Q.How to treat bag worms when it’s September
I had bag worms last fall and was told it couldn’t be treated that time of the year. I was hoping the winter freeze killed them, but they are showing up again as I noticed leaves missing from the trees. It is September. Is there anything I can do to treat?
This article has the answers you're looking for : https://www.gardeningknowhow.com/plant-problems/pests/insects/treatment-bagworms.htm