The Monmouth inquirer. [volume] (Freehold, N.J.) 1865-1933, 1924-09-04
ARsENIcAL SPRAYS.
Effectiveness Of Spraying Mixtures
Demonstrates by Field and Lab
nratorv Experiments.

Demonstrates by Field and Lab
oratory Experiments.
Extensive field and laboratory tests
with different arsenicals in killing
chewing insects which attack apple
and certain other fruit trees were made
by the entomologists Of the govern
ment agricultural department. These
tests included laboratory and field ex-
periments in killing the codltng moth,
the larvae Of the fall webworm. the
larvae Of the tent caterpillar, the lar
vac Of the tussock moth and OF GER
tain tiger moth and the Datana. In
addition to testing straight arsenicais,
a number of compounds and combina-
tions sprays also were used both to
determine their effectiveness and II
possible to find out what combinations
were not successful because of sever
al ingredients in them were incompati-
BILE and formed insoluble products
which were either inert or damaged
foliage or did other harm. Especial
attention was given to the combina-
ton of fungicides and certain aphid-
dcides with arsenates, since the pre-
yention of fungous diseases and aph-
ides is intimately associated with con-
trolling the chewing insects.
Following is brief summary of the
results reached by the departments
specialists, as reported in Department
RuIletin 278. Miscellaneous Insecti-
eide Investigations.
Arsenate of lead proved to be the
most consistent and valuable stomach
poison tested, giving satisfactory re-
suits throughout the experimental
work.
Arsenate OF lead is equally effec-
tive either in the paste or powdered
form.
Triplumbic arsenate of lead is less
rapid as a poisoning agent than di-
plumbic arsenate, but is safer to use
on tender foliage.
Arsenate Of lead may be combined
with nicotine solutions and lime-sCl-
phur solution for the control Of GER
tain apple chewing and sucking in
sects and fungous diseases,
For the control of certain sucking
and chewing insects arsenate of lead
may be combined with kerosene emul-
sion.
Arsenate of lead, kerosene emul-
sion, and lime-sulphur is an incom-
patible mixture, due to the formation
of an insoIuble calcium soap and the
subsequent release of free kerosene.
In theif experience any combination
containing Iine-sulphur and soap
should not be used. owing to the for
nation of an insoluble calcium soap.
Arsenate of lead should not be mix
ed with sodium sulphide compounds,
since the soluble sodium arsenate
formed is destructive to leaf tissue.
Arsenate of lead combined with
a commercial barium tetrasulphid
gave satisfactory control Of the cod
ding moth and caused no foliage In
jury in the experimental apple or
chard.
The most promising new insecticide
developed during the course OF the
experimental work is arsenate of cal
cium. This arsenical may be manu-
featured at a cheaper cost than arsen-
ate of lead or may be readily pre-
pared at home,
While arsenate of calcium may have
certain limitations, It win doubtless
prove of value for the control Of chew
ing insects on certain host plants.
Arsenate of iron and arsenate Of
zinc are not as satisfactory as arse
nate of lead.
Arsenate compounds are dangerous
to use on tender foliage. In some In
stances. however, it may be possible
to prevent foliage injury somewhat By
combining the soluble arsenic with the
lime.
Sodium and otassium-sulphur com
pounds gave fairly satisfactory con
troll of the San Jose scale, in some in
stances equaling lime-sulphur solu
ton. They may readily be prepared
at home without the use of heat.