INSECTICIDES. 



509 



Quassia extract may be bought, but the strength of it is uncertain. This is a very useful 

 .insecticide for use in attack's of aphides andthrips, and, if lib. of flowers of sulphur be added, 

 for red spider. 



RESIN WASH. — One pound of resin, lib. of caustic soda, and i.V gills of soft soap 

 should be put into a closed vessel, covered with 4m. or Jin. of water, and boiled for an 

 hour or more, until the liquid has a dark' brown colour like coffee. Before using, add four parts 

 of water to one of the mixture. This is strongly recommended by the American authorities as 

 a wash for plants, etc., attacked by scale insects. 



SOOT. — This, when fresh, is useful in keeping grubs away from plants if laid thickly 

 on the soil round the plants and then worked in the earth. 



TOBACCO. — This is one of the best-known, and at the same time one of the most 

 useful, insecticides. To make tobacco water, boil .lib. of tobacco in 1 gallon of water. The 

 liquor, when strained oft, should be diluted with water if necessary until it is of the colour of 

 tolerably strong tea. Soft soap may be added at the rate of 2lb. to every 3 gallons. It may 

 also be used powdered, or in the form of snuff, to dust plants with that are infested with 

 aphides. It is also used in greenhouses for fumigation, and a very strong tobacco liquor is 

 effective in killing most greenhouse pests when gradually evaporated over a small stove. 



Besides the insecticides already enumerated, there are various others sold, with 

 directions for their use, which are more or less useful. They are, however, generally more 

 costly than those that can be made at home, and it is difficult to be certain that the ingredients 

 are quite fresh, but then there is no trouble in making them up. Insecticides must be used 

 with extreme caution, otherwise the remedy proves worse than the evil. Many failures 

 may be attributed to their reckless use. Always apply them according to the printed 

 directions, and it is better 1o use them too weakly than to apply a strong dose. It must be 

 remembered that the insecticides are strong, and hurtful if overdone. 



A GARDEN SEAT. 



