92 SOILS AND FERTILIZERS 



in the bottom through which the water may find vent. Set the can 

 in a dish, pour water on the soil from the top, and test that which 

 drains through with the litmus paper. 



Methods of Irrigation. Various approved methods 

 of applying water by irrigation are in use in different 

 regions, but those most used are sprinkling, flooding, 

 furrowing, and tiling. 



Sprinkling. Of the four methods named, sprinkling 

 most nearly resembles the means by which nature 

 furnishes water to growing plants. In spite of this fact, 

 sprinkling is the poorest of the methods named. To 

 apply a sufficient amount of water at one time by this 

 method requires a very slow application, for, if applied 

 too rapidly, the ground, if it is not sandy, becomes packed 

 and hardened. In this condition sufficient air, which 

 the plant needs, cannot get through the soil and the 

 penetration of the roots is also difficult. There is also 

 very rapid evaporation from the surface unless the soil 

 is stirred soon after sprinkling. This results in great 

 waste of water and renders a second application neces- 

 sary in a short time. If practiced in a region where 

 there is no rainfall through the summer, it must be 

 repeated often and a sufficient amount given to saturate 

 the soil to a considerable depth ; otherwise, the plant 

 will develop a shallow root system and will be largely 

 dependent upon water thus applied all through the 

 growing season. 



Flooding. By this method water is spread over the 

 field in as even a sheet as possible. It can be used only 

 where an abundance of water is available and where the 

 land to be irrigated is naturally quite level or can be 

 made so. As in the case of sprinkling, there will be 

 rapid evaporation unless the surface of the soil is 



