INTRODUCTION 3 



not already enough acres of abandoned agricultural lands in this 

 country? The United States does not stand first in yields per acre, 

 but it does excel all other nations in rapidity of soil exhaustion. 



Nationally and individually, the time to adopt methods to 

 maintain productiveness and to improve our soils is while we are 

 prosperous. This task challenges every tiller of the soil, every 

 farm boy and girl, the dwellers in cities, every agricultural organ- 

 ization, and all other forces which strive for betterment through 

 human endeavor. No greater force can man set into action than 

 the power of the intellect — and this is accomplished through edu- 

 cation. Then let it be education. 



The general sentiment among thinking farmers is — "How 

 little we know about soils and how much there is to know ! ' ' These 

 farmers have not had the opportunities for agricultural training 

 existing today. They cannot now go to school, hence instruction 

 should be carried to them. This information, as well as that given 

 to students in all practical or first courses, should not be technical 

 and lop-sided, but simple, practical and well-balanced so as to 

 enable our present-day farmers and those of the future to gain a 

 happy living, and at the same time to conserve the great funda- 

 mental asset of our Country — ^the soil. 



TO THE TEACHER 



It may not be necessary, or time may not permit, to perform 

 all the exercises indicated. Only those should be selected which 

 will best supplement the class work. Frequently it becomes 

 necessary to combine class work, demonstrations and laboratory 

 exercises, or to make the laboratory exercises demonstrational. 

 Local conditions should determine in a large degree the exercises 

 to be selected. Those listed here may suggest others more suitable 

 to local conditions. 



Field trips should be carefully planned to include as many 

 observations as possible. The leader, or teacher, should first go 

 over the ground alone in order to map out the trip and determine 

 what observations are to be made. 



The materials needed for demonstrations and laboratory work 

 are based on one demonstration or exercise. 



The demonstrations which require time before the results may 

 be shown should be started in time to be ready when needed. 

 (Note demonstrations for Chapters V, VI, VII, VIII, IX, XI, XII.) 



