Start Date: Feb 14, 2007
End Date: Feb 13, 2012
We will use small plot field trials to develop water production functions, weed management strategies, and remotely sensed water deficit measurements of four crops (corn, sunflower, wheat and dry beans) under two tillage systems (conventional tillage and minimum tillage). The effects of tillage and limited irrigation on crop yields, weed population dynamics, and herbicide efficacy will be measured. Deficit irrigations will be scheduled to optimize production using past studies of critical growth stages and crop simulation models. Active and passive sensors on ground-based platforms will measure crop response to water and nitrogen stress. The research will be done in collaboration with an agriculture economist and crop modelers to provide basic information for both short and long-term decisions on the best way to maximize economic return with limited irrigation water. Field measurements and computer simulation studies will be used to determine the utility of site specific weed management in growers' fields. We will contribute to an ARS effort to develop a model for NRCS to assess the impacts of cropping systems and irrigation practices on furrow irrigation-induced erosion.