costly and often ineffective EITS control measures. We found that forest ecologists increasingly recognize that climate-smart forest management, in particular tree species diversification and close-to-nature forest management, can strengthen the resilience of forests against negative impacts by EITS. In the resulting resilient forest ecosystems, a more closed canopy may deprive EITS of their invasive nature, and EITS may contribute to climate change adaptation. This review proposes new pathways for forest management transcending the apparent incompatibility between the dominance of EITS and the adaptation capacity of forests and forest management to climate change. Adaptive measures to increase the resilience of forests to climate change may prevent the dominance of EITS. Under such conditions, useful functional traits of these tree species may even contribute to maintenance or enhancement of biodiversity, provisioning of ecosystem services and adaptation to climate change.