748 MAIZE 



chap, about equal food value for amount of dry matter consumed, but 



XV. 



that ordinarily there is less waste in the consumption of silage, 

 thus adding to the total returns per acre" {Henry, i). 



The following definition of silage is given by Russell (i) : — 



"When the green parts of living plants are cut up and 

 packed in a loosely covered vessel allowing entrance of air, 

 mould soon makes its appearance and decomposition begins ; 

 the mass becomes alkaline and is ultimately converted into 

 black humic bodies quite unfit for cattle food. But if air is 

 excluded the change is fundamentally different; no mould 

 develops, the temperature rises, the mass takes on a greenish- 

 brown colour and characteristic odour, it becomes acid and for 

 a long period is suitable for cattle food. The former is a 

 putrefactive change, the latter gives rise to silage. The general 

 chemical changes known to take place during ensilage are the 

 conversion of sugar and similar bodies into carbon dioxide and 

 water, the production of volatile acetic and butyric acids and 

 of non-volatile lactic acid and the conversion of protein into 

 non-protein material." 



The modern meaning of the word silage is green, succulent 

 food-stuff which has been preserved in a silo. A silo is a pit 

 or erection in which such food-stuff is preserved. The process 

 of preserving the material is known as ensiling. The process 

 of ensiling food-stuffs is a very ancient one (" 743) but was 

 originally applied mainly to grain ; it was practised by the 

 South African native to preserve his kaffir corn, probably long 

 before the advent of the white man. 



The relative weight of crop which can be obtained from an 

 acre of cultivated land is one of the main considerations in 

 deciding between the relative merits of the various silage crops. 



It is false economy to make silage of any crop which can 

 be preserved in the ordinary process of haymaking, and in the 

 climate of South Africa, with its dry atmosphere and abun- 

 dance of sunshine, the making of silage from grass, and such 

 crops as teff or manna, is not recommended. There is a mini- 

 mum loss in the feeding value of such crops when made into 

 hay, but they do not make such good silage. With bulky, 

 succulent crops like maize, kaffir corn, sorghum, and teosinte, 

 which do not dry readily, ensiling is often the best method 

 of preservation, especially at the time of vear when thev 



