The Sun. [volume] (Price, Utah) 1915-1932, 1920-10-01
Correspondence The sun.


Correspondence The sun
WASHINGTON. d. c.. Sept. 2s.-
Farmers in regions newly infested by
the alfalfa wruvil will be interested in
knowing that an unusui.iJ effective
method of control has been worked
out by the United States department
of agriculture. Specialists of the de-
pariment say that rarely has any
method Of insect control been 80
thoroughly safeguardcd against fail
uro as alfalfa weevil spraying. II has
been tested gyery season for seven
years The cost # the operation.
about dollar an acre-is trfling
compared with the returns, and no
farmer in the territory infested or
threatened can afford to overlook it,
the specialists say There is no con-
troll measure. however, which can be
applied advantageously this late in
the season. Effective work must be
delayed until next spring. Control is
had by spraying poison over the fields
va that Il will cover the growing parts
ON which the wecvils mostly feed
Arscnatc of lead aud arsenitc of zinc
have been mostly used, but other
arsenicals recommended for orchard
spraying are thought TO be about as
good. There is practically no danger
of burning the foliage of alfalfa and,
therefore, the range of suitable
poisons is larger than in fruit tree
spraying Arenate of lead Is said TO
be, everything considered, the best
poison TO use, principally because il
sticks 10 the leaves more readily and
a'osts less than most of the others. The
poison is weighed or measured Mt the
rate Of two pounds of powder or four
pounds Of commercial paste for each
hundred gallons of water, Is stirred
with little water In n pail until Il
becomes thin paste without Jumps
and is diluted and strained into the
sprayer tank. Two pounds Of laundry
soap for each gallon should be added
m order 10 make the liquid stick Ia
tho leaves properly. The dry, poWd
NANA ANAA W AA' lFNlHNh ~ HNAANN iNAt
the paste. There Is no danger of stool
being poisoned by hay cut from spray
ed fields where the poison is apple,
nt n rate not greater than q hundre,
gallons Of spray mixture per ncro.
Simple Outfit Sufficient.
The essentials of the spraying out
tit are q truck or other vehicle, tanl
with AN agitator 10 keep the poison
from settling 10 the bottom, q pump
"a pressure gungc, an engine an,
pumping jack unless the pump Is /,
be- driven By hand, a siraincr, pip,
Tor distributing the liquid from IA,
pump aud as many nozzles as are re
quired by the capacity of the pump
These essentials may all be eontaine'
IN a baTelpump outfit carried Ia
wagon. The pump must be capable %
delivering our-titlhs of a gallon %
more minute and maintaining
pressure of nt least seventy-fiy
pounds. II the pressure is less that
that the mist spray will not be fin
enough 10 prevent the liquid frou
gathering in drops and running 10 th
ground instead of drying ON the top
of the plants, The number of nozzle
used should be- sufficient to take al
the capacity of the pump At th
average walking gait of team, eacl
nozzle should deliver nine-tenths of
gallon q minute. Therefore, a puml
of nine gallons capacity per minute
will supply ten MOBILES, each of whicl
covers strip two feet wide, BY al
arithmetical calculation of the cubica
content of the pump cylinder and IN,
number of strokes per minute, IA,
capacity of the outfit can be detcrmin
ed. The spray should be applied a
the rate of a hundred gallons o
spray mixture per acre, Nearly an!
kind of spraying outfit can be adapt
ed for this purpose, However, modern
orchard spray outfits are usually de
signed Ia give "a comparatively SINAI
flow and high pressure and are les
suitable for alfalfa spraying than th'
older pumps with larger cylinders anC
stronger stroke designed for large
flow and lower pressure.
Keep Well StIrred.
The spraying outfit should b,
mounted ON the wagon or other vehicl,
used so that the nozzles will be abou
two feet above the tops of the alfalf'
plants. Four fifty-gallon barrels will
AN engine and pump mounted ON al
ordinary wagon or for a hand puml
an express wagon aud fewer barrel
constitute satisfactory outfit. 4
paddle, dasher or some other form o
agitator must be provided 10 keep tn
liquid stirred, A strainer Of twenty
mesh brass or bronze screen should b
fitted to the opening through whicl
the water enteres the tank and an
other over the outlet leading 10 TN
pump. The parts Of the pump il
which close fitting is required shout,
be of brass, bronze, porcelain or som
other substance less rapidly corrodel
by the chemicals than are iron an,
steel. All commercial spray pump
are built in this way, but pump