FIVE YEARS OF SOIL ANALYSES AND YIELD DATA ON DEEP-PLOWED SOLONETZIC SOIL

Abstract

Crop yields and soil data were obtained for 5 yr on 12, 1-ha plots of slight to moderately saline Solonetzic soil which had been plowed to a depth of 61 cm. Wheat, durum wheat, oats and flax were grown. Wheat yields range from a decrease of 0.25 t/ha to an increase of 0.74 t/ha. An average increase of 0.34–0.40 t/ha should be expected from deep plowing this type of soil. The surface soil following deep plowing increased in clay, fine clay, pH, CaCO3 and H2O-soluble Ca. It decreased in H2O-soluble Na. Water-soluble Mg remained relatively constant. With moderate fluctuations, these changes have persisted for 5 yr. Key words: Deep plowing, Solonetzic, sodium, calcium carbonate