What is in this article?:
- Soggy crops presented 2013 insect control challenge
- Plant bugs often over-looked
- Plant bugs disappeared quickly
- Prone to build up late
• Combine the higher than usual populations of plant bugs, with usually high stink bug populations, lower than expected corn earworm populations, early fall armyworms and kudzu bugs and growers found more and more problems getting the right insecticide on at the right time to take care of different combinations of these pests.
MULTIPLE INSECT pests in late-season crops was a ‘mess’ said Virginia Tech Entomologist Ames Herbert.
Plant bugs disappeared quickly
For example, the North Carolina State researcher said a sweep net sample of plots at the Blacklands Farm Managers Tour site in Terra Ceia in eastern North Carolina this year showed 35 adult plant bugs per 100 cotton plants sampled.
When he came back to spray two days later, his research team could find no adult plant bugs.
“In this case, the test plots were surrounded by corn and the plant bugs moved that quickly out of cotton into corn,” Reisig said.
“It’s important for growers to remember, however, that plant bugs can move back into cotton from corn or other crops just as rapidly,” he added.
Herbert says some late planted crops may be attacked by three formidable pests simultaneously. “We had a situation in Virginia, and other parts of the Southeast I suspect, that we’ve never seen before because of the pushback on planting dates created by excessive rainfall,” Herbert said.
“For example, we had late-planted soybeans that had kudzu bugs, stink bugs and corn earworms in the same field. How infestations of these insects lines up should determine how they are managed.
“In some fields one well-timed insecticide may do the job, but in others a separate spray for each insect may be needed.
“If you spray kudzu bugs with a pyrethroid and corn earworms are building, the risk is high you will create a bigger corn earworm problem.
“We have decent triggers for when to spray each insect, but we’ve rarely had all three in fields at one time, so we don’t really know how taking out one insect might create problems for another,” Herbert said.
The products to manage each insect are available. The trick is to pick the right active ingredient and apply it at the right time. Otherwise, the result can be the same as Reisig’s analogy about trying to use the wrong size crescent wrench — it just won’t work.
In the Upper Southeast a lot more grain sorghum was planted this year and a good part of it was planted in a double-crop with wheat. Rain significantly slowed down wheat harvest and pushed back planting date for double-crop sorghum and soybeans.