CONSERVATION OF SOIL MOISTURE 



care to sink the bottom of his well so far 

 below the level of the water-table that 

 seasonable changes will not cause it to go 

 dry. As a recent authority remarks, 

 "We must consider, then, that beneath all 

 farm soils, at some depth, there is stand- 

 ing water, and that we plow and har- 

 row above subterranean lakes." This is 

 a most important fact, because if it is 

 only a matter of one or two feet from the 

 surface of the land to the level of the so- 

 called soil-lake, there is evidently not 

 enough dry soil for the plants to grow 

 and thrive in, and consequently they are 

 liable to sicken and die off. The depth 

 of standing water most favorable to 

 crops cannot be definitely stated, since so 

 much depends upon the nature of the soil 

 and the roots of the crop. Thus, while 

 lucerne needs a fairly large amount of 

 water to do well, its deep-rooting habit 

 renders it undesirable that the "first," or 

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