82 DRY FARMING 



disappeared from the soil. But when useless plants or 

 weeds use up the moisture it is a serious economic waste. 

 Recent investigations in soil moisture conservation 

 emphasize the belief that under normal soil conditions 

 weeds are not the secondary but the chief means by 

 which moisture is lost from the soil. They also indicate 

 that tillage for moisture conservation should have as its 

 practical aim"(l) the control of weed growth, and (2) 

 the prevention of soil cracking or soil baking, or the 



Fig. 28. Hauling Alfalfa Grown Under Irrigation at Coaldale, Alberta. 



drying out of the furrow slice. If these aims are fully 

 attained it seems probable that any extra tillage will 

 not result in a sufficiently increased return to pay for 

 the extra work. 



The practices by which the moisture stored in the 

 fallow can be conserved are : 

 1. Early harrowing or packing after plowing in order 



to lessen excessive evaporation from the furrow 



slice, 



