Al6—Lancaster Farming, Saturday, May 31,1980
How fanners can beat corn borer infestation •
BLOOMINGTON, 111. -
Keeping ahead of corn borer
infestation is a problem
faced by termers wherever
corn Is grown, says En
tomologist Gary Beland.
Although in general the
pest did not affect the 1979
com crop to the extent of a
year ago, in specific
locations infestations were
worse than in 1978.
Two types of corn borer
can be found in the United
States. The European com
borer strikes fields
throughout the midwestern
Com Belt, as well as from
southern Kansas, east to the
northern portion of South
Carolina and up the Atlantic
coast into the Northeastern
states.
The Southwestern corn
borer is a problem in the
southern corn growing
states.
Beland says full-grown
corn borer larvea over
winter in field residue. These
larvea turn into pupae, and
months emerge by the last
week in May or the first
week in June. Soon after, the
moths begin to lay eggs that
will produce the first
generation, or brood, of corn
borers.
The corn is at the young
whorl stage when the larvae
hatch and the pests feed on
developing leaf tissue in the
whorl.
If not controlled, the
larvae will eventually bore
into the stalk and then go
into a resting stage as pupae
for the second generation.
Com borer control begins
with the scouting process,
says the Punk Seeds
researcher. Farmers should
start looking for the eggs
when the com is between 25
and 40 inches in extended
leaf length, or when it is
between calf and knee
height.
Egg masses, each con
taining from 15 to 30 eggs
(fewer for the Southwestern
com borer), are deposited on
the underside of the leaf,
near the midnb. The eggs
overlap, resembling fish
scales.
Five or six days after they
are laid, black spots appear
on the eggs, which are ac
tually the head capsules of
the developing borer larvae.
Hatching occurs within 24
hours of this ‘blackhead’
stage and within days,
feeding damage can be
observed.
“As the young larvae feed,
they cause a characteristic
‘shot-hole damage’ pattern.
These holes become ap
parent as the leaves grow
out of the whorl. To check for
damage, look at 20 con
secutive plants m five dif
ferent areas for each 40
acres,” says Beland.
Patz
★ Bam Cleaners, Manure Pumps,
Manure Stackers, Silo Unioaders,
Bunk Feeders, Feed Conveyors
MARVIN J. HORST
DAIRY EQUIPMENT
1950 S. sth Avenue, Lebanon, Pa. 17042
Phone: 717 272-0871
“Earliest planted com is
the most susceptible to first
brood and should be watched
the closest.
“Count and record the
numer of plants showing
foliar feeding damage,"
Beland continues, “and
divide the number by 100 to
figure the percentage of
injured plants.
“Determine if borer are
still present and actively
feeding in the field by
examining the whorl area of
several plants showing
feeding damage."
“If foliar damage is 50
percent or above, and live
larvae are present, chemical
control should be used,” he
says.
Aerial application of
diazinon, Oyfonate,
Furadan, Sevin or Thimet at
rates recommended by local
extension services can be
used for control of first
brood com borer.
“A single chemical ap
plication is usually effective
as long as it goes on within 14
days after the larvae start
feeding on the leaves,” says
Beland.
“After that time the larvae
will have bored into the
stalks.”
Beland points out that first
generation com borer does
not do as much damage as
second generation, although
it can cause stunted plants
and reduced yields by stalk
tunneling which weakens the
plant, destroys tissue used to
transport water and food
within the plant and in
creases susceptibility to
stalk rot and other disease
organisms.
Control of the first brood is
necessary, however, to
prevent a large second
generation.
Moth emergence for the
second com borer cycle
begins from mid to late July,
although it may be earlier in
southern states and later in
northern states.
The moths lay their eggs
during August on the un
dersides of corn leaves in the
ear node area (usually the
middle third of the plant).
After hatching, the larvae
move from the leaves to the
leaf axils and sheath areas
where they feed on the pollen
and plant tissue in the area.
Hatching of the larvae
usually comcides with pollen
shed, Beland says.
Later, they bore into the
stalks and ear shanks, which
may result in stalk breakage
and/or ear damage. In
addition, there is a greater
possibility for stalk rot as
damage from the com borer
increases the stalk’s
susceptibility to invading
fungi and bacteria.
“It is important to scout
for the second brood while it
Know how the critter lives
is in the egg mass stage,"
says Beland. “Once the
larvae hatch and start
feeding, they’re hard to
find.”
Beland recommends
scouting for the second
brood about the time the
local extension service
announces the starting of a
second brood moth flight.
The scouting method is the
same as for the first
generation.
Spraying is necessary if
Maryland 4-H Foundation raises funds
COLLEGE PARK - Ten
years ago, 37 Maryland
banks contributed a total of
$2,185 to help support 4-H
youth programs m the Old
Line State. This year, the
Maryland Club 4-H Foun
dation hopes to raise $150,000
in its “Worth Your In
vestment” fund campaign
aimed at a full cross-section
of the state’s business
community
inflation during the past
decade represents only a
portion of this greatly in
crea ed need, reports
Maun n e J. Spencer,
assis art director of the
MaiyU-nl Cooperative
Extens cn Service and
statewide 4-H department
chairman at the University
of Maryland in College Park.
More importantly, the
example represents changes
in 4-H programming for
Maryland youth. It is an
attempt to respond to the
challenges of the 1980’s and
beyond, Spencer em
phasized.
An American invention,
the 4-H program is
operational in all 50 states. It
originated near the begin
ning of this century as a
result of a vital need to
improve life in rural areas.
Designed for both boys and
girls, the first 4-H projects
included home canning of
tomatoes as well as raising
com and hogs. But the 4-H
program now offers more
than 100 youth education
projects, including such up
to-date topics as aerospace
science, consumer education
and energy conservation-to
name just a few
A network of adults and
older teen-agers donate
untold hours as volunteer
leaders of local 4-H clubs.
Without this, the 4-H
one or more egg masses are
found per plant. It should
begin at the time the egg
masses are in the blackhead
stage or just beginning to
hatch.
Chemicals are the same as
for the first generation.
With the second brood, it
may be necessary to go back
and scout the field after a
week for eggs, since not all
the moths emerge at the
same time.
Beland notes many
program could never have
been as successful as it has
been for the past three
quarters of a century.
But increased
sophistication of modern
youth clientele requires
ever-increasing quantities of
educational publications and
audio-visual training aids.
Skyrocketing transportation
costs and higher-pnced food
and lodging elevate budgets
for regional and statewide
planning meetings,
educational conferences and
summer camps.
Then, there are new kinds
of youth projects to help
extend the usefulness of 4-H
affluent locales like
National Grange Sewing Contest winners
HARRISBURG - Penn
sylvania winners of the 1980
National Grange Sewing
Contest were announced by
Charles E. Wismer, Jr.,
Master of the Pennsylvania
State Grange in Harrisburg.
This year’s contest had
over 1300 entries hailing
from every Grange County
in the State of Pennsylvania.
The winner of the coveted
Best-of-Show Award was
Pamela Mignerey, of
Honesdale, Wayne County.
Mignerey’s winning entry,
also the Youth Class winner,
was a maroon, hooded
jacket, lined with fleece.
The winner of the adult
class was Renee G. Beitler,
Schnecksville, Lehigh
County. Beitler’s entry was a
three piece suit, consisting of
a beige slim skirt, a lined,
printed blouse, and a lined
jacket with a white piping.
Winner of the children’s
class was Mrs. James R.
Haunstem, of Marysville, in
Perry County. Haunstem
growers are too busy to
check their fields regularly
and that there is a growing
trend to hire professional
scouts to take care of the job.
The battle against com
borers has been made even
more difficult as con
servation tillage increases.
Shredding stalks in the fall
along with clean plowing is
effective in reducing com
borer population, if done by
most farmers in an area, but
this goes against the trend to
Royal Oak (Talbot county),
on Maryland’s Eastern
Shore, to underprivileged
areas like Roland Park in
inner-city Baltimore.
Some of these new projects
are still in the develop
mental stage. They include
things like dog training and
horseback riding for the
handicapped-both classified
as animal science projects
and “Adventures in Vision,”
an eye care activity just
getting started as a health
science pilot project m
Montgomery county.
These three new activities
alone call for $15,500 in the
1980 fund drive budget.
Proposed training sessions
sewed a toddler’s outfit done
in white with a yellow
Rosebud print. It had a
smocked-yoke front, with a
Peter Pan collar. The outfit
was made for her 14-month
old daughter, Jennifer.
reduced tillage, the Funk
entomologist states.
Hybrids are available that
are moderately resistant to
the leaf feeding of the first
brood larvae.
The hybrids, while not
immune to the first brood of
com borers, do show less
leaf feeding than susceptible
hybrids. Hybrids with high
levels of resistance to the
second generation are not
yet commercially available.
for adults and youth
including statewide summer
camps-come to more than
$50,000 for the year.
The Maryland 4-H Club
Foundation busings
campaign began in JamiSPf
at the corporate
headquarters of McCormick
and Company in Hunt
Valley, north of Baltimore. A
wrap-up luncheon is
scheduled during a June 27-
29 statewide older youth
activity.
Volunteer chairman for
the fund drive is Donald W.
Dick, Jr., of Fallston
(Harford county), vice
president and treasurer of
McCormick and Co.
for PA announced
Sandra Deitrich, Ham
burg, Berks County, swept
the honors for Class D, boys
and girls. The twelve-year
old seamstress won the class
with a blue and white Swfcs,
dotted sundress.