270 SOILS 



TILLAGE AFTER IRRIGATION 



When the crop will permit the land should 

 be tilled after each irrigation. This is especially 

 necessary in the case of orchard fruits, small fruits, 

 corn, potatoes and garden vegetables. Irrigation 

 leaves the surface soil more or less puddled; when 

 this dries it becomes hard and, if clay, it may crack. 

 These conditions are very favourable for a rapid 

 loss of water which, if unchecked, may easily 

 amount in a few days to a large per cent, of the 

 water that has been applied. 



Amateurs in arid farming often have a notion 

 that all that is necessary is to irrigate often enough 

 to keep the soil moist, and that tillage is therefore 

 unnecessary. The fact is that tillage is about as 

 important in arid farming as in humid farming. 

 In the first place excessive irrigation makes many 

 crops sappy, over-vigorous and unsubstantial. 

 This is especially true of fruits. In the second 

 place it is good economy to use as little water as is 

 necessary to secure the best results, for water is 

 expensive to secure and laborious to apply. In 

 the third place a soil that is kept as continuously wet 

 as would be necessary in order to grow crops with- 

 out tillage between irrigations, is not in the best 

 condition for maintaining its fertility. A certain 

 amount of dryness in the surface soil promotes the 

 development of soil bacteria and other agencies 

 that have an important influence on the pro- 

 ductivity of the land. As men become more ex- 

 perienced in the use of water they almost invariably 

 decrease the amount applied and increase the fre- 

 quency and thoroughness of the supplementary 

 tillage. One does not need to grow crops many 

 years in order to learn that there is nothing that can 

 take the place of stirring the soil. 



