There has been no rain in Tift County this week, and as I walked my plots and a commercial field this morning I saw a few lesser cornstalk borer larvae in the sandy parts of non-irrigated fields. High temperatures combined with dry conditions favor three of the most troublesome arthropod pests of peanut: lesser cornstalk borer, two spotted spider mite, and peanut burrower bug. I have gotten a couple calls over the last few days about lessers, but I have not heard any reports of spider mites in peanut yet.
I urge growers to be diligent in scouting fields for mites. Should mite populations develop in a field we need to be sure to avoid using pyrethroid insecticides at that location. A lot of growers will make an “automatic application” of a pyrethroid in July for three cornered alfalfa hoppers. Pyrethroids will flare spider mite populations and make the situation worse. I would much rather let the threecornered alfalfa hoppers feed than risk creating an all out spider mite infestation. Bifenthrin is a pyrethroid that has been sold to growers in recent years specifically for spider mite control. Though mite populations can decline immediately following an application of bifenthrin, if environmental conditions remain favorable for mite growth, they almost always return to and surpass pre-treatment levels.
If you have any questions about these or other insect pests of peanut, please contact your local University of Georgia County Extension Agent.