The two valley sides contrast greatly. On the south-facing side (adret), the limestone slopes present sparse vegetation. You will find box, shadbush (Juneberry) and common juniper – species belonging to the plants associated with downy-oak groves and Scots pine forests. These slopes, which are mostly covered by short-grass prairie, serve as sheep pastures. You will also see orchids in a thousand different colours and shapes. On the north side (ubac), on the foothills of Le Puech Pounchu, the ground is chalky and forms an island that has been detached from the Causse Méjean by the active erosion of the river Jonte in contact with siliceous soils. This side has been reforested with black pines, a species that is well-adapted to the poor dry soil. It had originally been wooded before the replanting, but over-exploitation of the forest and over-grazing suppressed those woods in the 19th century.