Monitoring two REINFFORCE Network Arboreta: First result on site, climate and genetic interaction showing impact on phenology and biotic damages

Abstract

Understanding how climate affects tree phenology, biotic and abiotic vulnerability, is a most important research subject. Particularly, climate warming appears to lengthen the growing season, which may affect the exposition to insect pests and pathogens. Also, extreme weather events combined with shifts in phenology may have dramatic consequences, such as early leaf flushing exposure to freezing events. In this study 2 arboreta were followed in the south most distribution of the REINFFORCE Network (Lisbon and Sintra) for 3 species, one native (Quercus robur L.) and 2 non-native (Quercus rubra L. and Betula pendula Roth). Plant growth, leaf phenology and insect damage were assessed according to protocols defined under REINFFORCE project. Species x site interaction was found significant for survival and growth. Phenology differed between and within all species. No difference found for frost tolerance. B. pendula had earlier bud burst at both sites, resulting in a longer growth period, and higher stem growth, being least affected by insect damage, although survival was affected under higher temperature, where Q. robur performed better. This study corroborates the importance of REINFORCE arboreta network as a tool to assess climate change impact on forest species and support assisted migration considering climate change scenarios.