A forest owned by the Tuscany Region, known since the Middle Ages because it was reserved for cutting for the wood supply of the Volterra saltworks.

At Decimo, deciduous broadleaf woods dominated by Turkey oaks with good vertical development alternate with Mediterranean evergreen sclerophyllous scrubland and a fragment of lowland forest typical of hilly valley floors with southern ash and white hornbeam.

The forest includes all the most typical fauna of the woods in this area, ungulates such as wild boar and roe deer are common, so even their main predator, the wolf, seems to frequent the area assiduously thanks to the extension of the forest and the scarce anthropic disturbance.