Water and Watering 39 



be sufficient to throw the water through one-half the dis- 

 tance between the two lateral lines. The lateral pipe is 

 connected with a universal union near the elbow at the 

 top of the riser from the ground. This enables the 

 operator to turn the pipes resting on the posts in such a 

 way as to distribute the water evenly over a space about 

 50 feet broad. The cost of installing such a line will vary 

 with the amount and cost of large pipe and other material 

 needed, but $250 to $300 an acre is a sufficient amount to 

 allow for a 4- to 6-acre plant. 



Many of the plants run the laterals underground and 

 have one-inch risers, on the top of which are placed the 

 distributing nozzles. The distance between the distribut- 

 ing lines and the distance between the various risers on the 

 distributing line will vary with the make of nozzle used 

 and the pressure employed. This nozzle system requires 

 somewhat more piping than does the system with laterals 

 on the tops of posts. 



Surface irrigation. 



When a surface irrigation system is installed, it is 

 necessary to have the soil of a close compact nature. It 

 must contain a great deal of clay, otherwise the distribu- 

 tion of water in the vegetable field will be somewhat diffi- 

 cult and uneven. The field must also be quite even and 

 have a uniform slope. This system of distributing water 

 has been in vogue for so many centuries and in so many 

 different countries that it is hardly necessary to describe 

 it. The one difficulty to be overcome in the vegetable 

 field is that the water must be applied in furrows rather 

 near the rows of vegetables. For closely-planted vege- 



