Drainage in New York. 



251 



III. BENEFITS OF THOROUGH DRAINAGE. 



Because of the fundamental character of the process of drainage, Its 

 effects are numerous and far reaching. Ten of the most important may 

 be given as follows : 



(i) Drainage removes the excess of zcater from the surface and from 

 the pores in the soil thereby rendering it more firm. The presence of the 

 excess of water renders the soil unable to support any considerable weight, 

 because the moisture acts as a lubricant between the soil particles per- 

 mitting them to move freely upon each other. Therefore, such soil is soft 

 and boggy. 



Fig. 194. — All inter-hill area of innch soil in IVaync county greatly in need of 

 better drainage. The flooded condition is the result of a poorly constructed 

 outlet ditch. 



This same free movement of the particles is exceedingly injurious on 

 all except sand or gravel soil because of the undersirable physical condi- 

 tion brought about. The small particles are moved into the spaces between 

 the larger ones, thereby forming a more dense mass of soil. This is 

 known as the puddled condition and when such soil is permitted to dry 

 naturally it becomes exceedingly hard and refractory. Such a condition 

 is generally recognized as undesirable. It is directly opposed to the granu- 

 lar condition of the soil where the particles are grouped in small aggre- 

 gates and which favors the production of good " tilth." Poorly drained 

 soil, therefore, has the two-fold disadvantage of lack of stability or firm- 

 ness and great susceptibility to physical modifications injurious to most 

 farm crops. Such injury may be caused by any tillage operations, by 

 tramping and by the natural drying of the soil. 



