6 
SPICES 
CHAP. 
or dark, of the normal plant. It makes but little 
growth, and is liable to attacks of insects and fungi. 
It is, in the first place, of the greatest importance to 
select a suitable soil. Sandy spots, except in the case 
of cinnamon, water-logged soils, and soils formed almost 
exclusively of vegetable debris, or impregnated with 
salts, should be avoided. It is possible in most of these 
cases to improve the soils, but the cost may be too great 
to be worth while. In prospecting for a good site for 
the estate, the ground should be dug to a depth of at 
least two feet, in order to form an idea of the subsoil, 
which is often different from the surface layers. 
DISEASES 
The diseases from which plants suffer are due to 
insects or fungi. Bacteria, which play the chief part in 
diseases of animals, seem seldom to be the cause of 
disease among plants. 
The known diseases of each plant are described in 
each chapter dealing with the species. The careful 
watching for disease is one of the most important duties 
of the planter. No attack, however mild, should be over- 
looked as unimportant. In an outbreak a disease often 
begins very slowly, a plant here or there dies, and no 
notice is taken of this. More are attacked, and usually 
the disease appears in patches about the estate. Too 
often it is not until a considerable number of plants 
are dead or dying that the planter takes any steps to 
stop it. Sometimes the disease assumes a virulent 
nature, spreading rapidly from each centre of infection, 
and before the planter has time to fairly combat it, 
the estate may be ruined. In any case, when it has 
once reached the virulent stage the expenses of checking 
it will be great, while earlier action when the disease 
first showed itself would have cost but a trivial sum. 
A yellowing of the leaves of a plant is usually a 
sign that it is in an unhealthy state. It may be due to 
starvation from destruction of a portion of the roots, or 
