NEIGHBOR RELATIONS WITHIN A COMMUNITY OF EPIPHYTIC LICHENS AND BRYOPHYTES

The nearest neighbor relations of the cryptogams growing on Quercus ru bra in Michigan were investigated over whole tree trunks, and over fou r subsections of trunks to partially eliminate the effects of microhab itat. At all scales numerous nonrandom associations were found, indica ting that it is not only gross microhabitat requirements that determin e these relationships. The associations were found to differ from plac e to place on the tree trunk. Despite sharing the same general habitat (the tree trunk), or part of the habitat (e.g., upper north side), so me species and groups of species are rarely neighbors, whereas others are far more likely to coexist and therefore interact.