EVALUATING WATER-SUPPLY OUTLOOK FOR FERTILIZING HAY UNDER VARIABLE STREAMFLOWS

This study examines the value of annual streamflow forecasts (issued cooperatively by the Soil Conservation Service and National Weather Service) for adapting fertilizer use to expected streamflow when producing mountain meadow hay in the upper Wind River area of Wyoming. Streamflow forecasts are found to be 90% effective for predicting above or below average streamflow over the 6-mo (April-September) period from February forecasts. Applying N fertilizer in response to forecasted water supplies in an example mountain hay meadow yields additional net revenue of at least $7.94/acre compared to fixed, nonadaptive strategies of regularly fertilizing either all, 50% or none of the affected meadow acreage. In addition, streamflow forecasts appear to provide risk-averse producers a viable basis for increasing hay production with N fertilizer, given conditions of variable water supplies.