residue on the treated surface. 

 The residue does not keep cock- 

 roaches out, but those that come 

 in contact with it are killed. A 

 single treatment in the right places 

 gives protection for several weeks. 

 A liquid insecticide is often the 

 best for use in the home. A dust 

 or water-base spray may be used 

 when there is danger of fire from 

 oil-base liquids. Both a liquid and 

 a dust may be used when cock- 

 roaches are abundant, difficult to 

 control, or firmly established. 



For restricted use 



Chlorthion and Dipterex are ef- 

 fective in controlling roaches, but 

 their uses are restricted. 



Chlorthion may be used any- 

 where except in homes and in 

 places where milk is processed or 

 stored. It should be applied as a 

 1- or 2-percent spray or paint. 



Dipterex should be used only by 

 pest-control operators. It should 

 be applied in a 1-percent water 

 spray. 



Application 



Spray- 

 Apply a liquid insecticide with 

 an ordinary household plunger- 

 type sprayer that produces a coarse 

 spray. 



If large areas are to be treated, 

 compressed-air sprayers, power 

 sprayers, or other special equip- 

 ment may be used. The sprayer 

 should deliver a fairly coarse mist 

 that will wet the surface being 

 treated. If the mist is too fine, it 

 will float away in the air. Apply 

 enough spray to moisten surfaces 



BN-2289 



Oriental cockroach: Above, female: below, 

 male. ( 1 V2 times natural size.) 



thoroughly, but not so much that 

 the liquid begins to drip or run. 



A paintbrush may be used for 

 applying the liquids in cracks or 

 along baseboards. 



Dust 



Apply a dust insecticide with a 

 puff duster of the bulb, plunger, or 

 bellows type. Blow the dust into 

 hiding places that are hard to 



