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DRAINAGE 



depth of several feet, and the plants with their roots 

 near the surface will surfer from the drought. In land 

 with proper underdrainage the ground water is not 

 near the surface at any time, and the roots of the crop 

 sink deeper into the soil and thus have a greater depth 

 of soil from which to get the food materials ; and the 



DRAIN TILES 



greater root depth also enables the plants to get a larger 

 supply of moisture during a dry season. 



Roots need air. It must be remembered that the 

 roots of plants need air, and that free water in the soil 

 excludes the air. In drained soils, as the water passes 

 from the soil into the ditch the air enters the pores of 

 the soil to replace the water. Thus good drainage 

 admits air to the soil and roots. 



