For the purpose to study the utilization of water, experiments were executed by setting the various weter depth at irrigation and irrigation start, namely 10 cm-10 cm, 15 cm-20 cm, 15 cm-30 cm and 20 cm-30 cm plots using Field Soil of University of Osaka Prefecture. The results obtained were as follow First, the significant difference was recognized between 20 cm-30 cm and 15 cm-30 cm plots and between 10 cm-10 cm and 15 cm-20 cm in respect of total water quantity. And also the significant

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... rence was recognized between 15 cm-20 cm plot and other three plots with respect to available rainfall. Secondly, the significant difference was not recognized with respect to harvest. But the difference was recognizd aboud 10% between 10 cm-10 cm and 20 cm-30 cm plots and between 15 cm-20 cm and 15 cm -30 cm. Thirdly, the mean evapotranspiration on water balance was about 8. 0 mm/day in 10 cm-10 cm, about 8. 3 in 15 cm-20 cm, about 7. 0 in 15 cm-30 cm and about 6. 4 in 20 cm-30 cm. And as water quantity increased, more amount of soil moisture was consumed without connection to harvest of these plots. Last, judging from these experimental results, it was clarified that 20 cm-30 cm plot can save much water quantity, store and utilize much rainfall, and also introduces much harvest and smaller evapotranspiration.