Atlanta tri-weekly journal. [volume] (Atlanta, Ga.) 1920-19??, 1922-08-29

arsenite, magnesium arsenate, Lon
don purple and numerous other
trade mixtures of arsenica1s. In
view Of the present shortage, it is
going to be necessary and advisable
for the farmer to take practically
any one of these which can be Sc
cured, and any of them will accom-
plish satisfactory leaf worm con
troll. The only arsenicals which
would be avoided are the highly
soluble ones, such as sodium and
potassium arsenate and arsenite
which are very injurious to the
plants. The following outline GOV.
ers the manner in which these ma.
terials should be used:
Calcium arsenate should be ap.
piled at the rate of about three to
four pounds per acre. either
straight or diluted with one part OF
lime.
Lead arsenate should be applied
without dilution at the rate of four
TO five pounds per acre.
Paris green should always be mix
ed in the following proportions: /
part Paris green, part flour, and
from 1 to parts Of lime. The flour
will make the mixture stick to the
plant and the lime will reduce the
chance of plant injury. The mix
ture should be used at such rate
that about two pounds of Paris
green per acre will be applied.
London purple: should be used in
the same manner as Paris green.
Magnesium arsenate should be
9 Y$0i oh
OF lime, at the rate of about 5
pounds Of poison per acre.
Zinc arsenite should be used with
one part Of lime and applied at the
rate Of about four pounds per acre
of the poison.
The other miscellaneous arsenicals
generally contain some soluble
arsenic, and it is better to use them
with the addition of one or more
parts Of lime, as a safeguard against
plant injury.
The old standard method for treat
ing the cotton leaf worm is the "bag
and pole" with which everyone is
familiar, and this is still good when
other equipment is not available.
Practically all of these chemicals
can be applied with the bag and
pole, but it should be remembered
that such chemicals as lead arsenate,
calcium arsenate, etc., are of a more
sticky nature than Paris green, an d.
consequently the bags for applying
these should be made of cloth of a
more open weave than those used
Tor Par1s green. In addition, any
standard cotton busting machine OF
n a 1-ilx So, l. Ill =
can be used for the leaf worm also.
In some districts supplies of liquid
sprayers are available, and the ma
jority of these chemicals can be
applied in the spray form with very
good success. Whenever possible.
busting should be done when the
air is calm and the plants are moist,
but in case of absolute emergency
fairly satisfactory results can be Sc
cured by busting throughout the day
especially If busting machinery is
available for use rather than the
bag and pole.
The present outbreak of the leaf
worm is in some localities complicat-
ed by an outbreak of the fall army
worm or grass worm Uaphygma
frug1perda). The presence of the lat
ter worm can usually be noted by
the fact that it has a tendency to
bore into bolls and squares, eating
large hole through the outside
and then practically following out
the interior. This worm is not quite
as susceptible to poisoning as the
lear worm, but present reports indi-
cate that the poisoning being done
Tor leaf worm control is also &C.
complishing a fair degree of sue
cess in controlling the grass worm.
This laboratory is attempting to
maintain as close a check as possible
on supplies or arsenicals, and this
information will be kept up to date.
owing to the shortage of such ma.
terials, anyone planning to poison
the worn: is advised to locate sup.
plies just as soon as possible after
the need. is evident, and when un-
able to locate, any nearby stocks
this laboratory will be glad to as
sist in any way possible in advising
of the nearest source of supplv,
Furthermore, this information can
frequently be secured from your
state entomologist.
Pecan Trees Attacked by Aphids
W.. D. S., Midtown, Ca,
writes: Will you please tell us
what the effect of aphids on Pc
can trees will be? Honey dew
Is quite prevalent in this part of
the state, and many pecan trees
are being visited by the honey
bees continually during the day.
light. Other vegetation is also
showing the saccharine exuda-
tion.. Will these insects be dis
astrous to our trees, and is it
likely to require spraying?
Pecan trees have never been seri-
ously affected by aphids within our
knowledge. Probably a wet season
such as we are experiencing this
year is especially favorable for the
development Of this pest. We think
1t only temporary, or passing in
festation, however. Should the
aphfds become very bad, you can de.
stroy them in one Of several ways.
They may be washed off the trees
by means Of heavy spray of water
directed against them. An ordinary
spray pump could be used for this
purpose. A strong solution of soap
suds will also control their depreda-
tons. Unless they spread and be-
come very numerous, I do not think
1t necessary for you to take any &C.
ton against them. In the event it
should appear to be necessary, we
suggest that you proceed in the
manner Indicated
AYnOnor tho which o1>