IRRIGATION FARMING 239 



190. Sub-Irrigation, or upward irrigation is sometimes 

 used where a very intensive scheme is inaugurated. This 

 is done by the use of tiles laid in the ground just deep 

 enough so that they will not be struck by the plow. 

 These are kept full of water which percolates upwards 

 and sideways from the openings at the ends of the 

 tiles. This is not used on the prairies nor is it apt to be, 

 for, although it has some advantages, the extremely high 

 expense of installation makes it prohibitive. 



191. Relative Suitability of Various Crops under Irri- 

 gation. — -Owing to the fact that our climate is sub-humid 

 or semi-arid rather than arid it is not necessary to irri- 

 gate all kinds of crops every season to obtain profitable 

 returns. In this connection the hay crops are an ex- 

 ception since they rarely if ever produce abundantly in 

 the dry parts without irrigation and they always re- 

 spond favorably to the use of water. There is an old 

 adage that comes from northern Italy where irrigation 

 has been practised for several centuries, which says, 

 "The more water the more hay". This is certainly true 

 in the drier parts of Western Canada with grasses and, 

 with slight modifications, with alfalfa, potatoes and 

 truck crops. Alfalfa is the most promising irrigation 

 crop. Timothy also does exceptionally well 'HDelow the 

 ditch.'^ The grain crops are somewhat less suited 

 to irrigation in this climate, but respond well to the 

 timely application of water. 



192. Irrigating Timothy and Native Grasses. — The 

 management of these crops is perhaps less difficult than 

 that of any others now grown under irrigation in Western 

 Canada. The profit depends solely upon an adequate 

 supply of water evenly applied to the fields from the 

 time growth starts in the spring, which is early in May, 



