THE HUSBANDRY OF THE CANE. 



obtained per acre of land over large areas and returns of 20,000 Ibs. are not 

 unusual ; on an average, however, the irrigated plantations there yield about 

 12, 000 Ibs. per acre from a crop of plant cane and long and short ratoons. In 

 Java, the average return has reached 11, 000 Ibs. per acre and returns of this 

 magnitude are also known in Peru. A Consular report gives the production in 

 Cuba for the year 1909 as 14,214,946 long tons of cane from 849,000 acres, 

 or 16-7 tons per acre ; with a recovery of 10 per cent, on weight of raw material 

 this would indicate a return of 3700 Ibs. per acre. Elsewhere a return of 

 4000 Ibs. per acre would seem to be also above the average. 



Chemical Selection Of the Cane. By continually selecting for 

 seed beets of high sugar content, the richness of that plant in sugar has been 

 greatly increased ; a similar process is not possible with the cane owing to its 

 asexual process of propagation. The records of more than one experiment 

 station contain accounts of attempts to improve the cane by the selection of 

 cuttings from sweet canes, but the earlier results were inconclusive and con- 

 tradictory. Definite results have been obtained by Kobus 13 in Java, who thus 

 summarizes the results of his experiments : 



"Different stalks of the same sugar cane plant vary widely in sugar 

 percentage even when they are of the same age. Consequently we founded 

 the chemical selection on the analysis of the juice of the whole plant and not 

 on that of single cane stalks. 



" The variability of sugar percentage of various sugar cane varieties is 

 very different. Those grown from cane seeds do not vary so much as the old 

 varieties. 



"The juice of the heavier plants is richer in sugar than that of the 

 lighter ones, and those plants that have the richest juice are the heaviest. 

 Plants grown from cuttings derived from canes rich in sugar are heavier and 

 contain more sugar than those grown from average plants or from plants poor 

 in sugar. 



"When we select the richest canes from the descendants of canes that 

 were already rich in sugar, and also the poorest canes from the descendants of 

 poor canes, and go on in this way for some years, we very soon arrive at a con- 

 siderable improvement in the rich canes (40 per cent, in five years) and a heavy 

 depression in the descendants of the poor ones (60 per cent, in five years). 

 The descendants of cuttings grown from once selected canes remain richer in 

 sugar for at least four generations, and show as an average of forty experiments 

 only a very small decrease. 



" The correlation of a high sugar percentage in the juice and a heavy 

 weight of cane plant simplifies the method of selection in a remarkable way. 

 It is sufficient to select those 20 per cent, that are the heaviest, i.e., the 

 strongest tillered plants of the cane field and plant the cuttings of one-half of 

 these, viz., of those richest in sugar. 



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