CHAPTER II. 



THE SOIL. 



The soil is the upper stratum of the earth; the fine- 

 ly divided portion of the surface into which plants 

 send their roots and from which they obtain much of 

 their food. The sub-soil is that which lies beneath 

 the surface soil. Sometimes the word is used to de- 

 scribe the soil lying below the depth which is usually 

 cultivated, and sometimes it means a stratum of soil 

 differing in color, texture or composition from that at 

 the surface. Examination of different soils shows 

 that in some there is much stone or gravel; of others 

 the greater part is sand of differing degrees of fine- 

 ness, still others being mainly made up of matter in 

 very small particles, which we call clay. 



In all soil capable of producing crops traces of de- 

 caying or decayed vegetable matter are found ; in 

 some this matter forms a considerable percentage of 

 the soil. Most soils may be described as either 

 sandy or clayey, according as one or the other of these 

 substances is evidently present in largest percentage. 

 If there is more tham 90 per cent, of either, the 

 surface is spoken of, not as soil, but as sand or 

 clay. 



If there is a nearly equal division the soil is best 

 described as loam — or as sandy loam or clayey loam, 

 if one or the other ingredient is in somewhat larger 

 supply than the other. If stones or gravel are present 

 in large amount, the soil is called stony or gravelly, 

 without regard to whether it is otherwise clay or sand- 

 so 



