Fall Armyworm

August 31, 2021

The past two months I have been watching various social media stories about how bad fall armyworm (Spodoptera frugiperda) pressure is in the states to the south of Iowa. There has been extensive damage in Alabama, Tennessee, Georgia, Kansas, and Missouri to name a few. As time has progressed the damage has moved north into Ohio, Indiana, and Maryland. The fall armyworm caterpillar will devour turfgrass by eating foliage down to the crown. The crown is then left exposed to desicate in warm temperatures. Golf course fairways, athletic fields and home lawns have all been damaged by fall armyworms in these states. On Monday I got the first picutres of egg masses of fall armyworms in Iowa.

We don't regularly see fall armyworms in Iowa, and they arrive with storms and winds from the southern U.S. The southeastern part of the U.S. has seen prolonged damage from multiple genrations of fall armyworms. Storms the past week or so have brought these pests to Iowa. The female moths have seemed to lay the eggs in places such as on the flag and flag stick of a golf course, trash cans, golf carts, and sides of houses. This is not normal. The eggs can hatch in a few days. Many of the young caterpilars will not make it to the turfgrass and will die. If you see the egg masses you can scrape them off with soapy water. Scout for damage and feeding once the eggs have hatched. Blanket applicaitons of insecticide are not recommended, and scouting for damage is best.  

As of writting this blog I have yet to see any of the adults, however there have been some reports of damage from other ISU Extension Specialist. For more information check out this article in Horticulture and Home Pest News.