I am a Professor of Microbiology at South Dakota State University, where I lead a group on bacterial ecophysiology, and teach bacteriology, molecular biology, and scientific writing. At FABI, I am involved in the Systematics and Evolution of Symbiotic Nitrogen-Fixing Bacteria research group (CPHB).

Bacteria function and interact very well in soil, maintaining large populations. I seek to understand how bacteria function and interact in these spaces that have never seen an agar surface. Soils receive sporadic or seasonal input of organic carbon, so soil bacteria likely evolved to preserve resources for long-term population maintenance. The well-known faster growing taxa such as Pseudomonasor Bacillusrely on nutrient hot spots such as growing roots that exude organic carbon. Successful population maintenance under nutrient limiting, competitive conditions should include the development of both co-operative and competitive mechanisms. Networks of cooperating bacteria may contribute specific functions such as fixing atmospheric nitrogen. Conversely taxa in competition would exert deleterious factors without expending excessive energy. To address these questions, we study soil bacteria under soil-mimicking conditions, based at South Dakota State University and University of Pretoria.