Forecasting Forage Yield from Precipitation in California's Annual Rangeland

Total forage yield from 1936 to 1970 and yields of grasses, legumes, and forbs other than legumes for 24 years on the same area of annual rangeland on the San Joaquin Experimental Range in central California were correlated with total annual precipitation and precipitation during the most important month, the most important 2 months, and most important 3 months. Total peak forage yield and yield of components of the vegetation were only poorly correlated with any 1 month's, combination of months', or annual rainfall. Early-season precipitation appear to be of little value for predicting forage yield, yield of grasses, legumes, or forbs other than legumes under the conditions studied.