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THE HUSBANDRY OF THE CANE.obtained per acre of land over large areas and returns of 20,000 lbs. are notunusual; on an average, however, the irrigated plantations there yield about12,000 lbs. per acre from a crop of plant cane and long and short ratoons. InJava, the average return has reached 11,000 lbs. per acre and returns of thismagnitude are also known in Peru. A Consular report gives the production inCuba 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 materialthis would indicate a return of 3700 lbs. per acre. Elsewhere a return of4000 lbs. per acre would seem to be also above the average.Chemical Selection of the Cane.—By continually selecting forseed beets of high sugar content, the richness of that plant in sugar has beengreatly increased; a similar process is not possible with the cane owing to itsasexual process of propagation. The records of more than one experimentstation contain accounts of attempts to improve the cane by the selection ofcuttings from sweet canes, but the earlier results were inconclusive and contradictory.Definite results have been obtained by Kobus 13 in Java, who thussummarizes the results of his experiments :—"Different stalks of the same sugar cane plant vary widely in sugarpercentage even when they are of the same age. Consequently we foundedthe chemical selection on the analysis of the juice of the whole plant and noton that of single cane stalks." The variability of sugar percentage of various sugar cane varieties isvery different. Those grown from cane seeds do not vary so much as the oldvarieties." The juice of the heavier plants is richer in sugar than that of thelighter ones, and those plants that have the richest juice are the heaviest.Plants grown from cuttings derived from canes rich in sugar are heavier andcontain more sugar than those grown from average plants or from plants poorin sugar." When we select the richest canes from the descendants of canes thatwere already rich in sugar, and also the poorest canes from the descendants ofpoor canes, and go on in this way for some years, we very soon arrive at a considerableimprovement in the rich canes (40 per cent. in five years) and a heavydepression in the descendants of the poor ones (60 per cent. in five years).The descendants of cuttings grown from once selected canes remain richer insugar for at least four generations, and show as an average of forty experimentsonly a very small decrease."The correlation of a high sugar percentage in the juice and a heavyweight 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., thestrongest tillered plants of the cane field and plant the cuttings of one-half ofthese, viz., of those richest in sugar.125