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 belie ve 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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