Montgomery County sentinel. [volume] (Rockville, Md.) 1855-1974, 1919-01-31
A New Corn Pest From Europe.
BY R. H. ALLEN.
From The Country Gentleman.

From The Country Gentleman.
The European corn borer-Pyrausia nu-
bilalis which has recently made its ap-
pearance in Massachusetts, seems to be
one of the most serious of insect pests ever
brought into this country. 1t appeared in
Massachusetts few years ago and is now
firmly established in thirty-four townships
west of Boston. 1t is difficult to ascertain
how or on what plant this insect was i'm
ported. In Central Europe and parts Of
Asia where the bOrer thrives, its food plants
are chiefly corn, millet. hops and hemp
and it often damages fifty per cent of the
crop. Perhaps a shipment of hemp to
some cordage company was responsible
for its introduction into this country.
The insect passes the winter as a cater
pillar in the stalks of corn, weeds or any
plant that affords slight protection. About
the middle Of May the caterpillar pupates,
still remaining inside the stem or stalk
where it hibernated The moth energies
from the pupa in about two weeks, and
lays as many as 700 eggs. These are de-
posted on the stems and leaves of the
early corn and weeds.
The caterpillars from these eggs feed
slightly on the surface, then burrow into
the tissues of the host plant, gradually
reaching the larger stems as they increase
in size. About the last of July these cat
erpillars finish their feeding, pupate, and
early in August the second generation of
moths appears. These lay their eggs. this
time as many as 900. which upon hatch
ing do vast amount of damage.
At this time the late corn is severely
attacked. the moth laying her eggs on all
parts Of the plant, tassel, ear. leaf and
stalk. These. in as the first generation, inn
medlately burrow in, and those entering
the tassel weaken it so that the wind soon
breaks it over. Those attacking the ear
render it unfit for eating and finally those
in the stalk riddle 1t tosuch an extent that
the plant collapses. Twenty per cent OF
the early corn was ruined last summer
and in some cases one hundred per cent
Of the late corn was destroyed. In hun
dreds Of war gardens hardly an ear was
picked that had not been attacked by the
borer. In parts of the affected district corn
was so badly infested that fifteen borers
were taken from single ear and 81 b0rers
from hill. From the middle of May uI
to cold weather one borer has been respon-
sible for $4,000. What would happen tC
our great corn crop If this pest should reach
the Corn Belt and increase as ii has
The name European corn borer" is per
haps misleading, as it might cause one t.
believe that the bOrer attacks only corn
Undoubtedly it prefers corn. but oats, pep
pers, celery, beets. spinach, Swiss chard
potatoes, tomatoes and beans are few
Of the garden crops recently found infested
Also it thrives in barnyard and foxtail grass
pigweed. ragweed, lamb's-quarters. ant
even the common burdock; also in sucl
Towering plants as dahlas. cosmos, sun
flowers and eeraniums.
The infestations Of many insects ar,
Immediately visible, either during the
feeding period or during Information. bu
not so with the borer, which presents diff
culties which are greater than those o
any other garden pest There is grea
danger from the European corn borer will
its two generations. its habit Of alway'
feeding inside. where il is impossible t
control it by spraying, and its unlimited
supply Of food plants-the only require
ment seeming to be stem large enouel
TO inclose the larv@.
Early last spring the borers we're fount
in corn stubble. the stalks having been Gu
the previous fall. Strange to say tn,
severe winter had apparently had no effec
on them. This stubble was plowed in
according to the usual custom, and at thu
same time a few infested butts were buriet
at various depths, to learn the effect or
the borer. II was found that stubble GOV
cred with twelve inches Of soil proved 4
offer little IL any resistance. for within {
few hours the bOrers had worked their way
TO the surface and were crawling toward
new food plants. About the middle Of the
summer a field Of barnyard grass was lyine
fiat. every plant so badly infested anC
weakened that it could not stand Oats
are of similar nature Of growth. VIVA
IL the European corn borer is allowed t.
reach localities where oats are grown2
| II is interesting to note that the aret
infested by the corn borer closely com
parGs with that of the gypsy moth in 1900
Last spring the area infested by the Euro.
pean corn borer covered 100 square miles
today 1t covers $40 square miles. Besides
the flight of the moth, there is the dan
ger of its being carried by automobiles
together with the possibility that II i
present in some other parts Of the coun
try, as yet undiscovered.
| As the borer passes the winter in thu
stalks or stems Of plants, we are afforded
an opportunity to combat it by pulling ~
and burning all cornstalks, weeds and gar
den rubbish. Every backyard garden. every
field and roadside. must be cleaned. This
would be an enormous undertaking pic.
ture removing all the weeds in an area
| $40 miles square. Even the ragweed and
pigweed alone would seem like an almost
impossible job; yet II appears to be only
a question Of whether we shall stamp thit
pest out now while it is in a relatively
small area. or allow il to spread over q
large section. making the problem more
difficult and causing thousands Of dollars
worth Of damage.