A total of 546 releves collected in western Bulgaria and referred to Festuco-Brometea were classified into the alliances Festucion valesiacae, Saturejion montanae, Cirsio-Brachypodion pinnati and Chrysopogono-Danthonion calycinae. All releves assigned to alliance Cirsio-Brachypodion pinnati were further classified towards lower level which resulted in the description of a new association - Hieracio pilosellae-Festucetum dalmaticae and two new subassociations added to ass. Galio lovcense-Artemisietum chamaemelifoliae. Both associations were ecologically well differentiated on the basis of soil parameters (pH and humus content) as well as some additional factors (exposition, land use, etc.).
This study deals with the diversity of forest vegetation in the Slivenska Mountain (Eastern Stara planina) and presents a contemporary classification scheme for the identified syntaxa. A total of 137 relevés were collected and analyzed using specialized software (JUICE 7.0 and PC-ORD Version 4). As a result, forest vegetation is classified into 10 associations, 3 subassociations, 4 variants and 5 communities They belong to 7 alliances, 5 orders and 3 classes: Carpino-Fagetea sylvaticae, Quercetea pubescentis and Alno glutinosae-Populetea albae. The recorded 18 distinguished vegetation groups show a relatively high diversity of forest plant communities of the study area.