SUMMARY
This study was carried out on all the Etna beech distribution area and consists of a phytosociological analysis. Moreover data relating to various pysiognomical and structural aspects was collected from 12 sample areas selected on the different expositions of the volcano. From the phytosociological analysis it emerged that it is very difficult to define the Etna beech forests syntaxonomically: in most cases it can be seen that they belong to the class Querco-Fagetea, but it is not always possible to identify the association, the alliance and the order. Some communities seem to belong to the Quercetalia pubescentis rather than to the Fagetalia sylvaticae. Other communities do not even belong to the class Querco-Fagetea. These are in fact relict forests surviving in extreme life conditions. They are at the southern limit of its distribution area and are subject to unfavorable environmental conditions: a volcanic substrata, the Mediterranean climate, the high level of man’s intervention. The study of the tree and stump density, stem diameter, basal area, litter cover and litter thickness and seedling density, carried out on 12 sample areas, shows that these forests have a very variable physiognomy and structure. The forests with a more balanced physiognomy and structure are made up of forests with high trunks of different ages. The seedling density, correlated with the litter thickness and cover, was found to be significant in areas located on the east side of Etna, where there are better light conditions and greater rainfall. This study brought to light the presence of a species: Monotropa hypopytis L. not previously reported as having been found on Mt. Etna.