EXERCISE 12 

 SOIL DRAINAGE 



Object. To study the effect of standing water in the 

 soil upon the growth of plants. 



Explanation. A plant, to develop properly, must be 

 grown in a soil supplied with both air and water in proper 

 proportions. When the soil contains too much water, all 

 the spaces between the soil particles are filled, and there is 

 no room for air. A plant growing in a soil in this condition 

 will not thrive because its roots will not receive sufficient 

 air. The water must be removed from a saturated soil so 

 that air can enter before crops will grow well. This can 

 best be accomplished by means of tile drainage. 



Equipment. 1. Two chemical thermometers. 



2. Two one-gallon flower pots. 



3. A pound of paraffin. 



4. A two-quart saucepan in which to melt paraffin. 



5. A one-foot rule. 



6. Graduated cylinder, 100 c.c. 



7. A few grains of corn. 



8. Loam soil, and a small amount of gravel. 

 Directions. Melt the paraffin and dip one flower pot 



so that it is covered with a thin coating of paraffin. 

 Allow the paraffin to cool and solidify slightly. While 

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