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PRACTICE 31 



Determination of the Effect of Cultivation and Mulches 

 upon Temperature and Moisture. 



A number of students may work at this experiment, each one be- 

 ing assigned a definite problem. 



Select a level area of four or five square rods and remove any veg- 

 etable matter, such as weeds, etc. Break up with plow or spade all 

 but one square rod. Place a mulch of straw or leaves several inches 

 deep upon a half square rod of both the plowed and the unplowed. 

 Roll a portion of the plowed area. 



Determine temperature at one, two and four inches in depth 

 on days when the sun is shining. Read the thermometer every two 

 hours. 



Determine moisture to a depth of forty inches once each week for 

 at least four weeks. 



