Corticolous moss and liverwort species in young, man- aged Douglas-fir stands show pronounced directional differ- ences in abundance on tree stems and a preponderance of positive spatial associations among species. Corticolous mosses also appear to be negatively affected by silvicultural thinning, the opposite of the response observed for under- story vascular plants. We suggest that these patterns point to the importance of microclimate and drought limitation in de- termining the amount and diversity of corticolous bryo- phytes in managed stands, in contrast with light limitation of vascular understory plants. Our results imply that stand in- terventions appropriate for enhancing abundance and diver- sity of one guild of organisms (e.g., vascular understory plants) can potentially reduce abundance and diversity of other guilds (corticolous bryophytes). Such differences in re- sponse illustrate the importance of examining management impacts on little-studied organisms such as corticolous bryo- phytes, and also the challenge of effectively managing for- ests to maintain diversity of all organisms