Askov American. [volume] (Askov, Pine County, Minn.) 1914-current, 1916-01-27
NEW tNSECTICiDE.
Arsenate OF Calcium Effective Against
Chewing insects on Fruit Trees.

Chewing insects on Fruit Trees.
Prepared by United States department Of
agricultural
AZ result of extensive tests with
different Insecticides the entomoiogists
Of the department have found that
calcium afsenate, a new insecticide,
gives very promising results In the
control Of certain insects that do dam
age by chewing GA fruit trees. Among
the chewing insects against which the
arsenate Of calcium proved effective
I'M laboratory and field tests conducted
at Benton Harbor. Mich. are the cod
ling moth. the fall webworm. the tent
caterpillar and the tussock moth
In these tests the effects of arsenate
Of calcium, both alone and combined
with lime sulphur solution were test
ed In comparison with arsenate of
lead alone and In combination with
lime sulphur. The arsenate of calcium.
as was the arsenate of lead, was used
at the rate Of two pounds to- each fifty
gallons Of water. In all the expert
ments the arsenate of calcium gave
very satisfactory results In killing the
larvae without burning the foliage. In
q number of cases It's killing action
was somewhat slower than. but com
pared favorably with, the arsenate of
lead. Since 1t can be produced more
cheaply than the lead arscnnte 1t would
appear to have distinct value. although
1t has not been sufficiently tested to
permit recommending It unrescrvediy
for general use. Where arsenate OF
calcium was combined with lime-sul-
phur 1T was. as a rule. even more eff
fective as poisoning agent than when
used alone and did not lessen the value
of the latter as fungicide. When
these compounds are combined the
amount Of foliage consumed by the
larvae il less than where the arsenate
Of calcium Is used alone. In tests In
1914 commercial arsenate Of calcium
tpastep. arsenic oxide 1882 per cent.
with lime-snlphur solution gave very
excellent control of the codling moth
In comparison with arsenate of lead
and with unsprayed plats. Where
arsenate of calcium was used 9S.19
per cent OF the apples were sound;
arsenate of lead showed OLA per cent
Of sound apples. while in the unspray
ed test platss only 58.7l per cent of the
apples were free from damage.
The following will be found to be q
convenient way of making homemade
arsenate Of calcium:
Stone lime coo per cent CaOl........ibs., So
Sodium arsenate, fused dry powderedt.
65 per cent AS s....................lbs lbs. 100
water ACKNOWLEDGEMENTS. .Bai 20
Place the stone lime In wooden con
tainer and add n small amount Of wa
ter. just enough to start stacking
When Stacking Is we'll under way pour
in the sodium arsenate. which should
first have been dissolved in hot water
Keep stirring until the lime has thor.
oughly slaked. Sufficient water should
he added from time TO time to prevent
burning.
The resulting arsenate of calcium
| should contain about Is per cent of ar.
senic oxide. In making this compound
1t will. OF course, be necessary to know
approximately the calcium oxide and
arsenic oxide content of the materials
employed and to vary the formula ac-
cordingly The byproGuct is largely so,
dunn hydroNide, which should he de
| canted IL the lnsecticide Is to be used
| nn tender foliage.