The vegetation dynamics of non-vascular epiphytes following conversion of primary forest due to clearing by humans was investigated. An inventory of the epiphyte communities on twelve canopy emergent trees was conducted in primary and 35 year-old secondary tropical montane cloud forest in Costa Rica. Sampling included tree trunks, large branches, and the small branches and twigs of the outer canopy. Six Conostegia oerstediana were studied in secondary forest, and three Meliosma vernicosa and three Ocotea tonduzii in primary forest. Mosses, hepatics and lichens were surveyed in 256 replicate 30cm cylindrats. Substrate characteristics were measured, and the percent cover of each species was estimated using phytosociological methods. A reconnaissance for additional species was conducted in the canopy, on the trunks, and from recently fallen branches. Quantitative analyses of the community composition, relative abundance, distribution, and epiphyte species diversity of the two habitats are discussed. Only data for the mosses are presented, as identifications of hepatics, marco- and crustose lichens are currently underway.

Key words: Costa Rica,disturbance,diversity,epiphytes,moss,tropical cloud forest