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1 area basis. With experience, the error in estimating seasonal' water 2 use can be small, but short-term errors are appreciable. To compen- 3 sate for these short-term fluctuations in demand and to make maximum 4 .use of rainfall, the storage capacity of the soil profile needs to be. " 5 used effectively. In rainfed agriculture, water stor~d in the soil 6 profile is often the only source for a growing crop. The quantity of 7 water that can be withdrawn from storage, in such cases, is often not 8 limited as much by the quantity stored as it is by the rate it can be 9 withdrawn by the growing crop. Once this rate drops below the crop's 10 needs, for reasons explained above, growth begins to decline, and in 11 severe cases, the crop dies. Often this occurs with considerable stored 12 water left in the soil profile. But, it is at depths too great. to be 13 moved to the crop's root su~faces fast enough to sustain life. By sup~. 14 plying part of the crop's water needs with frequent, light irrigations, 15 the remainder can be withdrawn from deep storage at a sustained, but 16 much slowe.r, rate. without reducing crop growth. Fischbach et a1. (5) 17 have used this method of gradually depleting stored soil water during 18 the growing season to make 'soil storage' capaci ty available for winter 19 rains, and to reduce the maximum required capacity of a center pivot J sprinkler system. High-frequency irrigathon goes a long way toward 20 211 ~eeting the conflicting demands of maintaining the soil wet enough for 22 maximum yield while providing sufficient capacity to store erratic 23 rainfall, or short-term mismatches between the quantity of water applied 24 as irrigation and that required by the crop. 25 (' r,(",oO Yet another advantage of irrigation systems capable '6f' 'iii~terlng 26 water precisely, uniformly, and frequently to the individual plants re- 27 gardless of topography or soil properties de.ser'j~~-s attention. S'J:-!..uble