SUGAR CANE SOILS. 



Hawaiian Soils. The soils of the Hawaiian Archipelago have been 

 examined in great detail by Maxwell 6 and by Eckart and to a less extent by 

 Crawley, by Shorey, and by Hilgard; 7 in view of the exceptionally high 

 returns obtained in this district the study of these soils is of especial interest. 



The soils of the Hawaiian Islands have been formed by the decomposition 

 of black basaltic lavas containing very large quantities of iron and lime, but 

 much smaller quantities of potash ; these basalts also contain considerable 

 quantities of phosphates in the form of apatite. 



Maxwell classifies the Hawaiian soils as follows : 



A. GEOLOGICAL FORMATION. 



1 . Dark Red Soils. Soils formed by the simple weathering of normal lavas, 

 in climatic conditions of great heat and dryness. 



2. Yellow and Light Red Soils. Soils derived from lavas that underwent 

 great alteration, under the action of steam and sulphurous vapours, at the time of, 

 or after, emission from the craters. 



3. Sedimentary Soils. Soils derived from the decomposition of lavas at 

 higher altitude?, and removal and deposition by rainfall at lower levels. 



B. CLIMATIC CLASSIFICATION. 



1. Upland Soils. Soils formed under lower temperatures and greater rainfall, 

 and distinguished by a large content of organic matter and nitrogen, and by a low 

 content of the elements of plant food in an available state ; these elements having 

 been removed by rainfall. 



2. Lowland Soils. Soils formed under a high temperature and less rainfall, 

 and characterized by a lower content of organic matter and nitrogen, and by a 

 higher content of the elements of plant food in a state of immediate availability ; 

 which is due in part to the receipt of some soluble constituents from the upper 

 lands, and to a smaller rainfall over the lower levels. 



It is on the dark red soils and on the sedimentary soils that the high 

 yields of cane in this district are produced. These sedimentary soils are often 

 of great depth, reaching to as much as 30 feet, and form the soil of the most 

 productive areas in the group of islands. 



The colour of the yellow soils is due to ferrous salts, and it is to the 

 presence of these bodies that Maxwell attributes the smaller productiveness of 

 these soils. (The yellow colour of the clay known in Dernerara as * Yellow 

 Mary,' the obnoxious nature of which is well known, is also due to ferrous 

 salts.) 



The soils of Hawaii are all ' basic ' in character, and are consequently 

 marked by a low proportion of silica, in contradistinction to soils as clays of 

 an ' acidic ' nature which consist very largely of silica. The quantity of iron 

 in Hawaiian soils is very remarkable, the percentage of ferric oxide reaching 

 to as much as 30 per cent. 



As a general rule the soils are * light ' and easily worked, and in 

 every way fitted for the production of enormous crops. The following figures 



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