TEE IRRIGATION AGE. 209' 



ened. This method of irrigation is largely used for alfalfa, and hay- 

 ing machinery is readily worked over the levees, which are, of course, 

 covered with the plant as^well as the bottoms of Qthe^checks. It is 

 also used for grain growing, the levees being plowed, harrowed, and 

 reaped just as are the inclosed spaces. 



FLOODING IN RECTANGULAR CHECKS. 



Flooding in rectangular checks has been largely superseded by 

 the use of contour checks, except in orchard, vineyard, and garden 

 work. Unless the land is very nearly on a level, much earth has to 

 be shifted in making the rectangular inclosures, and the levees are of 

 irregular heights, while levees on contour lines are practically uni- 

 form. There is, consequently, greater difficulty in passing machinery 

 over them. For orchard and vineyard, where the rectangular ar- 

 rangement of the trees and vines continually interferes with contour 

 work, rectangular checks are widely used where the character of the 

 soil calls for flooding. ' They may be large, inclosing quite an area of 

 vines or trees, or they may be very small, even but 10 feet square. 

 This, of course, depends upon the grade of the land. 



For the growth of garden truck, also, the rectangular arrange- 

 ment accords with the rows in which such products are grown, and 

 Fig. 14 represents a typical scene in a market garden operated on this 

 system. In such cases the laying off is temporary, as when the crops 

 are gathered, or at the end of the season's succession of crops, th& 

 levees are plowed down, and then the whole field thoroughly plowed 

 and harrowed and the levee system restored, sometimes by backing 

 furrows each way, and finishing with hand tools or by using a ridger. 

 etc., pictured and described in a previous farmers' bulletin.^ 



In small gardens it may be thought better to retain the levee sys- 

 tem and work the bottoms of the checks with fork or spade, accord- 

 ing to the usual methods of hand-power gardening. In field work on 

 level land the checks may be so large that teams are used inside the 

 levees, and in that case the irrigation arrangements are permanent. 

 Whether, however, the levees be temporary or permanent, the water 

 is applied about the same way already described for the contour-check 

 system. 



In the most satisfactory work in rectangular checks the check 

 bottoms are approximately leveled by scraping the hummocks into the 

 low places, using surplus dirt for the levees. Grading or leveling is 

 very desirable, and the initial cost is returned many times over in the 

 ease and satisfaction with which the water is evenly distributed inside 

 the check. This is often done by running small furrows between the 

 plants in the check bottoms so that the water is led this way and that 

 until all the plants are equally supplied. 



1 See U. S. Department of Agriculture, Farmers' Bulletin 116. 



2 See U. S. Department of Agriculture, Farmers' Bulletin 116. pp. 30, 31. 



(To be continued.) 



