Microhabitat Affinities of Missouri Ozarks Lichens

Abstract

The lichen communities of nine mixed-hardwood sites in the southeastern Missouri Ozarks were characterized from sampling of the ground layer, tree-bases, midboles, and canopy branches. Of the 181 lichen taxa documented, the majority were crustose (55%) or foliose (32%) lichens. Only a quarter (26%) of all species occurred across all four microhabitats, with the majority of dominant taxa demonstrating apparent preferences for a single (38%) or multiple (27%) microhabitat, a given host tree species (17%), or a particular ground substrate (12%). High diversity of ground substrates and a large amount of presumed litterfall in the ground layer were of particular note. Relative species composition and abundance of lichen communities differed in stands with overstories dominated by red oak species as opposed to white oak species, but showed only suggestive variation with aspect class, geology, bedrock, landform, and soil type. Lichen diversity measures were also weakly associated with the presence of individual white or red oak species in the overstory, but no clear patterns appeared with respect to white or red oak subgroups. Stratification by microhabitat and host species would be necessary in future experimental studies in this region.