PINEAPPLE cn/miE IN S<>rTH AFRICA 



to develop the normal amount of colouring ; it is better known 

 as " Chlorophyll ". The leaves are sickly green or yellow or 

 veined with white, or in very bad cases, absolutely white. This 

 does not apply, of course, to plants which are normally varie- 

 gated either with white or yellow, as, for instance, the Golden 

 leaved privet, or the silver or golden leaved Euonynms. 



THE CAUSE OF CHLOROSIS. 



Chlorosis may 'result from improper nourishment, i.e. lack of 

 the essential plant foods in the soil, or from the presence in the 

 soil of some chemical which prevents the plant from assimilating 

 those foods. It may be the result of a bacterial disease, 'but it 

 really means that the plant is in an unhealthy state from some 

 cause or another. Exhaustive experiments were conducted in 

 every portion of the Island wherever Chlorosis was present. At 

 first it was suspected that the cause was due to the salt spray, 

 as some of the plants affected were very near the ocean. This 

 idea. was. however, soon abandoned, as many plantations less 

 than 100 yards from the sea had fine healthy green plants, 

 whilst later on Chlorosis was found several miles inland. 



METHODS ADOPTED. 



The method then adopted to endeavour to discover the cause 

 was that of. taking samples of soil from plots where there were 

 affect <H! plants, and soil from the healthy portion of same plan- 

 tation. In some cases only small patches were suffering, and the 

 rest of the plantation was quite healthy, and in other cases the 

 conditions were reversed, that is, the larger portion of the plants 

 were suffering from Chlorosis whilst isolated patches 

 were quite healthy. The result of the chemical analysis of the 

 soils in every case showed that in portions where Chlorosis was 

 present Carbonate of Lime was found in excessive quantities, 

 varying from 1 86 of the total constituents up to 70 76. This 

 was not considered sufficient test of the cause of Chlorosis, as it 

 was known that some of the keys or Islands, near the coast of 

 Florida where the pine thrives luxuriantly, contained a higher 

 percentage of this Carbonate of Lime. 



FLORIDA SOILS. 



Many analyses of the soils of the mainland of Florida, made 

 by Miller & Hume and published in the Florida State Bulletin, 

 Number (>S, prove that the good pineapple soils of that State 

 contain no Carbonate of Lime. It was further shown by these 

 investigations that the type of soil which produced the best pine- 

 apples contains less than 20 per cent, of Carbonate of Lime and 

 about Of) per cent, of insoluble matter. Webber further reports 



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