SOILS. 5 



Eolian soils are tjiose that have been accumulated by the 

 wind. 



Alluvial soils are those that have been carried and deposited 

 by water. 



Drift soils are those that have been brought to their present 

 location by the action of glaciers, as the drift clay in the northern 

 part of the United States which is the result of the movement of 

 the continental glaciers as they crept southward in prehistoric 

 times. 



These different- kinds of soils and the rocks from whence 

 they came and the rocks that lie immediately below are stored 

 with the essential elements of soil fertility. 



The soil, and the rocks, from which it is formed have been 

 likened to a great storage battery. But fortunately for man this 

 great mineral wealth is not immediately available for use. This 

 plant food was stored up ages ago in such a manner that it is only 

 given up in small quantities, only as each succeeding annual 

 growth of vegetation has needed it, and even this is not always 

 available without the application of some of the discoveries that 

 are due to agricultural science. 



Feldspar, a constituent of granite, contains nearly 14 per cent, 

 potassium, or three times as much as wood ashes, but there is 

 no known method as yet that has made it a source of great help 

 to' agriculture. 



Phosphorus is distributed universally through the soil usually 

 in combinations with iron or lime, but it has to receive some form 

 of treatment to liberate it for use in agriculture. 



Muck or peat found in swamp land is rich in nitrogen, but it 

 is the result of vegetation that grew under such conditions that 

 it resists decay, and the nitrogen is held in firm combination such 

 as potassium in feldspar, or phosphorus in the rocks of Tennessee 

 and other states in the south and west. 



Therefore a soil may be rich in quantity of, and yet poor in 

 the availability of plant food. 



Soil Analysis. 



"Chemical analysis is not a sufficient guide to the fertilization of 

 the soil." Dr. Thome. 



