292 IRRIGATION PRACTICE 



but, if the beets are wilted in the morning, it is a fairly 

 sure sign that irrigation is necessary. 



On the deep, fertile soils of the West two to four irri- 

 gations should be sufficient for the season. On porous, 

 gravelly soils, more water will be necessary. Many of the 

 sugar factories advise two irrigations; few advise more 

 than three. In liberal practice, three to five irrigations 

 should be ample. The final irrigation should occur at 

 least four to six weeks before harvest; that is, from Sep- 

 tember 1 to September 15, so that the beets may have 

 ample time to ripen in the cool weather of fall, and be 

 ready for the factory. Water applied late causes late 

 growth, with a decided fall in the sugar content, and often 

 in the yield. The great length of the growing season makes 

 it probably better to apply a small total quantity of water 

 in several irrigations than in one. Many irrigations tend 

 to give an increase in the yield; but more than four or 

 five seldom pay in added yield for the increased cost of 

 irrigation. Where the annual rainfall is from 12 to 15 

 inches, most of which falls in winter and early spring, 

 there is little or no need of irrigation in June. In July, when 

 the growth is rapid, two irrigations; in August, not more 

 than two, and in September, at the most one irrigation 

 should be applied. The Utah work indicates that, of the 

 total quantity of water to be applied throughout a sea- 

 son, about 45 per cent should be added in July; 35 per 

 cent in August, and about 20 per cent in June and Sep- 

 tember. A small total quantity during the season elimi- 

 nates irrigations in June and September. Clay loams 

 should not be irrigated oftener than every two weeks. The 

 number of irrigations in a season depends, after all, upon 

 the total quantity to be used. With a heavy annual rain- 

 fall, little irrigation, therefore few applications; with light 



