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port, and the soil often contains, especially when newly planted, a 

 large proportion of humus or decayed vegetable matter. 



The disadvantages are the occasional difficulty in draining, and 

 liability to floods, owing to the flat nature of the ground, the frequent 

 somewhat impervious character of the soil, and the fact that, as might 

 be expected in material that has been thoroughly lixiviated, soluble 

 bases, lime, alkalis, &c, have been largely or almost entirely removed. 



It is clear that manuring with lime, basic slag or other chemical 

 manures will supply material which is naturally deficient in such 

 soils. 



The alluvial flats of the Oropuche (E.) Sangre Grande, Cunapo 

 and El Branche Rivers afford good instances of cacao estates 

 established on alluvium, and the yield of cacao, I am informed, is 

 o-ood ; the boundaries of the alluvial flats have been indicated on the 

 maps of the Eastern district for this reason. 



At Mayaro, Guayaguayare, along the main Southern Road and in 

 the Northern range alluvial soils are planted with cacao also. 



(2.) The Tertiary clays afford soils, which, though rich as regards 

 chemical constituents, are seldom so suitable as regards mechanical 

 condition for cacao growth. They are usually very stiff and imper- 

 vious, requiring a great deal of draining when the land is' level, and 

 being liable to landslips on hilly or undulating ground. 



These clays vary greatly in composition in different localities, 

 some being gypseous, some calcareous and some containing bands of 

 ferrous carbonate nodules. The Government Analyst, Professor Car- 

 mody, has recently discovered that a thin band of ferrous carbonate 

 from one of the Tertiary clays contains 13 per cent, of phosphate of 

 lime, which would form a very valuable addition to a soil formed 

 from the disintegrated rock. If similar or even much smaller per- 

 centages of phosphate are present in the majority of the iron-car- 

 bonate nodules, the soil formed from the rock containing them should 

 be the most valuable of the Tertiary clays for cacao planting. 

 Another beneficial effect of the nodules is that their presence tends 

 to loosen and lighten the heavy clay soil to some extent, while where 

 they are present there is usually an appreciable quantity of lime 

 present also. 



The gypseous clays on the other hand are probably too stiff for 

 the best results, forming a soil which is apt to be sour, though the 

 solution of strings and lamina? of selenite, where it is present in large 

 quantity, must enable the soil to drain more easily. 



Forking round the trees and the addition of farm-yard or pen 

 manure must evidently have a favourable effect on these soils by 

 loosening them and supplying nitrogen, while chemical manures 

 would probably be of less value owing to the abundance of bases 

 naturally present in the disintegrated rock. 



The Manzanilla district affords good instances of cacao grown on 

 the blue clays containing iron-carbonate nodules and a proportion of 

 lime. Instances of cacao estates on gypseous clays may be seen in 

 Savana Grande. 



