INDEX 



2 55 



Plows, 4. 



Plumule, 78. 



Pollen, 130. 



Pollination, 131, 132, 135. 



cross, 132, 133, 135. 



of wild goose plum, 134. 

 Potash, 199. 



in fertilizers, 199. 



in soils, 149. 



sources of, 171. 

 Potassium, in plants, 66, 67. 



in soils, 68. 

 Potato, 6. 



soils, 28, 29, 161. 

 Potato, sweet, 



roots of, 13. 



soils, 28, 160. 

 Properties of a fertile soil, 



141. 

 Pruning, 137. 



Quitch grass, 121. 

 underground stem of, 121. 



Radicle, 78. 



Radish, shrunken root of, 



10. 



Ragweed, 5. 



Rain, work of in making 

 soils, 33. 



on clay soils, 41. 



on sandy soils, 41. 

 Rake, 101. 

 Rakes, 4. 



Raking and soil water, 158. 

 Red spider, 117. 

 Rhubarb soil, 28. 

 Ridging the soil, 98, 158, 169. 

 Rock salt, 31. 

 Rollers, 107. 

 Rolling, 101, 106, 158. 



autumn-sown grain, 106. 



light soils, 106. 



reason for, 106. 



spring-sown grain, 106. 

 Rolling cutter harrows, 102. 



Root, 8. 



how it takes moisture, 18. 

 most important part of 



plant, 7. 



Root hairs, 17, 18. 

 Roots, 



absorb water, 9, n, 17. 

 absorb plant food, 10, n. 

 alfalfa, 13. 

 and fertilizers, 15. 

 growth of in length, 16. 

 conditions necessary for 



growth of, 8, 20, 141, 



220. 



corn, 13. 

 cowpea, 12. 



depth of growth of, 12. 

 extent of growth of, 12. 

 habit of growth of, 11, 15. 

 hold plant in place, 9, u, 



15, 16. 

 important lessons from, 



13,. 15- 



location of, 12, 13. 

 need firm soil, 20, 22, 23. 

 need mellow soil, 20, 22, 



23- 



need moist soil, 20, 22, 23. 

 need plant food in soil, 20, 



22, 23. 



need warm soil, 20, 22, 23. 

 need air in soil, 21, 22, 23. 

 produce new plants, 10,11. 

 rapidity of growth of, 15. 

 soy-bean, 12. 

 store food, 10, II. 

 sweet potato, 13. 

 tree, 13. 



uses of, 9, 10, n, 15. 

 work of, 9, 10, 15. 

 Rotation of crops, 219. 

 benefits from, 230. 

 conditions which modify, 



232. 



effect upon fertility, 224. 

 examples of, 234. 

 general rules for, 233. 



