Journal of Agriculture. 



[8 Feb., 1908. 



PREPARIXG LAND FOR IRRICIATIOIs. 



Elwood Mead, Chairman, State Rivers and Water Sup-ply Commission. 



The large number of inquiries recently received by the State Rivers 

 and Water Supply Commission about preparing land for irrigating lucerne 

 has rendered it impossible to make adequate reply by letter. This article 

 has been prepared to serA'e as a substitute. It is based on American prac- 

 tices, being taken, with slight modification to suit Victorian conditions, 

 from the Irrigation Bulletins of the U.S. Office of Experiment Stations. 

 The illustrations are also taken from the same source. 



Methods of Irrigating. 



Five methods of watering lucerne suited to the soil and conditions of 

 Victoria will be considered. These are : — 



1. Flooding by Contour Channels. 



2. Flooding by means of Contour Checks. 



3. Flooding by means of Rectangular Checks. 



4. Flooding by means of Borders. 



5. Percolation from small Furrows. 



I. Flooding from Contour Channels. — This is the oldest and 

 simplest form of field irrigation and consists in turning the water upon 

 the land from contour channels, or channels having small grades, either 

 by damming the channel and letting the water flow over its bank or by 

 making spade cuts at intervals along the bank. 



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In irrigating lucerne these field channels are run out from head or 

 supply channels from 2 to 4 chains apart on a grade of from i to 3 inches 

 to the chain. These channels are large enough to carry a good irrigation 

 head, that is, as much water as an irrigator can distribute evenly. This 

 will varv from 100 to 250 cubic feet per minute. The field channels or 

 laterals should be ploughed out the time the crop is planted. They may 

 be maae bv ploughing two furrows away from each other or by using a 

 double mould-board plough. (Fig. i.) 



