My teaching and research focus on ecology, global environmental change, and the sustainability of managed and unmanaged terrestrial ecosystems. Our research attempts to find the rules that regulate patterns and processes at multiple scales, and the mechanisms that explain them. Doing so often involves integrating from physiological to community to ecosystem ecology. We work primarily on the forests and grasslands of mid-North America as well as globally on terrestrial ecosystems in aggregate. This includes unique experimental field studies of global change effects on grasslands and forests; synthetic analyses of global plant trait data; and the development of physiologically robust global carbon cycling models. Over the years I have been deeply involved in the search for universal rules about leaf design and related scaling of physiology from seedling to adult, from cell to ecosystem, and from stand to the globe. Current projects include the B4Warmed Experiment that is assessing the effects of experimental warming on boreal forests in northern Minnesota and the BioCON study of biodiversity, carbon dioxide, nitrogen, and water impacts on the functioning of perennial grasslands in central Minnesota. Potential graduate students are encouraged to contact me directly by email.