The Union daily times. [volume] (Union, S.C.) 1918-current, 1922-07-05
Boil Weevil Abundance
Demands EARLY Poiobning

The number of overwintered boil
weevils this year is far greater than
usual, according to records on the
emergence of The insect from nearly
all of the cotton states, accumulated
by the Delta Laboratory of the Bureau,
of Entomology of the United States
Department of Agriculture, at Tallu-
lah, La. This situation was forecast
some months ago. In many districts
where accurate counts have been
made, there are now as many Wee
wills in the fields as are ordina. lily
present a month later, when the first
aummer-bred brood has started to ap
pear. With anything like norma
weather conditions this is going to
mean tremendously rapid increase i.
the weevil damage, and this will hav
an important bearing on the progra.
to be followed by those using calcium
arsenate for the control of the weevil
Ordinarily the department recon-
mends starting poisoning when from
| lG to Is per cent of the cotton square;
have been punctured by the weevil. AS
general rule this condition does not
arise until after the newly-bred wee.
wills have started to emerge from the
squares. This year, however, man.
fields have been found where thers
are already sufficient weevils presen
to destroy practically all squares as.
fast as formed. In other words, such
cotton will never start blooming un-
less the wevils are controlled, and
from the very outset so per cent or
more of the squares are punctured. Ii
is necessary to poison earlier than
ever before. There is no advantage in
poisoning the cotton before the
squares form, as the weevils are con =.
tinuing to emerge from Information
during this period and furthermore
they are doing the crop no harm.
Where a heavy infestation occurs H.
will be advisable 20 make the first
application just as soon as the cotton
starts squaring freely, or about the
time the plants average from a to 5
squares each. The regular poisoning
schedule should be started at thar
time and continued along the lines Of
| the usual recommendation for con-
| trolling this early infestation of wee
| wills.
Another very important effect of
this heavy infestation will be felt
later in the season. When the weevils
first emerge from Information they
move around very little as long as
they can find an ample supply of un-
punctured squares for their use, but
just as soon as the infestation be.
comes sufficiently heavy to puncture
practically all squares these weevils
start to move in search of fresh pas
lures. In an ordinary season this
means that farmer usually has only
the weevils bred in his own cotton
to contend with until sometime from
the latter part Of July to the end of
August, depending on the locality.
Migration of weevils will probably
start several weeks earlier this year
than usual; and, in addition to having
to control his own infestation earlier
by poisoning, the planter can expect
that before the fruit set during the
period of protection has had time to
mature there will be an immigration
of weevils from imprisoned cotton.
Every day large crop Of new weevi!s
will move into these poisoned fields
and it is going to take continuous.
thorough poisoning to protect to ma
turity the crop that has been allowed
to set by the earlier applications.
Successful weevil control this year
is going to require more effort and
more poison per acre than has ever
been the case in the past. On the 9TH
er hand, wherever the land is suf-
fciently fertile to Justify the effort.
the increase in cost per acre due to
the increased number of applications
of poison necessary will be more than
offset by the fact that weevil damage
without poisoning will be far create.
than normal and the margin of profit
on the successful crop is tremendously
increased.