CHAPTER II 

 THE MAKE-UP OF THE SOIL 



Kinds of Soil. — If we take a small quantity of soil in our 

 hand and look at it carefully, we shall be able to see with the 

 naked eye that it is made up of small particles which look like 

 little stones. These particles are pieces of decayed rock and 

 range in size from those easily seen down to the minute pieces 

 which appear to us as dust. The bulk of the soil, unless it be 

 muck, is made up of these small particles or grains. Besides 

 these small grains of rock there are many particles which 

 seem to be pieces of roots, stems or leaves, and such they are. 

 The rock particles are called the mineral matter of the soil 

 and the pieces of roots, stems and leaves the organic matter. 

 In muck soils the organic matter predominates. 



When the rock particles are large enough to be seen easily 

 they are called sand. The very fine dust-like particles are 

 called silt and clay, the very finest being clay. It takes a mi- 

 croscope to see the finest sand grains and to tell the silt from 

 the clay. When the sand grains are quite prominent the soil 

 is a sandy soil. If no sand particles can be seen and the soil 

 is quite floury when crushed, it is clay. Now, when the sand, 

 silt and clay particles are mixed and not many sand particles 

 can be made out, we have a loam soil. We have various 

 names for soils, such as sandy, light sandy loam, sandy loam, 

 loam, clay loam, heavy clay loam, and clay, all depending 



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