172 J ouryial of Agricultural Research voi. v,no.4 



to the dry and cold soil increased with temperature and with moisture 

 content. But when the moist column of soil was maintained at 0° and 

 the dry column of soil at 20° and 40° C. for the same number of hours 

 there was very little, if any, movement of water from the former to the 

 latter. 



These results have led to the conclusion that temperature has a very 

 marked influence on the conservation of moisture by mulches. 



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(8) LagergrEn, S. 



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