My major focus is on the roles of fungi in the environment, in particular mutualistic soil fungi that are essential for the healthy growth of most terrestrial plant species. My varied research topics mirror the diversity of fungi as a group and the many functional roles that they carry out in most ecosystems. A key aspect of my work is the detection and identification of fungi in environmental samples. Since even those species that produce visible structures above ground can present considerable problems for identification, a significant part of the research is focused on the development and use of molecular tools for accurate species identifications. These tools are also used to examine spatial structuring of populations and communities at both local and continental scales. I have written over 85 papers for international journals.