WAHOO – Crop chomping caterpillars are being spotted by many farmers this year.
This spring and early summer, there has been a higher than normal number of field damaging caterpillars.
University of Nebraska Extension Educator Keith Glewen said while the number of these caterpillars is much higher than normal this year, these insects are not a new problem.
This year’s pests have been identified as three species of caterpillars that are common to the area – the Thistle, the Painted Lady and the Red Admiral. Of the three, the Thistle is the most common.
“These will forage on 200 different types of plants,” Glewen said.
Both soybeans and corn plants will make a meal for the caterpillars.
Despite their high numbers, in most situations, it’s unlikely that field yields will be affected to any great extent. Glewen said once the caterpillars begin to cocoon for seven to 14 days and hatch, they will no longer feed on field plants.
“We’re seeing them nearing pupating, so they’ll no longer be a problem,” he said.
However, he warned that while this generation will be unlikely to cause much in the way of damage, the next generation may cause issues.
Within the next month to a month and a half, provided favorable weather, the second generation of caterpillars may hatch in high numbers. That’s when concerns over damage may become a more legitimate issue.
Until then, farmers can only wait.
As for a means of prevention, Glewen said insecticides can be used, but it’s often best to wait to properly scout the field to determine the levels of infestation. Then, the decision to spray can be made.
Spraying can be very expensive, so using insecticides unnecessarily can be a large financial drain.
“We don’t want to put insecticides in the air unless they’re needed. At this point, we just don’t know,” Glewen said.