Dry Farming and Irrigation 167 



planted, the whole field is laid off like a checkerboard 

 in areas small enough so that each one can be graded Grading 

 perfectly level. Each level area or " check " is sur- 

 rounded with ridges of dirt, so that water several inches 

 deep can stand on the check until it soaks into the soil. 

 One or more of the checks may be flooded at a time, Applying 

 depending on the amount of water available. Some- e water 

 times the checks consist of strips fifty or a hundred 

 feet wide and perhaps a quarter of a mile long, made 

 level from side to side, but sloping from end to end. 

 Water is flooded in at the upper end of the strip, and 

 the gentle slope carries it through to the other end, 

 thoroughly soaking the whole area. The check system 

 is often used for alfalfa fields. The water destroys 



W. T. SkUling 



FIG. 131. A miner's inch flowing. The water level is kept 4 inches above 



the hole. 



