CONTENTS 



Preface 



List of Illustrations 



PAGE 



vii 

 xix 



CHAPTER I 



Introduction — Drt-farming Defined 1_10 



Dry- vs. Humid-farming .4 



The Problems of Dry-farming .6 



CHAPTER II 



The Theoretical Basis of Dry-farming . . . 11-21 



Water required for One Pound of Dry Matter , . .12 

 Crop-producing Power of Rainfall 18 



CHAPTER III 

 Dry-farm Areas — Rainfall ...... 22-34 



Arid, Semiarid, and Sub-humid 24 



Precipitation of the Dry-farm Territory of the United States 25 



Area of the Dry-farm Territory of the United States . . 2(3 



Dry-farm Area of the World ' 32 



CHAPTER IV 

 Dry-farm Areas — General Climatic Features . . 35-49 



Seasonal Distribution of Rainfall 38 



Snowfall 42 



xi 



