SOIL WATER 



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downward passage of water, or seepage, as it is called. 

 The water in seeping through the soil dissolves plant food 

 and if allowed to drain off would decrease the fertility of 

 the soil. Whatever decreases the porosity of the soil will 

 decrease the seepage and thus help to retain the plant 

 food. This may be done by adding humus, and sometimes 



AN ARTESIAN SPRING. 

 A deep water-layer has been pierced and the water diverted to the surface. 



where the soil is very porous by rolling. At the time 

 rain is likely to fall, however; the soil must be kept loose 

 and mellow so that the water can sink into it. 



Evaporation is, however, the cause of soil's losing the 

 greatest amount of water. Soil water is constantly mov- 

 ing toward the surface on account of capillary action, and 

 is being evaporated. This loss by evaporation must be 

 counteracted, if in arid countries or during dry spells 



