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(1) Poisoned baits scattered lightly between rows and on headlands as 
soon as the first damage by the adults is noticed. The bait that has been 
most effective consists of 1 pound of sodium fluoride, 15 pounds of wheat bran. 
8 pounds of freshly chopped turnips or carrots, and sufficient water to form a 
mash. Apply late in the afternoon to prevent excessive drying out of the 
bait. The bait should be made up several hours in advance of application. 
(2) Crop rotation where possible, to avoid building up infestations 
through continuous cropping with favorite host plants. 
(3) The treatment of seed beds, such as tomato and cabbage, or young 
field-set plants, and crop remnants after harvest, with arsenicals or fluorine 
compounds is advocated. Arsenicals or fluorine compounds should not be applied 
to turnips, mustard, or similar crops, the leaves of which are intended for 
food. 
(4) Field sanitation. All rubbish and weeds where the insect may find 
shelter during inactive periods should be cleaned up. 
MEXICAN BEAN BEETLE 
Finely ground derris or cube root, as well as cryolite, are recommended 
for the control of the Mexican bean beetle. 
Sprays 
Ground derris or cube having a rotenone content of 4 percent should be 
used at a dosage of If pounds in 50 gallons of water or at a rate of 1-| ounces 
in 3 gallons. This gives a rotenone content of approximately 0.015 percent. 
Derris or cube of different rotenone content may be used in the proper pro- 
portion so as to make the finished spray of a content of 0.015 percent rotenone. 
If the ground root contains a higher percentage of rotenone than 4 percent, 
decrease the dosage proportionately. Fcr instance, if a 5 percent rotenone- 
content derris or cube powder is on hand, use only four-fifths as much, namely, 
approximately l\ pounds to 50 gallons or 1| ounces to 3 gallons. 
Extensive tests indicate that no spreader or sticker is necessary with 
derris or cube in water for use on beans. 
Cryolite, either natural or synthetic, may be used at a dosage of 3 
pounds in 50 gallons of water, or 3 ounces in 3 gallons. When cryolite is used, 
treatments with this material should stop when pods begin to form. 
Dusts 
Growers who prefer to dust or are not equipped to spray will obtain 
fairly satisfactory results with any of the following dust mixtures: 
Derris powder or cube powder iuay be mixed with one of the following 
diluents or carriers and used in dust form: Talc, finely ground dusting sul- 
phur, inert clay, tobacco dust, kaolin (china clay), or other inert, finely 
