Agroecology and Weed Science
- B.A.: Biology (cum laude), Yale University, 1990
- M.A.T.: Biology Education, Brown University, 1993
- M.S.: Ecology and Environmental Science, University of Maine, 1998
- Ph.D.: Crop Physiology and Production (Weed Science), Iowa State University, 2002
- Integrated weed management Most weed management tactics are focused on controlling weed seedlings because they are easy to see, and are quite vulnerable at this life stage. However, a life-history approach to targeting weeds of annual field crops, which tend to be mostly annuals themselves, indicates that weed population growth rate responds most strongly to tactics influencing the weed seedbank. Ideally, integrated weed management strategies should incorporate multiple opportunities for management throughout the weed life cycle. Our research in this area spans investigations of weed seedbank ecology, efficacy of new tactics, and quantifying the impact of multi-tactic integrated weed management systems on the demography of weedy and invasive plant species.
- Spatial ecology of agricultural risk management What are useful spatial scales at which to manage weedy and invasive plant species? What environmental factors and dispersal processes drive the long-term trajectories of plant invasions? How can we make most efficient use of limited budgets for early detection and monitoring to limit the spread of new invaders? These are among the questions that our group attempts to answer in a variety of risk management contexts. Current investigations in this area include quantitative risk analysis of the invasive potential of bioenergy crop species, epidemiology of herbicide resistance evolution in field crop settings, and spatial simulations of the impact of aggregating weed management decisions at spatial scales larger than the individual farm.
- Diversified cropping systems Modern field crop agroecosystems have been greatly simplified to efficiently produce high yields with relatively low amounts of human labor. The enormous productivity of these systems comes with hidden costs in human and environmental health that are often externalized when considering cost-effectiveness of such systems. Our group is interested in testing the hypothesis that high productivity may be compatible with net ecosystem aggradation, yet remain profitable, when cropping systems are diversified to enhance ecosystem service production. Our work in this area includes cropping system design for increased environmental resilience, use of multiple performance indicators to assess agroecosystem sustainability, and pathways to sustainable intensification for small holders in Nepal.