332 CITRUS FRUITS AND THEIR CULTURE. 



Though in some cases water is obtained from wells, 

 most of it is procured from reservoirs in the mountains 

 or from rivers, being conducted to the fruit districts in 

 pipe lines or canals. From these each individual grower 

 receives his supply. 



DISTRIBUTION OF WATER. 



The water is usually delivered in ditches, cement 

 flumes, wooden flumes or cement tile lines at the highest 

 part of the grove and from there distributed to the 

 trees. The methods of irrigation commonly used are 

 the furrow and check, the former being the one most 

 generally adopted. 



FURROW SYSTEM. 



In the furrow system the water is delivered in a 

 flume along the higher portion of the grove and the water 

 is delivered through the gates into the furrows which 

 run out between the tree rows. The number of furrows 

 to each interspace varies with the size of the trees as 

 well as their age. In irrigating small trees fewer fur- 

 rows are used, while in groves of large trees set twenty 

 to thirty feet apart from five to nine furrows are used. 

 The water is not turned into all the furrows of the grove 

 at once, but is supplied to a small number at one time. 

 Through these furrows the water makes its way, until 

 it reaches the lower end when the gates in the flume are 

 closed and the water diverted into another set of furrows. 



The continued application of water at the same depth 

 frequently brings about the formation of what has been 

 termed "irrigation hardpan." The soil on a level with the 

 bottom furrows becomes hard and compact and prevents 



