The Punta Gorda herald. [volume] (Punta Gorda, Fla.) 1893-1958, 1915-02-18
A SPRAYING SYSTEM FOR
FLORIDA CITRUS FRUITS
The Crop, It is Believed, Can BE
Increased At Least 25 Per
Cent. AT Small Cost

| pests 10 Gurus 1fultS Ill TloIlod
which on the average amounts
to from Is to 40 per cent. Of thu
crop, the Department of Agricul
ture has worked out spraying
scheme which has given striking
results in the three years that II
has been practiced.
Practically all of the damage
that insects do to citrus fruits III
Florida can be attributed to six
species. The most destructive is
the citrus whitefy; the second the
purple scale; and the third the
rust mite. To do away with these
pests Government specialists ad-
vocate four sprayings, two OF
which are primarily intended to
kill the whitefy and scale insects
and the two others to destroy the
rust mites. The number OF
sprayings, however, is not fixed
but depends to large measure
upon the thoroughness of the
work and the seriousness of the
infestation.
The first spraying should be
done in May after the adults of
the first brood of whitefies have
disappeared and before the ap-
pearance Of those of the second
brood. At that time the fruit
should be an inch or more in di-
ameter. A paraffin-oil emulsion
is used, prepared in accordance
with the formula described in Blu
reau of Entomology Circular 1858.
Following is the formula:
Whale oil soup, s pounds or one
gallon,
Parafin oil, 2 gallons,
Water, gallon.
The mixture is prepared by ad-
ding the oil very slowly to the
soap, the whole being vigorously
stirred throughout the process.
1t is important that the oil
should be added in small quanti-
ties and the stirring be sufficient
to keep oil and soap in the
form of an emulsion. After the
required amount of oil has been
added and after free oil has ceas-
ed to appear on top of the soap,
the water is slowly poured in.
After being prepared in this way
the mixture is diluted by the adj
dition of fifty gallons of water to
l of mixture, which leaves a spray
approximately one per cent oil.
This is the maximum strength re-
quired for whiteflies and purple
scale.
In June or July the rust mites
should be attacked by a lime
sulphur solution of the strength of
to so or l to IS, This spraying
should be done when the maxi
mum number of rust mites have
made their appearance and be-
fore any russeting appears. 1t
will also kill some scale and
whitefies, but should not be relied
upon for this purpose. Some
time between August IS and Oc-
tober 31st, the trees should be
sprayed again with the parafin
oil emulsion in order to kill all
the whitefy larvae which are the
progeny of the third and last
brood. The earlier these are
killed the better it is for the tree.
This spraying will also serve to re-
move the sooty moulds from the
trees and from the fruit, enabling
the sun to color it.
In November or December it is
frequently desirable to spray a.
gain with the lime-sulphm solu-
ton in order to kill off what rust
mites there may be.
The cost of following such a
scheme is estimated at from 20 to
35 cents a year for each tree.
One grower was able to carry it
out at cost of three cents per
,ox of fruit, and on the other hand |
t costs another s cents. Eight |
cents may be taken as the maxi
mum figure. In return for this
outlay the trees yield not only
more abundant but much larger
'ruit. The increase in the size
If the fruit alone should result, it
S estimated, in an increased pre-