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[Display omitted] • Four bioclimatic clusters determine black locust distribution in Europe. • The eastern cluster overlaps with climatically suitable area in current and future distribution. • The black locust highlighted spatially and temporally variable climate sensitivity. • The plasticity in secondary growth may increase the black locust's invasive potential. As a consequence of native tree species decline and distribution range contraction in Europe, acclimation of the non-native tree species at the edge of their distribution is gaining importance. Although non-native tree species may provide sustainable ecosystem services, as a potentially invasive species they may be a threat to local ecosystems as well. In Europe, black locust (Robinia pseudoacacia) a non-native species, seems to meet the condition of acclimation as a multi-generational process. The acclimatization, however, may have consequences not only for growth performance but also for the species' invasive potential. This study investigates the spatiotemporal pattern of secondary growth and climate sensitivity among six black locust stands along continentality gradient in Eastern Europe with the respect to bioclimatic conditions of the species distribution in Europe. Despite comparable bioclimatic conditions, climate sensitivity of black locust stands is highly variable, both temporally and spatially. The winter and spring temperatures are a key climatic driver of the growth pattern in southern and western Poland. Growth response to previous winter and current summer precipitation distinguished stands in western and eastern Poland. A significant increase in the mean annual temperature during the last 70 years likely triggered temporal instability of the black locusts' climate signal. In general, drought conditions were found to be the main limiting factor at the edge sites within the black locust gradient. Thus, the climate sensitivity of black locust stands reflects rather site-specific microclimatic conditions then bioclimatically-based clustering pattern. Despite climate-related limiting factors, black locust seems to be characterized by high potential for acclimatization to Eastern European climatic conditions, suggesting high invasive potential. Thus, the replacement of native species by black locust or the conversion of local habitats into monocultures for biomass production should not be recommended, while species management should follow proactive measures to reduce the risk of uncontrolled spread of the species. Divergent growth reaction of black locust stands implies high plasticity of secondary growth and thus high probability of acclimatization to future climate. Given the expected range expansion to the East in Europe, we call for expanding dendroclimatic studies to the areas of future species expansion in order to test its climatic and edaphic limitations. This seems to be crucial for formulating non-native species management strategies in line with sustainable forestry, preventing the uncontrolled expansion of the species that threatens vulnerable habitats. [ABSTRACT FROM AUTHOR]

• Native and non-native pines react uniformly to drought. • Local site conditions diminished interspecific variation. • No evidence that alien pines are better adapted to climate change than native pines. Two European pine species, Pinus sylvestris and Pinus nigra , are experiencing dieback as a result of the increasing frequency and intensity of extreme climatic events. Recent species distribution models predicted shrinkage of ecological niches in the near future and shifted their habitat range towards the northeast. Consequently, P. sylvestris may contract its range and P. nigra may expand in Central Europe. To test whether native pine species have an advantage over introduced pine species in acclimation to a novel climate in Central Europe, we investigated the climate sensitivity and vitality of P. sylvestris, P. nigra and P. rigida. We sampled mature stands of each pine species at three sites in Central Europe, for which we determined climate–growth relationships: temporal stability of temperature and precipitation correlations with tree-ring width and resilience indices. Based on remote sensing data, we assessed differences in surface reflectance and photosynthetic activity obtained from the normalised difference vegetation index (NDVI). Our analyses revealed that the climate sensitivity and surface reflectance of pines are not due to their nativeness in Central Europe but better explained by local site conditions. The specificity and variability of drought events may determine both the homogeneous and diverse susceptibility of species to a negative water balance. Therefore, the character of future climatic extremes seems to be the key to understanding the acclimation of native and non-native pine species in Central Europe. Because our study do not provide evidence of the superiority of non-native pine species over P. sylvestris , and the potential impacts of introduced species on local habitats seem poorly understood in the face of climate change, we urge particular caution in introducing species with unrecognized invasive potential. [ABSTRACT FROM AUTHOR]

• We predicted how alien tree species in Europe will respond to climate change. • Conifers will contract, while deciduous trees will expand climatic niches. • Potential range shifts predicted for 2061–2080, will be observed in 2041–2060. • We provide a novel perspective for forest management and nature conservation. Alien tree species are considered both a threat to nature conservation and a base for forest management. We compiled species occurrences from biodiversity databases, forest inventories, and literature data. We modeled the availability of potential niches using the MaxEnt method and bioclimatic variables for current conditions, 2041–2060, and 2061–2080 periods. We used four climate scenarios: SSP126, SSP245, SSP370, and SSP485. The results confirm our hypotheses that, (i) coniferous species will contract, and deciduous trees will expand their climatic niche, (ii) a significant part of the areas where the studied species currently occur will be outside their climatic optimum in the coming decades; (iii) changes in the climatic optimum distribution will be greater in the 2041–2060 period than in 2061–2080. These predicted shifts are relevant for evidence-based management in sites already occupied by the studied alien trees. Our results are also relevant to the development of prevention and early detection measures in areas predicted to become climatically suitable for the studied species. [ABSTRACT FROM AUTHOR]