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Show NEl., u- more water Many Conditions Play Important Part in Amount Required. Rotation Is Found to Ge Beneficial as Well as in Some Cases Absolutely Absolute-ly Necessary to Produce Irrigated Crop. (By RALPH E. PARSHALL, Colorado Agricultural College.) Not only methods of irrigation subsoil sub-soil conditions and climatic conditions affect the duty of water, but the kind of crop, the preparation of the fields for irrigation, as well as many other conditions, play an important part in the correct amount of water that should be used to mature a certain kind of crop. Ideal conditions are never possible, so we must make the existing conditions condi-tions approximate, as well as we can, that which Is best for the conservation of moisture. Each, ysr in cur Irrigation history we are finding the need of more water to cover the areas prepared for cultivation culti-vation In our western Country. We are, In a way, successfully meeting this Issue, but we still see before us many things desirable in ways of methods and Improved conditions that will greatly increase the area now being Irrigated with a certain water Bupply. The community that specializes In a particular kind of crop that requires Irrigation at particular times, necessarily neces-sarily cannot obtain the highest duty of water, because at , the intervals when the crop Is not In need of water this Irrigation head could be applied to other fields where profits could be substantially increased. A diversification diversifi-cation of crops is recommended where the farm Is Irrigated by ditches that flow continuously. Where water Is scarce und many farms are to be irrigated b ' a certain water supply, we find it tceedingly wasteful to attempt the lr: gation of the whole area at the same ime. Rotation Ro-tation in the use of water 1; found to be beneficial as well as In s" ne cases absolutely necessary to p duce a crop. By the rotation In t 3 use of water a larger irrigation hi id is assured as-sured and the losses from e lporatlon and percolation are materially decreased, de-creased, leaving more water available for the beneficial use of the plants. Where small heads are used In irrigation irri-gation we find the area we can cover smaller as compared with the larger head, and we further find thai In our attempt to cover the area with the smaller head of water we are obliged to have the water set at a particular place long enough to cover the area In question that we find a great amount of the water has percolated far below the root zone of the growing grow-ing plants and is absolutely lost. We can .cover a larger head of water and the losses in the latter case are considerably con-siderably smaller than In the former. The preparation of the fields for irrigation will Increase the duty of water In that It makes It possible to thoroughly Irrigate the field in a much shorter time, and again our losses due to percojation and evaporation are lessened. les-sened. Perhaps the greatest factor affecting affect-ing the duty of water Is that of cultivation. culti-vation. If the water absorbed by the soil can only be retained and made available of the growth of the : plant, the problem of the duty of water has been practically selved. Crops that will permit a thorough cultivation after ft thorough application of water will snow a decided increase In the yield. It has been determined that the evaporation from an uncultivated field In a single month is four times that of a similar field having a three-Inch three-Inch dry mulch. |