Florida Agricultural Experiment Station


made by boiling 2 pounds of flour in 2 gallons of water may be
added to 50 gallons of the arsenical solution. (See also page
202).
 A new spreader worked out by the U. S. Department of
Agriculture is a solution of cactus. Thirty pounds of cactus is
chopped fine and allowed to soak over night in 50 gallons of
water. This is strained and the arsenic added. In those parts
of the State where some of the wild species of prickly pears"
or spineless cactus grow, this should make a cheap "sticker."
 Arsenical poisons may be used dry if applied when the
cabbages are wet with dew or rain. It is well to use a filler of
 cheap flour or
 air-slacked
 li m e, mixing
 about sixteen
 parts of the
 filler to one of
 dry poison.
 Of the
 three com-
 pounds, z i n c
 arsenite is the
 least poisonous
 to man or stock.
 Paris green is
 the least satis-
 factory. Its
 arsenic content
 I is variable and
 FIG. 73.-Gulf white butterfly: a, Larva; b, pupa; c, adult, it may burn
 Natural size. (From U. S. Bur. of Ent.)
 tender plants.
In some quarters there is a prejudice against using arsenicals
on cabbages on account of the supposed danger to the consumer.
The amount adhering to the cabbage is so minute as not to
affect the health of the consumer in any way. A prominent
entomologist has calculated that in order to be poisoned by
eating even unwashed cabbages which had been sprayed with
paris green one would have to eat a dozen heads at a sitting.
Ordinarily a rain will wash off so much of the material that it
will not be noticed.
 If the presence of the arsenical is likely to hinder the sale
 of cabbages, it is recommended that they be not sprayed within