The whole Val di Farma, and in particular the stretch within the Reserve, preserves unique naturalistic aspects for the province of Siena and some of the most interesting ones of the whole Italian peninsula. The particular conformation of the valley is at the origin of a showy phenomenon of thermal inversion leading to the particular microclimatic conditions characterizing the bottom of the valley, colonized by Beech tree, Sycamore, and even Birch, typical plants of higher altitudes. The fauna of the Reserve includes particular species, such as the Alpine Newt of the Apuane, the Spectacled Salamander, and the Agile Frog, amphibians which only live in Italy.