The Canon City record with which is consolidated the Canon City cannon., 1912-07-11
ARSENITE OF
ZINC A new
INSECTICIDE

Ft. Collins, July 5.-Aresni,e of zinc
promises to afford orchardists a new
and better weapon with which to fight
insect pests which have proved invui-
nerable to other insecticides. This Is
the opinion OF George p. Weldon, dep
uty state entomologist at TIE agri-
cultural college here. Prof. Weldon
has just issued the following bulls-
tin:
"In the'fght against the great horde
OF chewing insects the various arsen-
ical sprays play an important part,
Among this class of sprays may be
mentioned Paris Green. london pur-
pie. arsenate Of lead. arsenate of iron.
arsenite OF zinc and sulphate arsenic.
Each one or these Insecticides is de-
pendaat largely upon the arsenic con-
tent for its value as an insect de-
stroyer
'In the above list only two kinds
are mentioned that are at all general
Iy used at the present time, viz: Paris
green and arsenate OF lead. While
these two arsenlcals must be recog-
nized as exceedingls valuable. they
have their weak points and are not So
good that something better cannot be
found to take their places.
zone OF the new and promising ar
senical sprays is arsenite Of zinc This
product was first manufactured by the
California spray-Chemieal company Of
watsonvIile. Cal. At the present time
other companies are experimenting
with 1t in order TO know how II may
best be made in order that they may
be able to supply the demand DO IL
proves the success at present indicat-
cd
The writer had occasion to expert
ment with this product in a western
slope orchard last season. In spraying
for the control OF the codling moth;
also to make observations where it
was used In score OF different
orchards.
"As a poison it seems to be slightly
more effective than arsenate Of lead.
There are those wa3 used Il last sea-
son who feel tina. controlled codling
moth much bette. and no one seems
to dot bt hut that 4 is at least as good
as the latter product
Prof :. a. Johnson in experiments
for tie control o. the bean lady bird
beetle. found that arsenatc OF zinc
would poison the beetles readily when
arsenate Of lead used very strong had
no apparent effect on them.
Unfortunately. considerable burning
of foliage and fruit was noted in GER
tain orchards sprayed with this pro-
duct least season, but II could not re-
ceive more severe criticism from this
standpoint than arsenate of lead. for
the latter also burned in certain or
chards. It seems true that when
spraying with either OF these products
Immediately procedes a shower OF rain
more or less burning OF foliage and
possibly fruit will result Last season
the weather was very showery n
western Colorado at the time when
the first and second applications for
I codling- moth were being made. and
no doubt the burning from both 4
these arsenic sprays should be attri-
buted TO that fact
From the limited amount OF work
done with arsenite of zinc. II would
not be we'll to recommend Its use in
place OF the long-used and reliable
arsenate OF lead. II seems well. how
ever, TO suggest that fruit growers at
least give some OF this material a
proper trial where II is possible TO
procure It. and especially upon Insects
that are more or less resistant TO the
poisoning effects OF lead arsenate.
I'VE cannot AFFORD TO say that ar