The San Juan islander. [volume] (Friday Harbor, Wash.) 1898-1914, 1912-08-30

(By FRED E. BROOKS. West Virginia
Experiment Station.)
The grapecane girdler is an insect
not often mentioned in chronological
literature, probably for the reason that
in the past it seems to have confined
its attacks chiefly to the plant known
as Virginia creeper or five-leafed ivy,
ampelopsis quinquefolia, and has
seemed, therefore, Of but little eco
ncmic Importance. In this state it APP
pears now to have developed prefer
ence for the grape. In several local.
ties have seen grapevines 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
it's work on ampelopsis.
The species cannot now be regarded
as pest of very serious consequence,
except in rare instances, but it has
several times attracted attention as an
enemy Of the grape in this state dur
ing recent years, and heretofore but
little has been known in regard to its
habits.
The distribution of the species
seems to be quite general throughout
the eastern and mid-western sections
Of the United States. In 1862 Mr.. G.
v. Riley, in his first report on the nox-
ious insects of Missouri, mentioned It
as forming gals on the common creep
er. At about the same time Mr.. Benz.
D. Walsh had specimens Of the insect
in his collection in Illinois, marked
"Madarus ampelopsis." It was not I'M
til the year 1875 that description
Of the beetle was published. In that
year DIR. John l.. LeConte described 1t
in his work on the Rhynchophora OF
America, and gave to 1t the name
which 1t 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
notice, but has been recorded as oc-
curing in several states from MIS-
souri, to Pennsylvania.
The wound which the beetle makes
in ovipositing causes the tip and
terminal leaves on 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.
It is Interesting to compare the
methods Of this insect with those OF
other species that girdle twigs or
small branches in order to kill or part
| " kill the wood in which their eggs
are laid and their larvae are to iced.
The sehickory twig-girdler, Onci-
deres cingulata, 'long-horned' bee
tie. lays It's eggs in the branches o.
hickory and other trees and then CIR
dles me branch below, by cutting
deem groove with its strong jaws 90
that the branch above dies and Is ire
ouently broken on By the wind. Ine
selm tWig-girdler." Oberea uimicQla.
1 beetle Of the same family, attacks
ain il ! sfmilar manner. The female
cnts ! deep groove around twig 90
that ii Is easily broken on ~ me
wind. Below the groove she cuts 2 slls
"a the bark and depositssan egg ano
then moves further down the tW1E ano
eirdles ii second time, now merely
cutting through the bark - - g deaa-
a. the part aboye. Another spscaes g
ia eanne sxenus, known a. the pleclEs
49, cane. efrd1er. oberea b1mAcNs