I 
INTRODUCTION 
5 
are not adapted especially for this region do not thrive 
here. Most of the trees of this region are leafless in 
the dry season, and trees like the nutmeg and clove, 
which are not deciduous, but evergreen, succumb at the 
first dry spell. In this region the annual field crop 
spices — coriander, cumin, chilies — are commonly grown, 
as well as the rhizomatous ginger and turmeric, which 
in this climate lose their leaves during the dry spell. 
Some of the tropical spices, such as capsicums and 
ginger, have a wider cultivation area than most of the 
others, and go almost outside the tropical area, but on 
the whole the areas of successful cultivation are limited. 
It is rather remarkable that so large a proportion of 
the spices of the tropics are successfully grown on islands 
only, or in close propinquity to the sea. Among these 
are nutmegs, cloves, vanilla, clove barks, and perhaps 
we may add cinnamon and cardamoms as island plants. 
SOILS 
The various soils suited for the different spices are 
mentioned under their respective headings. There seems 
to be increasing evidence that with most plants the 
physical characteristics of the soil are more important 
than its chemical constituents. Its water capacity, 
permeability, and capillary conduction or power of 
absorbing water, are its most important characteristics. 
Different crops require different degrees of moisture or 
dryness. Most, however, of the plants described in 
this work require a greater average moisture in an 
accessible and utilisable form than the plants of colder 
climates, as their natural habitat is in the wetter part 
of the tropics. Plants have a great power of adapta- 
tion to surroundings, though at the same time there is 
a limit to their endurance. In soil where it cannot 
obtain its food and water in sufficient quantity a plant 
becomes pale and weak. The leaves show an unmistak- 
able yellow tint instead of the rich green, whether light 
