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CONTROL OF
CANARY FLY
Correct Time For
Spraying
HOBART, Sunday.
The Minister for Agriculture
(Mr. T. D'Alton) said yesterday
ho had hoon advised by the de-
partment's entomologist (Dr. J. W.
Evans) that the history of the can-
ary fly, which had been established
in Tasmania for a number of years,
and appropriate measures for its
control h;>d been investigated by
tho department.
Information obtained had been made
available to orchardists, hut it appear-
ed that many wero not yet conversant
with the facts. The entomologist poin-
ted out that as the control was^largely
obtained through thc application of
nicotine-sulphate sprays, which were
costly, it was important at present that
wastage caused by faulty liming of
sprays should bo avoided.
METHOD OF CONTROL.
The canary fly bred and fed mainly
on apple and hawthorn trees, and some-
times to a lesser extent on pears, plums
and related trees aud shrubs, said Mr.
D'Alton. It never fed ou crasses or
on any low-growing plnnt. Insects
seen on such plants were not the can-
ary fly, and would never attack apple
trees. Tho winter was passed in tho
egg stage. There wero no means by
which tho eggs could be destroyed, and
winter sprays wero useless. Tho eggs
began to hatch at tho beginning of
?September, and hatching continued _un
til carly in November, at which timo
the first adults appeared. Female in-
sects did not lay eggs until about a
week niter they acquired their wings.
Tho time for tho first spray was during
tho first week in November, hence it
might bo convenient to combine tho
nicotino-sulphnto (ono pint in 75 gallons
of water) with lead arsenato Calyx
spray. If nicotine-sulphate wero ap-
plied by itself, soap (l'J ozs. of hard
soap to 75 gallons of water) should
be added to tho mixture. A second ap-
plication of tho samo naturo should
follow threo or four weeks lator to _ki|l
those insects which had hatched since
tho first application, If tho sprays
were applied at the right time on warm
days (when tho nicotiue-sulphato was
most effective) and a good covering
given to tho undersides of tho leaves
on which tho young insects congrega-
ted, it would not be necessary to spray
again for canary fly during the sea
son. .
Goori but. not quito ns satisfactory
control could bo ottained if limo sul-
phur -wore used, instead of uicotino sul
phato for tho first application. If this
were done, it was absolutely essential
that tho second application should bo
well timed and made ou a favorable '
day. - I
LATE SPRAYS.
If either of tlieso phases had been
neglected or improperly timed it was
probable that the insect would breed up
to tho new year. In this caí¡e nico
tino sulphate should bo applied at a
time when tho majority of insects woro
at tho young stage of second growth
and almost mature. Insects that were
almost full grown had a pair of small
wings sloping down each side of the
body. In most seasons the ead of Jan-
uary was tho correct timo to apply the
sprays for the second generation, but
as tho present season was lato, it was
probablo that tho majority of the in-
sects would not be full grown till tho
first fortnight in February. A watch
should bc hopt at that fimo, and as
soon ns a few insects were flying near
thc fruit thc spray should be iippliod.
lt could not, bo too strongly stressed
that it was a waste of time of time and
money to spray trees for canary fly
when tho majority of the insects wore
nt the winged stage, or nt such time
ns tho present, when they wero mostly
I in tho egg stage.
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