i 3 6 CHAPTER VIII 



by Harrison 11 and by Prinsen Geerligs 12 have shown that this belief is 

 unfounded. After the cane has arrowed no further formation of sugar takes 

 place, but an elaboration of that already formed obtains with an increase in 

 the cane sugar content and in the purity ; eventually, however, the cane 

 dies down and then a breaking down of the cane sugar occurs. The time 

 to which cane can be left standing after arrowing is very variable and is 

 dependent on variety and climate. In the Hawaiian Islands cane may re- 

 main as long as six months after arrowing, before deterioration sets in. 



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

 contains a minimum of, or even no, reducing sugars and where 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 13 : 



" 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 ceases to augment, the cane of the plot under review 

 has attained its point of maturity, and should be cut in order to prevent deteriora- 

 tion by too long standing in the field." 



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

 travelling field laboratory. 



Period of Ratoonage. The number of crops that may be taken off an 

 area with one planting varies very greatly as between different districts, 

 and has an important bearing on the economy of a plantation. Generally, 

 the more crops of reasonable magnitude that can be obtained from one 

 planting, the greater is the benefit to the plantation, and indeed in some 

 localities the plant crop results in a loss, the profits being entirely due to the 

 ratoon crops. It is often stated that the yield per acre progressively falls 

 with each crop of ratoons, and, although over long periods there is a gradual 

 falling off, very often it will be found that first and second ratoons give a 

 harvest equal to that afforded by the plant crop. The period of profitable 

 ratoonage depends both on soil and variety. As long ago as the very early 

 years of the eighteenth century Rumpf 14 observed and regretted that canes 

 in the East Indies did not afford the same long period of ratoonage as was 

 given in the New World. Similarly Humboldt 15 has recorded that at the 

 introduction of the Otaheite cane to Cuba the planters were fearful that it 

 would not be found to have good ratooning qualities. It has also been 

 observed that many of the newer seedling canes are bad ratooners, and some 

 even degenerate into reed-like stalks after a few years' continuous growth. 



Practice in different countries varies very greatly. In Java the crop 

 is almost entirely " plant cane." This follows on the system of land tenure 

 there, which does not allow Europeans to rent the same, area of saw ah land 

 for more than eighteen consecutive months. In Louisiana it is customary 



