FARM IRRIGATION 271 



METHOD OF IRRIGATING IMPORTANT CROPS 



Methods of irrigating different crops by flooding 

 and by furrows are endlessly varied in different 

 sections to suit the needs of different crops. The 

 following are common methods of handling a few 

 of the most important irrigated crops. 



Meadows, Including Alfalfa. These are irrigated 

 largely by flooding, usually once in early spring 

 before growth starts, and once after harvesting 

 each crop. If irrigation is given more frequently 

 than this, it should be some time before the time 

 to cut the grass, so that the ground may be firm 

 then. Irrigated meadows should usually be cut 

 rather than pastured. Unless the ground has been 

 allowed to become quite dry, animals are likely to 

 roughen the surface and increase the difficulty of 

 flowing water over it evenly. The amount of water 

 used in irrigating meadows cannot easily be ex- 

 cessive. Under sewage irrigation, on the water- 

 meadows of Italy, from 40 to 70 tons per acre 

 are cut each season. These meadows are irri- 

 gated by a thin sheet of water running over 

 them almost continuously, night and day, during 

 seven months of the year, amounting to over 

 three hundred feet of water per year. Water is 

 turned off only long enough to cut the six or seven 

 crops of grass, which grows the year around. 



Tree Fruits. Most orchard irrigation is by 

 furrows. The prevailing method is to lead the 

 water through very narrow furrows four or five 

 feet apart, allowing it to soak four or five feet 

 deep and to spread between the furrows beneath 

 the surface mulch before the supply is cut off. It 

 is sometimes recommended that the furrows be 

 run on the shady side of the trees so that 



