342 



SOIL PHYSICS AND MANAGEMENT 



3. The turning under of rubbish is essential to good plowing. 

 To do this properly the furrow-slice must be five or six inches thick, 

 and in some cases chains or weed hooks are necessary. 



4. The furrow should be kept straight or at least parallel with 

 the middle ridge, as a crooked furrow almost always indicates 

 " cutting and covering " at some points. 



1. Time of Plowing. The time when plowing should be done 

 varies with climatic, crop, and soil conditions. In semi-arid regions 



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FlO. 162. Good plowing in stubble land. (.lanesville Machine Company.) 



Fia. 163. A crooked furrow docs not look well, even if the plowing is good. 



