INDEX. 



77 



Page. 



North Dakota, cropping methods, various grains, average yield and value per 



acre, 1900-1909 26-27 



various grains, average price per bushel, 1900-1909 25-26 



Oats, average price per bushel in various States, 1900-1909 .' 25-26 



comparison of disked corn stubble with summer tillage as preparation for 



crop 45-48 



average value per 

 acre 45-48 



continuous cropping, average yield and value per acre, 1900-1909 27-28 



comparison -with alternate cropping and summer 



tillage, experiments 14-20 



crop-rotation tests, average yield and value per acre, 1906-1909 28-34 



rotations, comparison 20-40 



with continuous cropping, value per acre ... 38, 40-45 

 yield per acre ... 37, 40-45 



cropping systems, comparison of yields per acre 17, 18 



relation, to summer tillage in three-year rotation 51-52 



tillage methods, average production per acre, studies 8-12, 67-72 



various cropping methods, average yield and value per acre, 1900-1909 . . 26-27 

 wheat, and corn a less desirable sequence on spring plowing than wheat, 



oats, and corn . 52-54 



One-crop farming. See Farming, one-crop. 

 Organic matter. See Matter, organic. 



Plowing, corn stubble, comparison with disking, for spring wheat 49 



deep, comparison with shallow plowing 20 



fall, comparison with spring plowing 50-51 



shallow, comparison with deep plowing 20 



spring, comparison with fall plowing 50-51 



Precipitation, Great Plains area, record by months, 1904-1909 72-74 



Rainfall. See Precipitation. 



Rotation, crops. See Crops, rotation. 



South Dakota, cropping methods, various grains, average yield and value per 



acre, 1900-1909 26-27 



various grains, average price per bushel, 1900-1909 25-26. 



Snyder, W. P., and Burr, W. W., article on summer tillage 71-72 



Soil, conservation of organic matter, description of rotations 55-65 



Stubble, corn. See Corn, stubble. 



Tillage, methods, comparison with crop-rotation systems, studies and experi- 

 ments 8-12,67-72 



definition of terms 15 



Great Plains area, effect of local conditions, study 9-10, 27, 65 



various grains, average production per acre, studies 8-12, 67-72 



summer, and continuous cropping arid regions, conclusions 18-20 



article by W. P. Snyder and W. W. Burr 71-72 



comparison with continuous cropping and alternate cropping, 



experiments 14-20 



disked corn stubble as preparation for wheat 



or oat crops 45^8 



experiments, conclusions 67-72 



relation of wheat and oats in three-year rotation 51-52 



responsibility for increase of crop yield in arid regions, study. . 13- 



187 



