The Snowflake herald., 1922-08-18

and Work OF Larvae.
fit. paddle, daSner, or some other
form of agitator must be provided to
keep the liquid stirred. A strainer of
20-mesh brass or bronze screen should
be fitted to the opening through which
the water enters the tank and an
other over the outlet leading to the
pump. The parts of the pump in which
close fitting is required should be of
brass, bronze, porcelain, or some other
substance less rapidly cOrroded by the
chemicals than iron and steel. All
commercial spray pumps are built in
this way, but pumps which were in
tended for other purposes should be
refitted when used for spraying.
An engine driven outfit must have
a relief valve near the pump, permit
ting the surplus flow to return to the
tank. The pump must have an air
pressure chamber large enough to
keep the flow steady and insure even
distribution of the poison. Even pres
sure, indispensable for uniform spread
of the poison, cannot be maintained
without d pressure gauge. This
gauge should be attached to the pres
sure chamber or near it and at a dis
lance from relief-valve and nozzles.
The boom or pipe which carries the
MOBILES and supplies them with liquid
from the pump is made of two-foot
pieces of one-half inch galvanized IRON
pipe joined by Tvs, each of which af-
fords an opening for the attachment
or nozzle. The boom is cOnnected|
with the pump by a one-half inch
pr1ssure hose. The boom should bel
supported by Il piece Of timber, two by
four, clamped or hinged to the truck
with the boom stapled, bolted, orr
wired to it. Plain misty nozzles
without strainers or other compiled
tons, should be used.
Spray in Warm Weather.
! The best time for spraying is at
what the specialists call the turning
point of weevil infestation--from one
| to two weeks before the first crop is
! ready for cutting, when the young
larvae become so numerous that they
completely destroy the growing tips.
| After that point is reached the
weevils, if left alone, consume the
leaves until nothing is left but the
woody ffbers. If spraying is done
at this time the crop RECEIVERS quick
ly. Spraying yearly in the spring
! sometimes entirely prevents damage
but it is uncertain. On the other hand
| plants sprayed after they were en-
! tirely stripped of their foliage have
been able to recover and bloom, but
this allows destruction to go too far
and makes recovery too slow.
Spraying at the turning point not
only protects the first crop but con
fers an even larger benefit on the sec
ond crop, which sprouts and grows
without delay, and no treatment of
the stubble is necessary.
Stubble spraying, after the cutting
of the first crop, has been successfully
DONE but 1t requires getting into the
field Immediately after cutting and a
much larger quantity of liquid is re-
CURED than if 1t were applied to the
first crop. Stubble spraying, there
fore, is advised only when earlier
spraying has been impossible
Spraying should be done, if possible,
at the beginning of a warm SPELL The
weevils do not feed so voraciously in
cool weather.
! There are other control measures
but none of them promises much more
unless applied before or Immediately
oftor tho first c1ttinn Ono roo+bo1 Sc
to pasture the alfalfa field until most
of the eggs and young larvae have
been destroyed. Another is to use
the alfalfa as soiling crop, cutting
it green two or three times during the
season. These methods, however
must be practiced before the turning
point of infestation, as after that time
the weevils destroy the plants so COM
pletely that there Is not enough growth
for either pasture or soiling Another
method is to cultivate the field with
harrow or other implement, imme-
diately after the first cutting, in such
way as TO cover the field with dust
mulch, thus exposing the entire sur
face OF the field to the sun and kill
ing most of the weevils. In some in
stances. the second crop has been pro
tected by dragging the stubble, while
it is still wet from irrigation. with
/ the land leveler or the clOd breaker.
This causes the insects to perish by
embedding them in the mud, but it is
harmful to the soil and is not recon-
mended