We studied the phytosociology, ecology and biogeography of the Dinaric fir-beech stands (Omphalodo-Fagetum) in the Trnovski gozd plateau, at the north-western part of the Illyrian floral province. We identified and confirmed two geographical variants (var. geogr. Saxifraga cuneifolia - central and western part of the plateau, and var. geogr. Calamintha grandiflora - eastern part of the plateau), and 10 floristically and ecologically well differentiated subassociations (-rhododendretosum hirsuti,-saxifragetosum cuneifoliae, -adenostyletosum glabrae, -festucetosum altissimae, -calamagrostietosum arundinaceae, -stellarietosum montanae, -seslerietosum autumnalis, -calamagrostietosum variae, -sambucetosum nigrae and -asaretosum europei). The most frequent stands bellong to the subassociation