364 DRY-FARMING 



face pacJving, are sound and in harmony with the 

 experience of the great dry-farm sections and with 

 the principles that are being developed by scientific 

 investigation. The "Campbell system" as it stands 

 to-day is not the system first advocated b}' him. 

 For instance, in the beginning of his work he adv'o- 

 cated sowing grain in April and in rows so far apart 

 that spring tooth harrows could be used for culti- 

 vating between the rows. This method, though 

 successful in conserving moisture, is too expensive 

 and is therefore superseded by the present methods. 

 Moreover, his farm paper of 1896, containing a full 

 statement of the "Campbell method," makes abso- 

 lutely no mention of "summer tillage," which is 

 now the very keystone of the system. These and 

 other facts make it evident that Mr. Campbell has 

 very properly modified his methods to harmonize 

 with the best experience, but also invalidate the 

 claim that he is the author of the dry-farm system. 

 A weakness of the "Campbell system" is the contin- 

 ual insistence upon the use of the subsurface packer. 

 As has already been shown, subsurface packing is of 

 questionable value for successful crop production, 

 and if valuable, the results may be much more easily 

 and successfully obtained by the use of the disk and 

 harrow and other similar implements now on the 

 market. Perhaps the one great weakness in the 

 work of Campbell is that he has not explained the 

 principles underlying his practices. His publica- 



