THE MANURING OF THE CANE. 



proportions of these ingredients are altered to correspond with, the analysis of 

 the soil. Up to 1000 Ibs. per acre of such a fertilizer may be applied, although 

 600 Ibs. is a more usual dressing. Basic slags are but little, if at all, used. 



In Mauritius and Bourbon large quantities of pen manure were (previous 

 to the extended use of mechanical traction) employed, and the plant canes 

 seldom received any other fertilizer. To ratoon crops a complete mixture, 

 similar to that quoted above as used in Hawaii, is employed but in a much 

 smaller quantity. 



In Louisiana, chiefly owing to its local production, cotton seed meal forms 

 the chief source of nitrogen, and superphosphate forms the source of 

 phosphoric acid. Owing to the abundance of potash in the soil this element 

 is seldom necessary, and its action in retarding maturity is a reason against its 

 use in such a climate. 



In Egypt nitrate of soda is the chief source of readily available nitrogen, 

 applications being made to the young cane after an irrigation. The Nile water 

 used in irrigation brings into the soil a certain quantity of plant food, and the 

 rotations followed also reduce the necessity for such heavy dressings of manure 

 as are used elsewhere. A peculiar manure and of small value, collected from 

 the refuse of old villages and known as 'ruins manure,' is also used by the 

 fellaheen planters, as well as dove dung, to which a quite fictitious value is 

 attached. 



In Barbados and other islands of the British West Indies pen manure 

 forms an important source of plant food. 



Th.6 Ash. of the Cane. In common with other economic plants, the 

 ash of the cane has been subjected to numerous analyses chiefly earned out 

 with the object of determining the demands made on the soil, and of con- 

 structing an agricultural balance sheet. The earliest of these analyses are those 

 due to Stenhouse of canes from British Guiana and the West Indies ; later 

 analyses are those due to Boname 15 in Guadeloupe, to Maxwell 16 in Hawaii, 

 to van Lookeren Campagne, and to Kramers in Java. 



While there is no lack of material, the discussion of these results is beset 

 with enormous difficulty. In the first place a definition is required of the ash 

 of the cane ; that is to say, does the term include the ash of the entire plant, 

 or of the stalk only ? Secondly, the amount and composition of the ash varies 

 with the age of the cane, as is very clearly shown in the analyses due to Rouf 

 and already quoted. Thirdly, there is the effect of climatic variation. 

 Fourthly and finally, there is the question of the reliability of the analyses ; 

 that is to say, under equal conditions can consistent results be obtained? 

 This last point has been gone into very fully by Eckart 9 , who in duplicate 

 experiments in successive seasons failed to find any valuable correspondence 



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