SUGAR CANE. 223 



In Natal 30 tons per acre is considered a good yield, 

 although up to 60 tons have been obtained ; and when the yield 

 yield falls below 20 tons per acre replanting is considered 

 necessary. The first and second ratoon crops are usually the 

 heaviest; after this the yield diminishes rapidly, consequently 

 the fourth to fifth ratoon is the last crop taken. One ton of 

 sugar is obtained from every 8^ to 12| tons of cane. 



The best time of harvesting in Natal is from August to 

 October; i.e., during the drier part of the year, and when 

 the sugar content is highest. 



Keeping Qualities of Cane. — The sugar content 

 decreases rapidly after cutting, consequently no delay should 

 occur in getting the cane to the mills. This is borne out by 

 the result of the following experiment : — " 



Days Cut. 

 12 3 4 



Available sugar (original 



sample 100) 100 97-3 92-0 78-6 67-9 



Irrigation. — The crop responds very readily to irrigation 

 and in many parts of the world it is common practice to give 

 60 inches of water in this way. In Natal however, all cane 

 is grown without in-igation. In parts of Zululand irrigation 

 might be possible and, consequently, an annual crop might be 

 produced of varieties in some ways superior to Uba. 



Composition. — Uba (Pearson). 



Total solids in juice percentage 

 Sucrose , , 



Glucose , , 



Non-sugars 

 Glucose ratio ,, 



Purity , , 



Percentage juice in cane 

 Percentage fibre in cane 



The above analyses show a large percentage of fibre in the 

 cane, but indicate no inferiority in the juice; in fact, the 

 quality of the juice so far as disclosed by analysis, would not 

 be readily surpassed anywhere. 



As a forage plant, sugar cane must be looked upon as 

 being very deficient in nitrogen, but high in carbo-hydrates; 



