Imperial Valley press., 1938-02-27

| Losses 10 American agriculture,
caused by plant pests and insects,
cost the farming industry more
than two billion dollars annually
as much as the United States
spends, in normal years, for it's
entire program of national defense
against foreign powers!
Consequently, any discovery prom
ising to make for more effective
and economical control measures,
with resultant reduction in farm
losses, is of immediate interest to
farmers.
And California's splendid corps of
research experts and scientific tech
nicians, constantly at work at the
problem, has repeatedly made i'm
portant contributions to the un-
ending battle against both plant
diseases and pests.
Latest to announce a discovery,
which he hopes will pave the way
for inexpensive and poisonous
methods of controlling pests and
insects is a University OF Califor-
mia scientists, j. K. Ellsworth, who
reports to the American Association
for the Advancement of Science
that he has learned insects are at
| tracted to certain colors, just as
men and women have color prefer
ences in clothes and decorations
BY making use OF their color
preferences, Ellsworth predicts it
will be possible to lure various kinds
of insects into traps where they will
be electrocuted-at small cost to the
farmer!
One of the major pests affecting
California fruit groWers-the grape
leaf f-hopper-will fly directly to a
pale blue light. for example, but is
not attracted to red or green, ac-
cording to the scientists report.
The California entomologiSt re-
ports that in conjunction with fell
low workers he used diStinctively
colored lights to trap leaf-hoppers
and many other insects. A system
of electric light tubes, using neon
and other gases which give a light
of one color, was devised and put
to test inside a cage, the bars OF
which were electrically charged.
He reports that the insects flew
toward the light of their particular
color preference and were electro
cuted as they touched the bars of
the cage.
AS many as 5000 insects were
found deal around each trap night
| ly, according to Ellsworth, who de-
clares that one trap per acre is suf-
ficient to control the insects.
And the cost of installing and
maintaining the traps amounts to
only So per acre for an entire sea-
son, his report indicates.
If the Ellsworth discovery works
out in practice as it has in tests,
it will undoubtedly be of tremendous
value in controlling plaques of grass
hoppers, chinch bugs, army worms,
moths, beetles and other insects.
Ellsworth predicts that the SyS-
tenn of lights, with electric cages,
will prove less expensive and
much more effective than poison
bats and costly spray materials.
The use of such traps, in lieu of
poisonous sprays, Ellsworth points
out, would also eliminate the costly
and tedious work of washing farm
products, as now required under
federal regulations to protect con-
SumerS.
AS Ellsworth notes in his report
to the Association for the Advance
ment Of Science, the use of candles
and bonfires to attract and kill in
sects is at least 200 years old.
But it has never before been cS-
tablished that monochromatic or
Single-color light could be used as
insect bait-With the color being
varied to fit the color preferences
and idiosyncrasies of individual
pests.
In addition to the value OF the
discovery to farmers-if it lives up
to expectations - Ellsworth also
stresses that the innovation may
have a definite value in combating
malaria and other human illnesses
transmitted by Insects
Agriculture owes very real debt
of gratitude to its men of science