Influence of Folocron Nitrogen Fertilizer Applied in Summer on Alfalfa Yield During Summer Slump

Abstract

Established alfalfa reportedly does not benefit rom applications of N fertilizer since it is a leguminous crop that is capable of fixing its own N from atmospheric N. Some growers feel that nitrogen (N) fixing nodules found on the roots of the alfalfa plant are ineffective during Arizona's hot summers . Thus, N fertilizer is sometimes applied in early summer to established alfalfa to enhance growth and possibly delay or lessen the severity of summer slump to increase alfalfa tonnage. A field experiment was conducted to determine the effect of inorganic and controlled release N fertilizer applied in summer on alfalfa hay yield at the first cutting during summer slump. Three treatments consisted of an unfertilized check plot, broadcast 18-46-0 applied at 27 lbs. N /acre, and Folocron water run at a rate of 30 lbs. N /acre in August to three year old 'CUF 101' alfalfa grown on a silt loam soil. Maximum alfalfa hay yield at the September cutting (0.91 ton/acre) was obtained without N fertilizer application.