INSECTS INJURIOUS TO THE ORANGE. 421 



Strong tobacco- water, heated to about 130 F., has also 

 been used with some success, more particularly on the young 

 broods. 



Diluted emulsions of kerosene oil are also valuable agents 

 in destroying the different species of bark-lice, as well as 

 many other injurious insects. Emulsions prepared in the 

 following manner have been found very efficient in several 

 series of experiments conducted under the direction of the 

 Department of Agriculture at Washington : 



No. 1. Kerosene oil, .... 2 gallons. 

 Common soap, . . . . J pound. 



Water, 1 gallon. 



Dissolve the soap in the water and heat the solution, adding 

 it, boiling hot, to the kerosene. Churn the mixture with a 

 force-pump and spray-nozzle for five or ten minutes, when the 

 emulsion, if perfect, forms a cream which thickens on cooling 

 and should adhere without oiliness to the surface of glass. 

 Dilute this emulsion with from 10 to 12 times its bulk of 

 cold water, and spray it on the foliage. 



No. 2. Kerosene oil, .... 2 gallons. 



Sour milk, 1 gallon. 



Warm the ingredients to a blood-heat and emulsify in the 

 same manner as is directed for No. 1, and subsequently dilute 

 with from 10 to 12 parts of water before using. 



No. 3. Take the white of two eggs, three tablespoonftils 

 of sugar, a pint and a half of water, and two pints and a half 

 of kerosene oil. Emulsify with a force-pump and spray-nozzle, 

 when a cream-like compound will be produced, which should 

 be diluted with from 10 to 12 times its bulk of water. 



It is said that these diluted kerosene emulsions, when prop- 

 erly prepared, so that the oil does not separate, are more effect- 

 ive than the alkaline washes, and that they do not injure the 

 trees. 



For the application of these fluids several forms of portable 

 pumps have been devised, in the selection of which the fruit- 

 grower should be guided by his own requirements. Where 



