WHAT IS SOIL? 



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full size, then we can at once see the real reason for know- 

 ing some science. How otherwise could we improve the 

 yield in our gardens? If we do not know about the com- 

 position of soil, the principles underlying crop rotation, the 

 reasons for the use of certain fertilizers, or the different 

 ways of handling soil, then it is not likely that we shall get 

 as much out of our home garden as the boy or girl who 



Cultivating the home garden. 



does have this knowledge. The following pages will help 

 us to apply our knowledge of science to the project of mak- 

 ing our home garden more productive. 



What is soil ? We have already learned that soil is 

 composed largely of inorganic material, as powdered rock, 

 and that it usually contains organic material which has 

 come from the decay of plants and animals. Most of us 

 say that dark soil is rich, meaning that it has a great 

 deal of organic material in it. Soils, as we know, may be 



