have you tried milky spore powder...that is safe for the birds and anything else that may eat the larva it is about 20 dollars per container but it is worth the price...
Of course, I can't figure out how to add pictures of the infestation. Hubby dumped about 100 lbs of some Ortho dust. I know, I know. The birds, other bugs and anything else that might make their way through the powder. My 13 chickens wouldn't have made a dent in the population. And we don;t let them out unless we are home. And I think the neighbor down the road (about a 1/4 mile)is having the same issue. His lawn is suddenly dead. I've sent an email to the DEC to see what they think.
I was just thinking about 10 guineas would rock those larvae out in a couple of days! I would let the chickens go out there for a day or 2, then put them up and dust after.
Armyworms. That is what those nasty buggers are. Western NY is having a major issue with them right now. Most likely eggs were laid in fields and once they march through fields, they move onto the next piece of property. Our property borders a large field of wheat. The pesticide we put down seems to have taken care of most of the critters. I would need a flock of 100's of chickens to take care of the worms. And there may be more 2 more emergence periods of this worm. YAY!
I remember years ago, cotton feilds were plague with black catapillars! When they crawl across the road, it looks like the road was in waves! it was eerie!! One time we were infected with white flies and grasshoppers.