We examined if the spatial distribution of epiphytes in a forest stand differs between two sexually and three asexually dispersed species. As study species we have chosen two sexually dispersed species, the lichen Collema curtisporum and the bryophyte Orthotrichum speciosum, and three asexually dispersed species, the lichens C. furfuraceum and Leptogium saturninum and the bryophyte O. obtusifolium. All of these species grow on Populus tremula. In P. tremula stands, individual trees may be regarded as distinct patches for the studied species, while the stand represents a ‘landscape” of discrete patches. The study was performed in two relatively homogeneous forest stands. The study revealed that the asexually dispersed species were more common than the sexually dispersed. It was also shown that the sexually dispersed species were more aggregated than P. tremula in both stands. In contrast, the distribution of the asexually dispersed species mirrors, more or less, the distribution of their host, i.e. the spatial pattern shown by P. tremula. It is unlikely that the measured environmental variables strongly influenced the observed spatial distribution. Thus, we suggest that the different dispersal and establishment strategies were important in shaping the local distribution of the species.

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