PREFACE 



IN the preparation of this volume the author has 

 kept in mind the manifest need of giving more atten- 

 tion to the fundamental facts underlying agronomy, in 

 the present-day training of students in agriculture. 

 Such need has been felt directly by the author in his 

 organization of young men for agronomic and patho- 

 logic research. It is the occasional student who finds 

 himself prepared by sufficient training in those applied 

 sciences related to the study of field crops to meet the 

 awaiting problems of investigation. As the stream can- 

 not rise higher than its source, so the agriculture of the 

 future cannot be greatly improved unless the leaders 

 themselves are placed on a firmer scientific footing. 



From the above, it will be correctly inferred that 

 this book is intended primarily for instruction in col- 

 leges and universities. It will be a disappointment, 

 however, if it shall not be found adapted for use in 

 agricultural short-courses, academies, and high schools, 

 and by many farmers and general readers. 



The manner of presenting some of the subjects is very 

 different from that usually followed, but the changes 

 are considered well justified, and it is hoped will com- 

 mend themselves. After discussing briefly the funda- 

 mental principles of plant structure and nutrition, as 

 related to cereals, which subjects may be omitted by 

 those students who have had good training in plant 

 physiology, the four principal cereals are treated 



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