ILLUSTRATIONS 



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1. Diagram, proportion of space occupied by soil material, water and air. . 5 



2. Diagram, texture, composition of soil g 



3. Baked and cracked soil g 



4. Cutting, pulverizing and compacting the seed bed 10 



5. Pans of clay soil H 



6. Diagrams, effect of deep plowing 13 



7. Plank drag 15 



8. Corrugated roller 16 



9. Plowing under green manure 21 



10. Nodules on roots of alfalfa 22 



11. Value of fertilizers 27 



12. Lime and fertilizer, comparative study 30 



13. Undei'drains placed 36 



14. Types of drainage tile _ 37 



15. "Random" drainage 38 



16. System of drainage 39 



17. System of drainage, double drained land 40 



18. Ditching plow 43 



19. Tools for ditching 44 



20. Regions of corn 49 



21. Wheat regions 66 



22. Leading varieties of hay 85 



23. Geography of the world's agriculture 85 



24. Soil in good tilth 88 



25. Kentucky blue grass 94 



26. Canada blue grass 96 



27. Two-year old alfalfa plants 104 



28. Where alfalfa is grown 105 



29. Soy bean 106 



30. Cutting the potato 110 



31. Production from seed Ill 



32. Potato producing areas in U. S 112 



33. Notched-platform potato planter 115 



34. Elevator potato digger 115 



35. Colorado beetle '. 116 



36. Potato disease 117 



37. Traction spraying of the potato 118 



38. Area adapted to growing sweet potatoes 120 



39. Sweet potato slips ready to be drawn 123 



40. Sweet potato tuber and sprouts ' 125 



41. Black-rot of sweet potato ■ 126 



42. Soft-rot of sweet potato 127 



43. Black-rot on plant 128 



44. Cigar tobacco 131 



