The Logan Republican. [volume] (Logan, Utah) 1902-1924, 1915-09-11
Arseniica| Sprays
effectiveness Of Spraying Mixtures
Demonstrated by Field and La
boratory Experiments

Extensive field and laboratory
/ tests with different arsenicals in
killing chewing insects which attack
apple and certain other fruit trees
we're made during 1912, 1913 and 1914
by three entomologists of the depart
ment. These tests included labora-
| tory and field experiments in killing
the cooling moth, the larvae of the
| fall webworm, the larvae of the tent
caterpillar, the larvae of the tussock
moth and of a certain tiger moth and
the Datana. In addition to testing
straight arsenicals, a number of COM
pounds and combination sprays also
were used both to determine their eff
/ fectiveness and if possible to find
out what combinations were not sue
cessful because the several ingredi.
ents in them were incompatible and
formed insoluble products which were
either inert or damaged foliage or
did other harm. Especial attention
was given to the combination of fun
gicides and certain aphidicides with
arsenates, since the prevention Of
! fungus diseases and aphides Is init
mately associated with controlling the
chewing insects.
Following is brief summary Of
the results reached by the depart
ments specialists as reported in De-
partment Bulletin 27S, Miscellaneous
lnsecticide 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. effective
either in the paste or powdered form.
Triplumbic arsenate of lead is less
rapid as a poisoning agent than dip
lumbic arsenate, but is safer to use
on tender foliage.
Arsenate OF lead may be combined
with nicotine solutions and lime sui.
phur solution for the control of Ger.
tain apple chewing and sucking IN
sects and fungous diseases.
Fer the control Of certain sucking
and chewing insects arsenate of lead
may be combined with kerosene emul.
sion.
Arsenate Of lead kerosene emulsion
and lime sulphur is an incompatible
mixture, due to the formation Of an
insoluble calcium soap and the Sub,
sequent release of free kerosene. In
their experience any combination
containing lime sulphur and soar
should not be used, owing to the for
nation of an insoluble calcium soap
Arsenate of lead should not be mix
ed with sodium sulphid compounds
since the soluble sodium arsenatC
formed is destructive to leaf tissue
Arenate of lead combined with q
commercial barium tetrasulphid gave
satisfactory control of the codling
moth and caused no foliage injury in
the experimental apple orchard.
The most promising new insectIcidC
developed during the course OF the
experimental work is arsenate OF cal
cium. This arsenical may be manu-
featured at a cheaper cost than ar
senate of lead or may be readily
prepared at home. During the sea
sons OF 1919 and 1913 arsenate O
calcium gave encouraging results. II
1914 a commercial arsCnate of calci
UNI paste in combination with lime
sulphur gave very satisfactory contro
Of the cooling moth. While arsenatC
of calcium may have certain limita
tons, it will doubtless prove of val
ue for the control OF chewing insect.
on certain host plants.
Arsenate Of iron and arsenate Of
zinc are not as satisfactory as ARISEN
ate Of lead.
Arsenic compounds are dangerous
to use on tender foliage. In some I'm
stances, however, it may be possible
to prevent the soluble arsenic with
lime,
Sodium and potassium sulphur com
pounds gave fairly satisfactory con
troll Of the San Jose scale in some I'm.
stances equaling lime sulphur soIu.
ton. They may readily be prepared
at home without the use Of heat.
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