Home lawns, sports fields and golf courses across the southeast and mid-Atlantic had a quite surprising fall season on the turf pest front: a record invasion of fall armyworms (FAW) caused a tremendous amount of damage to turf. While the southeast is will acquainted with this troublesome pest, areas in Virginia, Pennsylvania, and Maryland don’t often see FAW, and especially not at the level observed in 2021.
These pests feed on turfgrass and can make quick work of large areas, so it is essential to recognize FAW and know what to do as soon as you spot them. There are preventative and curative options. Going into 2022, here are some tips for being prepared and recognizing these insects:
In the southeast, FAW typically emerge in summer. The further north locations require the moths to travel to lay their egg masses, so the worms may emerge in late summer/early fall. Spotting early arrivers can help you get ahead of the problem.
In some areas, chlorantraniliprole (Acelepryn) applied in spring for preventive white grub control provided exceptional control of white grubs and caterpillars. But for those who didn’t have this kind of pretreatment luck, some tips1 for treating FAW include:
1) treat early in their development
2) apply contact insecticides to the foliage
3) don’t water it in or mow it off
4) apply late in the day so the caterpillars acquire the residue while foraging.
5.) pyrethroids are probably the most efficacious contacts available, but spinosads and indoxacarb are “softer” chemistries.
1McGraw, Ben. “Looking Back at the Fall Armyworm Invasion of 2021.” Pennsylvania Turfgrass, Winter 2022. Vol. 11/No. 1. pp.16-17