INTRODUCTION xix 



ture must restore it; and the restoration must begin while some 

 farmers are still prosperous, for poverty-stricken people are at 

 once helpless and soon ignorant. Outside help will always be 

 required to redeem impoverished soils, for poverty makes no in- 

 vestments, and some initial investment is always required for soil 

 improvement. 



It is the purpose of this book to teach the science of soil fertility 

 and permanent agriculture, chiefly by reporting facts rather than 

 by offering theories; and any one of common sense who reads the 

 English language, and who can understand the common school 

 arithmetic, can understand this book if he will study it. (The 

 fact may well be recognized that some who have ample time for 

 study, though physically industrious, are mentally lazy. 1 ) 



The author suggests, however, that the busy farmer, who 

 wishes to familiarize himself as quickly as possible with the most 

 essential practical facts pertaining to the economical and perma- 

 nent improvement of common or normal soils, and who is willing 

 to pass over temporarily the discussion of foundation principles, 

 may well begin the study of this book with " Systems of Perma- 

 nent Agriculture," Part II, after first making the following facts 

 a part of his ever ready knowledge: 



(1) Phosphorus and decaying organic matter are the two sub- 

 stances which constitute the key to profitable systems of permanent 

 agriculture on most of the normal soils of America ; although, 

 when soils become sour, or acid, ground natural limestone should 

 also be regularly applied, at the rate of about two tons per acre 

 every four to six years. 



(2) There are six essential positive factors in crop production: 

 the seed, a home for the plant, the food of which the plant is made 

 (and this factor is just as important for plants as it is for animals) , 

 moisture, heat, and light. Of these six factors, the least appre- 

 ciated and the most neglected is that of plant food, and yet this 

 is a factor which the farmer can very largely control, whereas the 

 others (except the seed) are largely beyond his control. (An 

 important negative factor is protection from weeds, insects, and 

 disease.) 



1 " Many poor farmers have a lazy faith in the Lord ; they think or hope that 

 He will somehow make up for whatever they fail to do." HOARD. 



