Los Angeles daily herald., 1888-02-12

report recently received from o.,. p :, :
my agents, Mr.. Albert Koehsjs -.
experime ts in this direction a.
some further experiments with rerin
compound and arsenic acid.
MR.. KoEBELE's REPORT.
In the main l followed vour m,ooss.
tons, while here in April Last ie6ss in 1ss.
pairing the kerosene emulsion. NJ
to emulsify with resin compound and
use arsenic acid in addition am
Rlaa mat your hopes in this wash are
verined. In every instance where
your proposed arsenic acid was added.
either to emulsified kerosene or resin
compound, there has been a comnlefe
determination of the scales.
AT first too much of the arsenic acid
was used, resulting in more or lesa
injury to trees treated, particularly I'd
in weak washes. -
The best results in preparing tha
emulsion were obtained by taking
one part OF the kerosene to one part
OF luke warm resin compound. Thus
obtained two gallons of emulsion in
less than three minutes, that did not
snow any trace of separation before
the end of twenty-four hours. The
result would have been not quite 40
good II the resin compound had been
used hot in emulsifying, and still less
SO II two parts of kerosene had bean
USED TO one OF resin compound; but
still this last will make a very good
emulsion it prepared properly, which
IS easily done. 1t has the good Quail
ity OF spreading instantly over the
leaves, ii sprayed with diluent, as
well as do soap washes. None of the
experiments ms de during dry weather
with this emulsion alone, i. 9. without
the additional arsenic acid. were an
effective. The evaporation
was very rapid, and in ten minutes
after the application no trace of the
wash could be seen.
In addition, l include results of
various experiments with resin. COM
pound. especially upon Aphide' which
1t affects admirably; and. at the same
time, wash can be prepared which
VIII destroy all aphids and not iniure
the larvae of syrphus flies, nor prevent
the parasites from Matching from the
infested aphids.
Experiment 17S-Kerosene emul-
sion 167, with arsenic acid, of which
one pound in 55 gallons wash. Emul-
sion one part; water fifteen parts.
applied August 80, on A. Rapax on
pear: September l, leaves spotted.
turning brown. September 4, ali
leaves dead and dry; bark not in
Jured. except on few smallest twips:
scales all killed. October Z, tree
bringing forth new shoots all over:
some in blossom; all buds not dead
growing. November %, new shoots
OF eight inches in length had formed;
fruit did not set; tree in good condi-
lion, still growing. December IL. tree
fresh and green; no scales whatever.
Experiment 179-Kerosene 167 with
arsenic acid, of which one pound to
52% gallons wash. Emulsion one
part; water twenty parts. Applied
August 80, on Aspidiotus SD. on cur
rant, and A. rapax on cherry. Sep
tember Z, leaves nearly dry and fall
ing off; scales appear to be desd, but
still have their natural color. Octo-
Der z, all scales and eggs dead;
young shoots forming on currant.
November %, currant plant still grow
ing; some blossoms and Young fruit:
do scales. December II, no scales; q
few of the berries have become ma
ture, but are small.
Experiment 180-Kerosene emul-
sion with arsenic acid, Of which one
pound to IS gallons wash. Emulsion
one part; water two parts. Applied
August 30, on Aspidiotus So. on cur
rant, A. rapax and M. pomorum on
apple. September z, scales on cur
rant where in thick layers not all
dead; few eggs and newly Matched
young found; A. rapax on apple not
all dead gravid females and eggs of
NJ. pomorum not affected; leaves of
apple dry, and those on currant nearly
go. October 7, scales ON currant all
dry plant growing; A. rapax on apple
all dead eggs Of M. pomorum in good
condition. November %, no living
scal,s on currant, this still growing;
eggs of M. pomorum still intact.
Experiment 181.-Kerorene emul-
165 with arsenic, acid of which l
pound in IS gallons wash. Emulsion
one part; water fifteen parts. Applied
August 80 on aspidiotus sp. on cur
rant. September Z, leaves Of plan all
dry; few of the scales still living;
also eggs and newly Matched young
found. October Z, all scales dead;
plant in good condition. November
%, no living scales can be found.
December II, no living scales on
plant.
EXPERIMENTS WITH RESIN COMPOUND
AND ARSENIC ACID.
Experiment 1S5-Resin COM
pound and arsenic acid, OF which one
pound in So gallons wash. Com
pound one part; water 16 parts. APP
piled September 2, on locdnium hespe-
ridum on orange. All orange trees
on were in poor condi-
ton, received no water during summer
and leaves were curled. Sept. Z, most
of the young and tender shoots de-
stroyed, a few leaves falling; scales
appear to be dead. September ID,
scales all dead; leaves still falling,
only few remaining on tree. Novem-
ber %, no living scales; tree growing,
full of young shoots, but very few Of
the old leaves remaining. December
II, found four young scales which
evidently have come from neighbor-
ing trees; tree in good condition
again, still growing.
Experiment 186.-Rosin compound
and arsenic acid of which
poundl in 80 gallons wash. Com
pound one part; water eight parts.
Applied September 2, on L. hes
peridum on orange. September
Z, scales dead, found a. few
living young under mother scale;
few leaves falling. September 13, all
scales dead about half of the leaves
have fallen. October Z, no living
scales. November %, ABOUT one
third Of the leaves remaining; tree
otherwise in good condition. Decem-
ber II, tree in good condition; no live
ing scales.
Ex,or;,ooo< 1Qv- -Daesc ooxo,>o,.-.<l