52 GENERAL CONSIDERATIONS 



to run first in one place and then in another until 

 the entire field has been covered. A modification of 

 this method consists in the throwing up of borders 

 or ridges with the plow at right angles to the course 

 of the ditch at intervals of three or four rods. 

 These borders are smoothed up and pressed into 

 shape with a V-shaped plank drag. The ground be- 

 tween the borders is dragged down level, and in 

 irrigating the water is turned into one or two of 

 these S23aces and is allowed to run till it reaches the 

 low^er side of the field, when it is cut off and turned 

 into the next spaces. This is a very practical 

 method of irrigation and it is much used for quite a 

 variety of crops. The distance to which the water 

 can be run across such a field will depend on the 

 nature of the soil and the amount of fall. With 

 everything favorable a square forty-acre field can be 

 irrigated from one head ditch, but in the majority 

 of cases it is better to have ditches every forty or 

 sometimes as close as every twenty rods. When the 

 attempt is made to carry the water too far, it takes so 

 long as to waste the time of the irrigator, and the land 

 at the upper end next the ditch will be under water 

 so long as to injure the crop. 



In orchards and gardens, especially when the water 

 supply is scanty, a system of basin irrigation is often 

 followed. The land is divided into small areas and 

 a border is put up on all sides of each area. The 

 water is turned into the upper area until it has all 

 the borders will hold. After it has stood long 

 enough to soak in to the desired depth the border is 

 cut and the water is allowed to run into the next 



