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How to Fight the StrawberrySWeevil. By Entomologist Franklin Sherman.
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THE tJOGT LARQELY CIRCULATED FARM WEEKLY PUDLIGHED BETWEEN IV A OH I Ni ON AND NEW ORLEANS.
Vol. XIX. No. 20.
RALEIGH, N. C, TUESDAY, JUNE 28, 1904.
$1 a Year.
The Progressive Farmer.
CLARENCE H: POE,
B. W. KILOORB,
C W. BURKBTT, J
Editor and Manager.
TALKS ON INSECT PESTS.
XI. The Strawberry Weevil. '
Editors Progressive Farmer:
The work of this insect is familiar to the grow
ers in this .State through all the country from Mt.
Olive to Wilmington and from there west to
Chadbourn. It has been known as a pest in this
region for the past four or five years and seems
to be rapidly gaining in numbers and destructive
ness. It has at one time or another been de
structive in most of the eastern States, especially
north of North Carolina, and even in Canada
It is the mature! adult insect which does the
damage, and strange as it may seem, there are
growers right in the midst of the weevil district,
who have lost money from its ravages every year
for four or five years, who have never yet leaSmed
the insect sufficiently well to recognize it posi
tively. The adult beetle is a little larger than
the head of a good-sized pin and more elongated,
of course. It is of a chestnut-brown color, and
has on each side of the body a black spot which
is surrounded by a gray border. From ,the head
there projects a snout of a little more than one
half the length of the body. There are any num-
ber of other beetles of about the same size, but
the spots, one on each side of the middle of
the back, and the snout projecting from the head ;
these two points taken together with the chestnut-brown
color, will enable any intelligent, keen
eyed person to recognize it with certainty.
CHARACTER OF INJURY.
The injury by this insect consists in depositing
eggs within unopened buds, and then severing the
stalks so that the buds wilt and finally drop to
the ground. In this way, one female insect will
often destroy many buds.. We have counted as
high as eighty cut buds on a single hill.
During the strawberry season just closed, Mr.
R. W. Collett and the writer were able to make
quite extended observations on this insect our
principal field of operations being at Wallace, in
the very heart of the weevil district. We were
thus able to corroborate many points in the life
history of the insect which had been recorded be
fore, and added some original and valuable obser
vations of our own. Thorough knowledge of the
life-history and habits are essential to secure the
best results in combating this pest.
The adult weevils were first observed on March
31st and on April 4th, Mr. Collet found them
abundant, mating, laying eggs and cutting the
buds. On April 12th, we found that the eggs
were hatching to tiny, white, footless grubs inside
the now fallen buds. On June 5th, Mr. Collett
found that, the grubs were transforming to pupae
(still inside tlia buds), and that many of the pupae
had developed into adult beetles which had
emerged. At that date adults, pupae, and grown
larvae, were still abundant in the fields, although
the last picking of fruit had been some two weeks
previous. Here, then, had been two weeks when
the vines were useless, that the insects were
coming to maturity undisturbed. We will see later
what may be done at that time.
Although adults were numerous at Wallace on
June 5th, Mr. Collett did not find them mating,
but he did find many of them on the flowers of
certain wild plants in the woods, especially the
gall-berry. In fact, at that time the whole trend
of movement seemed to be from the strawberry
fields where the insects were maturing, to the
woods. There were no efforts being made to pro
vide for another generation, and this observation
is exactly in accord with those of other investiga
tors. Indeed, it seems pretty well established
now that there is only one annual generation of
the weevil, namely, those which reach maturity
immediately after the picking season. Therefore
the same adult weevils which Mr. Collett found
migrating to the woods on June 5th, will come
forth from their winter quarters next spring, to
cut the buds. - There is no time iirthe life of the
insect from the time that the egr is laid until
the adult emerges, that is spent outside the very
bud in which the eggs is laid. The larva (grub)
does not go from one bud to another, and there is
no time when it enters the ground. It is always
in that bud in which it hatches from the egg.
The principal food of the insect, both in the
beetle and grub state, is pollen, hence.it attacks
the pollen-bearing varieties (the "perfect bloom
ers") much more than the others. It so happens
that many of the most highly prized varieties are
perfect bloomers. The adult insect can fly freely,
although it seems seldom to do so ; the usual mode
Lof escape being to simply double up the legs and
roll, or drop, to the ground. It does not "jump"
as some have described to me. The adult beetles
may be found on a large number of flowers, but
they only seem to cut and deposit eggs in a few,
principal among which are the strawberry, black
berry, dewberry, red-bun, cinque-foil and rose. We
found the adult insects mating, depositing eggs
and cutting the buds of roses growing on the
porch of the Boney House, at Wallace, on April
WHERE DOES THE INSECT PASS THE WINTER?
As yet, it is impossible to say definijely just how
and where the insects hibernate. It seems certain
that they winter in the adult stage, and it also
seems certain that they hibernate around the
edges of the field or in the woods ; but exactly
where, whether in stumps, rotten logs, under trash,
rubbish and leaves, or under the surface of the
earth, remains a question. Two whole days of
careful search (on March 9th and 10th) under
bark; sifting dirt, trash, pine-straw, etc., failed
to throw any light on this question, for although
I found a considerable number of other insects, io
evidence of weevil was "to be found. From care
ful observation and search, I am convinced that
they are not brought into the fields in the pine
straw, for if that were the case they would ap
pear as soon and as abundantly in one part of
the field as the other. I have carefully sifted
over a good deal of the straw, both in the woods,
in the piles where it had been all winter, and in
the field after it had been distributed, without
finding any trace of the weevils. There is yet
opportunity for some enterprising grower to fill
this gap in our knowledge of the pest.
REMEDIES FOR THE PEST
In our work at Wallace, Mr. Collett made prac
tical applications of nine different treatments
on our little experimental plat on the place of
Mr. J. A. Westbrook. Among these we used
"spirittine," a preparation which has recently been
used against insects on truck crops. Other tests
were with air-slaked lime, bordeaux mixture and
paris green, carbolic acid in water, whale oil
soap in water and others. The plat was in one
side of a field of about thirty acres in which no
efforts were being made to keep the insects in
check. . Our experiments, therefore, had to be
along the line of securing an immediate result.
No treatment could be applied with a view of
would be open to invasion irom all the surround
ing fields. Our experiments demonstrated one
thing thoroughly- that there is, little or no hope
of ever securing any direct remedy. On all rows,
no matter what treatment was applied, the weevil
was seriously, and about equally, destructive.
Both carbolic acid solution and spirittine solution
were used at so great strength as to seriously
burn the foliage on , some plants, yet with ab-
soiuteiy no result on tne weevil. ne vines sprayeo
with bordeaux and paris green will no doubt be
benefited by protection from rust and other trou
bles, but the treatment did not mitigate the
weevil Lfury in the least. In previous years
others have tried various other treatments so ex-,
haustively that we did not feel it necessary to re
peat their work. Indeed, as a summary, we may
say that we see no hope of any material being
used as a spray or dust application which will
be of material benefit, and we are positive in, the
conviction that the best results will be secured
through the planting of other varieties, clean cul
ture of beds, the burning of trash, and especially
of ditch banks overgrown with dewberries, and
the piompt cleaning up of fields immediately af
ter the picking is over. Let us consider these
a little more in detail.
PLANTING OTHER VARITIES.
The insect attacks chiefly the stamminate va
rieties (those which bear pollen), although it is a
fact that they do attack the others to some ex
tent. The varieties at present most extensively
grown in the strawberry section are the (1) Ex
celsior, (2) Thompson, (3) Heflin, (4) McKinley,
(5) Duff, (6) Dixie Belle, and (7) Profit. Of these
the first .four are perfect bloomers; and hence
fully liable to attack. The last three are imper
fect bloomers, and hence not so much attacked.
T-f oaAtna trmirraai Kla r TiTnnnno art lmnprf
blooming berry which will mature fruit as early
as the perfect bloomers, for which reason those
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