i66 



Nature-Study Agriculture 



Furrow 



irrigation; 



advantages 



Arrange- 

 ment of 

 furrows 



Check 

 flooding 



FIG. 130. Furrow irrigation near Richland, Idaho. 



grow down. And deep-rooted plants get more plant food 

 and do not suffer so much from an occasional dry spell. 



Running the water in furrows between the rows is 

 usually more satisfactory than sprinkling (Fig. 130). 

 It wets deeper than sprinkling often does, and as it 

 leaves the foliage dry it does no harm on a hot day. 

 The water in the furrows should run slowly enough so 

 that it will just reach the lower end of the row before 

 the last of it sinks into the ground. In watering or- 

 chards several furrows are made between two rows of 

 trees, but in watering such a crop as potatoes one furrow 

 for every other row is sufficient if the water is allowed 

 to run long enough. The best way to make sure that 

 all the ground is wet to a sufficient depth is to use 

 a spade. 



The check system of flooding a field is suitable only 

 where the ground is nearly level. Before the crop is 



