I study plant community structure and dynamics - which plants occur in particular areas (and why others do not) and how (and why) that changes over time. I have done this work in tidal marshes and lakes and in tropical forests, where the focus is on the hyperdiverse communities of tree seedlings that represent the future of the forest. Most recently, I have been studying alpine and subalpine plant communities of the Northeast, where we are looking for evidence of changes in species composition that might be related to warming, nitrogen deposition or changes in precipitation.
I recently retired after 10 years as the plant collections manager in the G.S. Torrey Herbarium, but I remain active as a researcher in the Department of Ecology and Evolutionary Biology. In fact, I have moved to Maine, in part to be closer to the mountains where much of my current research is focused.