THE HUSBANDRY OF THE CANE. 



These reasons are apparently considered to outweigh the loss of nitrogen ; 

 it must not however be forgotten that the burying of the trash puts into the 

 soil large quantities of humus, the importance of which in increasing the 

 water holding capacity of the soil and enabling the canes to pass through a 

 period of drought is very great. 



"Wrapping 9 . This process, the reverse of trashing, seems to be confined 

 to portions of Southern India, where in parts, the dead leaves are wrapped 

 round the stalk ; this process is partly intended as a protection against jackals 

 and partly to diminish rooting and sprouting habits. 



Selective Harvesting. In healthy cane there is a point at which 

 the cane contains a minimum of, or even no, reducing sugars and when it is 

 at its maximum purity ; after this point there is a breaking down of the cane 

 sugar into reducing sugars and the cane is over ripe. In some varieties this 

 reversion is very rapid and it is also influenced by climatic conditions ; it is 

 then a matter of great importance to harvest a field of cane at the time of its 

 maximum purity ; the system under which this selective reaping is pursued is 

 thus described by Prinsen Geerligs 10 : 



" The cane fields are divided into plots which have been planted and 

 manured at the same time and in the same way. After ten months of growth 

 take from each plot 40 normally grown cane stalks, and mark and number them. 

 Every fortnight one cane stalk is cut from each one of the stools and the 

 bundle carried to the laboratory, where the green top end is removed and the 

 canes are measured, weighed, and crushed in a small test mill, after which the 

 juice is analysed. The analytical data from each analysis of the test plot are 

 entered down, so that an increase of sucrose content or purity, or a falling in 

 them, can be detected at once. As soon as the sucrose content or purity cease 

 to augment, the cane of the plot under review has attained its point of 

 maturity, and should be cut in order to prevent deterioration by too long 

 standing in the field." 



In some instances this process is followed in conjunction with a portable 

 travelling field laboratory. 



Ratoonage. The period to which canes are allowed to ratoon varies 

 in different countries ; in Java the great majority of the crop is plant cane only; 

 in Louisiana plant and first ratoons are grown ; in Mauritius it is customary to 

 grow up to third ratoons ; in Cuba, the West Indies and in British Guiana 

 fifth ratoons are not uncommon, and fields can be found that have not been 

 replanted for a generation; in Hawaii canes are seldom allowed to grow 

 beyond second ratoons. The economic limit to which canes can be ratooned 

 can only be determined by those on the spot and familiar with local conditions. 

 Long continued ratoonage has been connected with the prevalence of various 

 forms of root and root stock diseases, as in this case the cane fungus has a con- 

 tinuous habitat. 



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