Bulletin 151, Truck and Garden Insects


enough to be spoiled and then deserted for another. In this
manner, a single caterpillar may spoil two or three tomatoes a
day, and thus do much more damage than would be represented
by the amount of food actually consumed.
 Control.-Arsenicals.-While feeding inside a good-sized
tomato, the caterpillars are, of course, out of reach of arseni-
cals, but their restless habits offer the grower an opportunity
to get at them. They rarely remain in one fruit until their
growth is completed, but after feeding in it for a day or so,
crawl out and attack another. While making their way into
fresh tomatoes they may be poisoned by any arsenical with
which the fruit has been sprayed. Especially when the first
fruits are small, the chances for poisoning the insects are good.
The worms are not able, because of the small size of these
fruits, to eat their way inside, but remain on the outside, and
may eat out sections of several in a single day. These first
fruits are the most valuable part of the crop, which is an addi-
tional reason for applying poison early. A third reason for
applying the arsenicals quite early, when the very first fruits
are the size of marbles or smaller, is that then there can be no
possibility of hindering the sale of the fruit. By the time the
fruit is ready to pick, the enlargement due to growth will have
destroyed all signs of the spray, even if there has been no rain.
The chances of poisoning the consumer, even if the fruit is
sprayed only a day or so before picking, are negligible. Using
lead arsenate at the rate of 2 to 3 pounds to 50 gallons of water,
the amount that would be left on each fruit would be so small
that the stomach of the consumer could not hold enough toma-
toes to enable him to get an injurious dose of the arsenical,
even if the tomatoes were not washed before eating. However,
any trace of the spray on the fruit at the time of marketing
would probably lower the price. For this reason it is recom-
mended that the spraying be discontinued a week or ten days
before the first picking. The first spraying should be given
when the earliest tomatoes are the size of small marbles. A
week later, if there is no rain, a second spraying can be given.
Should it rain shortly after the first spraying, it would doubt-
less be advisable to apply a second spray within three or four
days after the first. Even a single spraying will greatly reduce
the percentage of infestation.
 It is recommend that, in using the lead arsenate spray, 2
 pounds of lime be added to the liquid to prevent burning.