662 SOILS: PROPERTIES AND MANAGEMENT 



and far-reaching. In its accomplishment the physical 

 properties of the soil and its moisture relations must be 

 taken into account. Whether open ditches or under- 

 drains are employed depends on the local conditions, but 

 where practicable underdrains are always to be chosen. 

 While the cost of drainage is a considerable sum, the 

 improvement when well made is of long duration and the 

 cost may therefore be distributed over a long period. 

 The benefits accrue not only in increased crops, which 

 are generally large, but also in the saving of expense in 

 operation. Good drainage is the basis of good soil 

 management. 



