The Redwood gazette. [volume] (Redwood Falls, Minn.) 1873-1940, 1880-07-15
lhe Terrible Army Worm.

1Ae Terrible Army Worm.
The destructive insect which has
been devastating the grass and grain
fields for weeks along the Atlantic sea-
board is not new visitor, but has been
known in this country ut least since
-1743. The " army worm" Is the cater.
pillar Of the LescaniG nnipsxncta, ono
Of the family Of night-flying moths: The
moth is Of rusty grayish GENEROUS
brown Or buff color, with wings free
from the usual markings, but having q
conspicuous white dot near the middle
of each Of the front wings. The worm
is about an inch and.a half long, and re-
sembles tho cut-worm in shape. 1t is
dark in color, with light, interrupted,
threadlike line along the middle Of the
back. and light lines along the sides
and just above the legs. The name
"army worm is derived from the reg
ular, trained way in which myriads Of
them march together side by side, in
long, wide columns, as they pass from
field to field in search of food. It is
quite different from its equally-de-
structive namesake, the army or cotton
worm of the South.
Usually the numbers Of these cater
pillars are inconsiderable. But they ap-
peared In vast numbers In New York
and New England in the years 1743,
ITO, 1890, and 1917. In some of the
Western States they have been very
destructive several times during the
present century, and in 1861 caused
great havoc in the Eastern States. The
present season they began their depre-
dations in winter, and did considerable
damage to winter grain in December,
January and February in localities as
far north as Union County, South Caro-.
lima, and Marion County, Tennessee.
The moth lays her eggs in the folds
of leaves of grass or grain, generally
concealing them from sight by pushing
Thorn down in the embodied part of the
leaf, or by cementing the edges of the
leaf together over them. The number
of eggs deposited is usually fifteen or
twenty. Prof. Riley saws there is but
one generation annually; other author
ties state that in the Middle and West
ern States the eggs are probably de-
posted for q first brood in April and
May, and in June and July for a second
brood. Farther north, as in New En-
gland, the moth appears in October,
and probably then lays her eggs,
which do not hatch till spring. Prof.
Comstock, the Entomclogist of the
Agricultural Department, asserts that
the number of generations varies great
ly with the climate, ard that during
winters of unusual mildness a success
ion of broods is kept up through the
entire year. Concerning the hiberna-
ton of the worm, as to which writer's
have long differed, Prof. Comstock says
it can now be safely stated that it
chrysalis state. In either case, as soon
as the weather becomes warm in the
spring, the moths emerge from their
pupal cases or their alternating quar-
tiers, and lay their eggs. The worms are
Matched in from eight to ten days.
In dealing with this insect, prevent
i've measures are best. On this point
Prof. Comstock says in a recent report
to the Agricultural Department.:
''The best means of preventing the
occurrence of this pest in cultivated
fields will be to keep watch of any ex-
tensive tracts of low land which may be
in the neighborhood, and If army
worms are discovered, destroy them
either by burning over the land, if posi-
BILE, or by poisoning with arsenic, Paris
green, or London purple, OF by any
other means of which the local condi-
tions will admit. It would be well to
burn over all the low lands in the vi
cinity each winter, thus destroying the
alternating insects. In case the worms
do appear in cultivated lands, the best
plan of action to follow is to prevent
the spreading of the insect. This may,
be done by destroying them, or by con-
fining them to the fields in which they
appear. The best method of destroy
ing. thon, ia by crushing with rollers or
by poisoning with arsenic, Paris green,
or London purple. Either of these SUBJ
stances can be applied rapidly by mix.
ing with water and using fountain
pump or garden syringe. The second
line Of defense is by means of bitches
and pits dug around the infested field
or that to be protected. The bitches
can be made quite rapidly. First plow
a furrow with the land side next to
the field to be protected, and then with
a spade make this side of the furrow
vertical, or if the soil be compact
enough to admit of it, overhanging.
When the ditch is completed, holes
should be dug in it from one foot to
eighteen inches deep, and from twenty
to thirty feet apart. The sides of these
holes should also be vertical, or if posi-
BILE. overhanging. The worms, unable
to climb up the vertical side of the
ditch, will crawl. along the bottom of it
and fall into the hole, where they will
soon perish. Where the soil Is. sandy,
50 that the ditch cannot be made with a
vertical side, it should be dug deeper
than in other cases, and the side made
as nearly perpendicular a. possible, so
that when the worms attempt to crawl
up, the sand will. crumble beneath
them and cause them to fall back
again. 2 -1ggras cNsEl! .
Happily, man is not left to fight the
battle alone. Blackbirds and robins
devour them in great numbers, and at
least six species of ichneumon flies prey
upon them with such effect that, accord
ing to Prot. Riley, two great army-worm
years have never occurred in immediate
succession, and are not likely to do so.
Mr.. Packard says in s Half Hours with
Insects - that ':these parasites either
attach an egg to the outside of the body
of the caterpillar, or insert it beneath
the skin" There is also Tachina fly,
an insect somewhat like the common
house-fiy, which is very destructive to
the army-worm. Il Mr.. Walsh, who dis
covered most of these parasites, in re-
porting as to their mode of attack,
states that ian intelligent farmer had
repeatedly. on damp cloudy mornings.
watched large bluish-green fly, about
the size Of a blow-dy, attacking the
arm and depositing its eggs on
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