. 
- 3 - 
Corn meal bait. --This bait is prepared by mixing P pounds of corn meal 
(as finely ground, as for poultry, feed) with 1 pound of cryolite containing 
90 percent of sodium fluoaluminate. A total of 180 pounds per acre of this 
mixture has proved to be about as effective in the control ef the fruitwcrm as 
a total of 90 pounds per acre, of a cryolite dust containing 70 percent cf 
sodium fluoaluminate, or as undiluted calcium arsenate. This corn meal bait 
mixture is cheaper than either.. . of' the .dusts and is scattered over the leaves 
of the plants by hand., no special equipment being necessary, but it has the 
disadvantage when compared with the dusts of being ineffective against the 
pinworm, hornworm, beet armyworm, and russet mite. 
When to t reat * — The first application of either dust or bait for fruit- 
worm c^ntFoi™no'uTd be made as soon as the fruits »f the main crop begin to 
set. At this time, depending on weather and other growing conditions, the 
plants may vary from 1 to 3 feet in diameter but there will be an average of 
about 7 tomatoes per vine, 5 of which should be l/2 inch in diameter or less. 
Th<=> timing of the first application is very important, as under southern 
California conditions it has been demonstrated that a delay of 1 week in 
making the first application results in a marked increase in the number of 
fruits damaged by the fruitworm. 
Number of applications. — Three applications of either the bait or the 
dusts are made at 2-week intervals. 
Poundage of material per acre. --Experiments in southern California have 
shown that 90 pounds of the cryolite dust mixture containing 70 percent of 
sodium f luoaluminate, or of the undiluted calcium arsenate, is the most 
profitable quantity to use in this area. An application of a total of 150 
pounds per acre for three applications proved superior to the 90-pound rate, 
but under the conditions of this experiment the added degree *f control did 
not justify the expense of the additional material. Under war conditions the 
150-pound rate is justified in many fields. 
The experiments indicate that a cryolite dust mixture containing 70 per- 
cent of sodium fluoaluminate is preferable to one of lower strength. The 
three applications at 2-week intervals of 70-percent cryolite or undiluted 
calcium arsenate are made at 20, 30, and 40 pounds per acre, respectively, for 
a total of 90 pounds per acre, and at 25. 50, and 75 pounds per acre, respec- 
tively, for a total of 150 pounds per acre. If the cryolite is diluted to 
contain less than 70 percent of sodium fluoaluminate, the quantity of insec- 
ticide applied per acre should be increased accordingly. Far example, when a 
cryolite dusx mixture containing 50 percent of sodium fluoaluminate is used, 
it should be applied at a total rate of 125 pounds per acre to be equivalent 
t-i 90 pounds of a 70-percent cryolite. Likewise, if calcium arsenate is 
diluted with 25 percent of sulfur for tomato russet mite control, it will be 
necessary to use a total of 120 pounds per acre to get the equivalent of 
90 pounds of undiluted calcium arsenate. 
Three applications *f corn meal bait should be made at 2-week intervals, 
using 40, 60, and 80 pounds per acre, respectively, making a total of 180 
pounds for the season. 
