Effect of ENSO Phase on Seasonal Forage Yield of Annual Ryegrass.

The effect of El Niño Southern Oscillation (ENSO) phases (El Niño, La Niña, Neutral) on yield has been demonstrated in many crop species. We examined total seasonal forage yield of annual ryegrass (Lolium multiflorum Lam.) from five states (AL, GA, LA, TN, TX) and multiple locations within each state. The largest year-to-year variation was observed among years in the neutral phase, followed by La Niña. There was little variation among years with the El Niño, which tend to have much cooler winters and springs than the other phases. Other observations of interest are that no matter the phase, year-to-year was smaller at the extreme northern and southern edges of the geographic range examined. Knowing the ENSO for the upcoming season has profound implications for forage inventory management.