68 



The Bulletin. 



Table XXI— SHOWING PERCENTAGE COMPOSITION AND COMPARA- 

 TIVE FEEDING VALUE OF COWPEA-VINE HAY AND WHEAT BRAN. 



The table below shows the comparative fertilizing and manurial 

 value of one ton each pea-vine hay and wheat bran : 



Table XXII— SHOWING NUMBER OF POUNDS OF PHOSPHORIC ACID, 

 POTASH, AND NITROGEN IN ONE TON PEA-VINE HAY AND WHEAT 

 BRAN AND VALUES PER TON. 



A study of the results of the variety tests already presented will 

 show the ones which are specially desirable for hay, among them 

 being the following: 



Iron, 



Unknown, 



Clay, 



Brown Coffee, 



Whippoorwill, 



Red Crowder, 



IsTew Era. 



SOIL IMPROVEMENT. 



The co^vpea is likely grown more largely for soil improvement than 

 for all other purposes combined, and if it has a use gTcater than for 

 soil improvement, it is second only to its feeding value, which has 

 already been seen to be high. 



Nitrogen is the most costly constituent in fertilizers. The cowpea 

 is able to get its supply of this constituent from the inexhaustible 

 supply of nitrogen in the air. This nitrogen is taken from the air 

 circulating through the soil spaces by the very minute, microscopic 

 organisms living on and in the nodules, warts, or enlargements on the 

 roots of the cowpea plant. These nodules are the home of the bacte- 

 ria and are shown in the cut on another page. Com, cotton and the 



