McNairy County independent. (Selmer, McNairy County, Tenn.) 1902-1969, 1922-02-03
TALKS TG FARMERS
THos +. PECK, Commissioner ofagriculture
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Economic Entomology
l. .lI.a. i.

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In earlier days entomology was
looked upon as a pastime for the
spare moments of those who cared
to turn their attention to it or as
a business $ confined to dusty
museums, without any practical
application whatever; the true
significance of the study was not
then apparent.
Gradually the practical side
developed and has since continued
to develop until at the present
time economic entomology is rec
ognized by agricultnrists as an
important adjunct to the study
of the actual crop production.
1t has been estimated that on
the average ten per cent of every
crop is a total less due to the
ravages of insect pests. A large
part of this, damage is so con-
stant, is produced by insects 80
inconspicuous or hidden, so scat
tered over large areas or various
seasons, that the agriculturist
may not know of it's existence,
or at any rate, does not figure it
other than as a perfectly normal
factor in crop production.
On the other hand, there are
pests like the locusts in the Phil
ipines, like the chinch bug of the
grain belt of the United States,
like the tse-tse fly of Africa,
whose depredations are so mark
ed that it is impossible not to rec
ognize them for what they are.
Midway between these two ex-
tremes is a vast assemblage of
insect pests, some sporadic or
local in their outbreaks, but all
of them injurious or capable of
becoming injurious. 1t is with
all of these, including both ex-
tremes, that economic entomology
has to deal, as well as with other
insects forms which, although
not pests, are yet of practical
Importance.
The problem is a large one.
The number of different species
of insects has been placed at
somewhat approaching two mil
lion. Many of these are very re-
stricted in their habitat; some of
them are cosmopolitan. They
must be classified and named, for
in the knowledge Of the relation
ships Of animals very often comes
a clue to the best manner of
combating them.
Exhaustive studies in the lab
oratory and field with parasites
and predaceous enemies, studies
frequently requiring inyestiga-
tons carried around the world,
must be made to determine what
natural checks may work upon
the pest. The results of meteor
illogical changes to insect life
must be understood. Chemicals
must be tried out to find their ef-
fectiveness as insect sprays, and
the possibilities of cultural meth
ods or farm practice for the con-
troll of pests most studied. FL
nally the results of all this work
must be arranged, tabulated,
weighed and put before the pub
lie.
In 1868 there was introduced
into California upon some trees
imported from a foreign country,
a species of scale insect which
spread itself over the State and
twenty years later was so pre-
valent and abundant that it
threatened to destroy the citrus
industry of that region. 1t was
learned that the scale was a ma
tive of Australia and that in Aus
tralia a certain ladybird beetle
was active in suppressing it.
Some of these beetles were in
troduced, bred and distributed
throughout the citrus groves of
the State and so efficiently did