Rootworms could prove costly
to corn, soybean farmers
By Anna Herkamp
Summer
Reporter
Windy thunderstorms like those seen earlier this
week could be a cause for concern for some corn and soybean farmers.
Rootworms are a fairly typical problem for this
type of year, said John Obermeyer, integrated pest management supervisor.
The main reasons are that corn is growing rapidly, the worms have completed
most of their feedings and storms with heavy winds and rain can cause
the plants to topple or fall down, he said.
If a producer is seeing damage to his crops, there
is a good chance that they will have yield reduction because of it.
They can have up to a 30 percent reduction from normal yield, Obermeyer
said.
A problem preventable only during planting in late
April, corn rootworms are best hindered at the beginning of the growing
season.
Most of the time, rootworm problems become apparent
only after thunderstorms. This is when lodging, or near toppling of
corn plants occurs. Under normal circumstances, without the worms, corn
plants will not be blown over in a storm. However, with the presence
of rootworms, the plants are weakened because the worms damage the roots
of corn and soybean plants.
Farmers are advised to begin checking for the worms
in early June.
New research in the School of Agriculture has yielded
a new way to combat the insects.
A few years ago, the main solution farmers used
to combat the rootworms was to rotate crops year to year from corn to
soybeans. The theory was that planting corn on top of corn year after
year led to problems with the corn plants, said Jeff Phillips, extension
educator at the Tippecanoe Extension Office. They also infested the
soybean plants, so an insecticide was developed to kill the worms as
they grow in the plant roots.
Phillips said using a new type of trap for the
adult beetle helps determine whether or not insecticide needs to be
used for the soybean crop.
The new method involves putting yellow cards with
a sticky material into the fields to trap and collect the beetles, he
said.
Once a week, farmers go into their fields and count
the number of beetles they've trapped. They go through this process
for about six weeks and at the end of that time they can get an average
of how many insects inhabit the crops. This information can tell the
farmers whether or not they need to use insecticide.
To help combat any problems farmers are having
with rootworms at the present time, Obermeyer said he is encouraging
farmers to take a look at the extent of the damage in their fields.
If farmers are utilizing the insecticide and still see problems, there
may have been a problem with the performance of the insecticide, he
said.
Usually, the producers will be compensated for
poor insecticide performance, he said.
Some of the lodged plants may be harvested anyway,
depending on the extent of the damage, he said.
For now, there is no way to totally get rid of
the rootworms. "You can't eliminate an insect. What we try to do is
reduce it so it does as little damage as possible to crops," said Obermeyer.
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