But, according to a
recent survey in northwestern Illinois by integrated pest management
and crops educators from University of Illinois Extension, nematodes
can cause early season problems irrespective of soil type.
"The educators teamed
with commercial fertilizer dealers and other Extension personnel to
be part of the team collecting soil samples," said Dave Feltes,
integrated pest management educator at the East Moline Center.
"Forty-eight composite samples were collected from Whiteside, Henry,
Brown, Bureau, Henderson, Menard and Hancock counties and submitted
for analysis. Both sandy and fine-textured soils were sampled."
For all soil samples,
the population of each nematode species was rated as insignificant,
minimal, moderate, severe or very severe in terms of the amount of
damage they could cause to a corn crop.
"Ratings of severe
and very severe can cause corn yield losses of 50 percent or more,
depending on soil and environmental conditions," Feltes said. "The
results indicated that 79 percent of the samples were positive for
soybean cyst nematode."
He noted that 90
percent of the samples were positive for spiral nematodes, with
three of the 43 positive samples rated severe and four of the
samples rated moderate in the amount of damage they could cause to a
"In addition, 54
percent of the samples were positive for lesion nematodes, with 5
percent the samples rated very severe or severe in the amount of
damage they could cause to a corn crop," Feltes said. "About 52
percent of the samples were positive for stunt nematodes, with all
levels rated as causing minimal damage to a corn crop."