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Hundreds of plant bug species exist in Pa.
UNIVERSITY PARK -
Over 400 species of plant
bugs occur in Pennsylvania,
according to entomologists
at Penn State. These plant
bugs are the only group of in
sects that both scientist and
layman can properly call
“bugs,” says Alfred G.
Wheeler, adjunct en
tomologist with the College
of Agriculture at Penn State.
Plant bugs suck sap by
means of a beak or pro
boscis, Dr. Wheeler explain
ed. They’re relatively tiny
insects, 1/8 to 5/8 inches
long. Some species damage
crops, but not all are plant
feeders. In fact, a surpris
ingly large number feed on
other insects. The 400 are
technically known as the in
sect family Miridae.
Wheeler has studied the
biology of the more common
species of plant bugs in his
dual role as entomologist
with the Bureau of Plant In
dustry, Pennslvania Depart
ment of Agriculture. He and
Thomas J. Henry, also with
the Harrisburg bureau,
described some of their fin
dings, in the Summer issue
of “Science in Agriculture,”
the research quarterly of the
College of Agriculture.
When Dutch elm disease
began eliminating many
American elms, a search
began for other kinds of
shade trees. In the 1950’s and
1960’5, a number of thornless
and seedless varieties or
cultivars of honeylocust
were developed.
For several years, or
namental honeylocusts were
considered nearly pest free.
However, one yellow or
golden-leaved cultivar, Sun
burst, proved attractive to
the honeylocust plant bug
when the tree was grown
along city streets and in
home plantings. Plant bugs
feeding on new growth
discolor and distort the
leaflets. Large numbers of
bugs can cause premature
defoliation of entire trees.
“This is an example of an
insect that rarely damages
its host plant in its normal
habitat but has become a
pest under urban condi
tions,” Dr. Wheeler said. “It
is well known that ash plant
bugs prefer native trees
growing in open areas. They
have now become common
pests of ornamental ash in
street plantings.”
The sycamore plant bug,
Mr. Henry indicated, is
another example of an insect
that only recently has
become a pest. This insect
normally does not injure
native sycamore (American
plane tree), but often
becomes a problem when
this plant and the related
London plane tree are grown
in nurseries or along city
streets.
Sycamore plant bugs suck
juices from tender, expan
ding foliage and apparently
inject a poisonous substance
into the leaves. Plant tissue
that has been “fed on” turns
brown and drops out, leaving
many small holes in the
leaves. At one time, the
“shot-hole” appearance of
the foliage was blamed
mistakenly on frost, chewing
insects, or a disease.
Most plant bugs insert
their eggs deep into plant
stems, making detection
nearly impossible, it was
Eointed out. In this way,
ugs move long distances
with plants. A number of
European species have
entered the U.S. with
nursery stock and have
become established. While
most “imports” have re
mained harmless or
economically unimportant, a
serious pest could enter, Dr.
Wheeler cautioned.
Not so long ago, a pest of
ornamental ash in the
western states was brought
into a Pennsylvania plant
nursery with dormant, bare
rooted young trees or
“ships” grown in Oregon.
Only prompt detection
prevented this potential pest
from becoming established
in the Commonwealth, it was
noted.
“Our studies have shown
that several species may be
important biolgical or
natural predators of or
namental pests. We have
studies one plant bug that is
common on white oak where
it destroys populations of
aphids, lace bugs, and spider
mites. Two other species,
referred to as jumping tree
bugs, feed on obscure
scale.”
He added that Christmas
tree growers are aided by
several kinds of plant bugs
that feed on aphids on Scotch
pine and on gall aphids on
spruces and Douglas fir.
Spider mites on spruce trees
are eaten by another plant
bug. This mite predator,
Wheeler reported, was ac
cidentally brought m from
Europe - a rare example of
a beneficial insect entering
the country unbeknown to
scienctists.
The article in “Science in
Lancaster Farming, Saturday, September 29,187 S
Agriculture” is typical of, determine the “friend -or
each issue’s reports describ- foe” status of plant bugs in
ing research, extension, and the Commonwealth, Wheeler
resident education within and Henry claimed in their
Penn State’s College of report. With species already
Agriculture. To get on the known to be injurious, con
free mailing list for this trol has been made easier,
quarterly magazine, write to they affirm, by correlating
229 Agricultural Administra- egg hatch of the bug with
tion Building, University stage of growth of the host
Park, PA 16802. “ " '
Further work is needed to
Virginville Grange
has election
VIRGINVILLE - At the
meeting on September 20,
the following were elected as
the officers for the new year:
Master-Ernest Miller;
Overseer-Keith Treichler;
Steward-Steven Mohn;
Assistant Steward Sandra
Hill; Gatekeeper-Eenneth
Spease; Chaplin-Sue
Treichler; Pomona-Anna
Balthaser; Ceres-Brenda
Miller; Flora-Joan Dietrich;
Secretary-Joyce Miller;
Treasurer-Arlan Seidel;
Finance Committee-Leroy
Shollenberger; Executive
Committee-P. William
Stitzel; Lecturer-Carline
Blatt; Pianist, James
Schlegel.
At the next meeting on
Oct. 3, the officers will be
installed starting at 7:30
p.m. On October 1 the
women will meet and do
needlepoint. An appreciation
banquet will be held at the
Kutztown Grange hall on
October 13.
The youth will meet on
October 2 at 8 p.m. They will
sponsor a dance Oct. 20 with
plant. In this way, insec
ticide sprays can be timed,
with best accuracy.
music by the Driftwoods. In
the softball playoffs,
Virginville is the champion
team of the district.
The social committee
thanked all who made salads
for the outing and asked all
to bring desserts to the next
meeting.
They will have a sale on
October 9 and are asking for
help and pastries.
The program for the
evening included a skit, “It
is all in what goes into it”, by
Steven Mohn, Ella Wessner,
Richard Kieffer, Kim
Stump, Richard Schaffer,
Brenda Miller, and Scott
Miller, and the an
nouncement of the Granger
of the Year as Kenneth
Spease.
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