CULTIVATING AND CROPPING 



of the relative desirability of these systems 

 we must again turn to underlying principles and 

 purposes. 



It may be said on first thought that tillage 

 Is a practice contrary to nature. But It ac- 

 complishes what nature does In another way. 

 Tillage has been practiced on other crops than 

 trees for so long that we think of It almost 

 as a custom. There are, however, scientific 

 and practical reasons for tillage. 



The Effects of Tillage on the soil are 

 three fold, physical, chemical, and increasing of 

 water holding capacity. Tillage affects the soil 

 physically by fining and deepening It, thus In- 

 creasing the feeding area of roots, and by bring- 

 ing about the more free admission of air warms 

 and dries the soil, thus reducing extremes of 

 temperature and moisture. Chemical activ- 

 ities are augmented by tillage in setting free 

 plant food, promoting nutrlfication, hastening 

 the decomposition of organic matter, and the 

 extending of these agencies to greater depth. 

 Tillage conserves moisture by Increasing the 

 water holding capacity of the soil and by check- 

 ing evaporation. 



Of all these things which tillage accomplishes 

 in a soil, two should be especially emphasized 



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