2 I 



INSECTICIDES. 



Under the heading " Important Insecticides," the United 

 States Department of Agriculture have issued a Farmer' s 

 Bulletin (No. 127^ dealing with some of the more useful 

 remedies employed in America against injurious insects. 

 Many of the pests on the other side of the Atlantic are not 

 unlike those injuring crops and fruit in this country, and thus 

 the measures adopted there may sometimes be advantageously 

 tried here, so that a short summary of the information given 

 in the Bulletin, with notes on the experience gained in this 

 country with similar remedies, may not be without interest. 



For the intelligent and practical employment of insecti- 

 cides it is necessary to understand the nature and method of 

 the injury commonly due to insects. Omitting the many 

 special cases of injury which necessitate peculiar methods of 

 treatment, the great mass of the harm to growing plants from 

 these attacks falls under two principal heads — viz., that 

 caused by biting and that caused by sucking, each group 

 requiring a special system of treatment. 



The biting and gnawing insects are those which actually 

 masticate and swallow some portion of the solid substance 

 of the plant, as the wood, bark, leaves, flowers, or fruit. 

 They include the majority of the injurious larvae, many 

 beetles, etc. 



For these insects direct poisons, such as the arsenicals, 

 which may be safely applied to the leaves or other parts of 

 the plant attacked, and which will be swallowed by the 

 insect with its food, will furnish the surest and simplest 

 remedy. They must, of course, not be employed when the 

 parts treated are themselves shortly to be used for the food 

 •of other animals or of man. 



The sucking insects are those which injure plants by the 

 gradual extraction of the juices, either from the bark, leaves 



