196 ECONOMIC PLANTS 



results as to yield may be obtained by this method 

 if the land is reasonably free of weeds. Much of the 

 success in raising corn, so far as man can affect it, 

 depends upon keeping the weeds down and the surface 

 of the ground well tilled. Early cultivations may be 



FIG. 101. Two-row Cultivator. 



deep, but the later ones should be quite shallow, so as 

 not to disturb the roots. 



Suggestive Experiment. To determine the best depth at which 

 to plant corn, fill a glass jar with garden soil to a height of 5 or 6 

 inches from the top, put in a kernel of corn flat against the side of the jar; 

 put in another inch of soil, then another kernel of corn as before, and con- 

 tinue this until the jar is full, arranging the kernels spirally as shown in 

 Figure 98. Moisten the soil, cover the bottle up to the neck with black 

 paper or cloth and set it in a warm place. By taking off the covering 

 and examining the seeds daily you can determine the best depth at which 

 to plant corn. 



