SOY BEANS. 159 



cowpea seed 1 :3"4. Soy beans have a fat content of 14' 6 per 

 cent., as compared with 1 per cent, in the cowpeas. With few- 

 exceptions they show no tendency to vine, while all cowpeas 

 are viney to a greater or less degree. Soy beans are heavier 

 seed yielders. Unlike that of the cowpea, its seed is immune 

 to the attacks of weevil. 



Varieties. — All the known varieties belong to one species, 

 Soja max. Those grown in South Africa have all been im- 

 ported in comparatively recent years. The best known are : — 

 Mammoth, Ito San, Hollybrook and Green. 



Ito San. — Early, erect, purple flowers, seeds yellow with 

 a brown spot round the hilum, slender stems, good for hay, 

 matures in about 100 days. 



Mammoth. — Tall, late variety, bushy, white flowers, grey 

 pubescence and yellow seeds. Too late for the highveld. 



Hollybrook. — Fifteen to twenty days earlier than Mam- 

 moth, seeds yellow, pubescence grey, plants not so tall as 

 Mammoth. 



Green. — Medium early, pods burst and shatter seeds very 

 early, seeds green, ellipsoidal, plants comjiaratively short. 



Cultural ]Methoi)s. — Like cowpeas, about twenty to 

 sixty pounds are required , the amount depending on the variety 

 and whether drilled or broadcasted. The smaller varieties like 

 Ito San should be drilled 24 inches apart, while the large, vigor- 

 ous growing varieties like Mammoth should be planted 36 inches 

 apart. They should not be planted deeper than 1 to 2 inches. 

 Their growth during cool weather is very tardy, consequently 

 while they can be sown earlier than cowpeas, being more frost 

 resistant, there is very little advantage in doing so. 



When cut for fodder they should be reaped when the pods 

 are quite green, but well formed. For this purpose they must 

 be harvested early, as the stems become very woody and the 

 protein decreases as maturity advances. The yield of hay 

 varies from 1 to 4 tons. Flarvesting is easier than in the case 

 of cowpeas, because the plants do not intertwine. 



Judgment is required in harvesting for seed on account of 

 the shattering habit of most varieties when fully mature. For 

 this reason tiie crop when harvested for seed should be moved 

 as little as possible. Since most of the leaves have fallen by 

 the time the seeds are matured, very little preliminary drying 

 is necessary before stacking. 



They are threshed by adjusting the ordinary grain 

 thresher, by stock tramping, or by the use of the flail. 



