Evening star. [volume] (Washington, D.C.) 1854-1972, 1907-09-12
PEST|FEROUS TUSSOCK
Army of CaterpiIIars Devouring
Washington Foliage.
GREAT DAMAGE WROUGHT
Trees in Sections Almost Bereft of
Their Leaves.
SUGGESTIONS BY SCIENTISTS
Worms Drop From the Trees Upon
Pedestrians-They Invade Houses.
Become General Nuisance.
SUGGESTIONS BY SCIENTISTS

Become General Nuisance.
Foliage on Washington's trees is being
devoured wholesale by an army of tussock
catorpillars, the larvae of the tussock moth,
and apparently nothing can be done to
check the ravages of those now doing the
DANA ge,- though precautions can be taken
against repetition of the pest next year.
Aiding and abett.ng the tussock cater
pillars are the cohorts of the fall web
worms" which a.e by no means nu-
nervous but which nevertheless, are doing
an immense amount of damage.
For many years the tuSsOck caterpillar
has been the most serious of the shade
tree pests in Philadelphia, New York,
Brooklyn and Boston, but it was not until
1895 that it appeared in Washington in suf
ficient numbers to be regarded as 4 menace
to the foliage. In that year also the fall
web worm was more abundant in this city
than il had been since 1885. In 1901 the
pests of both kinds again appeared in great
numbers, and now there is another inva-
sion, giving a period of six years between
each great attack
Hitherto the chief check upon the insects
has been the parasites that come i'll great
numbers in the same years that the cater
pillars dDOuNQ ana destroy most OF lDe
multitude of eggs laid by the pests. De
struction by man has helped, but has ac-
counted for but a small percentage of the
eggs put out of business.
Some Trees Immune.
Trees of which the foliage has been in
jured or even totally destroyed by these
marauders may be seen on almost any
street of Washington, the caterpillars at
lacking by preference poplars, soft ma
pies, Gins, alders, birches and willows. But
other trees by no means escape their dep
relations. though the gingko and tulip are
almost immune. Besides destroying the
foliage the caterpillars extensively In
trusive, invading the homes of the resi-
dents, and otherwise becoming a nuisance.
AS usually seen, the tussock caterpillar
has two big, hairy frotuberanceS like horns
sticking out of where his forehead would
be if he had one. and another one-really
two close together-projecting like the rud-
der of an airship. He Is excessively hairy
and ugly, and his hairs are stuck in loosely
and are apt to fall out on any person upon
whom he drops, causing irritation of the
skin and sometimes severe infiammat ton
and swelling. These hairs are finally tam
gled up in the silk as the caterpillar weaves
his cocoon, and become part of the egg re-
Ceptacle, leaving the caterpillar smooth
worm,'' not ''woolly one and looking
far unlike his original hirsute self.
Three Generations in One Year.
Three generations are born in Washing
ton every year, and each caterpillar casts
it's skin FIVE times, exhibiting a different
character after each mott. The newly
Matched young feed on the under surface
of the leaf, eating off the parenchyma and
producing skeletonzed appearance. After
the first mott the skeletonizng continues,
but a few hoes are eaten completely
through the leaf; after the second mott
hnla nafa hnfyr
the main ribs and after the third mott the
leaf is devoured. except for the mdrib and
it's principal branches. After the fourth
mott the caterpillarS begin to eat from the
edge of the leaf and devour everything
except the principal veins. Similar work
is done in the last stage upon the full
grown and tough leaves.
The young caterpillars, when shaken from
a tree, or blown by the wind. or perhaps
sometimes in n spirit of adventure hang
at the end of silken string in wait for
the unwary pedestrian or vehicle Dropping
then upon some moving object, they are
carried from place to place, and thus are
spread. This, in fact. is the only way in
which they be disseminated, except by
a general migration from q tree which
their voracious apperites have deforiated
and left stripped of every edible vestige, for
the female of the moth is wingless, and
must, perforce, lay her eggs at the spot
where she herself has sprang into being.
Brown, With White Markings.
The male is a brown moth, with white
markings, and after he starts to fly he goes
in search Of his mate whom he finds living
on the cocoon from which she issued The
female moth is an extremely hideous bug
but she has the merit of not being a CAD
about, which is not true of any female
of her genus except the gypsy moth. Tho
family name is 'orgyia leucostigma" The
latter word meaning "white-marked" and
the former probably something extremely
unpleasant and insulting
The caterpillars that are Matched about
August begin to spin their cocoOns about
September g. and by September IA the first
male moths VIII issue, the female issuing
about September 10 The caterpillar trans
forms into pupa within few hours after
II has spun its cocoon. AS soon as the fe-
male has laid her eggs she dies, and then
falls to the ground, though sometimes her
shriveled body may be seen clinging to
the upper part OF the cocoon, to which is
fastened the ghstening mass of eggs that
cost her life.
Sometimes the cocoonS are spun on fences
or other objects near the trees upon which
the caterpillars have lived. but usually they
are on the tree itself. upon the trunk o. the
crotches of the main limbs.
Tussock Moth Parasite.
The parasite of the tussock moth is the
'Pimpla inquisitor,'' which invades the CO.
Coons and destroys the eggs. 1t is these
parasites that have checked the pest on the
two former occasions when 1t became as
marked in Washington il is now the
number OF parasites increasing as rapidly,
apparently, the number of caterpillars
From experiments carried on this year at
the bureau of entomology in the Depart
ment of Agriculture. il is found that the
eggs are parasitZad, and that a similar
check may be looked for this time. guaran-
teeing that next year no more than the
usual number of catcrpl'ars will infest the
trees.
Precautions may, however, he taken. and
probably will be. The eggs may be scraped
off i'll winter and burned or the egg masses
may be touched with a sponge dipped in
creosote oil and turpentine, backened with
tar. so that egg masses which have been
touched may be recognized at glance
Trees may be sprayed. destroying the cater
pillars OF the first generation so that the
second and more destructive genera ton
may be prevented. Unattached trees may
be banded to prevent the ascent of cater
pillars seeking fresh forage.
The fall web-worm. "Hy phantria Guinea ="
has but two generations a year. against the
tussock moths three. The eggs are laid in
clusters of four or five hundred on either
the upper or under surface of leaves and
the caterpil,ars feed gregariously ike so