THE AFTER-CULTIVATION OF CROPS 169 



have the same effect as weeds; namely, they oc- 

 cupy the soil and take plant food and moisture 

 which if left to fewer plants would produce a 

 larger harvest. 



HILLING AND RIDGING 



Except in low, wet ground, the practice of hilling 

 or ridging up crops is now considered by those who 

 have given the matter thorough study, to be un- 

 necessary, flat and shallow culture being cheaper. 

 It saves more moisture, and for this reason, in the 

 majority of cases, produces larger crops. 



Sometimes during very long-continued periods of 

 wet weather weeds and grass become firmly estab- 

 lished among the plants of the crop. Under such 

 circumstances it is necessary to use on the culti- 

 vator teeth having long, narrow sweeps that will 

 cut the weeds just beneath the surface of the soil. 

 Sometimes a broad-toothed tool is used that will 

 throw sufficient soil over the large weeds near the 

 rows to smother them. 



The condition to be met and the effect of the op- 

 eration should always be given serious thought. 



We have considered after-cultivation as influenc- 

 ing soil fertility by checking a loss of water by evap- 

 oration and weed transpiration, and this is its main 

 influence but other benefits follow. 



Keeping the surface soil loose and open benefits 

 fertility because it directly aids the absorption of 



