PLANT ENEMIES. 
I approach this subject with more hesitation than any I shall 
attempt to treat in this little work, for the reason that the wisest 
of us are so ignorant and the ablest so little prepared to do battle 
for the saving of our plants. It has been stated on good authority 
that no species of injurious insect has ever been exterminated 
and I think it not unlikely that the same may be said of diseases 
which injure or destroy our plants. Yet it is true that new harm- 
ful insects and diseases are continually coming to the front to 
take their dreadful toll from the cultivator. 
There are two classes of insects which do damage to plants; 
first, those which devour the foliage, some during the larval 
stage and others when adult; second, those which pierce the bark, 
leaves, flowers or fruit and suck out the juice. The former, 
which includes all the Lepidoptera, and the Chrysomelids among 
the Coleoptera, are best combated by arsenical poisons applied 
to the plants on which they live; the latter by contact insecticides 
that will form a coat over them and shut off their breathing. To 
the second class belong the Hemiptera in which the Aphides and 
scales are included. These are best combated with the whale 
oil emulsions, but the greatest care should be taken in preparing 
them lest damage be done to the foliage. 
The cottony scale (Pulvinaria sps.) infects Ficus of all species, 
including the wild ones, and it must be combated before it 
reaches the cottony stage, which is an egg stage, and during this 
time the cotton containing the eggs is blown about by the wind. 
I believe that ants sometimes carry these eggs. Use an emulsion 
of whale oil soap for these and spray from the under side of the 
leaves. The Lecanium scales are found on many tropical plants; 
the comptie and Hamelia patens for example, and should have 
similar treatment. Aphides are sometimes quite troublesome and 
should be sprayed with a solution of whale oil soap or gold dust. 
One of the greatest scourges the cultivator has to contend with 
in our area is root knot, the work of a Nematode worm. It 
usually attacks the roots of young plants and in a short time 
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