The Washington herald., 1922-03-02
SCIENTISTS SPY
UPON WEEVILS;
FORETELL DAMAGE
How EntomoIogists ,can
Warn Cotton Grower
Of Danger.
THURSDAY. MARCH 4 rszz.

THURSDAY. MARCH Z rszz
EntenoIogfcaI society sf w..l,.
ton. New National Museum pno-
fs. tonight o'clock. Notessnd
exhibitions of specimens.
How can the entonolo,4.t. =,
lne Delta Laboratory OF me Ru-
reau Of Entomology Of the Densrs
ment of Agriculture, Al Tsri,,I.k
La, tell now how heavy IN. shoIi
weevll infestation in the south ,rtii
De this YEAR, For a numher ~
years they have been makinr .
series cf studies TO serve an 49,.
ior predictions regarding ths go,
rest. Vi 'He
Their studies for the coming yea,
nave Just been completed and thew
Preoict that the emergence of n.
Sest from winter quarters will he
eight years. e'te past
me number OF boil we..,,.
emerging from hibernation esch
spring depends on two thInp.-,h.
number entering Information IN ths
tall' and the percentage OF thee
surViving. they say. Last f,II
the greater part Of the cotton he,
saw conditions which permitted an
unusually large number of weeyils
TO enter hibernation. The winter
Neather has generally been abnor.
maiiy mild 10 date. and the usual
perioa OF severe weather has passed
although there Is. Of course stJIl
bare chance Of temperatures low
enough to influence weeyfI spr.
yival.
Because OF this mild wea.he,
high rate OF weeviI survival MS.
TO be expected Recent RECORDS
nave more than verified this expec-
-ation- These records are made in
number of different wayt. bur
the most comparable criterion a.
the ngure based on the nunber ~
live weevIls found hfbernating In
spanish moss in certain selected
localities In Louisiana each wear
Recently over 5000 pounds OF Snan-
ish moss from fifteen different So
lected points representing the dif-
ferent types of alternating conii-
tons found In that district were
examined. This moss is carefully
examined and the number Of wee
wills. both alive and dead, noted.
From this the ratio OF both alive
and dead weevils per ton OF moss
shown that this affords a very fair
index to the emergence which MAJ
be expected. The live weevils pcr
ton of moss for the past eight
years were: 1915. 10: 1916, "a: 1917,
s: 1918. IL: 1919, 4: 1920, s.5; 1921,
%; 1929. I27.
From these figures n Is seen
that there are far more live weevils
per ton Of moss in sight now than
at any time since these records were
! started and only a very few dead
weevils. or course the records on
the presence OF dead weevils can
not be accepted as absolutely accur-
ate because il has been found that
many dead weevils fall out OF the
moss during the winter and are thus
lost. The most striking feature
however, is the fact that the records
for this year show more than five
times as many live weevils in hi
. bernation as I'm the highest preced,
: ing year since 1915"
These records are checked in
other ways. among the different
methods being a series Of cages To-
Gated near Tallulah. which are in
stalled with a known number Of live
weevils each fall, different types OF
shelter provided and the survival
mined in the spring The labora-
: tory has just completed an exami-
nation Of this series Of cages and
finds that these figures verify those
quoted in the moss examinations.
and show the percentage Of survival
1 to date TO be much higher than in
past years"
G In considering the significance
Of these findings. IL should be re-
membered that while they mean a
; very abnormally heavy emergence
, OF over-wintered weevils in the
, coming spring. they do not neces-
sarily mean that the weetil damage
: this season will be unusually great
a since il is possible that summer
weather conditions may be suffi-
ciently unfavorable to the weevils
to offset this heavy, early infesta-
tion, but the fact remains that the
farmers will start the cotton crop
under a tremendous handicap and
IL is going to require abnormal
weather to prevent abnormal weevil
damage"