Entomological Department. 329 



striking success than we obtained by tbe use of the emulsion against 

 this Pear Leaf Blister Mite.* 



The emulsion can be applied with equal effectiveness at any time 

 after the leaves have fallen in autumn and before the buds have begun 

 to swell in the spring. Dilute the emulsion f with not over five to seven 

 parts of water. Spray the tree thorouglily from every side, taking 

 especial care to hit every terminal bud, for this is where most of the 

 mites congregate. There is no danger of injuring the tree with this 

 dilution of the emulsion. 



In this manner the Pear Leaf Blister Mite can, we believe, be nearly 

 exterminated in an orchard by a single thorough spraying. The 

 method also has the great advantage of being cheap, easy to apply and 

 practicable on a large scale. This spraying of the tree in winter with 

 so strong an emulsion may also destroy some of the adults of that pest 

 most dreaded by all pear growers — the Pear Psylla — which is then 

 in hibernation in the crevices of the bark on the trunk and large limbs; 

 therefore spray the tree all over. 



*Mr Crawford doubtless first suggested the use of kerosene emulsion 

 against this pest in winter. He said: "Tlie habits of the mite in the winter 

 time afford a clue to one method of treating it. For this purpose I would 

 recommend three washes to be experimented with, viz . : [fCerosene emulsion, 

 one to fourteen; caustic soda, say four, eight and twelve ounces to the gallon; 

 and sulphuretted lime." 



He tried no experiments and our results show that to dilute an emulsion 

 would be of little arail. Mr. Crawford's recommendation was unknown to us 

 until after we began to write this article. 



Other authors have recommended the use of the emulsion when the mites are 

 eaving the buds or while migrating to the buds. It would be effective if the 

 mites could be hit at this latter time, which would, however, necessitate very 

 careful watching with a good lens to determine the exact time to make the 

 application . They do not leave the buds in the spring, but attack the leaves 

 while yet in the bud; and the mites are out' of reach in their galls before the 

 leaves unroll. 



f To make the emulsion, thoroughly dissolve one-half pound hard or soft soap 

 in one gallon boiling water . While this solution is still very hot add two gal- 

 lons of kerosene and quickly begin to agitate the whole mass through a syringe 

 or force-pump, drawing the liquid into the pump and forcing it back into the 

 dish. Continue this for five minutes or until the whole mass assumes a creamy 

 color and consistency which will adhere to the sides of the vessel, and not glide 

 off like oil. It may be now readily diluted with cold rain water, or the whole 

 mass may be allowed to cool when it has a semi-solid form, not unlike loppered 

 milk. This standard emulsion if covered and placed in a cool dark place will 

 keep for a long time. In making a dilution from this cold emulsion, it is 

 necessary to dissolve the amount required in three or four parts of boiling 

 water, after which cold rain water may be added in the required quantities. 



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