ILLUSTRATIONS 



For illustrations the author wishes to acknowledge the fine assis- 

 tance of Mr. Hermann Postlethwaite, photo editor, and his assistant, 

 Mrs. Elizabeth B. Elmore, of the U. S. Soil Conservation Service. 

 From SCS files came the following : 



Frontispiece (2), Figs. 1, 2, 4, 5, 6, 7, 10, 14, 15, 16, 17, 18, 19, 20, 

 22, 23, 24, 25, 26, 38, 39, 40, 41, 42, 44, 45, 46, 50, 51, 53. 



The U. S. Forest Service supplied Figs. 21, 43, 52. 



The U. S. Strategic Bombing Survey, Fig. 3. 



The Issac Walton League of America, Figs. 47, 48, 49. 



Dr. William A. Albrecht, the University of Missouri, Figs. 8, 9, 

 11, 12, 13. 



By the author, Figs. 27 through 37. 



