6 PREFACE 



should be given to the particular crops which are of impor- 

 tance in the region where the instruction is given. Fre- 

 quent visits should be made to farms in the vicinity, and as 

 many of the crops as possible studied at first hand. Small 

 plats of some crops not common in the community may well 

 be grown on the school farm to supply illustrative material. 



While the book is designed primarily for text use, the 

 authors trust that it will also be of interest to farmers and 

 to those who desire to become farmers. The results of many 

 experiments have been embodied in the text, as have also 

 the practical experiences of many good farmers. The aim 

 throughout has been to make a simple, practical, readable 

 manual. 



Our acknowledgments are due to various officials of the 

 United States Department of Agriculture, and to the Ohio, 

 Kansas, and Minnesota experiment stations for illustrative 

 material. 



A. D. WILSON. 



C. W. WARBURTON. 



St. Paul, Minn., July, 1912. 



