438 



IRRIGATION PRACTICE 



FIG. 160. Cutaway disk harrow. 



canvas dam is made of a piece of strong canvas, nailed 

 firmly to a wooden cross piece. At times there is an open- 

 ing in it to divide the irrigation stream. Sometimes a 

 small obstruction such as a submerged flashboard or a 

 lath dropped across the bottom of the ditch is sufficient 

 to divert the water into the lateral. (Figs. 141-150.) 



FIG. 161. Clod crusher, pulverizer, leveler and smoother. 



