Fall Armyworms (FAW) are moving their way up through South Carolina and will likely be in NC in the next few weeks. FAWs are 1-1/2 inch long caterpillars and come in a variety of colors including green, mottled brown and brown-black. They can often be distinguished by the light-colored, upside-down “Y” shape on their head capsule (pic).
Although these insects do not overwinter in NC, the adult moths are capable of traveling great distances in a short period of time and can fly north from overwintering areas in a few short weeks. Females will lay their eggs on flat surfaces near managed turfgrass, particularly structures like building walls and signs, although they can also take advantage of nearby ornamental plant surfaces. Unlike other caterpillar species, FAWs will feed during the day (or night) and can be seen “army crawling” across the turf surface (pic), especially early in the morning.
FAW damage can often be more easy to diagnose than that of other turf insect pests. While crawling across the turf surface, caterpillars will consume leaf tissue, leaving behind large, brown areas. FAWs travel in large groups and often the damage will create a distinct line between damaged and undamaged turfgrass. Although FAW are not restricted to a particular grass species, newly-installed sod seems to be the most attractive and susceptible to damage.
For more specific control recommendations, check out the FAW Turf Insect Info Sheet on Turffiles.