SOIL WATER 



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adobe soil of the West is of this character. If the soil is 

 nearly pure clay, it is useless for farming. If sufficient 

 sand or humus can be added, clay soils become valuable, 

 since they usually contain the elements needed by plants. 

 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-pro- 

 ducing states of our 

 country. It holds 

 water well, contains 

 an abundance of 

 plant food, and is 

 easily cultivated. 

 Between these three 

 types sand, silt, 

 and clay there are 

 all grades of soils, 

 presenting problems 

 of various degrees. 

 The problem of the 

 farmer, however, is 

 to maintain a soil 

 which holds water 

 but is well drained, 



which contains the elements plants need, and which is 

 mellow enough to be well aired and to let the plant roots 

 grow. 



Soil Water. Although many soils contain everything 

 needful for the production of agricultural plants, yet the 



ADOBE SOIL 



A heavy clay soil, very fertile but hard to 

 cultivate. 



