CONTEOL OF INSECT ENEMIES OF GARDEN CROPS. 



BY S. C. VINAL, M.SC. 



From the time garden seeds are planted until the crops are 

 harvested vegetable plants are subject to the attack of many 

 different kinds of destructive insects. In order to combat 

 these pests successfully it is important that the gardener be 

 thoroughly acquainted with the essential points of insect con- 

 trol. The more the gardener knows about the insects liable 

 to attack his crops the better prepared will he be to control 

 them when injury is first detected. For example, it is very 

 important that the gardener should be able to distinguish a 

 chewing insect from a sucking insect, as such knowledge will 

 aid materially in determining the proper remedy to apply. 



Injurious insects may be divided, roughly, into two classes, 

 according to the manner in which they feed, viz., (1) chewing 

 insects, which bite off, chew and swallow their food, such as 

 cutworms and other caterpillars, leaf-feeding beetles, grass- 

 hoppers, etc.; and (2) sucking insects, which take up food by 

 means of their beaks, such as aphids, squash bugs, scale insects, 

 white flies, etc. If the insect belongs to the chewing type a 

 stomach poison, such as Paris green or arsenate of lead, spread 

 over the material being eaten is usually the best remedy; but 

 if the insect is a sucking species such poisons would be useless, 

 because the insect would insert its beak through the poison 

 and reach a safe place beneath before feeding is begun. For 

 sucking insects, therefore, contact insecticides are essential, 

 such as kerosene emulsion, whale or fish oil soap, and nicotine 

 preparations. 



Many of our insect pests, however, may be most economically 

 controlled, not by the use of insecticides, but simply by adapt- 

 ing certain cultural practices so as to avoid or prevent injury. 



