Los objetivos propueatos fueron: determinar la influencia de los tratamientos sobre la producción del forraje, el grado de adaptibilidad de tres variedades de a faifa y su economía. Se utilizó un diseño estadístico de bloques completos al azar, en un rreolo factorial de 3 x 3 x 2, con cuatro repeticiones, para compara ración de medias, so utilizó Duncan, para nitrogeno, Polinomios ortog; nales y para Rhizobium , D.M.S.The present work in the farm "IMERHI" in Salinas de Ibarra, at 1.500-o 1.850 meters of altitude, with an average temperature of 19 - 20 C, with a 500 - 600 mm. of rainfall, and a soil pH« of 8,5, The proposed objectives were: determine the influence of treatments on forraje pro^ duction and quality, the adaptability of varietes of alfalfa, and its economics. The experimental desing used was completely randomized blocks, in a fetorial arrangement of 3 x 3 x 2 with four repeticions. The comparisions of means was realized using, D u n c a n’s multiple - range test, orthogonal Polinomials were used to compare levels of nitrogen, and Significant Difference was used to test the effect of Rhizobium.