This study reviews the impacts of climate change on Greek forests, analysing factors such as climate trends, forest management, biodiversity, genetics, insects, and wildfires, using data from the Scopus and Mendeley databases and official reports. By utilising our current understanding and allocating necessary efforts and resources, we actively address climate change consequences on forests. This study focuses on climate change and extreme weather outcomes on forests. Greek mountain forests at 520–1310 m experience decreasing annual mean and minimum temperatures (−0.015 and −0.027 °C yr^–1) but increasing maximum temperatures (+0.014 °C yr^–1), especially in Southern Greece (+0.047 °C yr^–1). Recent findings reveal forests migrating to higher altitudes with favourable conditions, correlating with water availability, temperature, and tree growth, necessitating further research on forest productivity. A decline in fir tree-ring growth (Average Tree Ring Width Index < 0.6) is observed in mainland Greece, indicating temperature’s effect on growth. Effective forest tree conservation requires prioritising biodiversity monitoring, considering climate change impacts on phenology and addressing the absence of strategies to protect and enhance genetic diversity. Climate change influenced 70 forestry pests’ ranges, notably among Greek insect pests. Annual burned areas from forest fires data indicate a consistent long-term increasing trend, underscoring fire prevention prioritization and exploring fire risk, behaviour, and climate change. The study highlights two to four significant knowledge gaps, and one to three key challenges pertaining to the six research areas. Finally, it promotes partnerships for informed decision-making and better outcomes by integrating Indigenous knowledge, scientific understanding, and collaboration among research, policy, and local management.

Beech forests play an important role in temperate and north Mediterranean ecosystems in Greece since they occupy infertile montane soils. In the last glacial maximum, Fagus sylvatica (beech) was confined to Southern Europe where it was dominant and in the last thousand years has expanded its range to dominate central Europe. We sampled four different beech forest types. We found 298 insect species associated with beech trees and dead beech wood. While F. sylvatica and Quercus (oak) are confamilial, there are great differences in richness of the associated entomofauna. Insect species that inhabit beech forests are less than one fifth of those species living in oak dominated forests despite the fact that beech is the most abundant central and north European tree. There is a distinct paucity of monophagous species on beech trees and most insect species are shared between co-occurring deciduous tree species and beech. This lack of species is attributed to the vegetation history and secondary plant chemistry. Bark and leaf biophenols from beech indicate that differences in plant secondary metabolites may be responsible for the differences in the richness of entomofauna in communities dominated by beech and other deciduous trees.

First record of Leptoglossus occidentalis (Heteroptera: Coreidae) in Greece