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(4) Drainage increases the amount of available 

 moisture in the soil and allows the roots to distribute 

 themselves over a greater area. TOien the soil is in good 

 tilth, the total capillary capacity is increased. The 

 soil is then in a condition to more easily absorb the 

 rainfall and to retain a larger proportion of it than is 

 the case in undrained soil. Also drainage lowers the 

 water table which is important since the roots won't pene- 

 trate below the drainage table. 



The depth to which the water level should be lowered 

 seldom exceeds 4 feet. The distance between drains de- 

 pends on the ease with which water will flow through the 

 soil toward the drain. Generally speaking, drains should 

 be placed between every second row on heavy soils and on 

 medium soils about every 300 feet. 



