VARIOUS INSECTICIDES 299 



Completely dissolve the caustic soda in the water, and then add 

 the fish-oil very gradually, under constant and vigorous stirring. 

 The combination occurs readily at ordinary summer temperatures 

 and boiling is unnecessary. Stir briskly for about twenty minutes 

 after the last of the oil has been added. (New York Experiment 

 Station.) 



Soap and tobacco. Dissolve 8 pounds of the best soft soap in 12 

 gallons of rain-water, and when cold add 1 gallon of strong 

 tobacco liquor. For plant-lice. 



Soda and aloes. Dissolve 2 pounds of washing-soda and 1 ounce of 

 bitter Barbadoes aloes, and when cold add one gallon of water. 

 Dip the plants into the solution, and lay them on their sides 

 for a short time, and the insects will drop off. Syringe the plants 

 with clean, tepid water, and return to the house. For plant-lice. 



Sulfur. Fumes of sulfur are destructive to insects, but should be 

 carefully used, or plants will be injured. The sulfur should be 

 evaporated over an oil stove, until the room is filled with the 

 vapor. The sulfur should never be burned, as burning sulfur 

 kills plants. For greenhouse use. See p. 258. 



Sulfur and water. To 3 gallons of weak soap suds add 1 pound of 

 flowers of sulfur and stir thoroughly. Apply as a spray. For 

 red spider and mites. 



Tanglefoot is a sticky commercial substance much used for banding 

 trees. See under BANDING, p. 286. 



Tar is sometimes used to prevent the female and wingless canker- 

 worm from ascending trees. The tar should be placed on cotton, 

 or some material which will prevent it from coming in contact 

 with the bark, and a band of the preparation is then placed 

 around the trunk. Care must be taken to see that the tar does 

 not injure the tree. 



Tarred paper may be rolled loosely about trees to keep away 

 mice, but it should be removed before warm weather. It is 

 sometimes recommended as a preventive of the attacks of borers, 

 but it very often injures trees, and should be used, if at all, 

 with great caution. 



Tobacco. 1. Stems, placed on the walks and under the benches of 

 greenhouses, for plant-lice. Renew it every month. 

 2. Tobacco-water, used with whale-oil soap. 



