I work in three overlapping, interdependent areas Tools for analysis of ecological communities and habitats: My research on analytical tools concerns how species abundance as a response variable differs from the ideal variables, how this creates problems, and how to deal effectively with those problems. My current research in this area focuses on species response surfaces in multidimensional predictor spaces and on nonparametric multivariate tools for community analysis. Ecology of temperate forest epiphytes: My work in this area include basic research on the distribution, abundance, and dispersal limitations of temperate forest epiphytes (lichens and bryophytes) and applied work on how changing forest practices, air quality, and climate will alter lichen communities in our future ecosystems. We have studied the long-term consequences of green-tree retention, how different species and functional groups of lichens are distributed in young, seemingly monotonous forests, and whether the structure of young forests be changed to enhance the re-entry and development of old-growth associated epiphytes. Biodiversity of lichens: I combine DNA sequences, morphological, and secondary metabolite data to improve our understanding and taxonomy of lichen biodiversity in the Pacific Northwest and the World. My work on regional lichen floras has facilitated work on the ecology and biodiversity of lichens in the Pacific Northwest. Regional floras for macrolichens, microlichens, and common mosses, have been completed. In-depth studies of particular groups include Aspicilia, Cladonia, Hypogymnia, Lecidea, Rhizocarpon, Stereocaulon, and Umbilicaria are ongoing.