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CHAPTER X 



Yields of 15 to 30 bushels (4 to 8 bags) per acre are con- 

 sidered good. 



Composition : Showing Percentage of Digestible 

 Nutrients. 



General. — While used for much the same purposes in 

 rotations as cowpeas, soy beans should be considered more from 

 their value as seed, while cowpeas, being relatively smaller 

 yielders of seed, are of greater importance from a point of view 

 of hay and green-manuring. Soy beans are, however, more 

 resistant to frost and drought and will furnish good crops even 

 on thin acid soils. 



In South Africa failures are often reported on land on 

 which soy beans have not been previously grown, and while 

 this is no doubt frequently due to imported seed which has 

 remained on seedsmen's hands for a number of years and is 

 consequently of low vitality, it is not unlikely that these 

 failures may be due to an absence of soy bean nodular bacteria. 

 Should the latter be the case, a small quantity of soil, on which 

 soy beans have grown well, might be broadcasted and harrowed 

 in at the time of seeding. 



The high prices obtained for soy bean seed will attract 

 greater attention in South Africa as farming becomes more in- 

 tensive. Only yellow seeded varieties are shipped from Man- 

 churia to Europe, and as European buyers are accustomed to 

 purchasing these, it will probably pay to grow varieties with 

 yellow seeds. 



In storage the seed is apt to overheat, but this can be easily 

 obviated by providing good ventilation. 



Uses. — The crop may be grown for hay, silage, green- 

 manuring or for seed. The seed may be used for human con- 

 sumption. Soy bean cake, the residue after the extraction of 



