Page 4—Com Talk, Lancaster Farming, Saturday, October 14, 1995
Penn State
ANDY ANDREWS
Lancaster Farming Staff
ROCKSPRING (Centre Co.)
Research on com row
widths could prove fruitful
literally by increasing the
amount of com harvested per
acre.
Now, only if the researchers
could woric out planting and
harvesting challenges ....
Potential benefits of using
15-inch rows instead of the
standard 30-inch rows include
an earlier canopy, better weed
control, improved soil conser
vation, more nutrient uptake,
and possibly higher yields,
according to Greg Roth, associ
ate professor of agronomy at
Penn State.
At this year’s Weed Field
Day held at the Landisville
Research Station, Roth spoke
about the ongoing research at
Penn State to study the poten
tial of narrower com row
widths.
Penn State has put out “a
number of simple trials at a
number of locations” compris
ing four years of research, said
Roth. There arc 10-15 sites in
the database and rive locations.
“Results have been generally
pretty promising,” Roth told
Potential benefits of using .
the standard 30-Inch rows Include an earlier canopy,
better weed control, Improved soil conservation, more
nutrient uptake, and possibly higher yields.
- yea ogress Days, Steven _ Ith, Penn State research assis
tant, provided information on the narrow width corn rows. A demonstration
plot showed 15-Inch rows planted at a density of 34,000 plants per acre. The
demonstration seedbed was planted Miy 10.
Examines Promises, Potential For Narrow-Row Com
those who attended the Weed
Field Day. Penn State has
investigated two different sys
tems. using 30-inch rows at a
population 0f27,000 plants per
acre and IS-inch rows at a
population of 34,000 plants per
acre.
At this year’s Ag Progress
Days, displays showed some of
the promising results of initial
research. In 1993, yield
response climbed to 7 percent.
In 1994, researchers at
Rockspring saw an 18 percent
yield response.
At this year’s Ag Progress
Days, Steven Smith, Penn State
research assistant, provided
information on the narrow
width com rows. A demonstra
tion plot showed IS-inch rows
planted at a density of 34,000
plants per acre. The demonstra
tion seedbed was planted May
10.
Smith said the biggest chal
lenge facing growers is adjust
ing the right equipment and
that, during planting and
harvesting, the equipment
moves slower than convention
al 30-inch plantings.
Roth said the yield increases
at Rockspring were “probably
above normal and mostly due to
At this year’s Weed Field Day held at the Landlsvllle Research Station, Greg
Roth, Penn State associate professor of agronomy, far right, spoke about the
ongoing research at Penn State that examined the potential of narrower corn
row widths. From left, BUI Curran, weed specialist; John Yocum, research sta
tion manager; and Roth.
the increase in population.”
Researchers are looking at
silage use of the narrower rows,
which is being adopted readily
in New Yoric, according to
Roth. One location in Quarry
ville, Lancaster County,
showed a 3.S percent overall
increase, giving a very good.
30-ton silage yield.
A site in Lebanon showed a 1
percent increase, for 22 tons of
silage.
Rockspring showed an 11
percent increase, for a 23-ton
com silage yield increase.
“Our early results are sort of
saying there might be some
room for this,” said Roth.
Roth pointed out that the
greatest potential may be for
parts of northern Pennsylvania,
where the com remains short
well into the season and cano
pies over later, and where it is
more difficult to obtain good
stands. These areas “might ben
efit more from the narrow rows
than down here in the south
east,” said Roth.
The researcher wants to see
if his theory holds out—that as
“we move north, we’re probab
ly going to see these narrow
rows pay off more nicely.”
The problems growers face
include retooling equipment to
plant and harvest narrow-row
com and working around the
problems of applying pesticide
and fertilizer products post
emergence.
Research at the USDA Belts
ville, Md. laboratory has shown
benefits with reducing herbi
cide rates with narrow row com
and improved weed control.
Watch For
Com Stalk
COLUMBUS, Ohio—An
Ohio State University agro
nomist cautions farmers to
watch for serious com. stalk
lodging problems at harvest
because of the effects of the
past growing season’s weather
and disease stresses.
Peter Thomison said drought
and hot weather during the
com plant’s grain-fill stage,
combined with widespread
late-season foliar disease dam
age, have increased the likeli
hood of serious stalk rot prob
lems in many Ohio com fields.
“Given these prospects,
growers in some areas could
incur significant grain losses if
they delay field harvest to
allow for natural drydown,”
Thomison said.
Healthy stalks require
enough carbohydrates pro
duced by photosynthesis to
keep both pith cells and root
cells alive during grain fill.
However, photosynthetic
activity was sharply reduced
by either drough or heat from
July through early September,
and carbohydrate levels were
insufficient for developing
ears, in some cases. Stressed
plants compensated by trans
ferring carbohydrates to the
ear, resulting in premature
death of pith cells and root
tissues. This predisposed
plants to root infection and
stalk rot fungi.
In addition to drought stress
during grain fill, the past grow
ing season was unfortunately
favorable to the development
of foliar diseases that
weakened the stalks. The most
The potential for using
narrow-row com is “the kind of
thing I want to take a a good,
long look at,” said Roth. He
told growers at the Weed Field
Day, “When we make our deci
sion about it, I'll keep you
informed and hopefully you'll
get behind us if it looks promis
ing for some areas.”
Serious
Lodging
important by far is gray leaf
spot, while Stewart’s bacterial
blight was evident to a lesser
degree. Second-generation
European com borers also
injured stalks in some areas.
Other stresses that can
increase the likelihood of stalk
rot are tissue loss from hail
damage, insect or chemical
injury to the root system, high
levels of nitrogen in relation to
potassium in the soil, com
pacted or saturated soils
restricting normal toot growth,
and high plant populations.
In most hybrids, stalk rot
symptoms do not show up until
shortly before the black layer
stage, coinciding with physio
logical maturity. The main fun
gal pathogens causing stalk rot
in Ohio are Gibberella, Collec
totrichum (anthracnose) and
sometimes Fusariura. It is often
difficult to distinguish between
stalk rots because two or more
fungi may be involved.
Assessing a potential lodg- (
ing problem is fairly simple j
because the deterioration of
inner stalk tissues is a symptom ,
common to all stalk rot. These
tissues will easily compress
when squeezed between the
thumb and finger. Use this
“squeeze test” to determine the
extent of stalk rot throughout a
field. Give the most damaged
fields priority at harvest.
“This is not the year to allow
com to dry in the field to mois
ture levels of the low 20s or
high teens before harvest to
save on drying costs!” Thomi- ;
son said. '