SUGAR-CANE 



SUGAR-CANE 



601 



of differing degrees of earliness, by varying the 

 planting season, by taking advantage of low land 

 and high land and other natural conditions, it is 

 possible to extend the crushing season so as to get 

 a maximum result from the capital invested in the 

 mill and from the laboring force of the plantation. 

 As we shall see later (page 602), the time of ripen- 

 ing, i. e., the distribution of the sugar in time, as 

 well as the distribution of the sugar in the stalk, 

 have much to do with the selection and preparation 

 of seed-cane. 



The kind of sugar present in the cane, as well 

 as the amount of it, determines its industrial 

 value. The property that makes the saccharine 

 substance of the greatest industrial value at the 

 present time, is that of its being extractable 

 by the known processes of crushing, concentra- 

 tion and crystaillization. Preeminent aniong the 

 extractable saccharine substances of this nature 

 is sucrose. This crystallises out as "cane-sugar," 

 and is the same substance as that obtained from 

 sugar-beets and a variety of other plants. In fact, 

 from a practical point of view, at the present time, 

 we may say that the amount of extractable sucrose 

 determines the value of the cane more than any 

 other factor except that of ability of the cane 

 economically to reproduce itself with this sugar- 

 content unimpaired. We must not forget in this 

 connection, however, that the ease with which the 

 sugar can be extracted is also an important factor. 

 The presence of saccharine matters other than 

 sucrose is deprecated by planters because their pres- 

 ence generally indicates a lowering of the sucrose, 

 the energy of the plant having been consumed in 

 producing sugar or saccharine matter that is not 

 extractable, in place of a certain amount of sucrose 

 that might have been produced. The extractability 

 of the sucrose depends to a certain extent on the 

 absence of certain organic substances which tend 

 to cause the sucrose so to change its molecular form 

 as to become unextractable or of less value. To a 

 large extent, these difficulties are surmounted by 

 the application of hydrate of lime to the juice as 

 soon as possible after it is removed from the cane. 



For practical purposes it is often convenient to 

 consider the cane as composed of juice and fiber, 

 leaving out of mind the composition of these two 

 component parts. Proceeding on these lines, we 

 may say that the amount of juice in a given volume 

 of cane will be the greater, the less the amount of 

 fiber. The fiber of the cane-stalk exists in the form 

 of strands or fibrovascular bundles distributed in 

 the stalks as follows: (1) A part in the form of 

 fine parallel fibers in the internodes, and (2) a part 

 woven together at the nodes. From this it follows 

 that a cane having numerous nodes close together, 

 so that the internodes are short, contains the great- 

 est amount of fiber, because it is at the nodes or 

 joints that the fiber is most compact, and the sugar- 

 bearing tissue is at its minimum. Cane with long 

 joints is therefore generally looked on with favor by 

 planters as being likely, other things equal, to con- 

 tain the greatest amount of sucrose. It frequently 

 happens when the growth of the cane is hindered 

 by cold weather or by drought, that the slower 



growth is marked by an abundance of joints or 

 nodes near together. Such cane is usually charac- 

 terized by a lower percentage of sugar. The prac- 

 tical application of this fact is illustrated by all 

 those methods of culture that tend to keep the cane 

 growing uniformly, as, for example, in the appli- 

 cation of irrigation water to piece out the irregu- 

 larity of the natural rainfall, and the application 

 of artificial manures to stimulate the growth dur- 

 ing periods when the growth would naturally be 

 slow. 



In general it/ may be said that the varieties 

 that are lowest in fiber are such as give the 

 highest . yield of sucrose and are the varieties 

 preferred where the conditions are suitable for 

 them. They are, however, what may be termed 



Fig. 827. To show action of a plow employed to burst up the 

 big latoon stools of sugar-cane. Location of root disease 

 is indicated by tha curved line. This plow cuts the stool 

 into six pieces, as shown by the lines. The more obliquely 

 the disks are set the more squarely the stubble is cut 

 across. The more squarely it is cut the quicker it dries, 

 thus creating conditions unfavorable to root disease. 

 (Redrawn from Bulletin No. 5, Division of Fatho].ogy, 

 Hawaiian Sugar Planters' Association.) 



delicate' canes, and it frequently happens that 

 through the attacks of diseases they are made 

 unproductive, so that in time they have often been 

 replaced by other varieties with more fiber, but 

 more resistant to disease. Examples of this are 

 the Bourbon cane of the West Indies, the Lahaina 

 cane of Hawaii, and the Rappoe cane of Australia. 

 When, however, these canes meet with the right 

 conditions, they are still preferred to any others. 

 With strong sunlight, fertile soils, high tempera- 

 ture and uniform conditions, all of which favor 

 the growth of the cane and are not particularly 

 favorable to fungous pests, these canes are the 

 most profitable. Good cane, as it comes to the 

 mill in most tropical countries, contains up to and 

 sometimes even beyond 20 per cent of sucrose, 

 averaging 15 to 18 per cent. The extracted juice 

 contains, under favorable conditions, 17 to 18 per 

 cent of sugar. 



It will have been noted that the amount of 

 extractable sugar depends on its own nature and 

 that of the collateral products, and not altogether 

 on the structure of the stalk. Modern mills are so 

 powerful and modern methods so efiicient that the 



