PLATE XLII 

 Experimental plots at Missouri Experiment Station: 



Fig. I. — Plot D (right), implowed, no crop, kept clean; plot E (center), unplowed, 

 planted to cowpeas; plot F (left), plowed, planted to cowpeas. 



Fig. 2. — Plot G (right), plowed, no crop, artificially shaded; plot H (left), plowed, 

 no crop, kept clean. 



(448) 



