Cultured longstanding hayfields and pasture being made on theplough-lands production increase and stabilization

The man-made factors complex is defining nitrogen chemical fertilizers influence on the biological nitrogen fixation. Common tendency of the negative influence of the nitrogen fertilizers increase on the legumes is shown. It is defined, first of all, by the competitiveness amplification for the water, light and nutrition elements. Also it is defied by the activity change of the pit microflora. Application of the nitrogen fertilizers at the Non-chernozem area in the clover-timothy mixture is always more effective, than in the meadow-clover. Using such a method as sod volume tallage against a background of the prior lime and fortified with the trace elements phosphoric-potassium fertilizer application at the unhomogeneous herbage increases the legumes content.