The Yale expositor., 1912-08-08

(By FIRED f. BLOCKS. West Virginia
Experiment St2tiOnO
The grapecane girdler is an insect
not often mentioned ia chronological
literature, probably for the reason that
in the past Il seems TO have confined
It's attacks chiefly 10 the plant known
as Virginia creeper or fiNe-leafed ivy,
ampelopsis ouinquefoiia, and has
seemed, therefore, OF but little eco
ncmic Importance. In this state 1T ap-
pears now to have developed q prefer
ence for the grape. In several locali-
ties have seen grapeyines presenting
a ragged appearance on account of the
dead tips resulting from the insects
attacks, but / have never been able to
find either the beetle or evidences of
its work on ampelopsis.
The species cannot now be regarded
as pest of very serious consequence,
except in rare instances, but il has
several times attracted attention as an
enemy OF the grape in this state dur
ing recent years, and herStofore but
little has been known in regard to its
habits.
Tie distribution of the species
seems to be quite general throughout
the eastern and mid-western Eections
of the United States. IN 1862 Mr.. G.
V. Riley, in his first report on the nox-
ious insects CT Missouri, mentioned it
as forming gals on the common creep
or. At about the same time Mr.. Benz.
d. Walsh had specimens of the insect
in his collection in illinois, marked
"Madarus ampelopsis." 1t was not un-
til the year 1876 that a description
of the beetle was published. In that
year Dr.. John L. LeConte described it
In his work on the Rhynchophora Of
America, and gave to 1t the name
which it still bears. lie Conte gives
its geographical distribution as south
ern and western states Since the
description was published the species
has received but infrequent and brief
r1tice, but has been recorded as oc-
curing in several states from Mis-
souri, to Pennsylvania.
The wound which the beetle makes
in oyipositing causes the tip and
terminal leaves OH the young cane to
drop over and die, and shortly after
ward to fall from the vine. The egg
Is not carried to the ground with the
prunings when they fall, but it re-
mains in the vine, and the larva which
develops therefrom feeds in the heart
OF the stump from which the leaves
and tip were removed.
1t is interesting to compare the
methods of this insect with those OF
other species that glrdle twigs OF
small branches In order to kill or part
Iy kill the wood in which their eggs
are laid and their larvae are to feed.
The "hickory twig-glrdler," Onci-
deres cingulata, a 'lcnghorned" bee
tie, lays it's eggs in the branches Of
hickory and other trees and then Cir
dies the branch below, by cutting
deep groove with its strcng jaws SO
that the branch above dies and is fire.
quently broken off by the wind. The
elm twig-girdler," Oberea ulmicola,
beetle of the same family, attacks
elm in a similar manner. The female
cuts a deep groove around twig so
that It is easily broken of by the
wind. Below the groove she cuts slit
in the bark and deposits an egg and
then moves further down the twig and
girdles II a second time, now merely
cutting through the bark so os to dead.
en- the part above. Another species Of
the same genus. known as the black
berry cane-glrdler," Oberea bimacu.