-: 5^) - 
Dnrris powder (U percent of rott~noni^) ?t th-"^ rate of 2 noundp -op-r 
100 fjallons of watrr plus a'-^^ut 2. •oouiid?; (r'-ry "bapif) of coconut oil <=io?,r> 
killed 9i^ percent of tho larva^ p.nd B2 percent of the adult<? on to-nptooq, — 
Manschke (272) in 1^37. 
Derris austs hnve ^iven satisfactory rosult^ on the Colora'^.o p'^tato 
■beetle. — New Jersey , A^cricultural Eyporinent Station (_297) in 1Q37. 
Smith ( 339. ) iJ^ 1937 report -~d that a spray of derris •'^owder (^ rercen 
of rotenone) at 2 pounds per 100 gallons of water plus 1-7/3' pounds of coco 
nut oil soap (anhydrous tasis) killed 9S percent of thp' larvae and 92 loer- 
cent ^f the adults of the Colorado potato "beetle 2U hours aftf^r anplic^ti-in 
A preparation called Pirox, in use in France f^r the control of the 
Colorado potato "beetle, contains derris, ^sulfur, and co^p'^r« .Reference is 
made to varicup derris fixtures "entioned in the literaturr- for the control 
of this insect.--v;ahl (h£^) in 1^37. 
The Colorado r)Otato teatle on p.otatoe? was kill--d "by a product con- 
taining? 12 percent powdered Lonchocar-pus nicou root (of 6 percent rote- 
n'^ne content) and oc p*^rcent of talcu-i. , according: to Sta'^;li<'seT:nentP5 R'-'tonia 
in lQ3&.in a letter t-' R. C. Roark, 
The United States Bureau of 3htor\olo,ry and Plant Quarantine, Divisio 
of Control Investi/vati^ns ( 397 ) in I930 issued its third report of terts qn 
the insecticidal value of various conpounds. Results of tests with'derris 
against f'^urth instars of the Colorado potat'o "b^'^otle wero r'^ported as folio 
Micro£:ranR 
Material (dust) p'-^r so. en. Effect 
Derris (rotenone 5.^ percent; 125 or Permitted sli^rht fe^d- 
total extractives 15.5 p^^rcent) 110 inc and killed 1*^0 
percent in U'o hours, 
Derris + talc (rot--none 1 percent) 1'"'0 Do-. 
Derris-talc (rotenone O.5 "oercent) 23O Do, 
Cu'ce powder (rotenone k,h percent; 
tot--i extracti^'es 20,7 perc-'-nt) lUo Do. 
At;icide DC-U (rot-'>n"ne 0,6 percent) at th'-^ rat.- of U r^ounds Tier 
100 gallons of water (0.0"3 r:,ercent rotenone in spray) killr-^i fron 50 to 
100 percent of the b<=etles in q6, hours, — Af:icidr- La'-oratories (_6) in 103^» 
Desaynard ( lOl ) in 193'-' discusg-d the ad-"-anta,:'=s and li-^it-^tiong 
of rotenone as an insecticide, A jjowder cont'^in.infr rotenone, sta"tiliz."d 
accordinc; to a- patented pfecesr^, retained full toxicity to C'^lora.do tiotato 
"beetle larvae when eyeoped to li^ht foi' 110 hours, whereas the nonsta-.-ilizei 
powder dropped t'-^ 12 norcent of its efficecy in this tine. 
