^* I^ixod \:Ltb. food bdi 1;.H:. — Irx Ncr; ;iy rc-.t hcbitcts, 1 p^rc>ijit of ^n?U in 

 the bait is ade ,aato. ichors b.^tii Korvjays -and blacks aro orosont, 5 percent 

 should b'c; used. The; bait and the poison should be mixed as vjvenly as possible. 

 To do this, the a::TTI' may bj bl.;nded >;ith 5 tiiiiys its own vjoight of flour, and 

 this mizture dusted ox'<;.r the food as it is being stirred, --^ny palatable food 

 attractive tc rats ma;/ bo' used, 



;3. Dusted over food piles .— For using AIITU in this >Jay, it is suggestod 

 that the rats be prebaited to eat at cortai:. locations through the repeated 'ex- 

 posure of small piles of unpoiscned food for several nights. Then the usual 

 piles of food are placed and pure rJ'TTU- is dust-ed over them and the surrounding 

 floor until. .a.. thin fiLm has be^n sprin:':led- on the feed and about a foot on oach 

 side. . - ■ 



3. Dusted over the surface of "^'ater . — This method is not very effective, 

 as ^ITTU is insoluble and tends to collect around, the edge of the container. It 

 is not recommended' b; the Fish and Wildlife oer*v ice. 



4. Dusted along run' Jays . — .-attempts to increase thv^ efficiency of ^u'TU led 

 vjorkers in the United Sta^tciS Publi-c-Health' Service to try dusting the powder on 

 rat runiJays. This unique \^ay of using it gave somevjhat bett.;r Jesuits in the 

 blacjz rat ar^as. ' llodifications in formulas' follovjed' the first tests, and .at 

 present the mixture becoming more or less standard is: dO percent A1J7U,. 2 per- 

 cent DDT, and 78 percent pyrophyllite.' ' This formula vjill tend to control the 

 rats and the fl^as on them at the same tim.e. 



5', Dusted in burrcv.'s . — This method has been used by both Dr., Richtor and 

 the Public Health Service. The pure j-:J:"TU or the composite formula given above 

 is pumped into the burro'iA; with, a foot-pum.p duster such as is used in the appli- 

 cation of calcium cyejiide dust.'' .'.'... , - ■ 



The Fish and Wildlife Service, which' has beeh experimenting xvith AMTU since 

 late in 194^, concludes that it 'is usef ul' vvhen used in a. rotation of poisons; it 

 ■ Should not follovj itself In; any operation. It '/jill be more satisfactory in areas 

 vjhere Norways ccmpos'j the entire rat pcpulction. It is practically ineffective 

 against mice. 



^^■ITUis covered by a public patent made out to the Secretary of "Jar, and 

 ?.t least one manufacturing company' is producing it commercially. 



'NCTS. — ril^lU is a now poison, and, the VJildlife Hesearch Laboratory, Fish 

 cud Wildlife Service; 545 Custoia House, Denver, Cplo., Kould be glad to .receiv.: 

 reijorts of any unusual ox •-■^rl oncer's vjith it. 



6758 



