INSECTICIDES. 



and similar preventive measures will control mosquitoes, 

 and general cleaning up will do away with flies? Many 

 insect enemies of cultivated plants breed on weeds. Either 

 treat the "weeds" as cultivated plants or get rid of them. 



Insecticides may be roughly divided into four classes: 

 stomach poisons, contact insecticides, repellants and gases. 



Stomach poisons are for such insects as chew vegetation. 

 Nearly all of them contain arsenic in some combination 

 and, if there be too much water-soluble arsenic, will burn 

 the foliage. Now that insecticides are under government 

 supervision, it is fairly safe to buy any standard brand 

 and use it according to the directions on the package 

 these notes are for home-gardeners who would buy insecti- 

 cides in small quantities and such quantities should not 

 be purchased "loose." These directions will almost 

 certainly call for lime, in order to neutralize the traces of 

 soluble arsenic, and possibly resin-soap to make the poison 

 stick to the leaves better. In spraying, cover every part 

 of every leaf, if possible. For house-plants, an ordinary 

 medicine atomizer is excellent. For garden plants, get a 

 spray fitted to the number and size of the plants to be 

 sprayed. Poisoned Bran Mash for grasshoppers, cut- 

 worms and the like, is made by mixing I part, by weight, 

 of Paris-green or London-purple with 25 parts of bran and 

 enough cheap molasses, diluted to about half -strength with 

 water, to make a stiff paste. 



Paris-green, etc., will poison humans if enough be eaten, 

 but it is estimated, for example, that one must eat twenty- 

 eight cabbages (that have been sprayed or dusted in the 

 ordinary way) in order to swallow enough poison to be 

 harmful. Hellebore is sometimes used because it is less 

 poisonous to man and to other animals with less than six 

 legs, but it is expensive and deteriorates with age. It may 

 be used dry, diluted with about 8 parts of flour, or as a 

 spray, one ounce to a gallon of water. If poisons are 

 applied dry, the application should be made on a still 

 morning before the dew has dried. 



Contact insecticides arc used against sap-sucking 

 insects, which would stick their proboscis right through a 

 layer of stomach poison and not be bothered by it. Chief 

 among such insects are the aphids. Contact insecticides 



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