COWPEAS, OR KAFFIR BEANS. 157 



Cowpeas make excellent feed for all live stock. The hay 

 is said to equal wheat bran for producing milk. 



KoTATiONS. — Being a quick growing summer crop, it is 

 well adapted as a green-manuring for forage crop with cereals 

 as a winter crop. If used in this way it should be ploughed 

 down as early as possible to ensure fairly complete decomposi- 

 tion and to prevent too open a condition of the soil for thii 

 cereals. The following results were obtained for wheat at 

 Potchefstroom Experimental Farm, viz. : — • 



1916. 1917. 1918 



Cowpeas cut for forage, 



followed by wheat ... 1,400 lbs. 1,380 lbs. 1,240 lbs. 



Maize followed by wheat 800 lbs. 520 lbs. 540 lbs. 



In the above experiment, even after the above-ground parts 



of the plant were removed, the residual effect of cowpeas on 



winter cereals was clearly shown. 



Diseases and Pests. 



Cowpea Wilt (Fusarium spp.).— These organisms attack 

 the roots. Wilt resistant varieties, e.g., Iron, should be used, 

 or a change of crop is advised. 



Koot-Knot. — This is caused by a nematode {Heterodera 

 radicicola). The iron variety is said to be immune, and, if 

 unobtainable, a wide rotation should be adopted. 



Weevils {Pachymerus chinensis and quadrimaculatus) . — 

 These lay their eggs on the pods in the field or on the seed in 

 storage. As the life cycle is only 18 to 30 days, the damage 

 increases with storage unless steps are taken to ensure their 

 destruction. If the seed is placed in containers, e.g., galvan- 

 ised bins or tanks, they may be fumigated with carbon- 

 bisulphide, care being taken to aerate the seed soon afterwards, 

 otherwise its vitality may be impaired. 



The Bean Ply [Agromyzia pJiaseolii) may be serious, par- 

 ticularly in late plantings. Eggs are laid on the stem near the 

 surface of the ground, and on hatching the larvae invade the 

 tissue and eventually pupate in the stem, causing the plant to 

 die prematurely, or to be stunted. Early planting is advocated. 



REFERENCES: 

 ^ " Agricultural Values of Cowpeas and Their Immediately Related 

 Species." — Piper. 



2 " Flora Capen^is." — Harvey and Saunders. 



3 Ohio Bulletin No. 237. 



