Pesky question about a secondary pest
Suppose you had a poor stand of corn in one field in 2010, mostly in low spots. Your chemical supplier said it was caused by wireworms. Can you plant soybeans there safely now, even if the seed isn’t treated?
“Wireworms are typically a grass crop pest,” says Greg Kneubuhler, a certified crop adviser, G &K Concepts, Harlan. “You should not have any effect on the soybean crop. While soybeans and small grains are attacked by wireworms, because of seeding rates and ability to compensate for stand loss, serious losses are less common than with corn.”
Jesse Grogan, CCA, LG Seeds, Lafayette, adds a caveat. “Wireworms do attack soybean in cool, wet conditions,” he says. “Soybeans can compensate for some stand loss if damage occurs.”
If you’re worried about wireworms, seed insecticides are an option. Cruiser or Gaucho could be applied in a production plant. Or Kernel Guard Supreme, a planter box treatment, will provide some control, Grogan notes. There are no rescue treatments.
You might still have time to put out bait stations to see if wireworms are there, notes Darrell Shemwell, CCA, Posey County Co-op, Poseyville. Bait stations of wheat or other grain, covered by black plastic, attract wireworms as the seed germinates. They need to be in the ground at least two weeks before checking for the long, wiry, copper-colored insect, Grogan notes.
Wireworms will move below the soil surface once soils warm up. However, whether you worry about wireworms for beans or not, Kneubuhler says you should treat each year that field goes to corn. The wireworm life cycle runs three to seven years.
This article published in the April, 2011 edition of INDIANA PRAIRIE FARMER.