THE ART OF IRRIGATION. 



181 



overcome these things generally by forcing a larger 

 head through at the start. Once through, cut it down 

 to just enough to insure continuing through. But 

 don't turn on enough to cut or puddle the furrow to 

 any extent. 



TRY A LARGER STREAM, 



Turn on, therefore, two gallons a minute and time 

 that. If it don't get around clods, leaves and little 

 ridges of dirt at the rate of a yard a minute, increase 

 it until it does. If a stream of two or three gallons a 

 minute does not travel at this speed the furrows are 

 badly made and it will pay you to take more care 

 with them. Remember, if you can make this sys- 

 tem work it will save you time and money, shoe 

 leather and patience incalculable, besides doing far 

 more effective work on nine-tenths of the stuff you 

 will grow. It will also do it with less water and less 

 waste of fertilizers by leaching than flooding. If 

 there is any danger of malaria from irrigation there 

 will be none from this, and in all respects it comes 

 nearer in its results to rain than any other way of ap- 

 plying water that is practicable on a large scale. It 

 was first reduced to its present fine proportions at 

 Riverside, California, and has since spread over all 

 "parts of Southern California, where the soil will per- 

 mit its use and where large enough heads of water 

 can be had for a sufficiently long time. It is not an 

 invention of any one, but is simply an evolution from 

 the common furrow system. In exact proportion to 

 the perfection it has reached has the character of the 

 fruit advanced, until there is no finer in the world of 

 any kind than that produced by the right amount of 

 water applied in this way and the right amount of 

 cultivator afterward. 



TEST THE SOIL. 



In whatever way you wish to irrigate it is import- 

 ant to test the tightness of the soil at the outset. If 

 you have not water enough to use the small furrow 

 method and have to use basins, then it is very import- 

 ant to be able to run the water from basin 

 to basin without losing much of it on the way. 

 When you use basins at all it is because there is 

 no water to lose. To run the water from basin to ba- 

 sin is much less trouble than using hose or water- 

 carts, or any other annoying ways of delivery. You 

 can also vary the shape of your basins more and do 

 better work, even of the basin kind. If you have your 

 water in large heads with a short run, as is sometimes 

 the case, and you are driven to flooding, then, if the 

 soil is tight enough to hold up these small streams, 

 you can flood with less work than where the soil is 

 very loose. There is less danger of the checks break- 

 ing or cutting under a slight leak, and as the water 

 will stand longer in them it will not take the same 

 care to rush it over the field so as to insure a uni- 

 form depth of water in all the checks. 



In making this test, do not be alarmed if the small 

 stream vanishes in a gopher hole every time your 

 back is turned. Where ground had never before 

 been irrigated it is apt to be a perfect sieve from 

 gophers, moles, mice and other burrowing animals. 

 Stop any such hole by pressing dirt into it and let the 

 water go ahead. 



If the stream starts off at the rate of a yard a min- 

 ute for one-ninth of an inch, or a gallon a minute, 

 your soil is all right. But you cannot expect it to 

 hold this speed very long. If the soil is porous 

 enough to be valuable, the stream is losing some all 

 the time and cannot run so fast. The streams in 

 common use where this method is brought to its 

 highest perfection cannot be easily measured be- 

 cause they vary so much. But they range from one- 

 fourth to one-tenth of an inch each, with an average 

 probably of one-sixth. This is guess-work largely, 

 but I have watched them hundreds of times, have di- 

 vided the head by the number of streams, the head 

 being known because paid for at the office, and have 

 asked the opinion of scores of irrigators who were in 

 the habit of dividing up the heads, and one-sixth of 

 an inch is about the average for the finest work. It 

 is, however, common to start with larger streams to 

 rush the water through and then cut them down. 

 Sometimes this cutting reduces them as low as one- 

 tenth of an inch each. But about one-sixth, or a 

 little less, will generally do. 



HAVE FAITH IN IT. 



It takes these streams as ordinarly used from 

 twelve to twenty-four hours to cross a square ten-acre 

 tract. As it is six hundred and sixty feet across a 

 square ten acres, this is a speed of from about six 

 inches to a foot a minute. And this is about what 

 they will make, varying some with the slope of 

 the ground, the care with which the furrows are 

 made, the number of clods that fall into them, etc. 

 The main thing is to let them alone. Go to bed or 

 down town and don't worry about them. At first the 

 holes in the ground will make you plenty of trouble, 

 and unless you have plenty of faith you may despair 

 of making this system work. But after a few irriga- 

 tions, gophers and all other things that make holes 

 will disappear and no more will come. The holes 

 will fill up and the water will run evenly in every 

 furrow that is properly made. 



If the water runs at the rate of a yard a minute at 

 the start, the soil is right for any method of applying 

 water. But if does not run at that speed it by no 

 means follows that you cannot use small streams. 

 The top soil may be more porous in one part of the 

 tract than in another. It will be very hard to find 

 a tract of any size with the soil all of uniform text- 

 ure. I have seen it on prairie in wet countries, 

 but there is very little of it in the dry coun- 



