I live on Solomons Island in southern Calvert County. There is a large tree (a juniper I think, about 8 m tall) on public property near the Solomons Island Riverwalk that is heavily infested with bagworms. I will try and find someone in Calvert County government who will accept responsibility to do something about it but that will take time and, I'm not optimistic. I'd even consider doing it myself. My question to you is, how to best do this? What kind of chemical, method of application, best time to apply, etc. Also - this tree is only thirty feet from the Patuxent River.
You are good to notice and care as overtime bagworms can multiply and eventual kill a tree.
There are a few ways to control them, and happily 2 of them are totally safe, which are hand removal of bags, and/or a carefully timed spray of a biological control (Bt).
Here is our page on Bagworms that explains in more detail: