50 PRODUCTIVE FARMING 



CHAPTER V. 

 KINDS OF SOILS— THEIR CHARACTERISTICS. 



Soils used in the production of crops are of many kinds. 

 Some of these differ widely from each other in their physical 

 nature and in their abihty to produce good return to the 

 owner. It is the purpose of this chapter to point out the 

 characteristics of the most important types of soil. 



Kinds of Soil. — Soil may be divided into four natural 

 classes — sandy, loamy, clayey, and peaty — according to the 

 proportion of sand, clay, and vegetable matter which it con- 

 tains. Between these groups or classes we may have very 

 many others, depending on the combinations of these types 

 and the sizes of the soil particles. 



A loam is a soil intermediate between sand and clay. 



A marly soil is a combination of clay and fine lime mate- 

 rial. 



Silt is a soil whose particles are slightly larger than clay 

 particles but finer than sand. 



We should mention also limestone soils. These result from 

 the crumbling of limestone (Fig. 30). 



Sandy Soil. — Sand is formed from sandstone. It does 

 not produce large crops, for it is poor in plant-food and 

 moisture. A soil made of sand only would need to be changed 

 a great deal to be of any use in farming, as it would produce 

 no crops in its natural condition. Soil with much sand in it 

 is light and open and allows the entrance of air, and it can 

 absorb and hold little moisture. Sandy soil is so loosely 

 held together that water and air pass through it readily. 

 Crops on such land become parched if the weather is hot and 

 dry. 



This type of soil dries quickly even when the season 

 is wet. Then large crops may be grown better on sandy soil 



