EXERCISES 6 AND 7 

 A SOIL MOISTURE STUDY 



Object. To determine the amount of capillary water in 

 a cultivated and in an uncultivated soil./rn^ 



Explanation. Capillary soil water is the water in the 

 soil that may be used by plants. It is held in the soil as a 

 thin film surrounding the soil particles. It is free to move 

 by the force of capillarity from a moist to a drier portion of 

 the soil. All capillary water evaporates from the soil when 

 it is thoroughly dried in the air. 



Equipment. 1 . Soil auger 3 feet in length. 



2. Six one-quart mason jars. 



3. A piece of oilcloth 18 inches square. 



4. Twelve tin pie pans 6 inches in diameter. 



5. Balances weighing to half a gram. 



Directions. Secure a sample of soil from a garden or 

 field where the ground has been kept cultivated all summer, 

 and another sample from the edge of the garden or edge of 

 the field where the ground has not been cultivated, and where 

 the weeds and grass have been allowed to grow. 



Clear the surface soil of all trash and vegetation, and where 

 the ground has been cultivated, brush back the loosest of the 

 surface soil so that it will not roll down into the auger hole 

 while removing the sample. 



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