306 IRRIGATION PRACTICE 



gated by the furrow method. It uses little water. The 

 soil should be moist at planting, and the crop usually 

 receives but one irrigation after planting. 



183. Hops. Hops is another valuable crop, which is 

 grown to a limited extent under irrigation. In the humid 

 hop-growing sections, supplementary irrigation is a very 

 common practice. Hops are easily grown, and are irriga- 

 ted by either the furrow or the flooding method. Water 

 is applied every three or four weeks. The heaviest ift|ga- 

 tions are given as the buds appear. No irrigation is appliecJ 

 after August 15, when the crop is about to ripen. 



184. Tomatoes, cantaloupes, etc. These and similar 

 crops do excellently well under irrigation. Tomatoes, 

 especially, have become a very important crop as canning 

 factories have been established. The plants are set out in 

 rows in the usual way, and the water is applied invariably 

 by the furrow method. If careful cultivation is applied 

 to the irrigated field, the tomato plant does not demand an 

 excessively large quantity of water. Too much water 

 encourages too great a growth of vines, and interferes 

 with ripening. The first irrigation is postponed as long as 

 possible after planting, and, when the irrigation season 

 begins, three irrigations are usually sufficient for the sea- 

 son. Heavy irrigation at the time of ripening tends to 

 increase the weight of the crop, and farmers who supply 

 the canning factories, therefore, apply at that time large 

 quantities of water; so large, indeed, that growth is stopped 

 and the ripening fruit is well filled with water. In other 

 places, at the time of ripening, water is refused the plant 

 entirely, leaving excellent fruit, although the total weight 

 is not so great. During picking it is a common practice to 

 apply water largely, with the result that the yield is 

 increased. The cultivation of tomatoes throughout the 



