Wausau pilot. [volume] (Wausau, Wis.) 1896-1940, 1908-10-13

the green bug"-a species Of plant
louise which did enormous mischief In
the Southwest last year. In as much
as this insect begins its work in the
South, gradually extending its opera
tons porthward with the advance OF
the season, it seemed practicable to
collect great numbers of specimens of
its principal enemy in the Southern
fields. and, by throwing them in adj
vance Of the pest, to head 1t off, so
to speak. The attempt, however, was
not successful, nature evidently pre-
ferring her own methods.
The Green Bugs Enemy.
The enemy referred to is a very
minute four-winged fly, called Lysiple-
bus. Crawling over an infested plant.
it lays an egg in the body Of each
green bug it meets. The eggs thus
deposited quickly hatch, and the larvae
feed upon the vitals of the victims, pre-
venting them from breeding, and fin
ally killing them. At the end of ten
days they cut their way out and ap-
pear as flies, ready to start the per-
formance over again by laying their
own eggs in more green bugs. By this
means the pest is soon disposed of. A
plague Of green bugs (such as occurred
last year in Texas and Oklahoma, do
ing $2O,0O00OO worth of damage to
wheat and oats) arrives only when a
cold spring follows a mild winter. I'm
der such conditions great numbers Of
the bugs live over the winter, multi
plying continuously, while their little
foes, which cannot breed when the
temperature is below Sc degrees, do
not have chance to get in their work
until the season is far advanced.
The army worm Ito cite another ex-
ample In point) is a naked striped
caterpillar an inch and a quarter long
which makes its appearance in early
summer, devouring grains and grasses.
1t climbs the seed stalks and cuts off
the heads. Under favorable conditions
1t multiplies in fabulous numbers, and,
migrating in search Of food, travels
and feeds both day and night, infiict-
ing enormous damage. The crops
quickly disappear before the march of
its Unsuitable legions. Eventually,
when full fed, it burrows into the
ground, from which it energies later as
large brown miller.
Foes of the Army Worm. Il
Now, anybody who goes about in a
field that is being devastated by these
worms will notice that many, and even
a majority Of them have small white
spots on their bodies. These are the
eggs of little fly that looks somewhat
like a housefy, and which is known
to science as Winthemia. When they
are Matched the grubs that emerge from
them will bore through the skins of
the caterpillars and feed on their vi
tails. This will not prevent the worms
from doing damage, but it will render
them incapable of Transforming into
the adult form-of becoming moths, in
other words. Only those individuals
which escape attack by the parasite
will survive to perpetuate their species
the result being that the pest is so
nearly exterminated thar several years
usually elapse before it again occurs in
sufficient numbers to make serious
trouble.
After the caterpillars have disap-
peared from an infested field, ore who
visits 1t will find there great numbers
Of the little flies, buzzing and droning
like a swarm Of bees. Their presence
affords the best possible guarantee that
there will be no renewal of the plague
during the following season. What
happens under such conditions Is made
manifest if one takes the trouble to
collect a quantity of the worms and
put them into box covered with wire
net. It will be found that many flies
are reared, but almost no millers.
This is very new country, especial
ly in the agricultural sense, and ma
lures balance has been thrown tenn
porarily out Of gear, so to speak, by
mans interference.
Like a Fire Department.
In the Year Book of the Department
Of Agriculture will be found an ex-
tended discussion of this interesting
subject, from the pen of one Of the ex-
perts Of the Bureau of Insects, Mr. F.
NJ. Webster, to whom the writer is in
debted for his material. He compares
the working Of parasitism In the in
sect kingdom to that of a weIl-organ-
lied fire department in a large city.
There always have been, he says, and
probably always will be, occasional dis
astrous CONGREGATIONS in such cities,
but this fact does not In the least de-
tract from the value Of a fire service
In extinouishing thonsands Of COM