Year Established: 2015 Start Date: 2015-03-01 End Date: 2016-02-29
Total Federal Funds: $25,000 Total Non-Federal Funds: $50,000
Principal Investigators: Jason Warren, Jody Campiche, Rodney Jones, Arthur Stoecker
Abstract: During the 2013 and 2014 crop years efforts have been made to compare yield potential for sorghum and corn when irrigated at a range of irrigation capacities that represent the pumping capacities found in the Oklahoma Panhandle. This effort has been made to determine the irrigation capacity at which sorghum becomes more productive and profitable than corn. We are currently utilizing this data to calibrate the EPIC crop model to allow us to simulate long term average yields as well as variability in yields for these crops. This will allow for determination of profitability and risk. While our current efforts will be fruitful in allowing us to understand the value of water when used to produce corn vs sorghum it does fall short from providing a complete assessment of possible crop production options. Specifically, irrigation wheat production must also be included in our analysis because of its prevalence in the area. In fact, the National Agriculture Statistics Service reports that in 2012 there were approximately 80,000, 13,000, and 45,000 acres of corn, sorghum and wheat respectively. The decision to grow wheat under irrigation is generally based on the need to rotation out of corn to control pest pressures and therefor our current efforts have focused on comparing corn and sorghum in order to assist producers in deciding which is more economically advantageous. However, we must include wheat in our analysis to insure a holistic understanding of the irrigated production system. The Objectives are to evaluate the yield and water use efficiency of corn, sorghum and corn under a range of irrigation capacities. The second objective is to evaluate the profitability and production risks of these crops such that producers can make sound decisions on the utilization of their water resources. This research will utilize the subsurface drip irrigation system located at the OSU Panhandle Research and Extension center. This allows for a randomized split plot treatment structure with whole plots being crop (sorghum or corn) and irrigation application rates serving as subplots. The irrigation rates will simulate irrigation systems with pumping rates ranging from 100 to 800 gallons per minute applied to 125 acre. These would be equivalent to 0.04 to 0.33 inches of water per day, respectively. The sorghum, corn and wheat crops are expected to be irrigated with approximately 3-20, 8.5-30, and 3-15 inches, respectively. Grain sorghum treatments will be planted in early-June, 2015, corn treatments will be planted in mid-April, 2015 and wheat will be planted in mid-Oct, 2014. Soil profile moisture status will be evaluated prior to planting by collection of soil cores from each plot to a depth of 8 ft and cut into 1 ft sections. Bulk density and soil moisture content will be determined such that volumetric water content can be determined. Soil samples will be collected from each plot after harvest to evaluate soil moisture status. Yield and water balance data will be used in combination with historic weather data to conduct probability analysis to evaluate the variability in water requirements for each crop as well as the risk of crop failure under limited water supply. This will be combined with economic analysis to evaluate how profitability of these crops changes with declining water availability.