August 2025 Peanut Insect Update: Where Are the Caterpillars?

 

Dr. Mark Abney, UGA Extension Crop Entomologist

At the risk of jinxing the whole dang thing, the question I have gotten most in recent days from peanut farmers, county agents, and consultants has been, “Where are the caterpillars?” The short answer is that I don’t know where the caterpillars are. Caterpillar pressure has been lighter than average across most of Georgia in 2025. The most common species I am seeing in fields is the rednecked peanut worm, and it is not considered a major pest.

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As always, the best thing a grower can do is scout, or pay someone to scout, fields every week and treat only when thresholds are reached. Three reports of fields with caterpillars above threshold came in today. Is this the beginning of a larger trend? No one knows yet. There is no reason to apply an insecticide to a peanut field because there are supposed to be caterpillars there in mid-August. There are plenty of reasons to scout and base management decisions on the real-time pest pressure in the field. Every dollar we don’t have to spend killing insects is a dollar we get to keep in our pocket.

Potato leafhopper (PLH) and hopper burn continue to be topics of concern. Georgia has seen above average PLH populations in 2025.

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The impact of hopper burn on peanut yield is not known, and treating this insect with insecticides comes with some risk. Nearly all the active ingredients that have efficacy against PLH can flare spider mites. In addition, PLH is highly mobile and can move in and out of fields. The presence of hopper burn alone is not justification for an insecticide application, because the injury will remain even after the insects are gone. There is no reason to apply an insecticide to a peanut field because PLH was there last week.

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I have very little data, but the data I have suggests that PLH feeding is not likely to cause significant yield loss. Still, if you have questions or concerns, do not hesitate to contact your local County Extension Agent.