I have been getting scattered reports of lesser cornstalk borer (LCB) in Georgia peanuts for several weeks now. The very dry conditions that we experienced to start the season were perfect for LCB survival, and they showed up early enough in the year to cause me no small amount of concern.
The recent rain that has fallen (at least in the Tifton area) will certainly help, and if rainy conditions continue LCB populations will probably fizzle. However, if hot dry weather returns, insect numbers could increase quickly.
Finding LCB larvae in a field immediately after a heavy rain can be difficult, but that does not necessarily mean they are gone. While LCB does not thrive in wet conditions, one or two rain events will not eliminate the pest once it is established.
Fields should be scouted carefully to determine if infestations are active. LCB moths are easy to detect as you walk through the field, and moths are a good indication that the caterpillars are or will soon be feeding on the plants.
If you have questions about lesser cornstalk borer scouting and management, please contact your local county Extension agent.