3G4 1vei'()j;t of xiiK Depakt.mext of Exto.molocjy of tiif 

 METHODS OF TREATIMEKT. 



FORMULAS OF SPRAYING MIXTURES. 



1. 



Nicotine extract 2.7 per ct. (Black Leaf) 6 qts. 



Water 100 gals. 



Soap' 2 to 5 lb3. 



or 

 Kerosene emulsion 3 gals. 



2. 



Nicotine extract 40 per ct. (Black Leaf 40) 14 to % iit.2 



Water 100 gals. 



Soap' 2 to 5 lbs. 



or 

 Kerosene emulsion 3 gala. 



DIRECTIONS FOR SPRAYING. 



In spraying, two objects should be kept in mind, — (1) to hill 

 the winged thrips working in and about expanding buds and blos- 

 som clusters to prevent injury to the tender flower and leaf parts; 

 and (2) io destroy the larvce after petals drop to reduce the num- 

 bers of insects luhich will mature in the ground. 



1 The addition of soap or kerosene emulsion to the nicotine preparation 

 increases its adhesive and penetrating properties. According to Foster and 

 Jones. (U. S. Dept. Agr. Ent. Circular 131), a combination distillate-oil 

 emulsion and nicotine solution is given preference to all other sprays. The 

 spreading properties of the oil makes this mixture especially efficient against 

 the thrips concealed in the buds. 



Directions for making kerosene emulsion are as follows: 



Kerosene 2 gals. 



Whale-oil or fish-oil soap 1/2 lb. 



Soft water 1 gal. 



Dissoh'e the soap, which has been finely divided, in one gallon of boiling 

 water. Remove the vessel from the stove and add the oil. Then agitate the 

 mixture violently for from three to five m'inutes by pumping into itself un- 

 der high pressure until a creamy mass is formed, from which the oil does 

 not separate. Fruitgrowers are advised not to employ an emulsion which 

 shows a separation of the oil as applications of such preparations may 

 cause injuries to the trees. 



2 Experiments' conducted in California (See Circular 131 mentioned in 

 Footnote 1 ) show that the Black Leaf 40 may be used effectively in the 

 proportions of one-half pint of the extract to one hundred gallons of water. 

 In the Station's tests three-quarters of a pint was always used. Future 

 experiments may show that the latter amount is unnecessarily strong and 

 that the smaller quantity of the nicotine extract may be safely used. It 

 ehoiild also be stated that on account of greater concentration the express 

 and other transportation charges for Black Leaf 40 are much less than for 

 the Black Leaf, and during the past season the former was, on this account, 

 preferred by pear growers about Germantown. 



