Climate Adaptations and Challenges of Non-native Tree Species in Forest Ecosystems

Introduced tree species represent a significant proportion of the total dendroflora of the World, although their contribution to forest habitats is usually marginal. The decline in the condition of native tree species observed in recent years is increasingly jeopardizing the provision of forest ecosystem services in many regions worldwide. This decline in tree vitality, largely due to global change, is prompting scientists and policy makers to question the extent to which introduced non-native tree species over the last few hundred years have adapted to the new environmental conditions. The adaptive potential of non-native tree species seems even more worth exploring, as some of them are highly invasive and pose a threat to the biodiversity of native habitats, often competing with native species.

To understand the adaptive potential of non-native trees, it is necessary to follow their growth and physiological adaptations through their ontogenetic development. Since environmental and especially climatic conditions can change considerably over time, such assessment requires either a retrospective analysis of growth and physiological processes, including dendrochronological analyses and long-term monitoring of reproductive processes. Common garden experiments are invaluable for understanding the dynamics of adaptation of tree species and populations and allow the assessment of their phenotypic plasticity. When determining the adaptation of non-native species in the context of their suitability for forestry in their secondary range, it is crucial to address intraspecific variability, especially for species with a wide ecological range of their native distribution.

This Research Topic welcomes studies addressing all aspects of growth and physiological adaptation of introduced trees in temperate, boreal, and tropical forests of the northern and southern hemispheres, such as:

• The climate sensitivity of introduced woody plants: trees and shrubs.
• The adaptation of secondary growth of phylogenetically close non-native and native trees.
• The effect of extreme climate events on physiology and radial growth of non-native trees.
• The intraspecific variation in growth and xylem formation of introduced tree species.
• The long-term monitoring of growth and leaf development in secondary distribution.
• The secondary growth of introduced species in urban forests
• The impact of diseases on the growth of non-native woody plants in their secondary distribution
• The competitive strategies of non-native tree species against native species.