xx LIST OF ILLUSTRATIONS 
NO. PAGE 
27. Alway’s experiment, showing relation between crop and soil- 
moisture . bd Jest. Uses” fe Pa ee a Se 1 
28. Water insmall tubes . F . . . 104 
29. How rainwater is changed to caving soil-watox . . 110 
80. Soil-water in fallandinspring . * : . . - 115 
31. Kubanka wheat field in Montana . . . . a . 7 
82. Annual rainfall and evaporation compared . . « . 181 
83. Checked land s . : : : . . . 142 
34, Alfalfa in cultivated rows . . p is . . - 1651 
35. The effect of cultivation Fe ne ee ee ee ee eee | 
36. Flaxin Montana . . 5 
37. Plowing in the Northwest . . . . < . . 161 
38. Root-hairs and soil particles . . - . ‘ ‘ . 167 
89. Penetration of root-hairs through soil . . . . . 169 
40. Wheat roots with soil particles . E . . . . ii 
41. Stomata. . - : . . . . . 178 
42. Photograph of toniaty a F : is . 
. . . 173 
43. Ideal tilth of soil : ‘ . 5 - 181 
44, Interior of olive orchard in Sfax, Tunis F F 5 . 184 
45. Winter wheat in Wyoming . : : . . . - 189 
46. Dry-farm potatoes, Montana é ‘ 5 . . . 190 
47, Clean summer fallow . ‘ S : 7 . . 196 
48. Barley on land continuously cape . . . . 199 
49, Barley on summer fallowed land . . . - . . 201 
50. Combined harvester and thresher, Montana . E . . 211 
51. Header at work, Washington ° F : . 218 
52. Cultivating oats with weeder, Wronine . 5 : . 219 
53. Header at work 2 5 . . 229 
54. Oat field, Utah : . : 4 . 231 
55. Winter wheat and alfalfa, Wivomnitie . . . . » 235 
56. Turkey wheat field, Montana . = : . s . 239 
67. Barley field, Nevada: is ° ‘ ‘ . 242 
58 Corn field, New Mexico fs « ‘ a . 246 
59. Oat field, Montana a ‘ ‘ : 4 . i . 250 
60. Ears of corn, Montana . . 7 . 5 . ° . 255 
61. Heads of macaroni wheat . . . - s . . 259 
62. Heads of hard winter wheats : si . . . 265 
63. Milo maize field, Montana . . ‘ = . . . 266 
