AGRICULTURAL SOILS 



95 



A soil having grains about midway in size between sand 

 and clay is called a silt. This is usually a most fertile 

 soil. It is the soil of the 

 western prairies and the 

 great grain-producing 

 states of our country. 

 It holds water well, con- 

 tains an abundance of 

 plant food, and is easily 

 cultivated. Between 

 these three types sand, 

 silt and clay there are 

 all grades of soils pre- 



senting problems of vari- THE CRACKING OF ADOBE SOIL WHEN 

 ous degrees. The prob- DRY - 



lem of the farmer, however, is to maintain a soil which 

 holds water but is well drained, which contains the ele- 



PRAIRIE SCENE. 

 Showing modern methods of harvesting the crops from the fertile silt soil. 



ments plants need, and which is mellow enough to be well 

 aired and to let the plant roots grow. 



