GROWING FIELD CROPS IN SUGAR-BEET DISTRICTS. 



29 



much variation for different farms in cleaning alfalfa ditches, depend- 

 ing upon the type of soil and the slope of the land. Some ditches 

 are inclined to wash clean and deep each year, but others tend to 

 fill up. 



Fig. 20.— Irrigating alfalfa by the flooding method. One man can handle a large head of water. 



At Greeley and at Fort Morgan the first water of the season is run 

 on the alfalfa. The irrigation practice in these districts is very 

 similar, but at Rocky Ford it is somewhat different. Alfalfa is 

 usually irrigated three or four times at Greeley and at Fort Morgan, 

 the first water being applied about May 20, the second about June 

 10, and the third about July 1. Where a fourth irrigation is given 



Fig. 21.— Irrigating com. The furrows are deep and a good head of water is used. Cora is a crop of in- 

 creasing importance in the three districts of Colorado studied. 



it is applied about July 25 or in September. This gives two irrigations 

 before the first crop is cut and one soon after the crop is stacked. 

 The fourth irrigation is just after the second or third crop is cut. 

 The time per acre required for irrigation varies greatly with the 

 flow of water, the type of the land, and the number of applications 



