Peanut irrigation management using climate-based information

Irrigation is important in maintaining peanut yield and quality in the Southeastern US. Demand for irrigation in this region is expected to increase in the future. Compounding the problem of increased water demand is the fact that crop yields are impacted by climate variability, especially El Niño-Southern Oscillation (ENSO) events. For farmers facing limited water supply, deciding on the amount of irrigation or which area of their farm to take out of production can be a daunting task. There is a need to combine climate information and risk analysis, and to provide growers with tools and information to assist them in managing their risks. An irrigation decision tool for peanut production was developed to provide probability distributions of the seasonal cost to irrigate peanuts under different climate forecasts. Yields were simulated for both irrigated and rainfed peanuts using the CSM-CROPGRO-Peanut model. The tool was used to examine the effects of different planting dates, soil types and climate forecasts. Results of a case study are presented for the Georgia Green variety grown in Miller County, Georgia. The probability of obtaining a high net return under irrigated conditions increased when planting dates were delayed for El Niño years. Dryland peanut production was profitable in a La Niña year if peanuts were planted between mid-April and early May. The peanut irrigation decision support tool will be deployed as a web-based tool on the AgClimate web site (www.agclimate.org).