ARID AGRICULTURE. 97 



is to plow and harrow over them, remaking them 

 each year. This is more convenient, as the drills 

 and other farm implements can then be driven 

 across the field without interference- hy the 

 ditches. It entails the extra work of listing 

 out and trimming the ditches each year. Per- 

 manent ditehes should also be repaired and 

 trimmed each year, for if this is not done, they 

 are very apt to become irregular, cut out in 

 places, and stopped up with vegetation in other 

 places. The common lister and the V-shaped 

 crowder or "Go-Devil," are the implements 

 commonly used in making field ditches. The 

 "A,' 7 or "Go-Devil," is easy to construct, and 

 can be adjusted to make various widths of 

 ditches. In preparing ground for this kind of 

 irrigation it should be brought to a uniform 

 slope by means of scrapers and home-made lev- 

 olers, or some other levelling device, as the labor 

 of irrigating each year will depend on how well 

 this has been done. This method is in general 

 suitable for medium slopes, soils which do not 

 bake or crust badly after flooding, grains, mead- 

 ows and hay crops, and for the extensive system 

 of farming, where lands are not of great value, 

 and such crops as require comparatively little 

 attention are raised. While in first outlay the 

 expense necessary is not large, the annual cost 

 for irrigation is usually excessive. From two 

 to five acres a day is as much as one experienced 



