Fall Armyworm Alert


Sure, insects are difficult to predict.

But sometimes the signs are so clear that we can almost guarantee certain pests will show up in our lawns.

Enter the fall armyworm. Problems with this pest may be on the horizon again this year. A lot of armyworm egg masses have already been found, according to Peter Hertl and Rick Brandenburg with North Carolina State University in Raleigh, North Carolina, so egg-hatch and armyworm larvae entering the turf will not be far behind.

This potentially could lead to big problems in late summer. Therefore, turf managers should start conducting regular scouting for armyworms and be prepared to implement control if necessary, Hertl and Brandenburg advise.

Fall armyworms feed on a wide range of plants but prefer grasses. Damage to bermudagrass in the Southern U.S. is most common, but fall armyworm also munch on fescue, ryegrass, bentgrass and bluegrass. Lush, green turf is the pest’s most frequent target.

While bermudagrass usually can recover from this damage, Brandenburg says fall armyworm feeding in late fall may stress the turf going into the winter and result in some winterkill. Cool-season turf, on the other hand, can be permanently damaged if the growing tips are destroyed.

To control the fall armyworm, early detection is key. “Areas where flocks of birds are seen feeding in the turf should be checked immediately, as the birds may be feeding on armyworms,” Brandenburg says.

“Control of fall armyworms will be improved if you cut the turf prior to treating,” Brandenburg explains. “A light irrigation prior to treatment may also help, as will treating late in the day. If possible, do not mow turf and remove clippings for several days after treating.”

Timing is important and a repeat application may be necessary in some situations, Hertl and Brandenburg recommend.