Fall Armyworms Brandenburg Peanut Notes No. 204 2021

Comments from Rick are provided relative to armyworms.

Fall Armyworms Out in Record Numbers


Rick Brandenburg, Extension Entomologist

This year we are seeing more fall armyworms than I have seen in 40 years as an extension entomologist. They have the potential to damage peanuts, but they are not as aggressive of feeders as corn earworms or budworms. Currently, in early Sep, the threshold for worms in 8-10 per row foot and I believe that with fall armyworm it should be higher, at least 12 and perhaps 15 worms per row foot. They are more difficult to control and the cost is higher as pyrethroids will not provide good control. Products such as Orthene, Danitol, Steward, Intrepid Edge, Blackhawk, Besiege, Prevathon, and Exirel should all do a good job (at a cost).

In the past, there have been instances that when peanuts are dug, the fall armyworms move up and feed on pods. Some of you have seen them falling out of trailers. I really don’t know how much damage these do, but I know it can be a scary site. The challenge is what can be applied at 0 days preharvest. I am going to have to review our options before I put anything out, but we could see this problem occur this year. I will plan to talk about it at the Peanut Field Day in Lewiston this Thursday.

Armyworms