Irrigation

“ The water of irrigation, on the other hand, is applied for many months in succession, it is drawn from rivers and canals at the seasons when the proportion of salts is greatest, and it either sinks into the superficial soil, carrying with it the saline substances it holds in solution, or is evaporated from the surface, leaving them upon it. ”

“ The Process.—Broad irrigation is the discharge of sewage upon the surface of the ground, from which a part of the sewage evaporates and through which the remainder percolates, ultimately to escape in surface drainage channels. Sewage farming is broad irrigation practiced with the object of raising crops. Broad irrigation can be accomplished successfully without the growing of crops, but it is seldom attempted as some return and sometimes even a profit can be obtained from the crops raised. ”

“ If the farmer does not wish to fallow his family garden he can achieve equally good results by planting the rows twice as far apart as is ordinarily the case and by bringing the irrigation furrows near the rows of plants. Then, to make the best use of the water, he must carefully cover the irrigation furrow with dry dirt immediately after the water has been applied and keep the whole surface well stirred so that evaporation will be reduced to a minimum. The beginning of irrigation wisdom is always the storage of the natural precipitation. ”

“ The direct use of the water of irrigation as a solvent for the mineral ingredients of the soil, is one of its main benefits.
To describe the many modes of irrigation would be too long a task for our limited space. It may be applied in any way in which it is possible to cover the land with water, at stated times. Care is necessary, however, that it do not wash more fertilizing matter from the soil than it deposits on it, as would often be the case, if a strong current of water were run over it. Brooks may be dammed up, and thus made to cover a large quantity of land. ”

“ The second method, that of broad irrigation, is one that finds considerable favour with a large number of engineers and agriculturists. The great sewage-disposal cry has always been, “Put back on the land what you have taken from it, or some day there will be no beef and no bread.” The difficulty is to always find land in sufficient quantity and so situated as to be available for this purpose. Almost any soil is, however, suitable for irrigation, provided it is well and properly drained. ”

“ Without irrigation, we have not found the crop very profitable, but there are a few favored spots in the state where it can be grown without water; but when we plant we usually select such land as can be put under a perfect system of irrigation before using. ”

“ It was maintained that mountain irrigation is not ultimately injurious to that of the plains below, because lands liberally watered in the spring, when the supply is abundant, act as reservoirs, storing up by absorption water which afterwards filters down to lower grounds or escapes into the channel of the river and keeps up its current in the dry summer months, so as to compensate for what, during those months, is withdrawn from it for upland irrigation. ”

“ We may irrigate by flooding the land or by leading the water in furrows between the vines. Both ways, but especially the former, may, if continued long enough, cause subirrigation, the most desirable state of irrigation. The choice of methods of irrigating does not always lie with ourselves, but depends upon the quantity of water at our command, the lay of the land, etc. Sometimes one method will in course of time give room to another, and again, after the lapse of a few years, continued irrigation may not be necessary or desirable. ”

“ Irrigation, or watering land, is a practice, he observes, which at first view appears the reverse of torrefaction; and, in general, the operation of water in nature is to bring earthy substances into an extreme state of division. But in the artificial watering of meadows, the beneficial effects may depend upon many different causes, some chemical, some mechanical. It may act as a simple supply of moisture to the roots, or it may carry into the soil foreign matter, or diffuse that which exists in it more equally through its substance. ”

“ Throughout the portions of the country where rains occur during the growing season it should not be necessary to irrigate except occasionally in order to produce the ordinary garden crops. In arid regions, where irrigation must be depended upon for the production of crops, the system best adapted for use in that particular locality should be employed in the garden. Wherever irrigation is practiced the water should not be applied until needed, and then the soil should be thoroughly soaked. ”

“ Water for irrigation is obtained from streams, and it should be applied as quickly as possible, the best way being to flood the whole field for a few days, and then take all the water off, as standing water will kill the plant quicker than anything else. ”

“ Irrigation fills the soil with moisture and drainage empties it. Thus, a condition is established that supplies valuable farm plants with both air and moisture. In the drier portions of the United States, nothing of value will grow without irrigation. In the so-called humid districts deficiency of moisture at the critical time reduces the yield and destroys the profit. The value of irrigation has been demonstrated in the West, and the practice is working eastward. ”

“ Yet since alkali salts are the symptoms and result of insufficient rainfall, irrigation is a necessary condition of agriculture wherever they prevail. Under irrigation, neighboring spots will oftentimes merge together into one large one, and at times the entire area, once highly productive and perhaps covered with valuable plantations of trees or vines, will become incapable of supporting useful growth. ”

“ On very closely planted beds a crop can get in serious trouble without irrigation in a matter of days. But if that same crop were planted less densely, it might grow a few weeks without irrigation. And if that crop were planted even farther apart so that no crop canopy ever developed and a considerable amount of bare, dry earth were showing, this apparent waste of growing space would result in an even slower rate of soil moisture depletion. On deep, open soil the crop might yield a respectable amount without needing any irrigation at all. ”

“ To accomplish a successful work of irrigation attention must not only be turned to the dry and arid land, but to the marshy, low-lying parts that have got more of the water than they need and require draining, otherwise an even flow over the whole can never be engineered and the full capacity of the soil cannot be given a fair chance. ”

“ Irrigation is practiced on every farm. Fifteen thousand acres are covered by water stock, but not all irrigated yet. Just now the orange groves are irrigated, and I observe their methods. The land is always leveled before anything is planted, as there is too little water here to waste any on unlevel land. One way to irrigate an orchard is to plow furrows in between the rows of trees, and then let the water run in them. ”

“ But it seldom happens that pure water is employed for the purposes of irrigation. The water of rivers, more generally, is diverted from its course, more or less loaded with mud and other finer particles of matter, which are either gradually filtered from it as it passes over and through the soil, or in the case of floods subside naturally when the waters come to rest. ”

“ The flow of irrigation water produces the same compacting effect, but to a less extent; the more as, unlike rain water, irrigation water usually contains a certain amount of alkaline and earth salts, which tend to prevent the diffusion of clay and of fine sediments, and therefore the disintegration of the soil-floccules into single grains. Nevertheless, it is in some soils as necessary to cultivate after surface-irrigation as after rains, in order to prevent great waste of moisture by evaporation. ”

“ Irrigation, of course, cannot prevent rainfall, and it may be that after a copious soaking of the ground with the irrigating water a heavy rain may follow, resulting in an excess of moisture as bad for the ground as none at all. The possibility of irrigation cannot prevent excessive rains at the time of harvest, but the advantages of being able to control the soil moisture during the period of growth are more than enough to counterbalance any possible disadvantages. ”

“ Irrigation Interests.—A great industry like that of agriculture demands that in all regions where irrigation is carried on the source of the water supply be protected. The future existence of the farms, and to a large extent of the States themselves, depends upon the conservation of the water supply. The forest areas are largely the reservoirs in which the waters are controlled and given out to the adjacent irrigable districts. ”

“ Where the plan of irrigation includes the storage of the water of the non-growing season, by which all the waters of the year are held under control, the flood-plain lands can be used to advantage, from the fact that they lie in such a way as to be easily irrigated and their soils possess elements and conditions of great fertility. ”

“ The first rays that fall from the lamp of history reveal vast systems of irrigation in full operation. In many parts of the globe artificial watering is absolutely essential, and there are few agricultural regions which might not be rendered far more productive if the supply of moisture could be regulated in accordance with the needs of each crop. The question, as we shall consider it, is a practical one. In California and other sections, the land must be irrigated ”

“ On a fine retentive loam, the crop is chiefly made without irrigation, if the plants are all ready to put out in the field as soon as it is safe. If you are late in the planting, or if the soil is dry or likely to dry before the tubers are grown to good size, irrigation, some time ahead of the need of the plant, is essential. ”

“ But if such a change is ever brought about, the irrigator will be the principal cause of the transfer of leadership from the man of the corn lands to the man of the fruit lands.
Twenty years ago no one in America knew how to utilize water on a large scale for irrigation. A few colonies in different parts of the arid zone, a few settlers in isolated valleys, were making experiments. Half a dozen ranchers would come together and plow an open ditch two or three feet wide, to irrigate their crops in years of severe drought. ”

“ Irrigating By irrigation is meant the purposeful distribution of water over soil by man by means of diverting streams or by the use of canals in the shape of ditches or troughs for conveying and directing part of a water supply, or by means of some other man-directed power to raise water to the required level. ”

“ One wonders whether, if more of us were pushed to it, we might not find irrigation so profitable that we would never again be without it. Cultural and soil corrective practices are, in general, similar to those previously reported. ”

“ Plentiful irrigation, however, is relied upon to counteract that fatal pest of the vine, the phylloxera. Some advocate the theory of irrigation in the winter or rainy season only. All the water possible is to be conducted upon the land at the time it naturally falls, leaving the soil to act as its own reservoir, and store up a portion for the dry season ahead. Others even deny the need of irrigation altogether. ”

“ We irrigate chiefly in the colder and wetter half of the year, and we “saturate” with water the soil in which are growing such plants as are perfectly content with earth not containing more than one-fifth of its weight of moisture. We must look in fact to a number of small advantages and not to any one striking beneficial process in explaining the aggregate utility of water-meadow irrigation. ”

“ In other words, the water stored in the soil by the natural precipitation and the water that falls during the spring and summer can either mature a small crop or bring a crop near maturity. A small amount of water added in the form of irrigation water at the right time will usually complete the work and produce a well-matured crop of large yield. Irrigation should only be supplemented to the natural precipitation. As more irrigation water is added, the increase in yield becomes smaller in proportion to the amount of water employed. ”

“ Much of the surface, though not out of the reach of irrigation, lies too high to be economically watered, and irrigation and cultivation are therefore at present confined to an area of seven thousand square miles, nearly the whole of which is regularly and constantly watered when not covered by the inundation, except in the short interval between the harvest and the rise of the waters. ”

“ If but 3000 gallons hourly trickle over and through an acre, and if we assume each gallon to contain no more than one-tenth of a grain of plant food of the three sorts just named taken together, still the total, during a season including ninety days of actual irrigation, will not be less than 9 ℔ per acre. It appears, however, that a very large share of the benefits of water-irrigation is attributable to the mere contact of abundance of moving water, of an even temperature, with the roots of the grass. The growth is less checked by early frosts ”

“ In dry and arid climates, where rain rarely falls, the soil may contain all the elements of fertility, and require only water to call them into operation. In such cases, as in the irrigations practised so extensively in eastern countries, and without which, whole provinces in Africa and Southern America would lie waste, it is unnecessary to suppose any other virtue in irrigation than the mere supply of water it affords to the parched and cracking soil. ”