14 CULTIVATION METHODS AND KOTATIONS FOR GREAT PLAINS. 



CONTINUOUS CROPPING COMPARED WITH ALTERNATE CROPPING 

 AND SUMMER TILLAGE. 



GENERAL STATEMENT. 



Before entering into a discussion of the subject of continuous 

 cropping compared with alternate cropping and summer tillage, it 

 will be well to clearly set forth some important considerations that 

 must be constantly borne in mind. They are as follows: 



(1) The discussion applies to the Great Plains area only and can 

 have no possible bearing upon practices in regions west of the Rocky 

 Mountains, where soil and climatic conditions are radically different. 



(2) These experiments were made with spring-sown grains only and 

 have no bearing whatever upon the methods applicable to fall-sown 

 grains. 



(3) The object of the work described under this heading is to test 

 the relative merits of three systems of one-crop farming, namely, (1) 

 ordinary methods; (2) moisture-conservation methods of contin- 

 uous cropping; and (3) summer-tillage methods of alternate or bi- 

 ennial cropping. This part of the work has nothing whatever to do 

 with crop rotation, except possibly to show that no system of one- 

 crop farming has yet been devised that can serve as a safe basis for a 

 permanent agriculture in the Great Plains area. A discussion of 

 crop rotation is given under another heading (p. 20). 



The general plan of that portion of the investigations herein 

 described is identical for all of the eleven stations and is as shown 

 in the accompanying outline and the explanatory notes following: 



Outline of plan for experiments with three staple cereal crops with ordinary methods of 

 culture and with moisture-conservation methods, each crop being grown on the same 

 plat for several years either continuously or alternating with summer fallow. 



EXPERIMENTS WITH WHEAT. 



Wheat grown year after year on spring-plowed land by ordinary methods of 

 culture. 



Wheat grown year after year on fall-plowed land by moisture-conservation 



methods of culture. 

 Wheat alternating with summer tillage. 

 Summer tillage alternating with wheat. 



EXPERIMENTS WITH OATS. 



Plat A. Oats grown year after year on spring-plowed land by ordinary methods of 

 culture. 



PlatB. Oats grown year after year on fall-plowed land by moisture-conservation 



methods of culture. 

 Plat 0. Oats alternating with summer tillage. 

 Plat D. Summer tillage alternating with oats. 

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