viii PREFACE 



This course of study in the complete edition is designed to 

 give it wide adaptation, to wit : 



(a) It may serve as a farmers' ready reference, or as a prac- 

 tical guide in successful soil management. 



(6) In college short courses, and normals, the whole course as 

 it is planned may be given. The object of each student should 

 be to master the fundamentals. 



(c) In college long courses, this text in the hand of the first- or 

 second-year student may supply him with the fundamentals, leav- 

 ing the lecture hour free to the instructor for elaboration, for 

 application of facts and principles to local conditions, and for the 

 presentation and discussion of experimental and research data. 



The subject of Soil Management and Crop Production is truly 

 large enough and of sufficient importance to be given a place in 

 every agricultural curriculum. This subject should precede or may 

 be given at the same time as the allied subject, Farm Crops. The 

 latter subject could then be made a study, not so much of soils in 

 relation to growing the crops, but rather of crop characteristics, 

 crop importance, types, varieties, judging of grains, seed pro- 

 duction, special cultural methods, harvesting, and care of crops 

 and grains. 



At the close of each chapter suggestions are offered for demon-, 

 strations, laboratory exercises, and for home experiments and 

 projects. Many questions and practical problems are also given. 



The author wishes to express his appreciation to Prof. E. Truog 

 of the Department of Soils, and to Prof. J. A. James of the Depart- 

 ment of Agricultural Education, University of Wisconsin, for care- 

 ful reading and approval of the manuscript; to Prof. E. R. Jones, 

 University of Wisconsin, for verifying the chapters on water rela- 

 tions and drainage; to Prof. C. F. Marbut, in charge of soil survey, 

 Bureau of Soils, United States Department of Agriculture, for 

 valuable suggestions concerning soil types and for approval of 

 that part of Chapter II relating to that subject. 



W. W. WEIR. 

 MADISON, Wis. 

 January, 1920 



