268 JOUENAL OF AGRICULTUEE OF P. E. 



Kerosene emulsion, when properly made and applied, is one of 

 the best of these and may be used against the hardier insects. When 

 used on tender plants there is some danger of burning the foliage 

 unless great care it taken in the preparation and dilution of the 

 stock. The formula and directions for making the stock solution 

 are as follows : 



^o 



Kerosene 2 gallons. 



Soap , % pound. 



Water : 1 gallon. 



Dissolve the soap in boiling water and pour while boiling into 

 the kerosene. This mixture should be emulsified quickly by pumping 

 it back into itself with a force pump for about five minutes. Properly 

 prepared it should have the consistency of thick cream and should 

 hold up indefinitely. 



For ordinary use on vegetable crops this stock solution should 

 be diluted at the rate of one part of stock to fifteen parts of water. 



Tobacco. — Tobacco is used in several different forms against soft- 

 bodied insects, as a dust, as a liquid spray, and as a fumigaut. 



Nicotine sulphate is the most effective of these tobacco extracts 

 and, owing to its good qualities and ease of preparation, is taking 

 the place of kerosene emulsion in the control of a great many of the 

 soft-bodied insects. It is a standard solution containing 40 per cent 

 by weight of nicotine, and is sold under a trade name. It is usually 

 used at the rate of one part of stock to a thousand parts of water, 

 with soap added at the rate of three pounds to fifty gallons of spray. 



Tobacco concoction.. — This is a somewhat weaker tobacco solution, 

 but is quite effective in the control of plant lice. It is made by boil- 

 ing tobacco stems, leaves or refuse in water at the rate of one pound, 

 to one gallon of water. This stock solution may be diluted slightly 

 according to the resistance of the insect it is used against. 



Tobacco palmers. — These are made by soaking strips of paper in 

 tobacco extract. In the control of plant lice on melons and similar 

 plants, these are sometimes burned under frames thrown over the 

 plants, the fumes given off killing the lice. 



Soaij. — Any good soap may be used as a wash for controlling 

 plant lice and other soft-bodied insects. It is not so effective, how- 

 ever, as kerosene emulsion or the combination of tobacco extract and 

 soap, but may be used when other materials are not available. Fish- 

 oil soap is cheap and is one of the best to use. This and other soaps 

 should be used at the rate of one pound to six or eight gallons of 

 water. 



