They’re hungry and growers need to take action against them if they can. Fall armyworms are stripping pastures across south Georgia and moving north briskly.
“There are a lot of hay fields that haven’t even been cut the first time because of the rainy weather. By now, we would typically have made the second cutting or even third in far south Georgia,” says Dennis Hancock, University of Georgia Cooperative Extension forage specialist.
It’s tough to impossible to get insecticide deep enough into the thick biomass in most fields now, Hancock said. And any areas that have been taken over by tall-growing weeds like johnsongrass and vaseygrass, will pose major problems. Spray booms are unlikely to clear many of those patches.
“Some are reporting that complete fields have been stripped and that only the stems remain. This obviously poses a major economic loss, but if producers do not act, the effects could ruin the next cutting,” Hancock said.
Waiting for the stripped stems in the field to regrow is a bad idea, Hancock said. “First, even if the fields have been stripped of leaves, the stems remaining will still be too much biomass to leave in the field. This residue will severely reduce bermudagrass productivity,” Hancock says. “Bermudagrass does not tolerate shade and will not grow well through such residue.”
In most cases, the only real option is to cut and bale off or remove the stripped stems. The quality of it will be extremely poor, but it’s likely necessary to protect the next cutting, Hancock says.
“Fall armyworms are terrible right now. I just came from a bermudagrass hay field (week of July 24) that was infested and lots of the leaves were heavily eaten. Yesterday, we looked at some pearl millet for grazing that had lots of the caterpillars eating their fill. I had been in the field a week ago and didn’t notice them at that time,” says Rome Ethredge, University of Georgia Cooperative Extension agent in Seminole County, Ga., near the Florida and Alabama lines.
Ethredge said the problem with these caterpillars “is that they lay low when young and don’t eat that much. When they get close to an inch long, it’s incredible how much they can eat, especially if their populations are high.”
Check all pastures and hay fields for this pest, Ethredge said. White egrets and cow birds in fields feeding are a good indication of a fall armyworm problem. The birds provide some biological control but usually not enough.