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Field inoculation studies were carried out on loamy clay, brown steppe soil to test the potential and yield of berseem clover (Trifolium alexandrinum) planted separately and together with ryegrass at 50:50 ratio. The experimental site was located on the border of the desert zone of Israel, with an annual average rainfall of about 350 mm. Four cuttings were carried out during the growth period: 88, 121, 158, and 183 days after planting. Clover dry matter and N uptake obtained at the first cutting from the plots inoculated by an effective Rhizobium trifolii strain out-yielded those in the uninoculated plots by 39 and 36%, respectively. In four cuts inoculated clover:ryegrass mixture produced 11 880 kg ha-1 dry matter containing 2349 kg of crude protein, which was 11 % more than inoculated clover grown alone. These figures were not significantly different from the yields of ryegrass fertilized with 500 kg N ha-1. The N2 fixation rates of clover plants grown in mixture with ryegrass were higher than in those planted as a monoculture. These results suggest that the depleted pool of soil nitrogen in intercrops enhanced the symbiotic N2 fixation of clover