AUTHOR'S PREFACE 



THE low yields of farm crops in this country are 

 frequently used as a basis for speculation as to the 

 future limit of food supply. The causes for these 

 low yields are variously estimated. Bad management, 

 over-cropping, loss of soil fertility, washing away of 

 soils, "changing climatic conditions," and even "over- 

 drainage " are among the more prominent of the causes 

 named. " Bad management " is a very comprehensive 

 term. " Loss of soil fertility " is a much used expres- 

 sion, but indifferently understood. Sometimes it is 

 properly applied, but in many cases it probably does 

 not apply except in so far as it may be synonymous 

 with malnutrition of the crop. 



The improper functioning of common soils, because 

 of the extended presence, at some time during each 

 year, of excessive amounts of water, is seldom men- 

 tioned ; and yet one needs but to travel through the 

 land with an observant eye in the cropping season to 

 discover areas (even in the so-called " garden spots ") 

 where half stands exist, fourth stands, and actually no 

 stands for a half field or whole field, indicating failure 

 in germination or very soon thereafter. He discovers 

 sickly full stands, half stands and less; also drowned 

 areas, and places where no crops have been planted 

 " skipped areas " in fields that in other parts have 

 a thrifty appearance of crops. 



It is difficult, indeed, to estimate the losses resulting 

 from such conditions. There can be no doubt that if 

 many of these fields could function as well over their 

 whole areas as in their best parts, their average yields 



