What is in this article?:
- Mid-South insect infestations this spring have featured many of the usual suspects, thrips, bollworms, plant bugs and spider mites. But unexpected visitors are also crashing the party, including surprisingly high numbers of yellow-striped army worms.
- Spider mites and plant bugs have been heavy in Arkansas, Mississippi and Tennessee.
- Cotton bollworm trap counts in Arkansas are 20 percent to 30 percent higher than last year, which was a heavy bollworm year.
According to Angus Catchot, Mississippi State University associate Extension professor of entomology and plant pathology, spider mites and plant bugs have been primary pests in cotton. “Up until recently, we’ve under some serious drought stress, which has exacerbated the problems we’ve been having with spider mites. We’ve been treating a number of acres, particularly in the south Delta.”
Plant bug numbers “have been very high,” Catchot said. “We’ve been dealing with a lot of migration out of corn, Group 4 soybeans and other wild hosts. It’s required a number of treatments to keep them under control.”
Catchot is concerned that the lateness of the cotton crop — much of which had not reached the flowering stage by the end of June — could be problematic at the end of the season. “We have data that shows that early planting can reduce insecticide sprays on plant bugs by 50 percent to 60 percent.
“Well beyond 50 percent of the crop was planted past May 10 to May 15. We’re dealing with big migrations of adult plant bugs into the fields. Producers make an application, and when they check the field again, the numbers are the same or even higher. It’s not that they’re not getting control. The bugs are just moving in behind them. We’re hoping that this will start to slow down in the next 10 days to two weeks.”
In the north Delta, Palmer pigweed “is a tremendous host for tarnished plant bugs. That is going to be a constant source of plant bugs.”
Catchot says growers “have to stay on top of populations that are moving in. When square retention starts dropping, we’re going to have to tighten our intervals. We may not be able to get seven to 10 days out of the products available to us.”
Insects in soybeans as of the end of June “have been abnormally quiet to this point,” Catchot said.