CEREAL CULTIVATION GREAT PLAINS 353 



was found that summer tillage without a crop gave the 

 highest average yields of spring wheat following it at 

 twelve of the fourteen stations where the experiments 

 were conducted, but on account of its high cost it had not 

 been the most profitable practice. 



Oats did best after summer tillage at all stations except 

 Hettinger, North Dakota, where disked corn ground gave 

 a better yield. It is concluded that " the degree of as- 

 surance which summer tillage affords against failure of 

 the feed crop might justify its practice in oat production 

 in at least some sections of the Great Plains." 



In barley production, summer tillage gave the highest 

 average yields at eleven of the fourteen stations. On the 

 average it increased the yields nearly half over those pro- 

 duced on land cropped the preceding year. Yet because 

 of its cost, it has not been the most profitable method. 

 The yields in continuous cropping generally average a 

 little more than two thirds as much as after summer 

 tillage. 



There appears to be greater response to summer tillage 

 by winter wheat in the winter wheat district than by 

 spring cereals in the spring wheat district. 



In the report on dry-farming investigations in western 

 North Dakota previously referred to (368, 374), it is stated 

 " that alternate cropping has not proved to be a profit- 

 able practice at any of the North Dakota stations where 

 this work has been conducted, except at Dickinson. A 

 strong argument in favor of summer tillage is that, in a 

 certain measure, it insures a fair yield in a season of 

 drought, but when considered from the standpoint of 

 average production, it appears that it is of doubtful value 

 in western North Dakota." 



Four years' results have been obtained at the Hays, 



2A 



