The record-union., 1896-03-29
TIE GOBLIN MOTH.
Important Paper Before the State H0Tti-
cultural Society.
Paris Green Used by Frult-Growers
Adulterated So as to be Com
parativeiy Valueless.

| At a recent meeting of the State
Horticultural Society B. M. LeYong
read an interesting paper on the Goblin
moth, in which he said:
The Goblin moth and its habits are
| too well known to require a. descrip-
ton at this time, but those desiring such
| information should consult the reports
and bulletins issued by the State Board
| of Horticulture. What is most inn
portant to know is, what remedy to
apply and when to apply it to secure the
best results.
The remedy now universally used is
Paris green of high grade, or pure
state The substance sold under the
name of Paris green is, chemically con-
sidered, an aceto-arsenite of copper.
and is known in the arts and to the
trade by different names, such as
French green,'' "Mitis green,''
Emerald green,' "Schweinfurt greeng'
etc.
One of the methods formerly em-
| ployed in the preparation of Paris
green, according to the chemist Liebig,
involved the simple treatment of the
crude and freshly -precipitated Scheele's
green or copper arsenite, with wood
vinegar, from which source the acetic
acid of the final product was derived.
In the method generally adopted for
the preparation of this substance,
| arsenious acid (white arsenic) and ace
tate of copper (verdigris) are employed;
both are dissolved separately in hot
water, and boiling solutions are mixed
together, the precipitated coloring mat
ter being allowed to settle.
Paris green is normally bright crys-
talline powder, insoluble in water. but
changing in color when boiled with
water for some time. According to the
chemist Ehrnlann, the composition Of
pure Paris green is as follows: Copper
| oxide 31.29, arsenious acid $3.50, acetic
acid 1906.
The purest grades of Paris green,
however, show slight variations from
the proportions given above, but when
used as an insecticide for the Goblin
moth, should contain at least so per
cent. of combined arsenious acid and
fruit-groWers who are in doubt as to
it's purity and quality should have the
same tested by sending samples to Pro-
fessor Hilgard at Berkeley.
In the past two years enormous guam
titles of Paris green have been sold to
growers, much of which was of very in
ferior quality. The results were equal
ly as poor, and many growers have thus
become prejudiced against it's use
Samples of Paris green have been exam
ined, with astonishing results. Several
| samples, although of nearly the same
shade of color as the pure Paris green,
were found to be a mixture of Prussian
blue and chrome yellow, clay and chalk.
Others were found to contain no arsen-
ious acid. In many cases the fault lies
with the fruit-growers themselves, for
we have continually advised them to
use the pure article, which costs twenty
cents per pound. This advice has been
disregarded to a considerable extent,
and the cheapest grades hsve been
purchased, with little or no results.
Then again, Paris green has been
applied at the wrong time, and owing
| to this cause many complain that spray
ing has been of little or no use to their
crops. In travelling about the State I
have always found people spraying
when there was no occasion for it, as
the fruit had grown to such size as to
| render spraying of no avail; others
| sprayed too soon, before the petals
had fallen, and before the moth
had deposited her eggs. Spraying for
the Goblin moth, to insure the best re-
suits, must be done at the proper time,
and if not properly done is waste of
time and material. Those that spray
at the proper time and with the great
est thoroughness are the ones whose
fruit commands the best prices and
is much sought after. To spray for the
Goblin moth only once means that you
will have large percentage of worIny
fruit and larger percentage if sprayed
at the wrong time. For instance, what
good would spraying be if done after
the apples or pears have attained the
size of Walnuts, when by this time the
worm is far into the fruit and beyond
the reach of poison? Also, suppose
one spraying was done at the proper
time and them the work abandoned,
allowing the moth to deposit her eggs,
and the little worm to enter the fruit
the second or third week when the
strength of the poison has become diff
fused and no longer effective?
The Goblin moth in some sections is
widely distributed, and spraying to
save the apple and pear crops has be-
come necessity; in other words, it
insures the crop, which, without spray
ing, is of no value.
To be successful the following re-
quirements must be fully carried out:
1. Spray with Paris green of the best
quality, using one pound to 200 gallons
of water.
z. Spray apples and pears just after
the petals of the blossoms fall.
8. Spray the second time sixteen davs
after the first application.
4. Watch matters closely and if
necessary. spray the third time three
weeks after the second application: but
this may not be required. depending
largely upon the season.
In the discussion of President T,e-
longs paper it was brought out that
a large percentage Of the Paris green
used by fruit-growers is so much adul-
terated as to be of comparatively little
worth as an insecticide Anything
called Paris green and offered for sale
at less than say % cents a pound in ten
to twenty-dve-pound lots, may be set
down as too much adulterated to be of
much use. Twenty cents a. Mound in
kegs holding go pounds. is as CHEAP
as a fairly pure article can be obtained
in San Francisco from reliable wholesale
druggists. There is no trouble i'm get
ting practically pure article If or
chardists are willing to pay the above
prices; Dut 1T may as well be under
stood that the stuff offered at 10 to Is
cents per pound Is not a profitable Paris
green TO buy, for the reason that it
does not contain sufficient poison to do
the work required IT is a ,.,e.+<, ,,e +;yoe.