4 i6 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



various commercial brands varies somewhat but as a rule nine 

 to twelve gallons of the concentrated solution to 100 gallons of 

 water should be used in treating trees in the winter for such 

 insects as San Jose scale and blister-mites. For use in the 

 summer for fungus and soft-bodied insects, such as aphids 

 and young scale-insects, the proportion should be about 

 two or three gallons of the concentrated solution to 100 gallons 

 of water. It has recently been demonstrated that in some 

 instances sulphur-lime solution may take the place of arsenical 

 sprays as it acts as a stomach poison as well as a contact in- 

 secticide. Sulphur-lime, three gallons to 100 gallons of water, 

 has been used with some success in controlling the codling 

 moth. The addition of a little arsenate of lead will probably 

 be found advisable. 



It is somewhat difficult to prepare sulphur-lime wash with 

 uniformity unless one is well prepared for this work. The 

 best plan is to obtain one of the bulletins issued by the state 

 in which the orchardist lives, and follow carefully the directions 

 given there. The following formula is one that is often used: 



Unslaked lime 5 pounds 



Flowers of sulphur n pounds 



Water 5 gallons 



Put a little of the water in a kettle or boiler over a good fire; 

 add the lime and after it has started to slake sift the sulphur 

 over it adding enough water to maintain a thin paste. After 

 the slaking and mixing are completed add more water and boil 

 for atxmt one hour adding enough water from time to time to 

 make up for evaporation. If properly made the mixture will 

 be of an amber color, and there will be but little sediment. 

 This is a concentrated solution which, before using, should be 

 diluted to the strength indicated above. 



Kerosene emulsions or distillate oil emulsions are often used 

 for many of the soft-bodied sucking insects. The follow- 

 ing is the standard formula for kerosene emulsion: kerosene 

 2 gallons; soap (preferably whale-oil soap) 1/2 pound; water 

 i gallon. The soap should be dissolved in the water heated to 

 boiling and the kerosene then added. Churn or otherwise 



