208 



IRRIGATION PRACTICE 



ing by field ditches, this is the most common method of 

 irrigation, and it promises, at least in America, to super- 

 sede all other methods. 

 (Figs. 49, 50.) 



After the crop has 

 been planted, small 

 furrows leading from 

 the supply ditch at 

 the head of the field are made to cover the field by 

 some of the many kinds of markers or furrowers. This 

 process of furrowing the land is known as "marking" or 



FIG. 48. Grading of interior of basins to pre- 

 vent water from coming in contact with 

 trees. 



FIG. 49. Furrow irrigation. 



