SMALL FURROW IRRIGATION \jg 



ing water from these ditches to cover the lower sections. I formerly used 

 pipes to lead the water down the steepest grades, but this system I have 

 abandoned and now use open zigzag ditches for mains. From the main 

 zigzag ditches I do not take the water at the turning point, as there is more 

 liability of breakage than if taken when running straight, or at whatever 

 point is necessary to keep the distributing ditches on an average of 8 feet 

 apart. The length of the zigzag ditches varies according to the slope of the 

 hillside. When steep, the ditch, before turning, must be of greater length 

 than where the ground is more level. (See diagram.) I use no gates, but 

 bush the openings with coarse swale hay. I also bush the turning points of 

 ditches as they are in permanent use throughout the season, and after the 

 first few days' use require but little care to keep them in order. These 

 ditches are torn up during the season of cultivation and have to be renewed 

 every year. 



I use a level set on a frame 8.25 feet long and about 2.5 feet high (one 

 leg longer than the other) to make any grade desired. Then I drag its 

 length on the ground after getting the level, and can mark the line of ditch 

 nearly half as fast as a man can walk. 



I have used many thousand feet of pipe in irrigating, but found it too 

 expensive to be practicable, and it frequently gets clogged, causing much 

 trouble. The zigzag method of taking the water down hills on the dry 

 ridges, distributing to right and left, picking it up again in zigzag ditches 

 at the end of the rows or system, to be used again on lower ground, brings 

 into use the largest quantity where it is most needed and utilizes it all with- 

 out waste. 



Irrigating by Small Furrows. It has already been suggested 

 that recently the small furrow method of irrigation is undergoing 

 certain modifications. The occasion for the change is that in certain 

 of the heavier soils, particularly, the use of water in many shallow 

 furrows followed by cultivation results in the formation of a compact 

 layer, and this prevents the percolation of the water into the subsoil. 

 This discovery led many Southern growers to resort to fewer and 

 deeper furrows, and to new devices to enable the tree to get the 

 benefit of the water. There has been wide use of the subsoil plow, 

 with a wedge-shaped foot attached to a slim standard rising to the 

 ordinary beam. The standard opposes its thin edge to the soil so as 

 to cleave it with the least difficulty, and the foot, passing through 

 or beneath the hardpan, lifts and breaks it. The result of the sub- 

 soiling is to open a way for the water to sink and spread below the 

 hardpan. It is usual to run this plow once through the center of the 

 interspace between the rows of trees, sometimes at right angles to 

 the irrigation furrows. When this is done the water is admitted to 

 the furrows as usual, but instead of flowing along smoothly it drops 

 into the track of the subsoiler and runs there a long time before 

 rising again to continue its course down the furrow. It is the ex- 

 perience of some growers that the water has taken five or six days 

 to reach the lower end of the furrows, a distance which would have 

 been covered in twenty-four hours if the subsoiler had not inter- 

 vened. This has been shown to result in much water for the subsoil 

 and a notable invigoration of trees which had been famishing, 

 although shallow-furrow irrigation had proceeded regularly. 



Changes in the furrow method at Riverside, California, are de- 

 scribed by Mr. J. H. Reed as follows : 



The handling of the water in the orchard has materially changed in recent 

 years. Instead of flooding up, basining, or using shallow furrows, deep 



