REVIEW OF THE BOOK 301 



itself is very dry, may it still be of use? At what time of the 

 year is earth-mulch most useful? What relation has surface 

 tillage to weeds? Why do we till? 



Name tools that have a compacting influence on soils. Name 

 some important uses of the compacting of the soil. What is the 

 benefit of rolling the land? What are the disadvantages? What 

 relation has the rolling to germination of seeds? What relation 

 to soil moisture? Does the rolling of the land require much 

 judgment? Why? 



Chapters 5 and 6 



We now consider the enriching of the soil. 

 We have found that the soil is made to be more 

 productive by thorough preparation and by sub- 

 sequent tillage. The plants are enabled to lay 

 hold of the stores of plant -food, and many 

 chemical activities are set up that result in 

 rendering plant -food more available. The plant 

 is given a comfortable and congenial place in 

 which to grow. It thrives. We have found 

 that the physical structure or condition of the 

 soil is of primary importance. When we have 

 secured the best physical condition and have 

 done our best with tillage, we may then think 

 of adding extraneous materials to the soil for 

 the purpose of enriching it. That is, we manure 

 or fertilize the land. Whether this fertilizing 

 pays or not, depends wholly on conditions. The 

 addition of mere plant-food is rarely profitable 

 unless the land is first in condition for the very 

 best growing of the plant. 



