Evening star. [volume] (Washington, D.C.) 1854-1972, 1962-12-07

our right to know" and If,
knowing, we have concluded
that we are being asked to take
senseless and frightening risks,
then we should no longer accept
the counsel of those who tell us
that we must fill our world
with poisonous chemicals; we
should look about and see what
other course is open to us.
A truly extraordinary variety
Of alternatives to the chemical
control Of insects is available.
Some are already in use and
have achieved brilliant success.
Others are in the stage Of lab
oratory testing. Still others are
little more than ideas in the
minds of imaginative scien-
fists, waiting for the opportu-
nifty to put them to the test.
All have this in common: They
are biological solutions, based
on understanding of the living
organisms they seek to con-
troll, and of the whole fabric
of life to which these organ
isms belong.
Specialists representing vari-
GUS areas of the vast field of
biology are contributing en-
tomologists, pathologists, ge-
neticists, PSYCHOLOGISTS, bio
chemists, biologists all pour
ing their knowledge and their
creative inspirations into the
formation Of a new science Of
biotic controls.
Some of the most fascinat-
ling of the new methods are
those that seek to turn the
strength of a species against
itself-to use the drive of an
insects life forces to destroy 1t.
The most spectacular Of these
approaches is the male sterili-
cation" technique developed by
the chief of the United States
Department Of Agriculture's
Entomology Research Branch,
DR.. Edward Knipling, and his
associates.
About a quarter of a century
ago DR.. Knipling startled his
colleagues by proposing q
unique method of insect con-
troll. If 1t were possible to steri-
lie and release large numbers
of insects, he theorized, the
sterilized males would. under
certain conditions, compete
with the normal wild males so
successfully that, after repeated
releases, only infertile eggs
would be produced and the pop
ulation would die out.
Test Plan Works
About 1850, DR.. Kniplng
launched a serious effort to
turn insect sterilization into a
weapon that would wipe out a
major insect enemy of live
stock in the South. the screw
worm fly.
Beginning in August, 1854,
screw-worms reared and Steri-
lized in an Agriculture Depart
ment laboratory in Florida
were flown to Curacao and re-
leased from airplanes at the
rate Of about 400 per square
mile per week. Almost at once
the number of egg masses de-
posted on experimental goats
began to decrease. as did their
fertility. Only seven weeks after
the releases were started, all
eggs were infertile. Soon it was
impossible to find a single egg
mass. sterile or otherwise. The
screw-worm had indeed been
eradicated on Curacao.
The resounding success Of the
Curacao experiment whetted
the appetites of Florida live
stock raisers for a similar feat
that would relieve them Of the
scourge of screw-worms. In
1857 the United States Depart
ment Of Agriculture and the
State of Florida joined in pro-
viding funds for an eradication
effort. The project involved the
weekly production Of about so
million screw-worms at a spe-
cially constructed "fly factory"
the use Of 20 light airplanes
TO fly pre-arranged flight pat
terms, five to six hours daily,
each plane carrying a thousand
paper cartons, each carton con-
tanning 200 to 400 irradiated
flies.
The cold winter Of 1878,
when freezing temperatures
gripped Northern Florida, gave
an unexpected opportunity to
start the program while the
screw-worm populations were
reduced and confined to q