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Show SUIT SOIL CONDITIONS Irrigation Becomes More Expensive Expen-sive Year by Year. Most Economical Distribution of Water Will Depend on Running It Proper Distance Careful Preparation Is Necessary. Water becomes more expensive year by year and much more money is now spent to make irrigation in the field effective than formerly. Given skilled help and big heads of water our common com-mon system of laterals 35 or 40 yards apart is a good one, and the amount of water that can be handled by a good man by using several ditches is only limited by the size of the head ditch, though the ordinary hand will have enough to do to run two or three ditches full. There are now much better bet-ter ditch plows than formerly, which leave a better ditch bank to keep the water from breaking back into the laterals lat-erals from which, it has been forced, and good banks are the measure of a good ditch flow, which must he suited to the land, laying the banks farther back in friable soils than on stiff loams or clays, or they will cave in when the water strikes them. The heels of the lays should have three to five inches cut off them or they will cut in under the bank and the water will find the crack and undermine under-mine the embankment, which will flat- ten out. With really good banks to our ditches the upper parts of the land we have laid off are watered in practically prac-tically the same way as by the check system, where we merely depend on the head ditch to carry water and larger or smaller embankments are put through the field, leaving le.vel spaces between. ' The distance water should be run from the head ditch without running a supply down the laterals will depend on how easily it is controlled and how much it soaks into the ground in its passage down the field. On some impervious im-pervious soil it is better to run it the whole way if we have a fair head and the lands do not exceed a quarter of a mile. This is exceptional, however, and would only apply to old alfalfa fields or meadows which have become very hard from lack of cultivation. The irrigator ir-rigator with his shovel can tell when land has taken water enough, and should never be deceived in this respect re-spect w:ith ordinary crops, though of very deep rooted ones, like alfalfa. roots reach down beyond our ken; Some soils will absorb water so easily that it must be assisted over the surface by the use of the corruga-tor corruga-tor and frequent changes in the laterals, lat-erals, whilst on others it merely fills the plowed soil and passes on easily over the surface. A good loam will stand up much better than a clay in which the particles are so fine that when thoroughly wetted they become soapy, settling as they dry into a hard, compact mass, which it is very hard for air to re-enter. Clay soils, however, how-ever, will grow good crops if they are carefully watered and conditions are such that the crop conies away fast, shading the ground so it will not scald or crack. Where checks are made, their size should be governed . by the above conditions, .s well as the ability of the water supply to flood a given area without waste of water, and the levels of the land, which, of course, necessitate small areas, or the checks will have to be made inconveniently incon-veniently high. The area to be flooded may run from a few feet of lawn up to thirty acres, a very usual size being from three-fourths to one and one-half acres. The economy of the check will depend on how closely its size is adapted to the most economical distribution dis-tribution of water and the amount necessary nec-essary for the plants. |