Page 12—Corn Talk, Lancaster Farming, Saturday, October 9,1993
Producers Should Analyze Corn Test Plots, Take Notes
(Continued from Page 1)
than they would be if the indus
try standard where that produc
ers were more scientific in
selecting a variety.
For several years, Craig has
been working with Penn State
University corn variety
researchers and county landow
ners who allow the university to
set up com variety trials. These
“university trials” occur all
over the state and the results
compiled and published
annually.
However, Craig said he
thinks the value of the informa
tion may be lost on a lot of pro-
These offending larva can do great damage to a com
field. They are present in many, but some plants have been
bred for resistance. To determine apparent resistance at a
variety test plot, visually inspect each variety. An underde
veloped husk can allow infestation and bird dam.
> ' * v *
This graph is the la/out of a university corn variety field trial
located in upper Dauphin County on a cooperating farm.
ducers, unless they understand
the differences between the dif
ferent types of trials and how
they are conducted.
According to Craig, the
greatest value is not necessarily
in the compiled and compared
data; the greatest value comes
to those who actually visit test
sites, use a systematic and
recorded analysis, and ask
questions of the actual person
who planted the crop.
Yield data alone is not suffi
cient for a producer to make a
decision on selecting a new var
iety for his farm, Craig said.
A producer must consider his
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needs for the com, such as
whether he plans to use it for
silage or grain, high moisture,
left in the field to sell as silage,
etc., instead of deciding the best
use of a crop after it is planted.
Also, the producer should
consider all the other character
istics of a plant which are
important to him in his
operation.
Craig said there is much
information available on each
variety’s resistance to disease
and pests, apparent suitability
to local climate, germination
rate and yield. However, before
being sold on a new variety,
other characteristics and grow
ing specifics should be looked
at.
Such specifics as soil type
best suited for the variety, seed
ing rate, ease of harvest,
strength of stalk, number of
barren plants, hardiness, the
range of variability in a com
variety’s mature plants, are just
a few which may be considered.
Therefore, according to
Craig, while much data can and
should be gained about plant
variety potential through com
mercial company reports, and
private test plots planted by
seed company representatives,
the producer has to know his
fields and specific climate in
order to use that information.
Craig said one of the first
things that producers should
realize is the difference built
into com variety trials.
There are basically three
types of com variety trials typi
cally available for examination
by Pennsylvania-area produc
ers “university” trials, com
mercial seed company trials,
and owner-producer trials.
University trials are the most
objective and should be consid
ered the best for getting the
actual data for a specific grow
ing season.
However, that doesn’t mean
the commercial test plots are
not objective or useful.
Craig said that producers
should use seed company data
for information on a variety’s
potential.
Seed companies are con
stantly trying varieties in com
parison to lines already known.
While the conditions under
which those trials are con
ducted may not apply to a spe
cific farm, the information the
seed companies provide should
be considered to be of high
quality, Craig said.
If that information isn’t
available, Craig said producers
should request it. and use it.
Data derived from university
trials (done throughout the state
every year with the cooperation
of seed companies) are consid
ered more objective because all
varieties are planted on the
same day, at the same time,
with the same amount of nutri
ents in the same field, and the
test plot is designed to elimi
nate the influence of soil varia
bility which can be great over a
very small distance even in a
small field.
Also, all harvesting is done
on the same day so maturity and
Paul Craig, Dauphin County Extension agent, pushes
back on the top end of a com plant to test the stalk strength,
an important consideration in variety selection.
The ear on the right comes from a corn plant at the end of
a test row, where competition from other plants for light and
water and nutrients is not as great as further back into the
field. The ear on the left is the same variety, only from a plant
about 15 feet into a row. What the large ear shows the
observer is the genetic potential of the variety, given good
to optimum conditions. The ear on the left apparently
shows what happens when the same genetics are stressed
from certain competition. In a variety test plot, comparing
each variety’s differences between end-row ears and in-row
ears in the same field, under the same conditions, can indi
cate the ability of one variety over another to withstand
competition, under specific, but identical conditions.
yield differences under specific
conditions are actual.
The producer-owner trials
are done by the producer for
himself on his own farm. These
trials are not necessarily open
to public scrutiny, but are used
by a producer in keeping track
of each variety’s success under
real farm conditions.
While this may seem as
excessive data collection, Craig
said it can mean the difference
between staying in farming or
failing.
First of all, according to
Craig, it must be considered
that even on one small farm a
great range of crop-growing
conditions can occur. The range
of conditions in a county can be
extreme.
In fact, the hatchet-shaped
Dauphin County in which
Craig works contains a wide
range of growing conditions
the more temperate valley lands
of southwestern Dauphin
County are much different from
the Lykens Valley fields; and in
the Lykens Valley there is a sig-
(Tum to Pago 13)