Recent phytosociological data on the forests of Thierache (department Aisne, France). I - the mesophilous forests of clayey-calcareous Thierache

Thierache is a small natural region with a bocage and forest landscape whic h takes up the north-eastern corner of department Aisne. Forest vegetation has been studied according to the synusial phytosociological methodology. I n this first part the author presents the phytosociological data for mesoph ilous forests of clayey-calcareous Thierache. Four arborescent associations , three schrubly associations and seven herbaceous associations with their synfloristic and synecological characteristics are described. The main phyt ocoenosis are then reconstructed.