PREFACE 



This book is designed primarily to meet a growing demand for 

 definite, practical and complete information concerning soils and 

 profitable crop production. This, therefore, is a book of fundamen- 

 tals, and hence applicable to a wide range of country. The basic 

 facts concerning soils, and the fundamental principles of success- 

 ful soil management are essentially the same everywhere, but the 

 method of application must necessarily vary because of different 

 climatic conditions. 



This text represents an extensive experience on the part of the 

 author — ^from practical farming before and after college gradua- 

 tion to university teaching and Extension Service. It is hoped 

 that the facts and principles herein presented will lead the prac- 

 tical farmer and the student into a broad field of interesting and 

 profitable knowledge. 



To one who is familiar with the crimibling of the soil as it moves 

 over the moldboard, these chapters will not be entirely new and 

 strange, but will present things both new and old. It is the hope 

 that the new and the old are presented in such a way as to elim- 

 inate the difficulty too often experienced by searchers after the 

 fundamentals — ^namely, the failure to place the facts and prin- 

 ciples in their true relation to successful farm practices — a dif~ 

 ficulty which has been the result of a lack of proper organization 

 and correlation of the subject matter. 



In his teaching of many hundreds of farm boys as well as prac- 

 tical farmers, the author has had the opportunity to test out vaii- 

 ous methods of instruction and arrangement and correlation of the 

 subject matter. Actual results have been the only guide in deter- 

 mining the best plan. Even after this course of study was fully 

 completed it was thoroughly tried out on several classes before it 

 was put into publication. The plan of the book may readily be 

 seen by studying the Contents. 



Special effort has been made to present the subject in as simple 

 a form as possible while making it complete and authorita- 

 tively correct. 



It is impossible to mention the many original papers, 'research 

 data and other agricultural literature consulted. 



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