Appendix 155 



sidered, emulsions are desirable since they eliminate the fire 

 hazard associated with an oil spray. 



Wettahle powders containing up to 50% DDT mixed 

 with pyrophyllite make effective residual sprays for barns 

 and other outbuildings where one doesn't mind the white 

 deposit on the walls. For use, sufficient powder is added to 

 water to giYQ a 2% % DDT mixture. A 5 % mixture is not 

 needed because the powder, unlike the oil solutions and 

 emulsions, does not penetrate into porous surfaces. About 

 1 gallon of the 2% % spray should be used for approximate- 

 ly 300 square feet of surface. 



Paints containing up to 6% DDT are available, and 

 can be used where residual aaion is desired. They afford 

 protection for approximately the same length of time as the 

 usual types of residual sprays. 



On Cattle and Horses 



For the control of houseflies, stable flies, and horn flies 

 on cattle or horses use a 2 /4 % DDT emulsion or dispersion 

 of wettable powder. Apply the spray at the rate of about 1 

 quart per adult animal, paying particular attention to the 

 belly, rump, and back. A single application should effec- 

 tively control the flies for at least 2 weeks. An alternative 

 method is to dip the animal in an emulsion of about % % 

 DDT. On the average, about 2 gallons are required for 

 each adult animal. 



HORNETS 



( See WASPS and hornets ) 



LICE 

 On Humans 



There are three types of lice that affea humans: body 



