SUGAR CANE SOILS. 



Peruvian Soils. The following account of Peruvian soils is 

 abridged from Sedgwick. 12 



The cane area of Peru lies on the western slope of the Andes, between that 

 range of mountains and the sea, the latitude of the largest district being 7 S. 

 The cultivated areas lie in valleys of a very gentle slope seawards, the 

 drainage notwithstanding being excellent. The depth of the soil is from two- 

 to twenty feet, and it varies in character from a fine sandy loam to silt. 



The soils are of the alkali type, and especially towards the sea contain 1 

 considerable quantities of water-soluble chlorides, sulphates and carbonates. 



The soils are well supplied with plant food, the lime, much of which is 

 present as carbonate, being very high compared with that found in the cane 

 soils of other districts ; the total phosphoric acid and potash are also good ; the 

 nitrogen is very variable, dependent upon the time the soil has been in 

 cultivation, the water supply, the class of weeds, and the amount of flood 

 waters required to cover the fields. 



The humus and organic matter are both higher than would be expected in 

 the soils of an arid district. 



Sedgwick gives thirty analyses of soils from the Cartavio estates, from 

 which the present writer has calculated the averages. The analyses are 

 presumably made by the official American method. 



Maximum. Minimum. 



Mean. 



Insoluble matter 



Alumina 



Lime 



Magnesia 



Potash 



Phospho 



Sulphur: 



Humus . 



. 79-50 . 49-22 .. 63-71 



It is interesting to compare these soils with the equally productive ones of 

 the Hawaiian Islands. These soils are 'acidic,' and contain much more 

 silicates insoluble in hydrochloric acid than do the 'basic' soils of Hawaii, 

 the latter containing much more ferric oxide, and it is as a consequence of 

 this that the availability of the phosphoric acid in the Hawaiian soils is so- 

 much less than in the Peruvian. The high content of the Peruvian soils in 

 lime is, too, a factor which should contribute to their continued fertility. 



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