THE REGENERATION OF PURE Juniperus excelsa M. Bieb. STANDS IN PRESPA NATIONAL PARK IN GREECE

Juniperus excelsa M. Bieb is a species with growth plasticity that is capable of growing in harsh abiotic environments as well as in severe biotic conditions. In order to analyze the regeneration off. excelsa pure stands in Prespa National Park of Greece and to determine whether regeneration in gaps or under facilitation of nurse plants dominates, ninety sample plots were established in two site types and six structural types. In each plot, all J. excelsa regeneration plants were graded in 2 categories. The first category represents the seedlings that have been established and grew under the facilitation of other plants, while the second category refers to seedlings that are found in canopy gaps without significant side shade. Facilitation does not dominate in the regeneration process of J. excelsa in Prespa National Park. On the other hand, this does not mean that regeneration in gaps predominates. Even though facilitation is not the dominant process in the regeneration of J. excelsa in Prespa National Park, a significant number of regeneration plants have been established under the facilitation. Site productivity seems to affect the process of facilitation. It seems that the process of grazing through trampling and animal tread determines the regeneration process of the species that can be established and grow either in light or under shade. J. excelsa can be a very interesting candidate species for restoration of degraded lands.