Velvetbean caterpillars (VBC) have arrived in large numbers in some Georgia peanut fields over the past couple weeks. Peanuts that are 70 to 90 days after planting are likely to be at greatest risk for yield loss from defoliation; the risk is even greater in fields that are drought stressed. VBCs have voracious appetites and can completely defoliate peanuts if left unchecked.
This pest has been easy to kill in recent years. A pyrethroid would be my choice for VBC in irrigated fields. I recommend growers choose a caterpillar specific product in non-irrigated fields. The selective, caterpillar specific insecticides will be more expensive up front, but they generally provide better residual activity and result in a much lower risk of secondary pest infestation. This is important with the hot, dry weather we are seeing in many areas, and I expect spider mite infestations will become more plentiful in the coming weeks.
Drought stressed peanut fields need to be checked for lesser cornstalk borer (LCB) infestation. Allowing LCB populations to continue to grow will result in lost yield and significantly increase the risk of Aspergillus flavus.
We need to be checking every peanut field for foliage feeding caterpillars and focusing our LCB scouting in areas with moisture stress. If you were waiting for the opportune moment to scout your peanuts, this is it.
If you have questions about controlling caterpillars, mites, or other pests in peanut, contact your local UGA County Extension Agent.