296 IRRIGATION PRACTICE 



or four lighter irrigations, or six light irrigations. Within 

 existing practice, sugar beets receive from 15 to 24 inches 

 of water, according to the prevailing water conditions, 

 except in the newer districts where water is abundant, 

 when even more is used. The development of more rational 

 methods will reduce the quantity now used. 



The irrigation season for sugar beets seldom exceeds 

 ninety days. If a depth of 15 niches of water is applied 

 during this season, a second-foot of water will have a 

 duty of 144 acres; if 18 inches are applied, a duty of 120 

 acres, and if 24 inches are applied, a duty of 90 acres. 

 The present practice makes the duty of water for sugar 

 beets about 150 acres, with a rapid upward tendency. 



As explained in Chapter XI, the percentages of sucrose 

 and purity are highest when medium quantities of water 

 are used in sugar beet production. The quality of sugar 

 beets is especially improved when water is withheld 

 several weeks before harvest. The ripening and increase 

 in sugar and purity go on until very late in the fall. Water 

 is often applied late, in the hope that the yield may be 

 increased. This seldom occurs, and when an increased 

 yield is obtained, it seldom pays for the labor of irriga- 

 tion; moreover, it causes a decided loss to the sugar fac- 

 tory, which depends upon the sugar content for its profit- 

 able operation. Sugar beets bought on the basis of sugar 

 are not subjected to late irrigations. 



The shape of the sugar beet is materially improved 

 when moderate quantities of water are used. An early 

 irrigation produces turnip-shaped beets, and late or heavy 

 irrigations produce forked or irregular beets. 



178. Carrots. Carrots are grown practically as are 

 sugar beets, though less attention is given to quality and 

 more to the total acre yield. Irrigation studies of this 



