Identifying plant communities of thermophilous deciduous forest in Greece: Species composition, distribution, ecology and syntaxonomy

Thermophilous deciduous forest is widespread in northern mainland Greece and extends in patches further south to Peloponnisos and the bigger islands. In this paper, we provide a phytosociological survey of the plant communities of deciduous oak and mixed forest throughout Greece, based on about 370 releves from the literature and more than 300 personal unpublished ones. Assocation names of the thermophilous deciduous forest are re-evaluated, and syntaxonomic conclusions added. The releves are classified, and 13 associations and several additional subtypes described and presented in synoptic constancy tables. The following associations were recognized, and characterized by species composition, ecology and distribution: 1. Phillyreo-Carpinetum orientalis, 2. Dryopterido pallidae-Ostryetum carpinifoliae, 3. Tilio tomentosae-Castanetum; 4. Genisto carinalis-Quercetum petraeae, 5. Querco frainetto-Castanetum, 6. Cytiso villosi-Castanetum; 7. Lathyro laxiflori-Castanetum; 8. Symphyto ottomani-Quercetum frainetto, 9. Verbasco glabrati-Quercetum frainetto; 10. Huetio cynapioidis-Quercetum frainetto; 11. Digitali viridiflorae-Quercetum frainetto; 12. Geranio asphodeloidis-Quercetum frainetto; 13. Oenantho pimpinelloidis-Quercetum frainetto. Associations 1-2 are assigned to the alliance Fraxino orni-Ostryion, 4-6 and 8-13 to the Quercion frainetto (both Quercetalia pubescentis), 3 interim to the Tilio-Acerion, and 7 to the Quercetalia ilicis. The two Quercetalia pubescentis alliances co-occur in northern Greece; their habitats differ chiefly in terms of soil conditions, bedrock and topography, rather than in overall climatic character.