Increased forest vulnerability is being reflected as more widespread and severe drought-induced decline episodes. In particular, the Mediterranean area is revealing a high susceptibility to phenomena of loss in tree vitality across species. Within tree species, oaks (Quercus spp.) are experiencing extensive decline in many countries. However, in the wake of the so-called “oak decline phenomenon”, the attention on these species has generally been limited. In this paper, we review the current available literature on oak-decline cases reported within the Mediterranean Basin, with particular remark for those occurred in Italy and Spain. More specifically our main aims were to: (i) provide an update on the patterns and mechanisms of decline by focusing on tree-ring and wood-anatomical variables; (ii) provide some hints for improving the resistance and resilience of oak stands experiencing decline. Our review reveals that drought is reported as the main driver triggering oak decline within the Mediterranean Basin, although other causes (i.e., increasing temperature, pathogens attack or excessive stand density) could exacerbate decline. In most reported cases, drought induced a substantial reduction of growth and changes in some wood anatomical properties. Indeed, growth decline prior death is also indicated as an early-warning signal of impending death. In ring-porous oak species, declining trees were often characterized by a very low production of latewood and a decrease in lumen area of the widest earlywood vessels, suggesting a potential reduction of hydraulic conductivity. Moreover, hydraulic dysfunction is reported as the main cause of decline. Finally, regarding management actions that should be considered for improving the resilience of declining stands and preserve the species-specific stand composition, it could be useful to shorten the rotation period of coppice stands or promoting their gradual conversion towards high forests, and favoring more drought-resistant species should also be considered. In addition, regeneration prior to regeneration cuts should be improved by anticipating seed dispersal or by planting oak seedlings obtained from local germoplasm.

We present the results of a dendrochronological study carried out on timbers from the monastic abbey Grancìa of Brindisi di Montagna in Southern Italy. Our objective was to date cross-sections of oak (Quercus spp.) taken from structural timbers to determine the felling dates, the time span covered by the series and to evaluate whether the retrieved tree-ring data could be used to extend an existing living trees chronology of oak from Southern Italy. Dendrochronological analyses were performed on samples collected from eight oak timbers in 2006 during the restoration of the abbey. Raw tree-ring series were crossdated and grouped into a floating chronology that was compared with an absolute reference chronology, specifically constructed from living Quercus pubescens (Willd.) trees, from the nearby Pollino National Park. Seven of eight samples could be absolutely dated in the early 19^th, late 18^th and mid late 17^th Centuries, providing a chronology that reaches back to AD 1545.