CANE SUGAR. 



Java. Repeated experiments in Java 8 have shown that under 

 conditions there prevailing, manuring with readily available nitrogen alone 

 leads to the best financial results. The flooding of the fields during the 

 period that they are under rice brings down in suspension finely divided soil, 

 which affords a supply of potash and phosphates. In addition, the system of 

 land tenure there prevailing does not justify the cane planter in adopting 

 measures towards the permanent amelioration of the soil. 



Effect of Manuring on the Composition of the Cane. 



There is a wide-spread belief that heavy manuring adversely affects the quality 

 of the juice of the cane and under certain conditions this may be correct ; 

 thus in a district such as Demerara, where a short period of growth obtains, a 

 late manuring results in an impure juice. Possibly in such a case not only is 

 the maturity of the crop delayed, but a second growth of young cane is 

 stimulated and the comparison may become one of mature and of immature cane. 

 Again with heavy manuring, there is a consequent increase in the size of the 

 crop with less access of direct sunshine, and a delayed ripening is the result. 



That judicious heavy manuring has no harmful effect is shown from the 

 results regularly obtained in Hawaii ; nowhere is a sweeter and purer juice 

 obtained, and nowhere is the manuring more intense. Here, however, owing 

 to climatic conditions peculiarly favourable, a great part of the harvest 

 consists of fully matured cane cut at the period of maximum sweetness. 



Actual experiments on this point lead to somewhat contradictory results. 

 Thus Eckart 9 found in Hawaii with unmanured cane a sucrose content in the 

 juice of 18-26 and purity of 90*69, manured canes affording a juice containing 

 from 16'40 per cent, to 17'85 per cent, sucrose, and of purity 89-16 to 90-60. 

 Conversely, however, the same authority has supplied me with data of an 

 experiment where, in three instances, an application of 1200 Ibs. of high grade 

 mixed fertilizer and 300 Ibs. of nitrate per acre not only enormously increased 

 the yield but gave a sweeter and purer juice. 



Of the specific effect of manures, many ideas, supported or not by experi- 

 ment, may be met with. Lime is credited with producing a sweet and pure 

 juice in the "West Indian adage, " The more lime in the field the less in the 

 factory," and this idea is reflected in the quotations at the beginning of 

 Chapter V. 



Phosphates are also believed to affect beneficially the sugar content of the 

 cane, and potash is reputed to have the reverse effect ; Harrison's experiments 

 already quoted fail however to countenance this idea. 



There is a certain amount of evidence that canes heavily manured with 

 readily available nitrogen are more susceptible to fungus attacks than are 

 others ; this may be due to the production of a soft rinded cane due to rapid 



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