Memoria para optar al título profesional de: Ingeniero en Recursos Naturales Renovables / Richness and composition floristical characters of the high-andean vegetation were evaluated among a site in the Coastal (Altos de Chicauma) and Andes (Quilapilún) mountain ranges of central Chile (33º S). The dispersal spectrum of the total floras and the proportion of Chaetanthera species with different pappus types were compared among sites, in order to discern the relevance of the dispersability degree in the origin of the analyzed vegetation in the Coastal mountains. Both richness and composition of species, evaluated in equivalent areas, are not significantly different, although there is a higher proportion of species only present in the Andes than in the Coastal range of central Chile. The dispersability is similar among sites, indicating a low probability of long distance dispersal as the origin of the actual high-andean vegetation in Altos de Chicauma. Aspects relevant to explain the resulting richness and compositional patterns, and the evolution of the high-andean flora, are discussed.